Xbox-GDK-Samples/Kits/DirectXTex/BC6HBC7.cpp

3660 строки
147 KiB
C++

//-------------------------------------------------------------------------------------
// BC6HBC7.cpp
//
// Block-compression (BC) functionality for BC6H and BC7 (DirectX 11 texture compression)
//
// Copyright (c) Microsoft Corporation.
// Licensed under the MIT License.
//
// http://go.microsoft.com/fwlink/?LinkId=248926
//-------------------------------------------------------------------------------------
#include "DirectXTexP.h"
#include "BC.h"
using namespace DirectX;
using namespace DirectX::PackedVector;
//-------------------------------------------------------------------------------------
// Macros
//-------------------------------------------------------------------------------------
#define SIGN_EXTEND(x,nb) ((((x)&(1<<((nb)-1)))?((~0)^((1<<(nb))-1)):0)|(x))
// Because these are used in SAL annotations, they need to remain macros rather than const values
#define BC6H_MAX_REGIONS 2
#define BC6H_MAX_INDICES 16
#define BC7_MAX_REGIONS 3
#define BC7_MAX_INDICES 16
namespace
{
//-------------------------------------------------------------------------------------
// Constants
//-------------------------------------------------------------------------------------
constexpr uint16_t F16S_MASK = 0x8000; // f16 sign mask
constexpr uint16_t F16EM_MASK = 0x7fff; // f16 exp & mantissa mask
constexpr uint16_t F16MAX = 0x7bff; // MAXFLT bit pattern for XMHALF
constexpr size_t BC6H_NUM_CHANNELS = 3;
constexpr size_t BC6H_MAX_SHAPES = 32;
constexpr size_t BC7_NUM_CHANNELS = 4;
constexpr size_t BC7_MAX_SHAPES = 64;
constexpr int32_t BC67_WEIGHT_MAX = 64;
constexpr uint32_t BC67_WEIGHT_SHIFT = 6;
constexpr int32_t BC67_WEIGHT_ROUND = 32;
constexpr float fEpsilon = (0.25f / 64.0f) * (0.25f / 64.0f);
constexpr float pC3[] = { 2.0f / 2.0f, 1.0f / 2.0f, 0.0f / 2.0f };
constexpr float pD3[] = { 0.0f / 2.0f, 1.0f / 2.0f, 2.0f / 2.0f };
constexpr float pC4[] = { 3.0f / 3.0f, 2.0f / 3.0f, 1.0f / 3.0f, 0.0f / 3.0f };
constexpr float pD4[] = { 0.0f / 3.0f, 1.0f / 3.0f, 2.0f / 3.0f, 3.0f / 3.0f };
// Partition, Shape, Pixel (index into 4x4 block)
const uint8_t g_aPartitionTable[3][64][16] =
{
{ // 1 Region case has no subsets (all 0)
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
},
{ // BC6H/BC7 Partition Set for 2 Subsets
{ 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1 }, // Shape 0
{ 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1 }, // Shape 1
{ 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1 }, // Shape 2
{ 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1 }, // Shape 3
{ 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1 }, // Shape 4
{ 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1 }, // Shape 5
{ 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1 }, // Shape 6
{ 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 1, 1 }, // Shape 7
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1 }, // Shape 8
{ 0, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 }, // Shape 9
{ 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1 }, // Shape 10
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 1 }, // Shape 11
{ 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 }, // Shape 12
{ 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1 }, // Shape 13
{ 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 }, // Shape 14
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1 }, // Shape 15
{ 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1 }, // Shape 16
{ 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0 }, // Shape 17
{ 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0 }, // Shape 18
{ 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0 }, // Shape 19
{ 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0 }, // Shape 20
{ 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0 }, // Shape 21
{ 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0 }, // Shape 22
{ 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1 }, // Shape 23
{ 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0 }, // Shape 24
{ 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0 }, // Shape 25
{ 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0 }, // Shape 26
{ 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0 }, // Shape 27
{ 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0 }, // Shape 28
{ 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0 }, // Shape 29
{ 0, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0 }, // Shape 30
{ 0, 0, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0 }, // Shape 31
// BC7 Partition Set for 2 Subsets (second-half)
{ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1 }, // Shape 32
{ 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1 }, // Shape 33
{ 0, 1, 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0 }, // Shape 34
{ 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0 }, // Shape 35
{ 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0 }, // Shape 36
{ 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0 }, // Shape 37
{ 0, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 1 }, // Shape 38
{ 0, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1 }, // Shape 39
{ 0, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0 }, // Shape 40
{ 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 0 }, // Shape 41
{ 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0 }, // Shape 42
{ 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 0, 0 }, // Shape 43
{ 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0 }, // Shape 44
{ 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 1, 1 }, // Shape 45
{ 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1 }, // Shape 46
{ 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 0, 0 }, // Shape 47
{ 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0 }, // Shape 48
{ 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 0, 0 }, // Shape 49
{ 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0 }, // Shape 50
{ 0, 0, 0, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0 }, // Shape 51
{ 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1 }, // Shape 52
{ 0, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1 }, // Shape 53
{ 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 0 }, // Shape 54
{ 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 1, 0 }, // Shape 55
{ 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1 }, // Shape 56
{ 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1 }, // Shape 57
{ 0, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1 }, // Shape 58
{ 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1 }, // Shape 59
{ 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1 }, // Shape 60
{ 0, 0, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0 }, // Shape 61
{ 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0 }, // Shape 62
{ 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 1, 1 } // Shape 63
},
{ // BC7 Partition Set for 3 Subsets
{ 0, 0, 1, 1, 0, 0, 1, 1, 0, 2, 2, 1, 2, 2, 2, 2 }, // Shape 0
{ 0, 0, 0, 1, 0, 0, 1, 1, 2, 2, 1, 1, 2, 2, 2, 1 }, // Shape 1
{ 0, 0, 0, 0, 2, 0, 0, 1, 2, 2, 1, 1, 2, 2, 1, 1 }, // Shape 2
{ 0, 2, 2, 2, 0, 0, 2, 2, 0, 0, 1, 1, 0, 1, 1, 1 }, // Shape 3
{ 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 1, 1, 2, 2 }, // Shape 4
{ 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 2, 2, 0, 0, 2, 2 }, // Shape 5
{ 0, 0, 2, 2, 0, 0, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1 }, // Shape 6
{ 0, 0, 1, 1, 0, 0, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1 }, // Shape 7
{ 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2 }, // Shape 8
{ 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2 }, // Shape 9
{ 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2 }, // Shape 10
{ 0, 0, 1, 2, 0, 0, 1, 2, 0, 0, 1, 2, 0, 0, 1, 2 }, // Shape 11
{ 0, 1, 1, 2, 0, 1, 1, 2, 0, 1, 1, 2, 0, 1, 1, 2 }, // Shape 12
{ 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 2, 0, 1, 2, 2 }, // Shape 13
{ 0, 0, 1, 1, 0, 1, 1, 2, 1, 1, 2, 2, 1, 2, 2, 2 }, // Shape 14
{ 0, 0, 1, 1, 2, 0, 0, 1, 2, 2, 0, 0, 2, 2, 2, 0 }, // Shape 15
{ 0, 0, 0, 1, 0, 0, 1, 1, 0, 1, 1, 2, 1, 1, 2, 2 }, // Shape 16
{ 0, 1, 1, 1, 0, 0, 1, 1, 2, 0, 0, 1, 2, 2, 0, 0 }, // Shape 17
{ 0, 0, 0, 0, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 2, 2 }, // Shape 18
{ 0, 0, 2, 2, 0, 0, 2, 2, 0, 0, 2, 2, 1, 1, 1, 1 }, // Shape 19
{ 0, 1, 1, 1, 0, 1, 1, 1, 0, 2, 2, 2, 0, 2, 2, 2 }, // Shape 20
{ 0, 0, 0, 1, 0, 0, 0, 1, 2, 2, 2, 1, 2, 2, 2, 1 }, // Shape 21
{ 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 2, 2, 0, 1, 2, 2 }, // Shape 22
{ 0, 0, 0, 0, 1, 1, 0, 0, 2, 2, 1, 0, 2, 2, 1, 0 }, // Shape 23
{ 0, 1, 2, 2, 0, 1, 2, 2, 0, 0, 1, 1, 0, 0, 0, 0 }, // Shape 24
{ 0, 0, 1, 2, 0, 0, 1, 2, 1, 1, 2, 2, 2, 2, 2, 2 }, // Shape 25
{ 0, 1, 1, 0, 1, 2, 2, 1, 1, 2, 2, 1, 0, 1, 1, 0 }, // Shape 26
{ 0, 0, 0, 0, 0, 1, 1, 0, 1, 2, 2, 1, 1, 2, 2, 1 }, // Shape 27
{ 0, 0, 2, 2, 1, 1, 0, 2, 1, 1, 0, 2, 0, 0, 2, 2 }, // Shape 28
{ 0, 1, 1, 0, 0, 1, 1, 0, 2, 0, 0, 2, 2, 2, 2, 2 }, // Shape 29
{ 0, 0, 1, 1, 0, 1, 2, 2, 0, 1, 2, 2, 0, 0, 1, 1 }, // Shape 30
{ 0, 0, 0, 0, 2, 0, 0, 0, 2, 2, 1, 1, 2, 2, 2, 1 }, // Shape 31
{ 0, 0, 0, 0, 0, 0, 0, 2, 1, 1, 2, 2, 1, 2, 2, 2 }, // Shape 32
{ 0, 2, 2, 2, 0, 0, 2, 2, 0, 0, 1, 2, 0, 0, 1, 1 }, // Shape 33
{ 0, 0, 1, 1, 0, 0, 1, 2, 0, 0, 2, 2, 0, 2, 2, 2 }, // Shape 34
{ 0, 1, 2, 0, 0, 1, 2, 0, 0, 1, 2, 0, 0, 1, 2, 0 }, // Shape 35
{ 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 0, 0, 0, 0 }, // Shape 36
{ 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0, 1, 2, 0 }, // Shape 37
{ 0, 1, 2, 0, 2, 0, 1, 2, 1, 2, 0, 1, 0, 1, 2, 0 }, // Shape 38
{ 0, 0, 1, 1, 2, 2, 0, 0, 1, 1, 2, 2, 0, 0, 1, 1 }, // Shape 39
{ 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 0, 0, 0, 0, 1, 1 }, // Shape 40
{ 0, 1, 0, 1, 0, 1, 0, 1, 2, 2, 2, 2, 2, 2, 2, 2 }, // Shape 41
{ 0, 0, 0, 0, 0, 0, 0, 0, 2, 1, 2, 1, 2, 1, 2, 1 }, // Shape 42
{ 0, 0, 2, 2, 1, 1, 2, 2, 0, 0, 2, 2, 1, 1, 2, 2 }, // Shape 43
{ 0, 0, 2, 2, 0, 0, 1, 1, 0, 0, 2, 2, 0, 0, 1, 1 }, // Shape 44
{ 0, 2, 2, 0, 1, 2, 2, 1, 0, 2, 2, 0, 1, 2, 2, 1 }, // Shape 45
{ 0, 1, 0, 1, 2, 2, 2, 2, 2, 2, 2, 2, 0, 1, 0, 1 }, // Shape 46
{ 0, 0, 0, 0, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1 }, // Shape 47
{ 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 2, 2, 2, 2 }, // Shape 48
{ 0, 2, 2, 2, 0, 1, 1, 1, 0, 2, 2, 2, 0, 1, 1, 1 }, // Shape 49
{ 0, 0, 0, 2, 1, 1, 1, 2, 0, 0, 0, 2, 1, 1, 1, 2 }, // Shape 50
{ 0, 0, 0, 0, 2, 1, 1, 2, 2, 1, 1, 2, 2, 1, 1, 2 }, // Shape 51
{ 0, 2, 2, 2, 0, 1, 1, 1, 0, 1, 1, 1, 0, 2, 2, 2 }, // Shape 52
{ 0, 0, 0, 2, 1, 1, 1, 2, 1, 1, 1, 2, 0, 0, 0, 2 }, // Shape 53
{ 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 2, 2, 2, 2 }, // Shape 54
{ 0, 0, 0, 0, 0, 0, 0, 0, 2, 1, 1, 2, 2, 1, 1, 2 }, // Shape 55
{ 0, 1, 1, 0, 0, 1, 1, 0, 2, 2, 2, 2, 2, 2, 2, 2 }, // Shape 56
{ 0, 0, 2, 2, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 2, 2 }, // Shape 57
{ 0, 0, 2, 2, 1, 1, 2, 2, 1, 1, 2, 2, 0, 0, 2, 2 }, // Shape 58
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 1, 1, 2 }, // Shape 59
{ 0, 0, 0, 2, 0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 1 }, // Shape 60
{ 0, 2, 2, 2, 1, 2, 2, 2, 0, 2, 2, 2, 1, 2, 2, 2 }, // Shape 61
{ 0, 1, 0, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 }, // Shape 62
{ 0, 1, 1, 1, 2, 0, 1, 1, 2, 2, 0, 1, 2, 2, 2, 0 } // Shape 63
}
};
// Partition, Shape, Fixup
const uint8_t g_aFixUp[3][64][3] =
{
{ // No fix-ups for 1st subset for BC6H or BC7
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },
{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 },{ 0, 0, 0 }
},
{ // BC6H/BC7 Partition Set Fixups for 2 Subsets
{ 0,15, 0 },{ 0,15, 0 },{ 0,15, 0 },{ 0,15, 0 },
{ 0,15, 0 },{ 0,15, 0 },{ 0,15, 0 },{ 0,15, 0 },
{ 0,15, 0 },{ 0,15, 0 },{ 0,15, 0 },{ 0,15, 0 },
{ 0,15, 0 },{ 0,15, 0 },{ 0,15, 0 },{ 0,15, 0 },
{ 0,15, 0 },{ 0, 2, 0 },{ 0, 8, 0 },{ 0, 2, 0 },
{ 0, 2, 0 },{ 0, 8, 0 },{ 0, 8, 0 },{ 0,15, 0 },
{ 0, 2, 0 },{ 0, 8, 0 },{ 0, 2, 0 },{ 0, 2, 0 },
{ 0, 8, 0 },{ 0, 8, 0 },{ 0, 2, 0 },{ 0, 2, 0 },
// BC7 Partition Set Fixups for 2 Subsets (second-half)
{ 0,15, 0 },{ 0,15, 0 },{ 0, 6, 0 },{ 0, 8, 0 },
{ 0, 2, 0 },{ 0, 8, 0 },{ 0,15, 0 },{ 0,15, 0 },
{ 0, 2, 0 },{ 0, 8, 0 },{ 0, 2, 0 },{ 0, 2, 0 },
{ 0, 2, 0 },{ 0,15, 0 },{ 0,15, 0 },{ 0, 6, 0 },
{ 0, 6, 0 },{ 0, 2, 0 },{ 0, 6, 0 },{ 0, 8, 0 },
{ 0,15, 0 },{ 0,15, 0 },{ 0, 2, 0 },{ 0, 2, 0 },
{ 0,15, 0 },{ 0,15, 0 },{ 0,15, 0 },{ 0,15, 0 },
{ 0,15, 0 },{ 0, 2, 0 },{ 0, 2, 0 },{ 0,15, 0 }
},
{ // BC7 Partition Set Fixups for 3 Subsets
{ 0, 3,15 },{ 0, 3, 8 },{ 0,15, 8 },{ 0,15, 3 },
{ 0, 8,15 },{ 0, 3,15 },{ 0,15, 3 },{ 0,15, 8 },
{ 0, 8,15 },{ 0, 8,15 },{ 0, 6,15 },{ 0, 6,15 },
{ 0, 6,15 },{ 0, 5,15 },{ 0, 3,15 },{ 0, 3, 8 },
{ 0, 3,15 },{ 0, 3, 8 },{ 0, 8,15 },{ 0,15, 3 },
{ 0, 3,15 },{ 0, 3, 8 },{ 0, 6,15 },{ 0,10, 8 },
{ 0, 5, 3 },{ 0, 8,15 },{ 0, 8, 6 },{ 0, 6,10 },
{ 0, 8,15 },{ 0, 5,15 },{ 0,15,10 },{ 0,15, 8 },
{ 0, 8,15 },{ 0,15, 3 },{ 0, 3,15 },{ 0, 5,10 },
{ 0, 6,10 },{ 0,10, 8 },{ 0, 8, 9 },{ 0,15,10 },
{ 0,15, 6 },{ 0, 3,15 },{ 0,15, 8 },{ 0, 5,15 },
{ 0,15, 3 },{ 0,15, 6 },{ 0,15, 6 },{ 0,15, 8 },
{ 0, 3,15 },{ 0,15, 3 },{ 0, 5,15 },{ 0, 5,15 },
{ 0, 5,15 },{ 0, 8,15 },{ 0, 5,15 },{ 0,10,15 },
{ 0, 5,15 },{ 0,10,15 },{ 0, 8,15 },{ 0,13,15 },
{ 0,15, 3 },{ 0,12,15 },{ 0, 3,15 },{ 0, 3, 8 }
}
};
const int g_aWeights2[] = { 0, 21, 43, 64 };
const int g_aWeights3[] = { 0, 9, 18, 27, 37, 46, 55, 64 };
const int g_aWeights4[] = { 0, 4, 9, 13, 17, 21, 26, 30, 34, 38, 43, 47, 51, 55, 60, 64 };
}
namespace DirectX
{
class LDRColorA
{
public:
uint8_t r, g, b, a;
LDRColorA() = default;
LDRColorA(uint8_t _r, uint8_t _g, uint8_t _b, uint8_t _a) noexcept : r(_r), g(_g), b(_b), a(_a) {}
LDRColorA(LDRColorA const&) = default;
LDRColorA& operator= (const LDRColorA&) = default;
LDRColorA(LDRColorA&&) = default;
LDRColorA& operator= (LDRColorA&&) = default;
const uint8_t& operator [] (_In_range_(0, 3) size_t uElement) const noexcept
{
switch (uElement)
{
case 0: return r;
case 1: return g;
case 2: return b;
case 3: return a;
default: assert(false); return r;
}
}
uint8_t& operator [] (_In_range_(0, 3) size_t uElement) noexcept
{
switch (uElement)
{
case 0: return r;
case 1: return g;
case 2: return b;
case 3: return a;
default: assert(false); return r;
}
}
LDRColorA operator = (_In_ const HDRColorA& c) noexcept
{
LDRColorA ret;
HDRColorA tmp(c);
tmp = tmp.Clamp(0.0f, 1.0f) * 255.0f;
ret.r = uint8_t(tmp.r + 0.001f);
ret.g = uint8_t(tmp.g + 0.001f);
ret.b = uint8_t(tmp.b + 0.001f);
ret.a = uint8_t(tmp.a + 0.001f);
return ret;
}
static void InterpolateRGB(_In_ const LDRColorA& c0, _In_ const LDRColorA& c1, _In_ size_t wc, _In_ _In_range_(2, 4) size_t wcprec, _Out_ LDRColorA& out) noexcept
{
const int* aWeights = nullptr;
switch (wcprec)
{
case 2: aWeights = g_aWeights2; assert(wc < 4); _Analysis_assume_(wc < 4); break;
case 3: aWeights = g_aWeights3; assert(wc < 8); _Analysis_assume_(wc < 8); break;
case 4: aWeights = g_aWeights4; assert(wc < 16); _Analysis_assume_(wc < 16); break;
default: assert(false); out.r = out.g = out.b = 0; return;
}
out.r = uint8_t((uint32_t(c0.r) * uint32_t(BC67_WEIGHT_MAX - aWeights[wc]) + uint32_t(c1.r) * uint32_t(aWeights[wc]) + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT);
out.g = uint8_t((uint32_t(c0.g) * uint32_t(BC67_WEIGHT_MAX - aWeights[wc]) + uint32_t(c1.g) * uint32_t(aWeights[wc]) + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT);
out.b = uint8_t((uint32_t(c0.b) * uint32_t(BC67_WEIGHT_MAX - aWeights[wc]) + uint32_t(c1.b) * uint32_t(aWeights[wc]) + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT);
}
static void InterpolateA(_In_ const LDRColorA& c0, _In_ const LDRColorA& c1, _In_ size_t wa, _In_range_(2, 4) _In_ size_t waprec, _Out_ LDRColorA& out) noexcept
{
const int* aWeights = nullptr;
switch (waprec)
{
case 2: aWeights = g_aWeights2; assert(wa < 4); _Analysis_assume_(wa < 4); break;
case 3: aWeights = g_aWeights3; assert(wa < 8); _Analysis_assume_(wa < 8); break;
case 4: aWeights = g_aWeights4; assert(wa < 16); _Analysis_assume_(wa < 16); break;
default: assert(false); out.a = 0; return;
}
out.a = uint8_t((uint32_t(c0.a) * uint32_t(BC67_WEIGHT_MAX - aWeights[wa]) + uint32_t(c1.a) * uint32_t(aWeights[wa]) + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT);
}
static void Interpolate(_In_ const LDRColorA& c0, _In_ const LDRColorA& c1, _In_ size_t wc, _In_ size_t wa, _In_ _In_range_(2, 4) size_t wcprec, _In_ _In_range_(2, 4) size_t waprec, _Out_ LDRColorA& out) noexcept
{
InterpolateRGB(c0, c1, wc, wcprec, out);
InterpolateA(c0, c1, wa, waprec, out);
}
};
static_assert(sizeof(LDRColorA) == 4, "Unexpected packing");
struct LDREndPntPair
{
LDRColorA A;
LDRColorA B;
};
inline HDRColorA::HDRColorA(const LDRColorA& c) noexcept
{
r = float(c.r) * (1.0f / 255.0f);
g = float(c.g) * (1.0f / 255.0f);
b = float(c.b) * (1.0f / 255.0f);
a = float(c.a) * (1.0f / 255.0f);
}
inline HDRColorA& HDRColorA::operator = (const LDRColorA& c) noexcept
{
r = static_cast<float>(c.r);
g = static_cast<float>(c.g);
b = static_cast<float>(c.b);
a = static_cast<float>(c.a);
return *this;
}
inline LDRColorA HDRColorA::ToLDRColorA() const noexcept
{
return LDRColorA(static_cast<uint8_t>(r + 0.01f), static_cast<uint8_t>(g + 0.01f), static_cast<uint8_t>(b + 0.01f), static_cast<uint8_t>(a + 0.01f));
}
}
namespace
{
class INTColor
{
public:
int r, g, b;
int pad;
INTColor() = default;
INTColor(int nr, int ng, int nb) noexcept : r(nr), g(ng), b(nb), pad(0) {}
INTColor(INTColor const&) = default;
INTColor& operator= (const INTColor&) = default;
INTColor(INTColor&&) = default;
INTColor& operator= (INTColor&&) = default;
INTColor& operator += (_In_ const INTColor& c) noexcept
{
r += c.r;
g += c.g;
b += c.b;
return *this;
}
INTColor& operator -= (_In_ const INTColor& c) noexcept
{
r -= c.r;
g -= c.g;
b -= c.b;
return *this;
}
INTColor& operator &= (_In_ const INTColor& c) noexcept
{
r &= c.r;
g &= c.g;
b &= c.b;
return *this;
}
int& operator [] (_In_ uint8_t i) noexcept
{
assert(i < sizeof(INTColor) / sizeof(int));
_Analysis_assume_(i < sizeof(INTColor) / sizeof(int));
return reinterpret_cast<int*>(this)[i];
}
void Set(_In_ const HDRColorA& c, _In_ bool bSigned) noexcept
{
PackedVector::XMHALF4 aF16;
const XMVECTOR v = XMLoadFloat4(reinterpret_cast<const XMFLOAT4*>(&c));
XMStoreHalf4(&aF16, v);
r = F16ToINT(aF16.x, bSigned);
g = F16ToINT(aF16.y, bSigned);
b = F16ToINT(aF16.z, bSigned);
}
INTColor& Clamp(_In_ int iMin, _In_ int iMax) noexcept
{
r = std::min<int>(iMax, std::max<int>(iMin, r));
g = std::min<int>(iMax, std::max<int>(iMin, g));
b = std::min<int>(iMax, std::max<int>(iMin, b));
return *this;
}
INTColor& SignExtend(_In_ const LDRColorA& Prec) noexcept
{
r = SIGN_EXTEND(r, int(Prec.r));
g = SIGN_EXTEND(g, int(Prec.g));
b = SIGN_EXTEND(b, int(Prec.b));
return *this;
}
void ToF16(_Out_writes_(3) PackedVector::HALF aF16[3], _In_ bool bSigned) const noexcept
{
aF16[0] = INT2F16(r, bSigned);
aF16[1] = INT2F16(g, bSigned);
aF16[2] = INT2F16(b, bSigned);
}
private:
static int F16ToINT(_In_ const PackedVector::HALF& f, _In_ bool bSigned) noexcept
{
uint16_t input = *reinterpret_cast<const uint16_t*>(&f);
int out, s;
if (bSigned)
{
s = input & F16S_MASK;
input &= F16EM_MASK;
if (input > F16MAX) out = F16MAX;
else out = input;
out = s ? -out : out;
}
else
{
if (input & F16S_MASK) out = 0;
else out = input;
}
return out;
}
static PackedVector::HALF INT2F16(_In_ int input, _In_ bool bSigned) noexcept
{
PackedVector::HALF h;
uint16_t out;
if (bSigned)
{
int s = 0;
if (input < 0)
{
s = F16S_MASK;
input = -input;
}
out = uint16_t(s | input);
}
else
{
assert(input >= 0 && input <= F16MAX);
out = static_cast<uint16_t>(input);
}
*reinterpret_cast<uint16_t*>(&h) = out;
return h;
}
};
static_assert(sizeof(INTColor) == 16, "Unexpected packing");
struct INTEndPntPair
{
INTColor A;
INTColor B;
};
template< size_t SizeInBytes >
class CBits
{
public:
uint8_t GetBit(_Inout_ size_t& uStartBit) const noexcept
{
assert(uStartBit < 128);
_Analysis_assume_(uStartBit < 128);
const size_t uIndex = uStartBit >> 3;
auto const ret = static_cast<uint8_t>((m_uBits[uIndex] >> (uStartBit - (uIndex << 3))) & 0x01);
uStartBit++;
return ret;
}
uint8_t GetBits(_Inout_ size_t& uStartBit, _In_ size_t uNumBits) const noexcept
{
if (uNumBits == 0) return 0;
assert(uStartBit + uNumBits <= 128 && uNumBits <= 8);
_Analysis_assume_(uStartBit + uNumBits <= 128 && uNumBits <= 8);
uint8_t ret;
const size_t uIndex = uStartBit >> 3;
const size_t uBase = uStartBit - (uIndex << 3);
if (uBase + uNumBits > 8)
{
const size_t uFirstIndexBits = 8 - uBase;
const size_t uNextIndexBits = uNumBits - uFirstIndexBits;
ret = static_cast<uint8_t>((unsigned(m_uBits[uIndex]) >> uBase) | ((unsigned(m_uBits[uIndex + 1]) & ((1u << uNextIndexBits) - 1)) << uFirstIndexBits));
}
else
{
ret = static_cast<uint8_t>((m_uBits[uIndex] >> uBase) & ((1 << uNumBits) - 1));
}
assert(ret < (1 << uNumBits));
uStartBit += uNumBits;
return ret;
}
void SetBit(_Inout_ size_t& uStartBit, _In_ uint8_t uValue) noexcept
{
assert(uStartBit < 128 && uValue < 2);
_Analysis_assume_(uStartBit < 128 && uValue < 2);
size_t uIndex = uStartBit >> 3;
const size_t uBase = uStartBit - (uIndex << 3);
m_uBits[uIndex] &= ~(1 << uBase);
m_uBits[uIndex] |= uValue << uBase;
uStartBit++;
}
void SetBits(_Inout_ size_t& uStartBit, _In_ size_t uNumBits, _In_ uint8_t uValue) noexcept
{
if (uNumBits == 0)
return;
assert(uStartBit + uNumBits <= 128 && uNumBits <= 8);
_Analysis_assume_(uStartBit + uNumBits <= 128 && uNumBits <= 8);
assert(uValue < (1 << uNumBits));
size_t uIndex = uStartBit >> 3;
const size_t uBase = uStartBit - (uIndex << 3);
if (uBase + uNumBits > 8)
{
const size_t uFirstIndexBits = 8 - uBase;
const size_t uNextIndexBits = uNumBits - uFirstIndexBits;
m_uBits[uIndex] &= ~(((1 << uFirstIndexBits) - 1) << uBase);
m_uBits[uIndex] |= uValue << uBase;
m_uBits[uIndex + 1] &= ~((1 << uNextIndexBits) - 1);
m_uBits[uIndex + 1] |= uValue >> uFirstIndexBits;
}
else
{
m_uBits[uIndex] &= ~(((1 << uNumBits) - 1) << uBase);
m_uBits[uIndex] |= uValue << uBase;
}
uStartBit += uNumBits;
}
private:
uint8_t m_uBits[SizeInBytes];
};
// BC6H compression (16 bits per texel)
class D3DX_BC6H : private CBits< 16 >
{
public:
void Decode(_In_ bool bSigned, _Out_writes_(NUM_PIXELS_PER_BLOCK) HDRColorA* pOut) const noexcept;
void Encode(_In_ bool bSigned, _In_reads_(NUM_PIXELS_PER_BLOCK) const HDRColorA* const pIn) noexcept;
private:
#pragma warning(push)
#pragma warning(disable : 4480)
enum EField : uint8_t
{
NA, // N/A
M, // Mode
D, // Shape
RW,
RX,
RY,
RZ,
GW,
GX,
GY,
GZ,
BW,
BX,
BY,
BZ,
};
#pragma warning(pop)
struct ModeDescriptor
{
EField m_eField;
uint8_t m_uBit;
};
struct ModeInfo
{
uint8_t uMode;
uint8_t uPartitions;
bool bTransformed;
uint8_t uIndexPrec;
LDRColorA RGBAPrec[BC6H_MAX_REGIONS][2];
};
#pragma warning(push)
#pragma warning(disable : 4512)
struct EncodeParams
{
float fBestErr;
const bool bSigned;
uint8_t uMode;
uint8_t uShape;
const HDRColorA* const aHDRPixels;
INTEndPntPair aUnqEndPts[BC6H_MAX_SHAPES][BC6H_MAX_REGIONS];
INTColor aIPixels[NUM_PIXELS_PER_BLOCK];
EncodeParams(const HDRColorA* const aOriginal, bool bSignedFormat) noexcept :
fBestErr(FLT_MAX), bSigned(bSignedFormat), uMode(0), uShape(0), aHDRPixels(aOriginal), aUnqEndPts{}, aIPixels{}
{
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
{
aIPixels[i].Set(aOriginal[i], bSigned);
}
}
};
#pragma warning(pop)
static int Quantize(_In_ int iValue, _In_ int prec, _In_ bool bSigned) noexcept;
static int Unquantize(_In_ int comp, _In_ uint8_t uBitsPerComp, _In_ bool bSigned) noexcept;
static int FinishUnquantize(_In_ int comp, _In_ bool bSigned) noexcept;
static bool EndPointsFit(_In_ const EncodeParams* pEP, _In_reads_(BC6H_MAX_REGIONS) const INTEndPntPair aEndPts[]) noexcept;
void GeneratePaletteQuantized(_In_ const EncodeParams* pEP, _In_ const INTEndPntPair& endPts,
_Out_writes_(BC6H_MAX_INDICES) INTColor aPalette[]) const noexcept;
float MapColorsQuantized(_In_ const EncodeParams* pEP, _In_reads_(np) const INTColor aColors[], _In_ size_t np, _In_ const INTEndPntPair &endPts) const noexcept;
float PerturbOne(_In_ const EncodeParams* pEP, _In_reads_(np) const INTColor aColors[], _In_ size_t np, _In_ uint8_t ch,
_In_ const INTEndPntPair& oldEndPts, _Out_ INTEndPntPair& newEndPts, _In_ float fOldErr, _In_ int do_b) const noexcept;
void OptimizeOne(_In_ const EncodeParams* pEP, _In_reads_(np) const INTColor aColors[], _In_ size_t np, _In_ float aOrgErr,
_In_ const INTEndPntPair &aOrgEndPts, _Out_ INTEndPntPair &aOptEndPts) const noexcept;
void OptimizeEndPoints(_In_ const EncodeParams* pEP, _In_reads_(BC6H_MAX_REGIONS) const float aOrgErr[],
_In_reads_(BC6H_MAX_REGIONS) const INTEndPntPair aOrgEndPts[],
_Out_writes_all_(BC6H_MAX_REGIONS) INTEndPntPair aOptEndPts[]) const noexcept;
static void SwapIndices(_In_ const EncodeParams* pEP, _Inout_updates_all_(BC6H_MAX_REGIONS) INTEndPntPair aEndPts[],
_In_reads_(NUM_PIXELS_PER_BLOCK) size_t aIndices[]) noexcept;
void AssignIndices(_In_ const EncodeParams* pEP, _In_reads_(BC6H_MAX_REGIONS) const INTEndPntPair aEndPts[],
_Out_writes_(NUM_PIXELS_PER_BLOCK) size_t aIndices[],
_Out_writes_(BC6H_MAX_REGIONS) float aTotErr[]) const noexcept;
void QuantizeEndPts(_In_ const EncodeParams* pEP, _Out_writes_(BC6H_MAX_REGIONS) INTEndPntPair* qQntEndPts) const noexcept;
void EmitBlock(_In_ const EncodeParams* pEP, _In_reads_(BC6H_MAX_REGIONS) const INTEndPntPair aEndPts[],
_In_reads_(NUM_PIXELS_PER_BLOCK) const size_t aIndices[]) noexcept;
void Refine(_Inout_ EncodeParams* pEP) noexcept;
static void GeneratePaletteUnquantized(_In_ const EncodeParams* pEP, _In_ size_t uRegion, _Out_writes_(BC6H_MAX_INDICES) INTColor aPalette[]) noexcept;
float MapColors(_In_ const EncodeParams* pEP, _In_ size_t uRegion, _In_ size_t np, _In_reads_(np) const size_t* auIndex) const noexcept;
float RoughMSE(_Inout_ EncodeParams* pEP) const noexcept;
private:
static constexpr uint8_t c_NumModes = 14;
static constexpr uint8_t c_NumModeInfo = 32;
static const ModeDescriptor ms_aDesc[c_NumModes][82];
static const ModeInfo ms_aInfo[c_NumModes];
static const int ms_aModeToInfo[c_NumModeInfo];
};
// BC67 compression (16b bits per texel)
class D3DX_BC7 : private CBits< 16 >
{
public:
void Decode(_Out_writes_(NUM_PIXELS_PER_BLOCK) HDRColorA* pOut) const noexcept;
void Encode(uint32_t flags, _In_reads_(NUM_PIXELS_PER_BLOCK) const HDRColorA* const pIn) noexcept;
private:
struct ModeInfo
{
uint8_t uPartitions;
uint8_t uPartitionBits;
uint8_t uPBits;
uint8_t uRotationBits;
uint8_t uIndexModeBits;
uint8_t uIndexPrec;
uint8_t uIndexPrec2;
LDRColorA RGBAPrec;
LDRColorA RGBAPrecWithP;
};
#pragma warning(push)
#pragma warning(disable : 4512)
struct EncodeParams
{
uint8_t uMode;
LDREndPntPair aEndPts[BC7_MAX_SHAPES][BC7_MAX_REGIONS];
LDRColorA aLDRPixels[NUM_PIXELS_PER_BLOCK];
const HDRColorA* const aHDRPixels;
EncodeParams(const HDRColorA* const aOriginal) noexcept : uMode(0), aEndPts{}, aLDRPixels{}, aHDRPixels(aOriginal) {}
};
#pragma warning(pop)
static uint8_t Quantize(_In_ uint8_t comp, _In_ uint8_t uPrec) noexcept
{
assert(0 < uPrec && uPrec <= 8);
const uint8_t rnd = std::min<uint8_t>(255u, static_cast<uint8_t>(unsigned(comp) + (1u << (7 - uPrec))));
return uint8_t(rnd >> (8u - uPrec));
}
static LDRColorA Quantize(_In_ const LDRColorA& c, _In_ const LDRColorA& RGBAPrec) noexcept
{
LDRColorA q;
q.r = Quantize(c.r, RGBAPrec.r);
q.g = Quantize(c.g, RGBAPrec.g);
q.b = Quantize(c.b, RGBAPrec.b);
if (RGBAPrec.a)
q.a = Quantize(c.a, RGBAPrec.a);
else
q.a = 255;
return q;
}
static uint8_t Unquantize(_In_ uint8_t comp, _In_ size_t uPrec) noexcept
{
assert(0 < uPrec && uPrec <= 8);
comp = static_cast<uint8_t>(unsigned(comp) << (8 - uPrec));
return uint8_t(comp | (comp >> uPrec));
}
static LDRColorA Unquantize(_In_ const LDRColorA& c, _In_ const LDRColorA& RGBAPrec) noexcept
{
LDRColorA q;
q.r = Unquantize(c.r, RGBAPrec.r);
q.g = Unquantize(c.g, RGBAPrec.g);
q.b = Unquantize(c.b, RGBAPrec.b);
q.a = RGBAPrec.a > 0 ? Unquantize(c.a, RGBAPrec.a) : 255u;
return q;
}
void GeneratePaletteQuantized(_In_ const EncodeParams* pEP, _In_ size_t uIndexMode, _In_ const LDREndPntPair& endpts,
_Out_writes_(BC7_MAX_INDICES) LDRColorA aPalette[]) const noexcept;
float PerturbOne(_In_ const EncodeParams* pEP, _In_reads_(np) const LDRColorA colors[], _In_ size_t np, _In_ size_t uIndexMode,
_In_ size_t ch, _In_ const LDREndPntPair &old_endpts,
_Out_ LDREndPntPair &new_endpts, _In_ float old_err, _In_ uint8_t do_b) const noexcept;
void Exhaustive(_In_ const EncodeParams* pEP, _In_reads_(np) const LDRColorA aColors[], _In_ size_t np, _In_ size_t uIndexMode,
_In_ size_t ch, _Inout_ float& fOrgErr, _Inout_ LDREndPntPair& optEndPt) const noexcept;
void OptimizeOne(_In_ const EncodeParams* pEP, _In_reads_(np) const LDRColorA colors[], _In_ size_t np, _In_ size_t uIndexMode,
_In_ float orig_err, _In_ const LDREndPntPair &orig_endpts, _Out_ LDREndPntPair &opt_endpts) const noexcept;
void OptimizeEndPoints(_In_ const EncodeParams* pEP, _In_ size_t uShape, _In_ size_t uIndexMode,
_In_reads_(BC7_MAX_REGIONS) const float orig_err[],
_In_reads_(BC7_MAX_REGIONS) const LDREndPntPair orig_endpts[],
_Out_writes_(BC7_MAX_REGIONS) LDREndPntPair opt_endpts[]) const noexcept;
void AssignIndices(_In_ const EncodeParams* pEP, _In_ size_t uShape, _In_ size_t uIndexMode,
_In_reads_(BC7_MAX_REGIONS) LDREndPntPair endpts[],
_Out_writes_(NUM_PIXELS_PER_BLOCK) size_t aIndices[], _Out_writes_(NUM_PIXELS_PER_BLOCK) size_t aIndices2[],
_Out_writes_(BC7_MAX_REGIONS) float afTotErr[]) const noexcept;
void EmitBlock(_In_ const EncodeParams* pEP, _In_ size_t uShape, _In_ size_t uRotation, _In_ size_t uIndexMode,
_In_reads_(BC7_MAX_REGIONS) const LDREndPntPair aEndPts[],
_In_reads_(NUM_PIXELS_PER_BLOCK) const size_t aIndex[],
_In_reads_(NUM_PIXELS_PER_BLOCK) const size_t aIndex2[]) noexcept;
void FixEndpointPBits(_In_ const EncodeParams* pEP, _In_reads_(BC7_MAX_REGIONS) const LDREndPntPair *pOrigEndpoints, _Out_writes_(BC7_MAX_REGIONS) LDREndPntPair *pFixedEndpoints) noexcept;
float Refine(_In_ const EncodeParams* pEP, _In_ size_t uShape, _In_ size_t uRotation, _In_ size_t uIndexMode) noexcept;
float MapColors(_In_ const EncodeParams* pEP, _In_reads_(np) const LDRColorA aColors[], _In_ size_t np, _In_ size_t uIndexMode,
_In_ const LDREndPntPair& endPts, _In_ float fMinErr) const noexcept;
static float RoughMSE(_Inout_ EncodeParams* pEP, _In_ size_t uShape, _In_ size_t uIndexMode) noexcept;
private:
static constexpr uint8_t c_NumModes = 8;
static const ModeInfo ms_aInfo[c_NumModes];
};
}
// BC6H Compression
const D3DX_BC6H::ModeDescriptor D3DX_BC6H::ms_aDesc[D3DX_BC6H::c_NumModes][82] =
{
{ // Mode 1 (0x00) - 10 5 5 5
{ M, 0}, { M, 1}, {GY, 4}, {BY, 4}, {BZ, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {RW, 8}, {RW, 9}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {GW, 8}, {GW, 9}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {BW, 8}, {BW, 9}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RX, 4},
{GZ, 4}, {GY, 0}, {GY, 1}, {GY, 2}, {GY, 3}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GX, 4},
{BZ, 0}, {GZ, 0}, {GZ, 1}, {GZ, 2}, {GZ, 3}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BX, 4},
{BZ, 1}, {BY, 0}, {BY, 1}, {BY, 2}, {BY, 3}, {RY, 0}, {RY, 1}, {RY, 2}, {RY, 3}, {RY, 4},
{BZ, 2}, {RZ, 0}, {RZ, 1}, {RZ, 2}, {RZ, 3}, {RZ, 4}, {BZ, 3}, { D, 0}, { D, 1}, { D, 2},
{ D, 3}, { D, 4},
},
{ // Mode 2 (0x01) - 7 6 6 6
{ M, 0}, { M, 1}, {GY, 5}, {GZ, 4}, {GZ, 5}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {BZ, 0}, {BZ, 1}, {BY, 4}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {BY, 5}, {BZ, 2}, {GY, 4}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BZ, 3}, {BZ, 5}, {BZ, 4}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RX, 4},
{RX, 5}, {GY, 0}, {GY, 1}, {GY, 2}, {GY, 3}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GX, 4},
{GX, 5}, {GZ, 0}, {GZ, 1}, {GZ, 2}, {GZ, 3}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BX, 4},
{BX, 5}, {BY, 0}, {BY, 1}, {BY, 2}, {BY, 3}, {RY, 0}, {RY, 1}, {RY, 2}, {RY, 3}, {RY, 4},
{RY, 5}, {RZ, 0}, {RZ, 1}, {RZ, 2}, {RZ, 3}, {RZ, 4}, {RZ, 5}, { D, 0}, { D, 1}, { D, 2},
{ D, 3}, { D, 4},
},
{ // Mode 3 (0x02) - 11 5 4 4
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {RW, 8}, {RW, 9}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {GW, 8}, {GW, 9}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {BW, 8}, {BW, 9}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RX, 4},
{RW,10}, {GY, 0}, {GY, 1}, {GY, 2}, {GY, 3}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GW,10},
{BZ, 0}, {GZ, 0}, {GZ, 1}, {GZ, 2}, {GZ, 3}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BW,10},
{BZ, 1}, {BY, 0}, {BY, 1}, {BY, 2}, {BY, 3}, {RY, 0}, {RY, 1}, {RY, 2}, {RY, 3}, {RY, 4},
{BZ, 2}, {RZ, 0}, {RZ, 1}, {RZ, 2}, {RZ, 3}, {RZ, 4}, {BZ, 3}, { D, 0}, { D, 1}, { D, 2},
{ D, 3}, { D, 4},
},
{ // Mode 4 (0x06) - 11 4 5 4
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {RW, 8}, {RW, 9}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {GW, 8}, {GW, 9}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {BW, 8}, {BW, 9}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RW,10},
{GZ, 4}, {GY, 0}, {GY, 1}, {GY, 2}, {GY, 3}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GX, 4},
{GW,10}, {GZ, 0}, {GZ, 1}, {GZ, 2}, {GZ, 3}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BW,10},
{BZ, 1}, {BY, 0}, {BY, 1}, {BY, 2}, {BY, 3}, {RY, 0}, {RY, 1}, {RY, 2}, {RY, 3}, {BZ, 0},
{BZ, 2}, {RZ, 0}, {RZ, 1}, {RZ, 2}, {RZ, 3}, {GY, 4}, {BZ, 3}, { D, 0}, { D, 1}, { D, 2},
{ D, 3}, { D, 4},
},
{ // Mode 5 (0x0a) - 11 4 4 5
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {RW, 8}, {RW, 9}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {GW, 8}, {GW, 9}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {BW, 8}, {BW, 9}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RW,10},
{BY, 4}, {GY, 0}, {GY, 1}, {GY, 2}, {GY, 3}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GW,10},
{BZ, 0}, {GZ, 0}, {GZ, 1}, {GZ, 2}, {GZ, 3}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BX, 4},
{BW,10}, {BY, 0}, {BY, 1}, {BY, 2}, {BY, 3}, {RY, 0}, {RY, 1}, {RY, 2}, {RY, 3}, {BZ, 1},
{BZ, 2}, {RZ, 0}, {RZ, 1}, {RZ, 2}, {RZ, 3}, {BZ, 4}, {BZ, 3}, { D, 0}, { D, 1}, { D, 2},
{ D, 3}, { D, 4},
},
{ // Mode 6 (0x0e) - 9 5 5 5
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {RW, 8}, {BY, 4}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {GW, 8}, {GY, 4}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {BW, 8}, {BZ, 4}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RX, 4},
{GZ, 4}, {GY, 0}, {GY, 1}, {GY, 2}, {GY, 3}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GX, 4},
{BZ, 0}, {GZ, 0}, {GZ, 1}, {GZ, 2}, {GZ, 3}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BX, 4},
{BZ, 1}, {BY, 0}, {BY, 1}, {BY, 2}, {BY, 3}, {RY, 0}, {RY, 1}, {RY, 2}, {RY, 3}, {RY, 4},
{BZ, 2}, {RZ, 0}, {RZ, 1}, {RZ, 2}, {RZ, 3}, {RZ, 4}, {BZ, 3}, { D, 0}, { D, 1}, { D, 2},
{ D, 3}, { D, 4},
},
{ // Mode 7 (0x12) - 8 6 5 5
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {GZ, 4}, {BY, 4}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {BZ, 2}, {GY, 4}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {BZ, 3}, {BZ, 4}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RX, 4},
{RX, 5}, {GY, 0}, {GY, 1}, {GY, 2}, {GY, 3}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GX, 4},
{BZ, 0}, {GZ, 0}, {GZ, 1}, {GZ, 2}, {GZ, 3}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BX, 4},
{BZ, 1}, {BY, 0}, {BY, 1}, {BY, 2}, {BY, 3}, {RY, 0}, {RY, 1}, {RY, 2}, {RY, 3}, {RY, 4},
{RY, 5}, {RZ, 0}, {RZ, 1}, {RZ, 2}, {RZ, 3}, {RZ, 4}, {RZ, 5}, { D, 0}, { D, 1}, { D, 2},
{ D, 3}, { D, 4},
},
{ // Mode 8 (0x16) - 8 5 6 5
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {BZ, 0}, {BY, 4}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {GY, 5}, {GY, 4}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {GZ, 5}, {BZ, 4}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RX, 4},
{GZ, 4}, {GY, 0}, {GY, 1}, {GY, 2}, {GY, 3}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GX, 4},
{GX, 5}, {GZ, 0}, {GZ, 1}, {GZ, 2}, {GZ, 3}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BX, 4},
{BZ, 1}, {BY, 0}, {BY, 1}, {BY, 2}, {BY, 3}, {RY, 0}, {RY, 1}, {RY, 2}, {RY, 3}, {RY, 4},
{BZ, 2}, {RZ, 0}, {RZ, 1}, {RZ, 2}, {RZ, 3}, {RZ, 4}, {BZ, 3}, { D, 0}, { D, 1}, { D, 2},
{ D, 3}, { D, 4},
},
{ // Mode 9 (0x1a) - 8 5 5 6
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {BZ, 1}, {BY, 4}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {BY, 5}, {GY, 4}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {BZ, 5}, {BZ, 4}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RX, 4},
{GZ, 4}, {GY, 0}, {GY, 1}, {GY, 2}, {GY, 3}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GX, 4},
{BZ, 0}, {GZ, 0}, {GZ, 1}, {GZ, 2}, {GZ, 3}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BX, 4},
{BX, 5}, {BY, 0}, {BY, 1}, {BY, 2}, {BY, 3}, {RY, 0}, {RY, 1}, {RY, 2}, {RY, 3}, {RY, 4},
{BZ, 2}, {RZ, 0}, {RZ, 1}, {RZ, 2}, {RZ, 3}, {RZ, 4}, {BZ, 3}, { D, 0}, { D, 1}, { D, 2},
{ D, 3}, { D, 4},
},
{ // Mode 10 (0x1e) - 6 6 6 6
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {GZ, 4}, {BZ, 0}, {BZ, 1}, {BY, 4}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GY, 5}, {BY, 5}, {BZ, 2}, {GY, 4}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {GZ, 5}, {BZ, 3}, {BZ, 5}, {BZ, 4}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RX, 4},
{RX, 5}, {GY, 0}, {GY, 1}, {GY, 2}, {GY, 3}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GX, 4},
{GX, 5}, {GZ, 0}, {GZ, 1}, {GZ, 2}, {GZ, 3}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BX, 4},
{BX, 5}, {BY, 0}, {BY, 1}, {BY, 2}, {BY, 3}, {RY, 0}, {RY, 1}, {RY, 2}, {RY, 3}, {RY, 4},
{RY, 5}, {RZ, 0}, {RZ, 1}, {RZ, 2}, {RZ, 3}, {RZ, 4}, {RZ, 5}, { D, 0}, { D, 1}, { D, 2},
{ D, 3}, { D, 4},
},
{ // Mode 11 (0x03) - 10 10
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {RW, 8}, {RW, 9}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {GW, 8}, {GW, 9}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {BW, 8}, {BW, 9}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RX, 4},
{RX, 5}, {RX, 6}, {RX, 7}, {RX, 8}, {RX, 9}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GX, 4},
{GX, 5}, {GX, 6}, {GX, 7}, {GX, 8}, {GX, 9}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BX, 4},
{BX, 5}, {BX, 6}, {BX, 7}, {BX, 8}, {BX, 9}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0},
{NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0},
{NA, 0}, {NA, 0},
},
{ // Mode 12 (0x07) - 11 9
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {RW, 8}, {RW, 9}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {GW, 8}, {GW, 9}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {BW, 8}, {BW, 9}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RX, 4},
{RX, 5}, {RX, 6}, {RX, 7}, {RX, 8}, {RW,10}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GX, 4},
{GX, 5}, {GX, 6}, {GX, 7}, {GX, 8}, {GW,10}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BX, 4},
{BX, 5}, {BX, 6}, {BX, 7}, {BX, 8}, {BW,10}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0},
{NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0},
{NA, 0}, {NA, 0},
},
{ // Mode 13 (0x0b) - 12 8
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {RW, 8}, {RW, 9}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {GW, 8}, {GW, 9}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {BW, 8}, {BW, 9}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RX, 4},
{RX, 5}, {RX, 6}, {RX, 7}, {RW,11}, {RW,10}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GX, 4},
{GX, 5}, {GX, 6}, {GX, 7}, {GW,11}, {GW,10}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BX, 4},
{BX, 5}, {BX, 6}, {BX, 7}, {BW,11}, {BW,10}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0},
{NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0},
{NA, 0}, {NA, 0},
},
{ // Mode 14 (0x0f) - 16 4
{ M, 0}, { M, 1}, { M, 2}, { M, 3}, { M, 4}, {RW, 0}, {RW, 1}, {RW, 2}, {RW, 3}, {RW, 4},
{RW, 5}, {RW, 6}, {RW, 7}, {RW, 8}, {RW, 9}, {GW, 0}, {GW, 1}, {GW, 2}, {GW, 3}, {GW, 4},
{GW, 5}, {GW, 6}, {GW, 7}, {GW, 8}, {GW, 9}, {BW, 0}, {BW, 1}, {BW, 2}, {BW, 3}, {BW, 4},
{BW, 5}, {BW, 6}, {BW, 7}, {BW, 8}, {BW, 9}, {RX, 0}, {RX, 1}, {RX, 2}, {RX, 3}, {RW,15},
{RW,14}, {RW,13}, {RW,12}, {RW,11}, {RW,10}, {GX, 0}, {GX, 1}, {GX, 2}, {GX, 3}, {GW,15},
{GW,14}, {GW,13}, {GW,12}, {GW,11}, {GW,10}, {BX, 0}, {BX, 1}, {BX, 2}, {BX, 3}, {BW,15},
{BW,14}, {BW,13}, {BW,12}, {BW,11}, {BW,10}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0},
{NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0}, {NA, 0},
{NA, 0}, {NA, 0},
},
};
// Mode, Partitions, Transformed, IndexPrec, RGBAPrec
const D3DX_BC6H::ModeInfo D3DX_BC6H::ms_aInfo[D3DX_BC6H::c_NumModes] =
{
{0x00, 1, true, 3, { { LDRColorA(10,10,10,0), LDRColorA(5, 5, 5,0) }, { LDRColorA(5,5,5,0), LDRColorA(5,5,5,0) } } }, // Mode 1
{0x01, 1, true, 3, { { LDRColorA(7, 7, 7,0), LDRColorA(6, 6, 6,0) }, { LDRColorA(6,6,6,0), LDRColorA(6,6,6,0) } } }, // Mode 2
{0x02, 1, true, 3, { { LDRColorA(11,11,11,0), LDRColorA(5, 4, 4,0) }, { LDRColorA(5,4,4,0), LDRColorA(5,4,4,0) } } }, // Mode 3
{0x06, 1, true, 3, { { LDRColorA(11,11,11,0), LDRColorA(4, 5, 4,0) }, { LDRColorA(4,5,4,0), LDRColorA(4,5,4,0) } } }, // Mode 4
{0x0a, 1, true, 3, { { LDRColorA(11,11,11,0), LDRColorA(4, 4, 5,0) }, { LDRColorA(4,4,5,0), LDRColorA(4,4,5,0) } } }, // Mode 5
{0x0e, 1, true, 3, { { LDRColorA(9, 9, 9,0), LDRColorA(5, 5, 5,0) }, { LDRColorA(5,5,5,0), LDRColorA(5,5,5,0) } } }, // Mode 6
{0x12, 1, true, 3, { { LDRColorA(8, 8, 8,0), LDRColorA(6, 5, 5,0) }, { LDRColorA(6,5,5,0), LDRColorA(6,5,5,0) } } }, // Mode 7
{0x16, 1, true, 3, { { LDRColorA(8, 8, 8,0), LDRColorA(5, 6, 5,0) }, { LDRColorA(5,6,5,0), LDRColorA(5,6,5,0) } } }, // Mode 8
{0x1a, 1, true, 3, { { LDRColorA(8, 8, 8,0), LDRColorA(5, 5, 6,0) }, { LDRColorA(5,5,6,0), LDRColorA(5,5,6,0) } } }, // Mode 9
{0x1e, 1, false, 3, { { LDRColorA(6, 6, 6,0), LDRColorA(6, 6, 6,0) }, { LDRColorA(6,6,6,0), LDRColorA(6,6,6,0) } } }, // Mode 10
{0x03, 0, false, 4, { { LDRColorA(10,10,10,0), LDRColorA(10,10,10,0) }, { LDRColorA(0,0,0,0), LDRColorA(0,0,0,0) } } }, // Mode 11
{0x07, 0, true, 4, { { LDRColorA(11,11,11,0), LDRColorA(9, 9, 9,0) }, { LDRColorA(0,0,0,0), LDRColorA(0,0,0,0) } } }, // Mode 12
{0x0b, 0, true, 4, { { LDRColorA(12,12,12,0), LDRColorA(8, 8, 8,0) }, { LDRColorA(0,0,0,0), LDRColorA(0,0,0,0) } } }, // Mode 13
{0x0f, 0, true, 4, { { LDRColorA(16,16,16,0), LDRColorA(4, 4, 4,0) }, { LDRColorA(0,0,0,0), LDRColorA(0,0,0,0) } } }, // Mode 14
};
const int D3DX_BC6H::ms_aModeToInfo[D3DX_BC6H::c_NumModeInfo] =
{
0, // Mode 1 - 0x00
1, // Mode 2 - 0x01
2, // Mode 3 - 0x02
10, // Mode 11 - 0x03
-1, // Invalid - 0x04
-1, // Invalid - 0x05
3, // Mode 4 - 0x06
11, // Mode 12 - 0x07
-1, // Invalid - 0x08
-1, // Invalid - 0x09
4, // Mode 5 - 0x0a
12, // Mode 13 - 0x0b
-1, // Invalid - 0x0c
-1, // Invalid - 0x0d
5, // Mode 6 - 0x0e
13, // Mode 14 - 0x0f
-1, // Invalid - 0x10
-1, // Invalid - 0x11
6, // Mode 7 - 0x12
-1, // Reserved - 0x13
-1, // Invalid - 0x14
-1, // Invalid - 0x15
7, // Mode 8 - 0x16
-1, // Reserved - 0x17
-1, // Invalid - 0x18
-1, // Invalid - 0x19
8, // Mode 9 - 0x1a
-1, // Reserved - 0x1b
-1, // Invalid - 0x1c
-1, // Invalid - 0x1d
9, // Mode 10 - 0x1e
-1, // Resreved - 0x1f
};
// BC7 compression: uPartitions, uPartitionBits, uPBits, uRotationBits, uIndexModeBits, uIndexPrec, uIndexPrec2, RGBAPrec, RGBAPrecWithP
const D3DX_BC7::ModeInfo D3DX_BC7::ms_aInfo[D3DX_BC7::c_NumModes] =
{
{2, 4, 6, 0, 0, 3, 0, LDRColorA(4,4,4,0), LDRColorA(5,5,5,0)},
// Mode 0: Color only, 3 Subsets, RGBP 4441 (unique P-bit), 3-bit indecies, 16 partitions
{1, 6, 2, 0, 0, 3, 0, LDRColorA(6,6,6,0), LDRColorA(7,7,7,0)},
// Mode 1: Color only, 2 Subsets, RGBP 6661 (shared P-bit), 3-bit indecies, 64 partitions
{2, 6, 0, 0, 0, 2, 0, LDRColorA(5,5,5,0), LDRColorA(5,5,5,0)},
// Mode 2: Color only, 3 Subsets, RGB 555, 2-bit indecies, 64 partitions
{1, 6, 4, 0, 0, 2, 0, LDRColorA(7,7,7,0), LDRColorA(8,8,8,0)},
// Mode 3: Color only, 2 Subsets, RGBP 7771 (unique P-bit), 2-bits indecies, 64 partitions
{0, 0, 0, 2, 1, 2, 3, LDRColorA(5,5,5,6), LDRColorA(5,5,5,6)},
// Mode 4: Color w/ Separate Alpha, 1 Subset, RGB 555, A6, 16x2/16x3-bit indices, 2-bit rotation, 1-bit index selector
{0, 0, 0, 2, 0, 2, 2, LDRColorA(7,7,7,8), LDRColorA(7,7,7,8)},
// Mode 5: Color w/ Separate Alpha, 1 Subset, RGB 777, A8, 16x2/16x2-bit indices, 2-bit rotation
{0, 0, 2, 0, 0, 4, 0, LDRColorA(7,7,7,7), LDRColorA(8,8,8,8)},
// Mode 6: Color+Alpha, 1 Subset, RGBAP 77771 (unique P-bit), 16x4-bit indecies
{1, 6, 4, 0, 0, 2, 0, LDRColorA(5,5,5,5), LDRColorA(6,6,6,6)}
// Mode 7: Color+Alpha, 2 Subsets, RGBAP 55551 (unique P-bit), 2-bit indices, 64 partitions
};
namespace
{
//-------------------------------------------------------------------------------------
// Helper functions
//-------------------------------------------------------------------------------------
inline bool IsFixUpOffset(_In_range_(0, 2) size_t uPartitions, _In_range_(0, 63) size_t uShape, _In_range_(0, 15) size_t uOffset) noexcept
{
assert(uPartitions < 3 && uShape < 64 && uOffset < 16);
_Analysis_assume_(uPartitions < 3 && uShape < 64 && uOffset < 16);
for (size_t p = 0; p <= uPartitions; p++)
{
if (uOffset == g_aFixUp[uPartitions][uShape][p])
{
return true;
}
}
return false;
}
inline void TransformForward(_Inout_updates_all_(BC6H_MAX_REGIONS) INTEndPntPair aEndPts[]) noexcept
{
aEndPts[0].B -= aEndPts[0].A;
aEndPts[1].A -= aEndPts[0].A;
aEndPts[1].B -= aEndPts[0].A;
}
inline void TransformInverse(_Inout_updates_all_(BC6H_MAX_REGIONS) INTEndPntPair aEndPts[], _In_ const LDRColorA& Prec, _In_ bool bSigned) noexcept
{
const INTColor WrapMask((1 << Prec.r) - 1, (1 << Prec.g) - 1, (1 << Prec.b) - 1);
aEndPts[0].B += aEndPts[0].A; aEndPts[0].B &= WrapMask;
aEndPts[1].A += aEndPts[0].A; aEndPts[1].A &= WrapMask;
aEndPts[1].B += aEndPts[0].A; aEndPts[1].B &= WrapMask;
if (bSigned)
{
aEndPts[0].B.SignExtend(Prec);
aEndPts[1].A.SignExtend(Prec);
aEndPts[1].B.SignExtend(Prec);
}
}
inline float Norm(_In_ const INTColor& a, _In_ const INTColor& b) noexcept
{
const float dr = float(a.r) - float(b.r);
const float dg = float(a.g) - float(b.g);
const float db = float(a.b) - float(b.b);
return dr * dr + dg * dg + db * db;
}
// return # of bits needed to store n. handle signed or unsigned cases properly
inline int NBits(_In_ int n, _In_ bool bIsSigned) noexcept
{
int nb;
if (n == 0)
{
return 0; // no bits needed for 0, signed or not
}
else if (n > 0)
{
for (nb = 0; n; ++nb, n >>= 1);
return nb + (bIsSigned ? 1 : 0);
}
else
{
assert(bIsSigned);
for (nb = 0; n < -1; ++nb, n >>= 1);
return nb + 1;
}
}
//-------------------------------------------------------------------------------------
void OptimizeRGB(
_In_reads_(NUM_PIXELS_PER_BLOCK) const HDRColorA* const pPoints,
_Out_ HDRColorA* pX,
_Out_ HDRColorA* pY,
_In_range_(3, 4) uint32_t cSteps,
size_t cPixels,
_In_reads_(cPixels) const size_t* pIndex) noexcept
{
const float *pC = (3 == cSteps) ? pC3 : pC4;
const float *pD = (3 == cSteps) ? pD3 : pD4;
// Find Min and Max points, as starting point
HDRColorA X(FLT_MAX, FLT_MAX, FLT_MAX, 0.0f);
HDRColorA Y(-FLT_MAX, -FLT_MAX, -FLT_MAX, 0.0f);
for (size_t iPoint = 0; iPoint < cPixels; iPoint++)
{
if (pPoints[pIndex[iPoint]].r < X.r) X.r = pPoints[pIndex[iPoint]].r;
if (pPoints[pIndex[iPoint]].g < X.g) X.g = pPoints[pIndex[iPoint]].g;
if (pPoints[pIndex[iPoint]].b < X.b) X.b = pPoints[pIndex[iPoint]].b;
if (pPoints[pIndex[iPoint]].r > Y.r) Y.r = pPoints[pIndex[iPoint]].r;
if (pPoints[pIndex[iPoint]].g > Y.g) Y.g = pPoints[pIndex[iPoint]].g;
if (pPoints[pIndex[iPoint]].b > Y.b) Y.b = pPoints[pIndex[iPoint]].b;
}
// Diagonal axis
HDRColorA AB;
AB.r = Y.r - X.r;
AB.g = Y.g - X.g;
AB.b = Y.b - X.b;
const float fAB = AB.r * AB.r + AB.g * AB.g + AB.b * AB.b;
// Single color block.. no need to root-find
if (fAB < FLT_MIN)
{
pX->r = X.r; pX->g = X.g; pX->b = X.b;
pY->r = Y.r; pY->g = Y.g; pY->b = Y.b;
return;
}
// Try all four axis directions, to determine which diagonal best fits data
const float fABInv = 1.0f / fAB;
HDRColorA Dir;
Dir.r = AB.r * fABInv;
Dir.g = AB.g * fABInv;
Dir.b = AB.b * fABInv;
HDRColorA Mid;
Mid.r = (X.r + Y.r) * 0.5f;
Mid.g = (X.g + Y.g) * 0.5f;
Mid.b = (X.b + Y.b) * 0.5f;
float fDir[4];
fDir[0] = fDir[1] = fDir[2] = fDir[3] = 0.0f;
for (size_t iPoint = 0; iPoint < cPixels; iPoint++)
{
HDRColorA Pt;
Pt.r = (pPoints[pIndex[iPoint]].r - Mid.r) * Dir.r;
Pt.g = (pPoints[pIndex[iPoint]].g - Mid.g) * Dir.g;
Pt.b = (pPoints[pIndex[iPoint]].b - Mid.b) * Dir.b;
float f;
f = Pt.r + Pt.g + Pt.b; fDir[0] += f * f;
f = Pt.r + Pt.g - Pt.b; fDir[1] += f * f;
f = Pt.r - Pt.g + Pt.b; fDir[2] += f * f;
f = Pt.r - Pt.g - Pt.b; fDir[3] += f * f;
}
float fDirMax = fDir[0];
size_t iDirMax = 0;
for (size_t iDir = 1; iDir < 4; iDir++)
{
if (fDir[iDir] > fDirMax)
{
fDirMax = fDir[iDir];
iDirMax = iDir;
}
}
if (iDirMax & 2) std::swap(X.g, Y.g);
if (iDirMax & 1) std::swap(X.b, Y.b);
// Two color block.. no need to root-find
if (fAB < 1.0f / 4096.0f)
{
pX->r = X.r; pX->g = X.g; pX->b = X.b;
pY->r = Y.r; pY->g = Y.g; pY->b = Y.b;
return;
}
// Use Newton's Method to find local minima of sum-of-squares error.
auto const fSteps = static_cast<float>(cSteps - 1);
for (size_t iIteration = 0; iIteration < 8; iIteration++)
{
// Calculate new steps
HDRColorA pSteps[4] = {};
for (size_t iStep = 0; iStep < cSteps; iStep++)
{
pSteps[iStep].r = X.r * pC[iStep] + Y.r * pD[iStep];
pSteps[iStep].g = X.g * pC[iStep] + Y.g * pD[iStep];
pSteps[iStep].b = X.b * pC[iStep] + Y.b * pD[iStep];
}
// Calculate color direction
Dir.r = Y.r - X.r;
Dir.g = Y.g - X.g;
Dir.b = Y.b - X.b;
const float fLen = (Dir.r * Dir.r + Dir.g * Dir.g + Dir.b * Dir.b);
if (fLen < (1.0f / 4096.0f))
break;
const float fScale = fSteps / fLen;
Dir.r *= fScale;
Dir.g *= fScale;
Dir.b *= fScale;
// Evaluate function, and derivatives
float d2X = 0.0f, d2Y = 0.0f;
HDRColorA dX(0.0f, 0.0f, 0.0f, 0.0f), dY(0.0f, 0.0f, 0.0f, 0.0f);
for (size_t iPoint = 0; iPoint < cPixels; iPoint++)
{
const float fDot = (pPoints[pIndex[iPoint]].r - X.r) * Dir.r +
(pPoints[pIndex[iPoint]].g - X.g) * Dir.g +
(pPoints[pIndex[iPoint]].b - X.b) * Dir.b;
uint32_t iStep;
if (fDot <= 0.0f)
iStep = 0;
else if (fDot >= fSteps)
iStep = cSteps - 1;
else
iStep = uint32_t(fDot + 0.5f);
HDRColorA Diff;
Diff.r = pSteps[iStep].r - pPoints[pIndex[iPoint]].r;
Diff.g = pSteps[iStep].g - pPoints[pIndex[iPoint]].g;
Diff.b = pSteps[iStep].b - pPoints[pIndex[iPoint]].b;
const float fC = pC[iStep] * (1.0f / 8.0f);
const float fD = pD[iStep] * (1.0f / 8.0f);
d2X += fC * pC[iStep];
dX.r += fC * Diff.r;
dX.g += fC * Diff.g;
dX.b += fC * Diff.b;
d2Y += fD * pD[iStep];
dY.r += fD * Diff.r;
dY.g += fD * Diff.g;
dY.b += fD * Diff.b;
}
// Move endpoints
if (d2X > 0.0f)
{
const float f = -1.0f / d2X;
X.r += dX.r * f;
X.g += dX.g * f;
X.b += dX.b * f;
}
if (d2Y > 0.0f)
{
const float f = -1.0f / d2Y;
Y.r += dY.r * f;
Y.g += dY.g * f;
Y.b += dY.b * f;
}
if ((dX.r * dX.r < fEpsilon) && (dX.g * dX.g < fEpsilon) && (dX.b * dX.b < fEpsilon) &&
(dY.r * dY.r < fEpsilon) && (dY.g * dY.g < fEpsilon) && (dY.b * dY.b < fEpsilon))
{
break;
}
}
pX->r = X.r; pX->g = X.g; pX->b = X.b;
pY->r = Y.r; pY->g = Y.g; pY->b = Y.b;
}
//-------------------------------------------------------------------------------------
void OptimizeRGBA(
_In_reads_(NUM_PIXELS_PER_BLOCK) const HDRColorA* const pPoints,
_Out_ HDRColorA* pX,
_Out_ HDRColorA* pY,
_In_range_(3, 4) uint32_t cSteps,
size_t cPixels,
_In_reads_(cPixels) const size_t* pIndex) noexcept
{
const float *pC = (3 == cSteps) ? pC3 : pC4;
const float *pD = (3 == cSteps) ? pD3 : pD4;
// Find Min and Max points, as starting point
HDRColorA X(1.0f, 1.0f, 1.0f, 1.0f);
HDRColorA Y(0.0f, 0.0f, 0.0f, 0.0f);
for (size_t iPoint = 0; iPoint < cPixels; iPoint++)
{
if (pPoints[pIndex[iPoint]].r < X.r) X.r = pPoints[pIndex[iPoint]].r;
if (pPoints[pIndex[iPoint]].g < X.g) X.g = pPoints[pIndex[iPoint]].g;
if (pPoints[pIndex[iPoint]].b < X.b) X.b = pPoints[pIndex[iPoint]].b;
if (pPoints[pIndex[iPoint]].a < X.a) X.a = pPoints[pIndex[iPoint]].a;
if (pPoints[pIndex[iPoint]].r > Y.r) Y.r = pPoints[pIndex[iPoint]].r;
if (pPoints[pIndex[iPoint]].g > Y.g) Y.g = pPoints[pIndex[iPoint]].g;
if (pPoints[pIndex[iPoint]].b > Y.b) Y.b = pPoints[pIndex[iPoint]].b;
if (pPoints[pIndex[iPoint]].a > Y.a) Y.a = pPoints[pIndex[iPoint]].a;
}
// Diagonal axis
const HDRColorA AB = Y - X;
const float fAB = AB * AB;
// Single color block.. no need to root-find
if (fAB < FLT_MIN)
{
*pX = X;
*pY = Y;
return;
}
// Try all four axis directions, to determine which diagonal best fits data
const float fABInv = 1.0f / fAB;
HDRColorA Dir = AB * fABInv;
const HDRColorA Mid = (X + Y) * 0.5f;
float fDir[8];
fDir[0] = fDir[1] = fDir[2] = fDir[3] = fDir[4] = fDir[5] = fDir[6] = fDir[7] = 0.0f;
for (size_t iPoint = 0; iPoint < cPixels; iPoint++)
{
HDRColorA Pt;
Pt.r = (pPoints[pIndex[iPoint]].r - Mid.r) * Dir.r;
Pt.g = (pPoints[pIndex[iPoint]].g - Mid.g) * Dir.g;
Pt.b = (pPoints[pIndex[iPoint]].b - Mid.b) * Dir.b;
Pt.a = (pPoints[pIndex[iPoint]].a - Mid.a) * Dir.a;
float f;
f = Pt.r + Pt.g + Pt.b + Pt.a; fDir[0] += f * f;
f = Pt.r + Pt.g + Pt.b - Pt.a; fDir[1] += f * f;
f = Pt.r + Pt.g - Pt.b + Pt.a; fDir[2] += f * f;
f = Pt.r + Pt.g - Pt.b - Pt.a; fDir[3] += f * f;
f = Pt.r - Pt.g + Pt.b + Pt.a; fDir[4] += f * f;
f = Pt.r - Pt.g + Pt.b - Pt.a; fDir[5] += f * f;
f = Pt.r - Pt.g - Pt.b + Pt.a; fDir[6] += f * f;
f = Pt.r - Pt.g - Pt.b - Pt.a; fDir[7] += f * f;
}
float fDirMax = fDir[0];
size_t iDirMax = 0;
for (size_t iDir = 1; iDir < 8; iDir++)
{
if (fDir[iDir] > fDirMax)
{
fDirMax = fDir[iDir];
iDirMax = iDir;
}
}
if (iDirMax & 4) std::swap(X.g, Y.g);
if (iDirMax & 2) std::swap(X.b, Y.b);
if (iDirMax & 1) std::swap(X.a, Y.a);
// Two color block.. no need to root-find
if (fAB < 1.0f / 4096.0f)
{
*pX = X;
*pY = Y;
return;
}
// Use Newton's Method to find local minima of sum-of-squares error.
const auto fSteps = static_cast<float>(cSteps - 1u);
for (size_t iIteration = 0; iIteration < 8; iIteration++)
{
// Calculate new steps
HDRColorA pSteps[BC7_MAX_INDICES];
LDRColorA lX, lY;
lX = (X * 255.0f).ToLDRColorA();
lY = (Y * 255.0f).ToLDRColorA();
for (size_t iStep = 0; iStep < cSteps; iStep++)
{
pSteps[iStep] = X * pC[iStep] + Y * pD[iStep];
//LDRColorA::Interpolate(lX, lY, i, i, wcprec, waprec, aSteps[i]);
}
// Calculate color direction
Dir = Y - X;
const float fLen = Dir * Dir;
if (fLen < (1.0f / 4096.0f))
break;
const float fScale = fSteps / fLen;
Dir *= fScale;
// Evaluate function, and derivatives
float d2X = 0.0f, d2Y = 0.0f;
HDRColorA dX(0.0f, 0.0f, 0.0f, 0.0f), dY(0.0f, 0.0f, 0.0f, 0.0f);
for (size_t iPoint = 0; iPoint < cPixels; ++iPoint)
{
const float fDot = (pPoints[pIndex[iPoint]] - X) * Dir;
uint32_t iStep;
if (fDot <= 0.0f)
iStep = 0;
else if (fDot >= fSteps)
iStep = cSteps - 1;
else
iStep = uint32_t(fDot + 0.5f);
const HDRColorA Diff = pSteps[iStep] - pPoints[pIndex[iPoint]];
const float fC = pC[iStep] * (1.0f / 8.0f);
const float fD = pD[iStep] * (1.0f / 8.0f);
d2X += fC * pC[iStep];
dX += Diff * fC;
d2Y += fD * pD[iStep];
dY += Diff * fD;
}
// Move endpoints
if (d2X > 0.0f)
{
const float f = -1.0f / d2X;
X += dX * f;
}
if (d2Y > 0.0f)
{
const float f = -1.0f / d2Y;
Y += dY * f;
}
if ((dX * dX < fEpsilon) && (dY * dY < fEpsilon))
break;
}
*pX = X;
*pY = Y;
}
//-------------------------------------------------------------------------------------
float ComputeError(
_Inout_ const LDRColorA& pixel,
_In_reads_(1 << uIndexPrec) const LDRColorA aPalette[],
uint8_t uIndexPrec,
uint8_t uIndexPrec2,
_Out_opt_ size_t* pBestIndex = nullptr,
_Out_opt_ size_t* pBestIndex2 = nullptr) noexcept
{
const size_t uNumIndices = size_t(1) << uIndexPrec;
const size_t uNumIndices2 = size_t(1) << uIndexPrec2;
float fTotalErr = 0;
float fBestErr = FLT_MAX;
if (pBestIndex)
*pBestIndex = 0;
if (pBestIndex2)
*pBestIndex2 = 0;
const XMVECTOR vpixel = XMLoadUByte4(reinterpret_cast<const XMUBYTE4*>(&pixel));
if (uIndexPrec2 == 0)
{
for (size_t i = 0; i < uNumIndices && fBestErr > 0; i++)
{
XMVECTOR tpixel = XMLoadUByte4(reinterpret_cast<const XMUBYTE4*>(&aPalette[i]));
// Compute ErrorMetric
tpixel = XMVectorSubtract(vpixel, tpixel);
const float fErr = XMVectorGetX(XMVector4Dot(tpixel, tpixel));
if (fErr > fBestErr) // error increased, so we're done searching
break;
if (fErr < fBestErr)
{
fBestErr = fErr;
if (pBestIndex)
*pBestIndex = i;
}
}
fTotalErr += fBestErr;
}
else
{
for (size_t i = 0; i < uNumIndices && fBestErr > 0; i++)
{
XMVECTOR tpixel = XMLoadUByte4(reinterpret_cast<const XMUBYTE4*>(&aPalette[i]));
// Compute ErrorMetricRGB
tpixel = XMVectorSubtract(vpixel, tpixel);
const float fErr = XMVectorGetX(XMVector3Dot(tpixel, tpixel));
if (fErr > fBestErr) // error increased, so we're done searching
break;
if (fErr < fBestErr)
{
fBestErr = fErr;
if (pBestIndex)
*pBestIndex = i;
}
}
fTotalErr += fBestErr;
fBestErr = FLT_MAX;
for (size_t i = 0; i < uNumIndices2 && fBestErr > 0; i++)
{
// Compute ErrorMetricAlpha
const float ea = float(pixel.a) - float(aPalette[i].a);
const float fErr = ea*ea;
if (fErr > fBestErr) // error increased, so we're done searching
break;
if (fErr < fBestErr)
{
fBestErr = fErr;
if (pBestIndex2)
*pBestIndex2 = i;
}
}
fTotalErr += fBestErr;
}
return fTotalErr;
}
void FillWithErrorColors(_Out_writes_(NUM_PIXELS_PER_BLOCK) HDRColorA* pOut) noexcept
{
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
{
#ifdef _DEBUG
// Use Magenta in debug as a highly-visible error color
pOut[i] = HDRColorA(1.0f, 0.0f, 1.0f, 1.0f);
#else
// In production use, default to black
pOut[i] = HDRColorA(0.0f, 0.0f, 0.0f, 1.0f);
#endif
}
}
}
//-------------------------------------------------------------------------------------
// BC6H Compression
//-------------------------------------------------------------------------------------
_Use_decl_annotations_
void D3DX_BC6H::Decode(bool bSigned, HDRColorA* pOut) const noexcept
{
assert(pOut);
size_t uStartBit = 0;
uint8_t uMode = GetBits(uStartBit, 2u);
if (uMode != 0x00 && uMode != 0x01)
{
uMode = static_cast<uint8_t>((unsigned(GetBits(uStartBit, 3)) << 2) | uMode);
}
assert(uMode < c_NumModeInfo);
_Analysis_assume_(uMode < c_NumModeInfo);
if (ms_aModeToInfo[uMode] >= 0)
{
assert(static_cast<unsigned int>(ms_aModeToInfo[uMode]) < c_NumModes);
_Analysis_assume_(ms_aModeToInfo[uMode] < c_NumModes);
const ModeDescriptor* desc = ms_aDesc[ms_aModeToInfo[uMode]];
const ModeInfo& info = ms_aInfo[ms_aModeToInfo[uMode]];
INTEndPntPair aEndPts[BC6H_MAX_REGIONS] = {};
uint32_t uShape = 0;
// Read header
const size_t uHeaderBits = info.uPartitions > 0 ? 82u : 65u;
while (uStartBit < uHeaderBits)
{
const size_t uCurBit = uStartBit;
if (GetBit(uStartBit))
{
switch (desc[uCurBit].m_eField)
{
case D: uShape |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case RW: aEndPts[0].A.r |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case RX: aEndPts[0].B.r |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case RY: aEndPts[1].A.r |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case RZ: aEndPts[1].B.r |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case GW: aEndPts[0].A.g |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case GX: aEndPts[0].B.g |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case GY: aEndPts[1].A.g |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case GZ: aEndPts[1].B.g |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case BW: aEndPts[0].A.b |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case BX: aEndPts[0].B.b |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case BY: aEndPts[1].A.b |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
case BZ: aEndPts[1].B.b |= 1 << uint32_t(desc[uCurBit].m_uBit); break;
default:
{
#if defined(_WIN32) && defined(_DEBUG)
OutputDebugStringA("BC6H: Invalid header bits encountered during decoding\n");
#endif
FillWithErrorColors(pOut);
return;
}
}
}
}
assert(uShape < 64);
_Analysis_assume_(uShape < 64);
// Sign extend necessary end points
if (bSigned)
{
aEndPts[0].A.SignExtend(info.RGBAPrec[0][0]);
}
if (bSigned || info.bTransformed)
{
assert(info.uPartitions < BC6H_MAX_REGIONS);
_Analysis_assume_(info.uPartitions < BC6H_MAX_REGIONS);
for (size_t p = 0; p <= info.uPartitions; ++p)
{
if (p != 0)
{
aEndPts[p].A.SignExtend(info.RGBAPrec[p][0]);
}
aEndPts[p].B.SignExtend(info.RGBAPrec[p][1]);
}
}
// Inverse transform the end points
if (info.bTransformed)
{
TransformInverse(aEndPts, info.RGBAPrec[0][0], bSigned);
}
// Read indices
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
{
const size_t uNumBits = IsFixUpOffset(info.uPartitions, uShape, i) ? info.uIndexPrec - 1u : info.uIndexPrec;
if (uStartBit + uNumBits > 128)
{
#if defined(_WIN32) && defined(_DEBUG)
OutputDebugStringA("BC6H: Invalid block encountered during decoding\n");
#endif
FillWithErrorColors(pOut);
return;
}
const uint8_t uIndex = GetBits(uStartBit, uNumBits);
if (uIndex >= ((info.uPartitions > 0) ? 8 : 16))
{
#if defined(_WIN32) && defined(_DEBUG)
OutputDebugStringA("BC6H: Invalid index encountered during decoding\n");
#endif
FillWithErrorColors(pOut);
return;
}
const size_t uRegion = g_aPartitionTable[info.uPartitions][uShape][i];
assert(uRegion < BC6H_MAX_REGIONS);
_Analysis_assume_(uRegion < BC6H_MAX_REGIONS);
// Unquantize endpoints and interpolate
const int r1 = Unquantize(aEndPts[uRegion].A.r, info.RGBAPrec[0][0].r, bSigned);
const int g1 = Unquantize(aEndPts[uRegion].A.g, info.RGBAPrec[0][0].g, bSigned);
const int b1 = Unquantize(aEndPts[uRegion].A.b, info.RGBAPrec[0][0].b, bSigned);
const int r2 = Unquantize(aEndPts[uRegion].B.r, info.RGBAPrec[0][0].r, bSigned);
const int g2 = Unquantize(aEndPts[uRegion].B.g, info.RGBAPrec[0][0].g, bSigned);
const int b2 = Unquantize(aEndPts[uRegion].B.b, info.RGBAPrec[0][0].b, bSigned);
const int* aWeights = info.uPartitions > 0 ? g_aWeights3 : g_aWeights4;
INTColor fc;
fc.r = FinishUnquantize((r1 * (BC67_WEIGHT_MAX - aWeights[uIndex]) + r2 * aWeights[uIndex] + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT, bSigned);
fc.g = FinishUnquantize((g1 * (BC67_WEIGHT_MAX - aWeights[uIndex]) + g2 * aWeights[uIndex] + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT, bSigned);
fc.b = FinishUnquantize((b1 * (BC67_WEIGHT_MAX - aWeights[uIndex]) + b2 * aWeights[uIndex] + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT, bSigned);
HALF rgb[3];
fc.ToF16(rgb, bSigned);
pOut[i].r = XMConvertHalfToFloat(rgb[0]);
pOut[i].g = XMConvertHalfToFloat(rgb[1]);
pOut[i].b = XMConvertHalfToFloat(rgb[2]);
pOut[i].a = 1.0f;
}
}
else
{
#if defined(_WIN32) && defined(_DEBUG)
const char* warnstr = "BC6H: Invalid mode encountered during decoding\n";
switch (uMode)
{
case 0x13: warnstr = "BC6H: Reserved mode 10011 encountered during decoding\n"; break;
case 0x17: warnstr = "BC6H: Reserved mode 10111 encountered during decoding\n"; break;
case 0x1B: warnstr = "BC6H: Reserved mode 11011 encountered during decoding\n"; break;
case 0x1F: warnstr = "BC6H: Reserved mode 11111 encountered during decoding\n"; break;
default: break;
}
OutputDebugStringA(warnstr);
#endif
// Per the BC6H format spec, we must return opaque black
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
{
pOut[i] = HDRColorA(0.0f, 0.0f, 0.0f, 1.0f);
}
}
}
_Use_decl_annotations_
void D3DX_BC6H::Encode(bool bSigned, const HDRColorA* const pIn) noexcept
{
assert(pIn);
EncodeParams EP(pIn, bSigned);
for (EP.uMode = 0; EP.uMode < c_NumModes && EP.fBestErr > 0; ++EP.uMode)
{
const uint8_t uShapes = ms_aInfo[EP.uMode].uPartitions ? 32u : 1u;
// Number of rough cases to look at. reasonable values of this are 1, uShapes/4, and uShapes
// uShapes/4 gets nearly all the cases; you can increase that a bit (say by 3 or 4) if you really want to squeeze the last bit out
const size_t uItems = std::max<size_t>(1u, size_t(uShapes >> 2));
float afRoughMSE[BC6H_MAX_SHAPES];
uint8_t auShape[BC6H_MAX_SHAPES];
// pick the best uItems shapes and refine these.
for (EP.uShape = 0; EP.uShape < uShapes; ++EP.uShape)
{
size_t uShape = EP.uShape;
afRoughMSE[uShape] = RoughMSE(&EP);
auShape[uShape] = static_cast<uint8_t>(uShape);
}
// Bubble up the first uItems items
for (size_t i = 0; i < uItems; i++)
{
for (size_t j = i + 1; j < uShapes; j++)
{
if (afRoughMSE[i] > afRoughMSE[j])
{
std::swap(afRoughMSE[i], afRoughMSE[j]);
std::swap(auShape[i], auShape[j]);
}
}
}
for (size_t i = 0; i < uItems && EP.fBestErr > 0; i++)
{
EP.uShape = auShape[i];
Refine(&EP);
}
}
}
//-------------------------------------------------------------------------------------
_Use_decl_annotations_
int D3DX_BC6H::Quantize(int iValue, int prec, bool bSigned) noexcept
{
assert(prec > 1); // didn't bother to make it work for 1
int q, s = 0;
if (bSigned)
{
assert(iValue >= -F16MAX && iValue <= F16MAX);
if (iValue < 0)
{
s = 1;
iValue = -iValue;
}
q = (prec >= 16) ? iValue : (iValue << (prec - 1)) / (F16MAX + 1);
if (s)
q = -q;
assert(q > -(1 << (prec - 1)) && q < (1 << (prec - 1)));
}
else
{
assert(iValue >= 0 && iValue <= F16MAX);
q = (prec >= 15) ? iValue : (iValue << prec) / (F16MAX + 1);
assert(q >= 0 && q < (1 << prec));
}
return q;
}
_Use_decl_annotations_
int D3DX_BC6H::Unquantize(int comp, uint8_t uBitsPerComp, bool bSigned) noexcept
{
int unq = 0, s = 0;
if (bSigned)
{
if (uBitsPerComp >= 16)
{
unq = comp;
}
else
{
if (comp < 0)
{
s = 1;
comp = -comp;
}
if (comp == 0) unq = 0;
else if (comp >= ((1 << (uBitsPerComp - 1)) - 1)) unq = 0x7FFF;
else unq = ((comp << 15) + 0x4000) >> (uBitsPerComp - 1);
if (s) unq = -unq;
}
}
else
{
if (uBitsPerComp >= 15) unq = comp;
else if (comp == 0) unq = 0;
else if (comp == ((1 << uBitsPerComp) - 1)) unq = 0xFFFF;
else unq = ((comp << 16) + 0x8000) >> uBitsPerComp;
}
return unq;
}
_Use_decl_annotations_
int D3DX_BC6H::FinishUnquantize(int comp, bool bSigned) noexcept
{
if (bSigned)
{
return (comp < 0) ? -(((-comp) * 31) >> 5) : (comp * 31) >> 5; // scale the magnitude by 31/32
}
else
{
return (comp * 31) >> 6; // scale the magnitude by 31/64
}
}
//-------------------------------------------------------------------------------------
_Use_decl_annotations_
bool D3DX_BC6H::EndPointsFit(const EncodeParams* pEP, const INTEndPntPair aEndPts[]) noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const bool bTransformed = ms_aInfo[pEP->uMode].bTransformed;
const bool bIsSigned = pEP->bSigned;
const LDRColorA& Prec0 = ms_aInfo[pEP->uMode].RGBAPrec[0][0];
const LDRColorA& Prec1 = ms_aInfo[pEP->uMode].RGBAPrec[0][1];
const LDRColorA& Prec2 = ms_aInfo[pEP->uMode].RGBAPrec[1][0];
const LDRColorA& Prec3 = ms_aInfo[pEP->uMode].RGBAPrec[1][1];
INTColor aBits[4];
aBits[0].r = NBits(aEndPts[0].A.r, bIsSigned);
aBits[0].g = NBits(aEndPts[0].A.g, bIsSigned);
aBits[0].b = NBits(aEndPts[0].A.b, bIsSigned);
aBits[1].r = NBits(aEndPts[0].B.r, bTransformed || bIsSigned);
aBits[1].g = NBits(aEndPts[0].B.g, bTransformed || bIsSigned);
aBits[1].b = NBits(aEndPts[0].B.b, bTransformed || bIsSigned);
if (aBits[0].r > Prec0.r || aBits[1].r > Prec1.r ||
aBits[0].g > Prec0.g || aBits[1].g > Prec1.g ||
aBits[0].b > Prec0.b || aBits[1].b > Prec1.b)
return false;
if (ms_aInfo[pEP->uMode].uPartitions)
{
aBits[2].r = NBits(aEndPts[1].A.r, bTransformed || bIsSigned);
aBits[2].g = NBits(aEndPts[1].A.g, bTransformed || bIsSigned);
aBits[2].b = NBits(aEndPts[1].A.b, bTransformed || bIsSigned);
aBits[3].r = NBits(aEndPts[1].B.r, bTransformed || bIsSigned);
aBits[3].g = NBits(aEndPts[1].B.g, bTransformed || bIsSigned);
aBits[3].b = NBits(aEndPts[1].B.b, bTransformed || bIsSigned);
if (aBits[2].r > Prec2.r || aBits[3].r > Prec3.r ||
aBits[2].g > Prec2.g || aBits[3].g > Prec3.g ||
aBits[2].b > Prec2.b || aBits[3].b > Prec3.b)
return false;
}
return true;
}
_Use_decl_annotations_
void D3DX_BC6H::GeneratePaletteQuantized(const EncodeParams* pEP, const INTEndPntPair& endPts, INTColor aPalette[]) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const size_t uIndexPrec = ms_aInfo[pEP->uMode].uIndexPrec;
const size_t uNumIndices = size_t(1) << uIndexPrec;
assert(uNumIndices > 0);
_Analysis_assume_(uNumIndices > 0);
const LDRColorA& Prec = ms_aInfo[pEP->uMode].RGBAPrec[0][0];
// scale endpoints
INTEndPntPair unqEndPts;
unqEndPts.A.r = Unquantize(endPts.A.r, Prec.r, pEP->bSigned);
unqEndPts.A.g = Unquantize(endPts.A.g, Prec.g, pEP->bSigned);
unqEndPts.A.b = Unquantize(endPts.A.b, Prec.b, pEP->bSigned);
unqEndPts.B.r = Unquantize(endPts.B.r, Prec.r, pEP->bSigned);
unqEndPts.B.g = Unquantize(endPts.B.g, Prec.g, pEP->bSigned);
unqEndPts.B.b = Unquantize(endPts.B.b, Prec.b, pEP->bSigned);
// interpolate
const int* aWeights = nullptr;
switch (uIndexPrec)
{
case 3: aWeights = g_aWeights3; assert(uNumIndices <= 8); _Analysis_assume_(uNumIndices <= 8); break;
case 4: aWeights = g_aWeights4; assert(uNumIndices <= 16); _Analysis_assume_(uNumIndices <= 16); break;
default:
assert(false);
for (size_t i = 0; i < uNumIndices; ++i)
{
#pragma prefast(suppress:22102 22103, "writing blocks in two halves confuses tool")
aPalette[i] = INTColor(0, 0, 0);
}
return;
}
for (size_t i = 0; i < uNumIndices; ++i)
{
aPalette[i].r = FinishUnquantize(
(unqEndPts.A.r * (BC67_WEIGHT_MAX - aWeights[i]) + unqEndPts.B.r * aWeights[i] + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT,
pEP->bSigned);
aPalette[i].g = FinishUnquantize(
(unqEndPts.A.g * (BC67_WEIGHT_MAX - aWeights[i]) + unqEndPts.B.g * aWeights[i] + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT,
pEP->bSigned);
aPalette[i].b = FinishUnquantize(
(unqEndPts.A.b * (BC67_WEIGHT_MAX - aWeights[i]) + unqEndPts.B.b * aWeights[i] + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT,
pEP->bSigned);
}
}
// given a collection of colors and quantized endpoints, generate a palette, choose best entries, and return a single toterr
_Use_decl_annotations_
float D3DX_BC6H::MapColorsQuantized(const EncodeParams* pEP, const INTColor aColors[], size_t np, const INTEndPntPair &endPts) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const uint8_t uIndexPrec = ms_aInfo[pEP->uMode].uIndexPrec;
auto const uNumIndices = static_cast<const uint8_t>(1u << uIndexPrec);
INTColor aPalette[BC6H_MAX_INDICES];
GeneratePaletteQuantized(pEP, endPts, aPalette);
float fTotErr = 0;
for (size_t i = 0; i < np; ++i)
{
const XMVECTOR vcolors = XMLoadSInt4(reinterpret_cast<const XMINT4*>(&aColors[i]));
// Compute ErrorMetricRGB
XMVECTOR tpal = XMLoadSInt4(reinterpret_cast<const XMINT4*>(&aPalette[0]));
tpal = XMVectorSubtract(vcolors, tpal);
float fBestErr = XMVectorGetX(XMVector3Dot(tpal, tpal));
for (int j = 1; j < uNumIndices && fBestErr > 0; ++j)
{
// Compute ErrorMetricRGB
tpal = XMLoadSInt4(reinterpret_cast<const XMINT4*>(&aPalette[j]));
tpal = XMVectorSubtract(vcolors, tpal);
const float fErr = XMVectorGetX(XMVector3Dot(tpal, tpal));
if (fErr > fBestErr) break; // error increased, so we're done searching
if (fErr < fBestErr) fBestErr = fErr;
}
fTotErr += fBestErr;
}
return fTotErr;
}
_Use_decl_annotations_
float D3DX_BC6H::PerturbOne(const EncodeParams* pEP, const INTColor aColors[], size_t np, uint8_t ch,
const INTEndPntPair& oldEndPts, INTEndPntPair& newEndPts, float fOldErr, int do_b) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
uint8_t uPrec;
switch (ch)
{
case 0: uPrec = ms_aInfo[pEP->uMode].RGBAPrec[0][0].r; break;
case 1: uPrec = ms_aInfo[pEP->uMode].RGBAPrec[0][0].g; break;
case 2: uPrec = ms_aInfo[pEP->uMode].RGBAPrec[0][0].b; break;
default: assert(false); newEndPts = oldEndPts; return FLT_MAX;
}
INTEndPntPair tmpEndPts;
float fMinErr = fOldErr;
int beststep = 0;
// copy real endpoints so we can perturb them
tmpEndPts = newEndPts = oldEndPts;
// do a logarithmic search for the best error for this endpoint (which)
for (int step = 1 << (uPrec - 1); step; step >>= 1)
{
bool bImproved = false;
for (int sign = -1; sign <= 1; sign += 2)
{
if (do_b == 0)
{
tmpEndPts.A[ch] = newEndPts.A[ch] + sign * step;
if (tmpEndPts.A[ch] < 0 || tmpEndPts.A[ch] >= (1 << uPrec))
continue;
}
else
{
tmpEndPts.B[ch] = newEndPts.B[ch] + sign * step;
if (tmpEndPts.B[ch] < 0 || tmpEndPts.B[ch] >= (1 << uPrec))
continue;
}
const float fErr = MapColorsQuantized(pEP, aColors, np, tmpEndPts);
if (fErr < fMinErr)
{
bImproved = true;
fMinErr = fErr;
beststep = sign * step;
}
}
// if this was an improvement, move the endpoint and continue search from there
if (bImproved)
{
if (do_b == 0)
newEndPts.A[ch] += beststep;
else
newEndPts.B[ch] += beststep;
}
}
return fMinErr;
}
_Use_decl_annotations_
void D3DX_BC6H::OptimizeOne(const EncodeParams* pEP, const INTColor aColors[], size_t np, float aOrgErr,
const INTEndPntPair &aOrgEndPts, INTEndPntPair &aOptEndPts) const noexcept
{
assert(pEP);
float aOptErr = aOrgErr;
aOptEndPts.A = aOrgEndPts.A;
aOptEndPts.B = aOrgEndPts.B;
INTEndPntPair new_a, new_b;
INTEndPntPair newEndPts;
int do_b;
// now optimize each channel separately
for (uint8_t ch = 0; ch < BC6H_NUM_CHANNELS; ++ch)
{
// figure out which endpoint when perturbed gives the most improvement and start there
// if we just alternate, we can easily end up in a local minima
const float fErr0 = PerturbOne(pEP, aColors, np, ch, aOptEndPts, new_a, aOptErr, 0); // perturb endpt A
const float fErr1 = PerturbOne(pEP, aColors, np, ch, aOptEndPts, new_b, aOptErr, 1); // perturb endpt B
if (fErr0 < fErr1)
{
if (fErr0 >= aOptErr) continue;
aOptEndPts.A[ch] = new_a.A[ch];
aOptErr = fErr0;
do_b = 1; // do B next
}
else
{
if (fErr1 >= aOptErr) continue;
aOptEndPts.B[ch] = new_b.B[ch];
aOptErr = fErr1;
do_b = 0; // do A next
}
// now alternate endpoints and keep trying until there is no improvement
for (;;)
{
const float fErr = PerturbOne(pEP, aColors, np, ch, aOptEndPts, newEndPts, aOptErr, do_b);
if (fErr >= aOptErr)
break;
if (do_b == 0)
aOptEndPts.A[ch] = newEndPts.A[ch];
else
aOptEndPts.B[ch] = newEndPts.B[ch];
aOptErr = fErr;
do_b = 1 - do_b; // now move the other endpoint
}
}
}
_Use_decl_annotations_
void D3DX_BC6H::OptimizeEndPoints(const EncodeParams* pEP, const float aOrgErr[], const INTEndPntPair aOrgEndPts[], INTEndPntPair aOptEndPts[]) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const uint8_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
assert(uPartitions < BC6H_MAX_REGIONS);
_Analysis_assume_(uPartitions < BC6H_MAX_REGIONS);
INTColor aPixels[NUM_PIXELS_PER_BLOCK];
for (size_t p = 0; p <= uPartitions; ++p)
{
// collect the pixels in the region
size_t np = 0;
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
{
if (g_aPartitionTable[p][pEP->uShape][i] == p)
{
aPixels[np++] = pEP->aIPixels[i];
}
}
OptimizeOne(pEP, aPixels, np, aOrgErr[p], aOrgEndPts[p], aOptEndPts[p]);
}
}
// Swap endpoints as needed to ensure that the indices at fix up have a 0 high-order bit
_Use_decl_annotations_
void D3DX_BC6H::SwapIndices(const EncodeParams* pEP, INTEndPntPair aEndPts[], size_t aIndices[]) noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const size_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
const size_t uNumIndices = size_t(1) << ms_aInfo[pEP->uMode].uIndexPrec;
const size_t uHighIndexBit = uNumIndices >> 1;
assert(uPartitions < BC6H_MAX_REGIONS && pEP->uShape < BC6H_MAX_SHAPES);
_Analysis_assume_(uPartitions < BC6H_MAX_REGIONS && pEP->uShape < BC6H_MAX_SHAPES);
for (size_t p = 0; p <= uPartitions; ++p)
{
const size_t i = g_aFixUp[uPartitions][pEP->uShape][p];
assert(g_aPartitionTable[uPartitions][pEP->uShape][i] == p);
if (aIndices[i] & uHighIndexBit)
{
// high bit is set, swap the aEndPts and indices for this region
std::swap(aEndPts[p].A, aEndPts[p].B);
for (size_t j = 0; j < NUM_PIXELS_PER_BLOCK; ++j)
if (g_aPartitionTable[uPartitions][pEP->uShape][j] == p)
aIndices[j] = uNumIndices - 1 - aIndices[j];
}
}
}
// assign indices given a tile, shape, and quantized endpoints, return toterr for each region
_Use_decl_annotations_
void D3DX_BC6H::AssignIndices(const EncodeParams* pEP, const INTEndPntPair aEndPts[], size_t aIndices[], float aTotErr[]) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const uint8_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
auto const uNumIndices = static_cast<const uint8_t>(1u << ms_aInfo[pEP->uMode].uIndexPrec);
assert(uPartitions < BC6H_MAX_REGIONS && pEP->uShape < BC6H_MAX_SHAPES);
_Analysis_assume_(uPartitions < BC6H_MAX_REGIONS && pEP->uShape < BC6H_MAX_SHAPES);
// build list of possibles
INTColor aPalette[BC6H_MAX_REGIONS][BC6H_MAX_INDICES];
for (size_t p = 0; p <= uPartitions; ++p)
{
GeneratePaletteQuantized(pEP, aEndPts[p], aPalette[p]);
aTotErr[p] = 0;
}
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
{
const uint8_t uRegion = g_aPartitionTable[uPartitions][pEP->uShape][i];
assert(uRegion < BC6H_MAX_REGIONS);
_Analysis_assume_(uRegion < BC6H_MAX_REGIONS);
float fBestErr = Norm(pEP->aIPixels[i], aPalette[uRegion][0]);
aIndices[i] = 0;
for (uint8_t j = 1; j < uNumIndices && fBestErr > 0; ++j)
{
const float fErr = Norm(pEP->aIPixels[i], aPalette[uRegion][j]);
if (fErr > fBestErr) break; // error increased, so we're done searching
if (fErr < fBestErr)
{
fBestErr = fErr;
aIndices[i] = j;
}
}
aTotErr[uRegion] += fBestErr;
}
}
_Use_decl_annotations_
void D3DX_BC6H::QuantizeEndPts(const EncodeParams* pEP, INTEndPntPair* aQntEndPts) const noexcept
{
assert(pEP && aQntEndPts);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const INTEndPntPair* aUnqEndPts = pEP->aUnqEndPts[pEP->uShape];
const LDRColorA& Prec = ms_aInfo[pEP->uMode].RGBAPrec[0][0];
const uint8_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
assert(uPartitions < BC6H_MAX_REGIONS);
_Analysis_assume_(uPartitions < BC6H_MAX_REGIONS);
for (size_t p = 0; p <= uPartitions; ++p)
{
aQntEndPts[p].A.r = Quantize(aUnqEndPts[p].A.r, Prec.r, pEP->bSigned);
aQntEndPts[p].A.g = Quantize(aUnqEndPts[p].A.g, Prec.g, pEP->bSigned);
aQntEndPts[p].A.b = Quantize(aUnqEndPts[p].A.b, Prec.b, pEP->bSigned);
aQntEndPts[p].B.r = Quantize(aUnqEndPts[p].B.r, Prec.r, pEP->bSigned);
aQntEndPts[p].B.g = Quantize(aUnqEndPts[p].B.g, Prec.g, pEP->bSigned);
aQntEndPts[p].B.b = Quantize(aUnqEndPts[p].B.b, Prec.b, pEP->bSigned);
}
}
_Use_decl_annotations_
void D3DX_BC6H::EmitBlock(const EncodeParams* pEP, const INTEndPntPair aEndPts[], const size_t aIndices[]) noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const uint8_t uRealMode = ms_aInfo[pEP->uMode].uMode;
const uint8_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
const uint8_t uIndexPrec = ms_aInfo[pEP->uMode].uIndexPrec;
const size_t uHeaderBits = uPartitions > 0 ? 82u : 65u;
const ModeDescriptor* desc = ms_aDesc[pEP->uMode];
size_t uStartBit = 0;
while (uStartBit < uHeaderBits)
{
switch (desc[uStartBit].m_eField)
{
case M: SetBit(uStartBit, uint8_t(uRealMode >> desc[uStartBit].m_uBit) & 0x01u); break;
case D: SetBit(uStartBit, uint8_t(pEP->uShape >> desc[uStartBit].m_uBit) & 0x01u); break;
case RW: SetBit(uStartBit, uint8_t(aEndPts[0].A.r >> desc[uStartBit].m_uBit) & 0x01u); break;
case RX: SetBit(uStartBit, uint8_t(aEndPts[0].B.r >> desc[uStartBit].m_uBit) & 0x01u); break;
case RY: SetBit(uStartBit, uint8_t(aEndPts[1].A.r >> desc[uStartBit].m_uBit) & 0x01u); break;
case RZ: SetBit(uStartBit, uint8_t(aEndPts[1].B.r >> desc[uStartBit].m_uBit) & 0x01u); break;
case GW: SetBit(uStartBit, uint8_t(aEndPts[0].A.g >> desc[uStartBit].m_uBit) & 0x01u); break;
case GX: SetBit(uStartBit, uint8_t(aEndPts[0].B.g >> desc[uStartBit].m_uBit) & 0x01u); break;
case GY: SetBit(uStartBit, uint8_t(aEndPts[1].A.g >> desc[uStartBit].m_uBit) & 0x01u); break;
case GZ: SetBit(uStartBit, uint8_t(aEndPts[1].B.g >> desc[uStartBit].m_uBit) & 0x01u); break;
case BW: SetBit(uStartBit, uint8_t(aEndPts[0].A.b >> desc[uStartBit].m_uBit) & 0x01u); break;
case BX: SetBit(uStartBit, uint8_t(aEndPts[0].B.b >> desc[uStartBit].m_uBit) & 0x01u); break;
case BY: SetBit(uStartBit, uint8_t(aEndPts[1].A.b >> desc[uStartBit].m_uBit) & 0x01u); break;
case BZ: SetBit(uStartBit, uint8_t(aEndPts[1].B.b >> desc[uStartBit].m_uBit) & 0x01u); break;
default: assert(false);
}
}
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
{
if (IsFixUpOffset(ms_aInfo[pEP->uMode].uPartitions, pEP->uShape, i))
SetBits(uStartBit, uIndexPrec - 1u, static_cast<uint8_t>(aIndices[i]));
else
SetBits(uStartBit, uIndexPrec, static_cast<uint8_t>(aIndices[i]));
}
assert(uStartBit == 128);
}
_Use_decl_annotations_
void D3DX_BC6H::Refine(EncodeParams* pEP) noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const uint8_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
assert(uPartitions < BC6H_MAX_REGIONS);
_Analysis_assume_(uPartitions < BC6H_MAX_REGIONS);
const bool bTransformed = ms_aInfo[pEP->uMode].bTransformed;
float aOrgErr[BC6H_MAX_REGIONS], aOptErr[BC6H_MAX_REGIONS];
INTEndPntPair aOrgEndPts[BC6H_MAX_REGIONS], aOptEndPts[BC6H_MAX_REGIONS];
size_t aOrgIdx[NUM_PIXELS_PER_BLOCK], aOptIdx[NUM_PIXELS_PER_BLOCK];
QuantizeEndPts(pEP, aOrgEndPts);
AssignIndices(pEP, aOrgEndPts, aOrgIdx, aOrgErr);
SwapIndices(pEP, aOrgEndPts, aOrgIdx);
if (bTransformed) TransformForward(aOrgEndPts);
if (EndPointsFit(pEP, aOrgEndPts))
{
if (bTransformed) TransformInverse(aOrgEndPts, ms_aInfo[pEP->uMode].RGBAPrec[0][0], pEP->bSigned);
OptimizeEndPoints(pEP, aOrgErr, aOrgEndPts, aOptEndPts);
AssignIndices(pEP, aOptEndPts, aOptIdx, aOptErr);
SwapIndices(pEP, aOptEndPts, aOptIdx);
float fOrgTotErr = 0.0f, fOptTotErr = 0.0f;
for (size_t p = 0; p <= uPartitions; ++p)
{
fOrgTotErr += aOrgErr[p];
fOptTotErr += aOptErr[p];
}
if (bTransformed) TransformForward(aOptEndPts);
if (EndPointsFit(pEP, aOptEndPts) && fOptTotErr < fOrgTotErr && fOptTotErr < pEP->fBestErr)
{
pEP->fBestErr = fOptTotErr;
EmitBlock(pEP, aOptEndPts, aOptIdx);
}
else if (fOrgTotErr < pEP->fBestErr)
{
// either it stopped fitting when we optimized it, or there was no improvement
// so go back to the unoptimized endpoints which we know will fit
if (bTransformed) TransformForward(aOrgEndPts);
pEP->fBestErr = fOrgTotErr;
EmitBlock(pEP, aOrgEndPts, aOrgIdx);
}
}
}
_Use_decl_annotations_
void D3DX_BC6H::GeneratePaletteUnquantized(const EncodeParams* pEP, size_t uRegion, INTColor aPalette[]) noexcept
{
assert(pEP);
assert(uRegion < BC6H_MAX_REGIONS && pEP->uShape < BC6H_MAX_SHAPES);
_Analysis_assume_(uRegion < BC6H_MAX_REGIONS && pEP->uShape < BC6H_MAX_SHAPES);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const INTEndPntPair& endPts = pEP->aUnqEndPts[pEP->uShape][uRegion];
const uint8_t uIndexPrec = ms_aInfo[pEP->uMode].uIndexPrec;
auto const uNumIndices = static_cast<const uint8_t>(1u << uIndexPrec);
assert(uNumIndices > 0);
_Analysis_assume_(uNumIndices > 0);
const int* aWeights = nullptr;
switch (uIndexPrec)
{
case 3: aWeights = g_aWeights3; assert(uNumIndices <= 8); _Analysis_assume_(uNumIndices <= 8); break;
case 4: aWeights = g_aWeights4; assert(uNumIndices <= 16); _Analysis_assume_(uNumIndices <= 16); break;
default:
assert(false);
for (size_t i = 0; i < uNumIndices; ++i)
{
#pragma prefast(suppress:22102 22103, "writing blocks in two halves confuses tool")
aPalette[i] = INTColor(0, 0, 0);
}
return;
}
for (size_t i = 0; i < uNumIndices; ++i)
{
aPalette[i].r = (endPts.A.r * (BC67_WEIGHT_MAX - aWeights[i]) + endPts.B.r * aWeights[i] + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT;
aPalette[i].g = (endPts.A.g * (BC67_WEIGHT_MAX - aWeights[i]) + endPts.B.g * aWeights[i] + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT;
aPalette[i].b = (endPts.A.b * (BC67_WEIGHT_MAX - aWeights[i]) + endPts.B.b * aWeights[i] + BC67_WEIGHT_ROUND) >> BC67_WEIGHT_SHIFT;
}
}
_Use_decl_annotations_
float D3DX_BC6H::MapColors(const EncodeParams* pEP, size_t uRegion, size_t np, const size_t* auIndex) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const uint8_t uIndexPrec = ms_aInfo[pEP->uMode].uIndexPrec;
auto const uNumIndices = static_cast<const uint8_t>(1u << uIndexPrec);
INTColor aPalette[BC6H_MAX_INDICES];
GeneratePaletteUnquantized(pEP, uRegion, aPalette);
float fTotalErr = 0.0f;
for (size_t i = 0; i < np; ++i)
{
float fBestErr = Norm(pEP->aIPixels[auIndex[i]], aPalette[0]);
for (uint8_t j = 1; j < uNumIndices && fBestErr > 0.0f; ++j)
{
const float fErr = Norm(pEP->aIPixels[auIndex[i]], aPalette[j]);
if (fErr > fBestErr) break; // error increased, so we're done searching
if (fErr < fBestErr) fBestErr = fErr;
}
fTotalErr += fBestErr;
}
return fTotalErr;
}
_Use_decl_annotations_
float D3DX_BC6H::RoughMSE(EncodeParams* pEP) const noexcept
{
assert(pEP);
assert(pEP->uShape < BC6H_MAX_SHAPES);
_Analysis_assume_(pEP->uShape < BC6H_MAX_SHAPES);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
INTEndPntPair* aEndPts = pEP->aUnqEndPts[pEP->uShape];
const uint8_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
assert(uPartitions < BC6H_MAX_REGIONS);
_Analysis_assume_(uPartitions < BC6H_MAX_REGIONS);
size_t auPixIdx[NUM_PIXELS_PER_BLOCK];
float fError = 0.0f;
for (size_t p = 0; p <= uPartitions; ++p)
{
size_t np = 0;
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
{
if (g_aPartitionTable[uPartitions][pEP->uShape][i] == p)
{
auPixIdx[np++] = i;
}
}
// handle simple cases
assert(np > 0);
if (np == 1)
{
aEndPts[p].A = pEP->aIPixels[auPixIdx[0]];
aEndPts[p].B = pEP->aIPixels[auPixIdx[0]];
continue;
}
else if (np == 2)
{
aEndPts[p].A = pEP->aIPixels[auPixIdx[0]];
aEndPts[p].B = pEP->aIPixels[auPixIdx[1]];
continue;
}
HDRColorA epA, epB;
OptimizeRGB(pEP->aHDRPixels, &epA, &epB, 4, np, auPixIdx);
aEndPts[p].A.Set(epA, pEP->bSigned);
aEndPts[p].B.Set(epB, pEP->bSigned);
if (pEP->bSigned)
{
aEndPts[p].A.Clamp(-F16MAX, F16MAX);
aEndPts[p].B.Clamp(-F16MAX, F16MAX);
}
else
{
aEndPts[p].A.Clamp(0, F16MAX);
aEndPts[p].B.Clamp(0, F16MAX);
}
fError += MapColors(pEP, p, np, auPixIdx);
}
return fError;
}
//-------------------------------------------------------------------------------------
// BC7 Compression
//-------------------------------------------------------------------------------------
_Use_decl_annotations_
void D3DX_BC7::Decode(HDRColorA* pOut) const noexcept
{
assert(pOut);
size_t uFirst = 0;
while (uFirst < 128 && !GetBit(uFirst)) {}
const uint8_t uMode = uint8_t(uFirst - 1);
if (uMode < 8)
{
const uint8_t uPartitions = ms_aInfo[uMode].uPartitions;
assert(uPartitions < BC7_MAX_REGIONS);
_Analysis_assume_(uPartitions < BC7_MAX_REGIONS);
auto const uNumEndPts = static_cast<const uint8_t>((unsigned(uPartitions) + 1u) << 1);
const uint8_t uIndexPrec = ms_aInfo[uMode].uIndexPrec;
const uint8_t uIndexPrec2 = ms_aInfo[uMode].uIndexPrec2;
size_t i;
size_t uStartBit = size_t(uMode) + 1;
uint8_t P[6];
const uint8_t uShape = GetBits(uStartBit, ms_aInfo[uMode].uPartitionBits);
assert(uShape < BC7_MAX_SHAPES);
_Analysis_assume_(uShape < BC7_MAX_SHAPES);
const uint8_t uRotation = GetBits(uStartBit, ms_aInfo[uMode].uRotationBits);
assert(uRotation < 4);
const uint8_t uIndexMode = GetBits(uStartBit, ms_aInfo[uMode].uIndexModeBits);
assert(uIndexMode < 2);
LDRColorA c[BC7_MAX_REGIONS << 1];
const LDRColorA RGBAPrec = ms_aInfo[uMode].RGBAPrec;
const LDRColorA RGBAPrecWithP = ms_aInfo[uMode].RGBAPrecWithP;
assert(uNumEndPts <= (BC7_MAX_REGIONS << 1));
// Red channel
for (i = 0; i < uNumEndPts; i++)
{
if (uStartBit + RGBAPrec.r > 128)
{
#if defined(_WIN32) && defined(_DEBUG)
OutputDebugStringA("BC7: Invalid block encountered during decoding\n");
#endif
FillWithErrorColors(pOut);
return;
}
c[i].r = GetBits(uStartBit, RGBAPrec.r);
}
// Green channel
for (i = 0; i < uNumEndPts; i++)
{
if (uStartBit + RGBAPrec.g > 128)
{
#if defined(_WIN32) && defined(_DEBUG)
OutputDebugStringA("BC7: Invalid block encountered during decoding\n");
#endif
FillWithErrorColors(pOut);
return;
}
c[i].g = GetBits(uStartBit, RGBAPrec.g);
}
// Blue channel
for (i = 0; i < uNumEndPts; i++)
{
if (uStartBit + RGBAPrec.b > 128)
{
#if defined(_WIN32) && defined(_DEBUG)
OutputDebugStringA("BC7: Invalid block encountered during decoding\n");
#endif
FillWithErrorColors(pOut);
return;
}
c[i].b = GetBits(uStartBit, RGBAPrec.b);
}
// Alpha channel
for (i = 0; i < uNumEndPts; i++)
{
if (uStartBit + RGBAPrec.a > 128)
{
#if defined(_WIN32) && defined(_DEBUG)
OutputDebugStringA("BC7: Invalid block encountered during decoding\n");
#endif
FillWithErrorColors(pOut);
return;
}
c[i].a = RGBAPrec.a ? GetBits(uStartBit, RGBAPrec.a) : 255u;
}
// P-bits
assert(ms_aInfo[uMode].uPBits <= 6);
_Analysis_assume_(ms_aInfo[uMode].uPBits <= 6);
for (i = 0; i < ms_aInfo[uMode].uPBits; i++)
{
if (uStartBit > 127)
{
#if defined(_WIN32) && defined(_DEBUG)
OutputDebugStringA("BC7: Invalid block encountered during decoding\n");
#endif
FillWithErrorColors(pOut);
return;
}
P[i] = GetBit(uStartBit);
}
if (ms_aInfo[uMode].uPBits)
{
for (i = 0; i < uNumEndPts; i++)
{
size_t pi = i * ms_aInfo[uMode].uPBits / uNumEndPts;
for (uint8_t ch = 0; ch < BC7_NUM_CHANNELS; ch++)
{
if (RGBAPrec[ch] != RGBAPrecWithP[ch])
{
c[i][ch] = static_cast<uint8_t>((unsigned(c[i][ch]) << 1) | P[pi]);
}
}
}
}
for (i = 0; i < uNumEndPts; i++)
{
#ifdef __GNUC__
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wstringop-overflow"
#endif
c[i] = Unquantize(c[i], RGBAPrecWithP);
#ifdef __GNUC_
#pragma GCC diagnostic pop
#endif
}
uint8_t w1[NUM_PIXELS_PER_BLOCK], w2[NUM_PIXELS_PER_BLOCK];
// read color indices
for (i = 0; i < NUM_PIXELS_PER_BLOCK; i++)
{
const size_t uNumBits = IsFixUpOffset(ms_aInfo[uMode].uPartitions, uShape, i) ? uIndexPrec - 1u : uIndexPrec;
if (uStartBit + uNumBits > 128)
{
#if defined(_WIN32) && defined(_DEBUG)
OutputDebugStringA("BC7: Invalid block encountered during decoding\n");
#endif
FillWithErrorColors(pOut);
return;
}
w1[i] = GetBits(uStartBit, uNumBits);
}
// read alpha indices
if (uIndexPrec2)
{
for (i = 0; i < NUM_PIXELS_PER_BLOCK; i++)
{
const size_t uNumBits = i ? uIndexPrec2 : uIndexPrec2 - 1u;
if (uStartBit + uNumBits > 128)
{
#if defined(_WIN32) && defined(_DEBUG)
OutputDebugStringA("BC7: Invalid block encountered during decoding\n");
#endif
FillWithErrorColors(pOut);
return;
}
w2[i] = GetBits(uStartBit, uNumBits);
}
}
for (i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
{
const uint8_t uRegion = g_aPartitionTable[uPartitions][uShape][i];
LDRColorA outPixel;
if (uIndexPrec2 == 0)
{
LDRColorA::Interpolate(c[uRegion << 1], c[(uRegion << 1) + 1], w1[i], w1[i], uIndexPrec, uIndexPrec, outPixel);
}
else
{
if (uIndexMode == 0)
{
LDRColorA::Interpolate(c[uRegion << 1], c[(uRegion << 1) + 1], w1[i], w2[i], uIndexPrec, uIndexPrec2, outPixel);
}
else
{
LDRColorA::Interpolate(c[uRegion << 1], c[(uRegion << 1) + 1], w2[i], w1[i], uIndexPrec2, uIndexPrec, outPixel);
}
}
switch (uRotation)
{
case 1: std::swap(outPixel.r, outPixel.a); break;
case 2: std::swap(outPixel.g, outPixel.a); break;
case 3: std::swap(outPixel.b, outPixel.a); break;
default: break;
}
pOut[i] = HDRColorA(outPixel);
}
}
else
{
#if defined(_WIN32) && defined(_DEBUG)
OutputDebugStringA("BC7: Reserved mode 8 encountered during decoding\n");
#endif
// Per the BC7 format spec, we must return transparent black
memset(pOut, 0, sizeof(HDRColorA) * NUM_PIXELS_PER_BLOCK);
}
}
_Use_decl_annotations_
void D3DX_BC7::Encode(uint32_t flags, const HDRColorA* const pIn) noexcept
{
assert(pIn);
D3DX_BC7 final = *this;
EncodeParams EP(pIn);
float fMSEBest = FLT_MAX;
uint32_t alphaMask = 0xFF;
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
{
EP.aLDRPixels[i].r = uint8_t(std::max<float>(0.0f, std::min<float>(255.0f, pIn[i].r * 255.0f + 0.01f)));
EP.aLDRPixels[i].g = uint8_t(std::max<float>(0.0f, std::min<float>(255.0f, pIn[i].g * 255.0f + 0.01f)));
EP.aLDRPixels[i].b = uint8_t(std::max<float>(0.0f, std::min<float>(255.0f, pIn[i].b * 255.0f + 0.01f)));
EP.aLDRPixels[i].a = uint8_t(std::max<float>(0.0f, std::min<float>(255.0f, pIn[i].a * 255.0f + 0.01f)));
alphaMask &= EP.aLDRPixels[i].a;
}
const bool bHasAlpha = (alphaMask != 0xFF);
for (EP.uMode = 0; EP.uMode < 8 && fMSEBest > 0; ++EP.uMode)
{
if (!(flags & BC_FLAGS_USE_3SUBSETS) && (EP.uMode == 0 || EP.uMode == 2))
{
// 3 subset modes tend to be used rarely and add significant compression time
continue;
}
if ((flags & TEX_COMPRESS_BC7_QUICK) && (EP.uMode != 6))
{
// Use only mode 6
continue;
}
if ((!bHasAlpha) && (EP.uMode == 7))
{
// There is no value in using mode 7 for completely opaque blocks (the other 2 subset modes handle this case for opaque blocks), so skip it for a small perf win.
continue;
}
const size_t uShapes = size_t(1) << ms_aInfo[EP.uMode].uPartitionBits;
assert(uShapes <= BC7_MAX_SHAPES);
_Analysis_assume_(uShapes <= BC7_MAX_SHAPES);
const size_t uNumRots = size_t(1) << ms_aInfo[EP.uMode].uRotationBits;
const size_t uNumIdxMode = size_t(1) << ms_aInfo[EP.uMode].uIndexModeBits;
// Number of rough cases to look at. reasonable values of this are 1, uShapes/4, and uShapes
// uShapes/4 gets nearly all the cases; you can increase that a bit (say by 3 or 4) if you really want to squeeze the last bit out
const size_t uItems = std::max<size_t>(1, uShapes >> 2);
float afRoughMSE[BC7_MAX_SHAPES];
size_t auShape[BC7_MAX_SHAPES];
for (size_t r = 0; r < uNumRots && fMSEBest > 0; ++r)
{
switch (r)
{
case 1: for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++) std::swap(EP.aLDRPixels[i].r, EP.aLDRPixels[i].a); break;
case 2: for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++) std::swap(EP.aLDRPixels[i].g, EP.aLDRPixels[i].a); break;
case 3: for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++) std::swap(EP.aLDRPixels[i].b, EP.aLDRPixels[i].a); break;
default: break;
}
for (size_t im = 0; im < uNumIdxMode && fMSEBest > 0; ++im)
{
// pick the best uItems shapes and refine these.
for (size_t s = 0; s < uShapes; s++)
{
afRoughMSE[s] = RoughMSE(&EP, s, im);
auShape[s] = s;
}
// Bubble up the first uItems items
for (size_t i = 0; i < uItems; i++)
{
for (size_t j = i + 1; j < uShapes; j++)
{
if (afRoughMSE[i] > afRoughMSE[j])
{
std::swap(afRoughMSE[i], afRoughMSE[j]);
std::swap(auShape[i], auShape[j]);
}
}
}
for (size_t i = 0; i < uItems && fMSEBest > 0; i++)
{
const float fMSE = Refine(&EP, auShape[i], r, im);
if (fMSE < fMSEBest)
{
final = *this;
fMSEBest = fMSE;
}
}
}
switch (r)
{
case 1: for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++) std::swap(EP.aLDRPixels[i].r, EP.aLDRPixels[i].a); break;
case 2: for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++) std::swap(EP.aLDRPixels[i].g, EP.aLDRPixels[i].a); break;
case 3: for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++) std::swap(EP.aLDRPixels[i].b, EP.aLDRPixels[i].a); break;
default: break;
}
}
}
*this = final;
}
//-------------------------------------------------------------------------------------
_Use_decl_annotations_
void D3DX_BC7::GeneratePaletteQuantized(const EncodeParams* pEP, size_t uIndexMode, const LDREndPntPair& endPts, LDRColorA aPalette[]) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const size_t uIndexPrec = uIndexMode ? ms_aInfo[pEP->uMode].uIndexPrec2 : ms_aInfo[pEP->uMode].uIndexPrec;
const size_t uIndexPrec2 = uIndexMode ? ms_aInfo[pEP->uMode].uIndexPrec : ms_aInfo[pEP->uMode].uIndexPrec2;
const size_t uNumIndices = size_t(1) << uIndexPrec;
const size_t uNumIndices2 = size_t(1) << uIndexPrec2;
assert(uNumIndices > 0 && uNumIndices2 > 0);
_Analysis_assume_(uNumIndices > 0 && uNumIndices2 > 0);
assert((uNumIndices <= BC7_MAX_INDICES) && (uNumIndices2 <= BC7_MAX_INDICES));
_Analysis_assume_((uNumIndices <= BC7_MAX_INDICES) && (uNumIndices2 <= BC7_MAX_INDICES));
const LDRColorA a = Unquantize(endPts.A, ms_aInfo[pEP->uMode].RGBAPrecWithP);
const LDRColorA b = Unquantize(endPts.B, ms_aInfo[pEP->uMode].RGBAPrecWithP);
if (uIndexPrec2 == 0)
{
for (size_t i = 0; i < uNumIndices; i++)
LDRColorA::Interpolate(a, b, i, i, uIndexPrec, uIndexPrec, aPalette[i]);
}
else
{
for (size_t i = 0; i < uNumIndices; i++)
LDRColorA::InterpolateRGB(a, b, i, uIndexPrec, aPalette[i]);
for (size_t i = 0; i < uNumIndices2; i++)
LDRColorA::InterpolateA(a, b, i, uIndexPrec2, aPalette[i]);
}
}
_Use_decl_annotations_
float D3DX_BC7::PerturbOne(const EncodeParams* pEP, const LDRColorA aColors[], size_t np, size_t uIndexMode, size_t ch,
const LDREndPntPair &oldEndPts, LDREndPntPair &newEndPts, float fOldErr, uint8_t do_b) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const int prec = ms_aInfo[pEP->uMode].RGBAPrecWithP[ch];
LDREndPntPair tmp_endPts = newEndPts = oldEndPts;
float fMinErr = fOldErr;
uint8_t* pnew_c = (do_b ? &newEndPts.B[ch] : &newEndPts.A[ch]);
uint8_t* ptmp_c = (do_b ? &tmp_endPts.B[ch] : &tmp_endPts.A[ch]);
// do a logarithmic search for the best error for this endpoint (which)
for (int step = 1 << (prec - 1); step; step >>= 1)
{
bool bImproved = false;
int beststep = 0;
for (int sign = -1; sign <= 1; sign += 2)
{
int tmp = int(*pnew_c) + sign * step;
if (tmp < 0 || tmp >= (1 << prec))
continue;
else
*ptmp_c = static_cast<uint8_t>(tmp);
const float fTotalErr = MapColors(pEP, aColors, np, uIndexMode, tmp_endPts, fMinErr);
if (fTotalErr < fMinErr)
{
bImproved = true;
fMinErr = fTotalErr;
beststep = sign * step;
}
}
// if this was an improvement, move the endpoint and continue search from there
if (bImproved)
*pnew_c = uint8_t(int(*pnew_c) + beststep);
}
return fMinErr;
}
// perturb the endpoints at least -3 to 3.
// always ensure endpoint ordering is preserved (no need to overlap the scan)
_Use_decl_annotations_
void D3DX_BC7::Exhaustive(const EncodeParams* pEP, const LDRColorA aColors[], size_t np, size_t uIndexMode, size_t ch,
float& fOrgErr, LDREndPntPair& optEndPt) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const uint8_t uPrec = ms_aInfo[pEP->uMode].RGBAPrecWithP[ch];
LDREndPntPair tmpEndPt;
if (fOrgErr == 0)
return;
constexpr int delta = 5;
// ok figure out the range of A and B
tmpEndPt = optEndPt;
const int alow = std::max<int>(0, int(optEndPt.A[ch]) - delta);
const int ahigh = std::min<int>((1 << uPrec) - 1, int(optEndPt.A[ch]) + delta);
const int blow = std::max<int>(0, int(optEndPt.B[ch]) - delta);
const int bhigh = std::min<int>((1 << uPrec) - 1, int(optEndPt.B[ch]) + delta);
int amin = 0;
int bmin = 0;
float fBestErr = fOrgErr;
if (optEndPt.A[ch] <= optEndPt.B[ch])
{
// keep a <= b
for (int a = alow; a <= ahigh; ++a)
{
for (int b = std::max<int>(a, blow); b < bhigh; ++b)
{
tmpEndPt.A[ch] = static_cast<uint8_t>(a);
tmpEndPt.B[ch] = static_cast<uint8_t>(b);
const float fErr = MapColors(pEP, aColors, np, uIndexMode, tmpEndPt, fBestErr);
if (fErr < fBestErr)
{
amin = a;
bmin = b;
fBestErr = fErr;
}
}
}
}
else
{
// keep b <= a
for (int b = blow; b < bhigh; ++b)
{
for (int a = std::max<int>(b, alow); a <= ahigh; ++a)
{
tmpEndPt.A[ch] = static_cast<uint8_t>(a);
tmpEndPt.B[ch] = static_cast<uint8_t>(b);
const float fErr = MapColors(pEP, aColors, np, uIndexMode, tmpEndPt, fBestErr);
if (fErr < fBestErr)
{
amin = a;
bmin = b;
fBestErr = fErr;
}
}
}
}
if (fBestErr < fOrgErr)
{
optEndPt.A[ch] = static_cast<uint8_t>(amin);
optEndPt.B[ch] = static_cast<uint8_t>(bmin);
fOrgErr = fBestErr;
}
}
_Use_decl_annotations_
void D3DX_BC7::OptimizeOne(const EncodeParams* pEP, const LDRColorA aColors[], size_t np, size_t uIndexMode,
float fOrgErr, const LDREndPntPair& org, LDREndPntPair& opt) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
float fOptErr = fOrgErr;
opt = org;
LDREndPntPair new_a, new_b;
LDREndPntPair newEndPts;
uint8_t do_b;
// now optimize each channel separately
for (size_t ch = 0; ch < BC7_NUM_CHANNELS; ++ch)
{
if (ms_aInfo[pEP->uMode].RGBAPrecWithP[ch] == 0)
continue;
// figure out which endpoint when perturbed gives the most improvement and start there
// if we just alternate, we can easily end up in a local minima
const float fErr0 = PerturbOne(pEP, aColors, np, uIndexMode, ch, opt, new_a, fOptErr, 0); // perturb endpt A
const float fErr1 = PerturbOne(pEP, aColors, np, uIndexMode, ch, opt, new_b, fOptErr, 1); // perturb endpt B
uint8_t& copt_a = opt.A[ch];
uint8_t& copt_b = opt.B[ch];
uint8_t& cnew_a = new_a.A[ch];
uint8_t& cnew_b = new_a.B[ch];
if (fErr0 < fErr1)
{
if (fErr0 >= fOptErr)
continue;
copt_a = cnew_a;
fOptErr = fErr0;
do_b = 1; // do B next
}
else
{
if (fErr1 >= fOptErr)
continue;
copt_b = cnew_b;
fOptErr = fErr1;
do_b = 0; // do A next
}
// now alternate endpoints and keep trying until there is no improvement
for (; ; )
{
const float fErr = PerturbOne(pEP, aColors, np, uIndexMode, ch, opt, newEndPts, fOptErr, do_b);
if (fErr >= fOptErr)
break;
if (do_b == 0)
copt_a = cnew_a;
else
copt_b = cnew_b;
fOptErr = fErr;
do_b = 1u - do_b; // now move the other endpoint
}
}
// finally, do a small exhaustive search around what we think is the global minima to be sure
for (size_t ch = 0; ch < BC7_NUM_CHANNELS; ch++)
Exhaustive(pEP, aColors, np, uIndexMode, ch, fOptErr, opt);
}
_Use_decl_annotations_
void D3DX_BC7::OptimizeEndPoints(const EncodeParams* pEP, size_t uShape, size_t uIndexMode, const float afOrgErr[],
const LDREndPntPair aOrgEndPts[], LDREndPntPair aOptEndPts[]) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const uint8_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
assert(uPartitions < BC7_MAX_REGIONS && uShape < BC7_MAX_SHAPES);
_Analysis_assume_(uPartitions < BC7_MAX_REGIONS && uShape < BC7_MAX_SHAPES);
LDRColorA aPixels[NUM_PIXELS_PER_BLOCK];
for (size_t p = 0; p <= uPartitions; ++p)
{
// collect the pixels in the region
size_t np = 0;
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
if (g_aPartitionTable[uPartitions][uShape][i] == p)
aPixels[np++] = pEP->aLDRPixels[i];
OptimizeOne(pEP, aPixels, np, uIndexMode, afOrgErr[p], aOrgEndPts[p], aOptEndPts[p]);
}
}
_Use_decl_annotations_
void D3DX_BC7::AssignIndices(const EncodeParams* pEP, size_t uShape, size_t uIndexMode, LDREndPntPair endPts[], size_t aIndices[], size_t aIndices2[],
float afTotErr[]) const noexcept
{
assert(pEP);
assert(uShape < BC7_MAX_SHAPES);
_Analysis_assume_(uShape < BC7_MAX_SHAPES);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const uint8_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
assert(uPartitions < BC7_MAX_REGIONS);
_Analysis_assume_(uPartitions < BC7_MAX_REGIONS);
const uint8_t uIndexPrec = uIndexMode ? ms_aInfo[pEP->uMode].uIndexPrec2 : ms_aInfo[pEP->uMode].uIndexPrec;
const uint8_t uIndexPrec2 = uIndexMode ? ms_aInfo[pEP->uMode].uIndexPrec : ms_aInfo[pEP->uMode].uIndexPrec2;
auto const uNumIndices = static_cast<const uint8_t>(1u << uIndexPrec);
auto const uNumIndices2 = static_cast<const uint8_t>(1u << uIndexPrec2);
assert((uNumIndices <= BC7_MAX_INDICES) && (uNumIndices2 <= BC7_MAX_INDICES));
_Analysis_assume_((uNumIndices <= BC7_MAX_INDICES) && (uNumIndices2 <= BC7_MAX_INDICES));
const uint8_t uHighestIndexBit = uint8_t(uNumIndices >> 1);
const uint8_t uHighestIndexBit2 = uint8_t(uNumIndices2 >> 1);
LDRColorA aPalette[BC7_MAX_REGIONS][BC7_MAX_INDICES];
// build list of possibles
for (size_t p = 0; p <= uPartitions; p++)
{
GeneratePaletteQuantized(pEP, uIndexMode, endPts[p], aPalette[p]);
afTotErr[p] = 0;
}
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++)
{
uint8_t uRegion = g_aPartitionTable[uPartitions][uShape][i];
assert(uRegion < BC7_MAX_REGIONS);
_Analysis_assume_(uRegion < BC7_MAX_REGIONS);
afTotErr[uRegion] += ComputeError(pEP->aLDRPixels[i], aPalette[uRegion], uIndexPrec, uIndexPrec2, &(aIndices[i]), &(aIndices2[i]));
}
// swap endpoints as needed to ensure that the indices at index_positions have a 0 high-order bit
if (uIndexPrec2 == 0)
{
for (size_t p = 0; p <= uPartitions; p++)
{
if (aIndices[g_aFixUp[uPartitions][uShape][p]] & uHighestIndexBit)
{
std::swap(endPts[p].A, endPts[p].B);
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++)
if (g_aPartitionTable[uPartitions][uShape][i] == p)
aIndices[i] = uNumIndices - 1 - aIndices[i];
}
assert((aIndices[g_aFixUp[uPartitions][uShape][p]] & uHighestIndexBit) == 0);
}
}
else
{
for (size_t p = 0; p <= uPartitions; p++)
{
if (aIndices[g_aFixUp[uPartitions][uShape][p]] & uHighestIndexBit)
{
std::swap(endPts[p].A.r, endPts[p].B.r);
std::swap(endPts[p].A.g, endPts[p].B.g);
std::swap(endPts[p].A.b, endPts[p].B.b);
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++)
if (g_aPartitionTable[uPartitions][uShape][i] == p)
aIndices[i] = uNumIndices - 1 - aIndices[i];
}
assert((aIndices[g_aFixUp[uPartitions][uShape][p]] & uHighestIndexBit) == 0);
if (aIndices2[0] & uHighestIndexBit2)
{
std::swap(endPts[p].A.a, endPts[p].B.a);
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++)
aIndices2[i] = uNumIndices2 - 1 - aIndices2[i];
}
assert((aIndices2[0] & uHighestIndexBit2) == 0);
}
}
}
_Use_decl_annotations_
void D3DX_BC7::EmitBlock(const EncodeParams* pEP, size_t uShape, size_t uRotation, size_t uIndexMode, const LDREndPntPair aEndPts[], const size_t aIndex[], const size_t aIndex2[]) noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const uint8_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
assert(uPartitions < BC7_MAX_REGIONS);
_Analysis_assume_(uPartitions < BC7_MAX_REGIONS);
const size_t uPBits = ms_aInfo[pEP->uMode].uPBits;
const size_t uIndexPrec = ms_aInfo[pEP->uMode].uIndexPrec;
const size_t uIndexPrec2 = ms_aInfo[pEP->uMode].uIndexPrec2;
const LDRColorA RGBAPrec = ms_aInfo[pEP->uMode].RGBAPrec;
const LDRColorA RGBAPrecWithP = ms_aInfo[pEP->uMode].RGBAPrecWithP;
size_t i;
size_t uStartBit = 0;
SetBits(uStartBit, pEP->uMode, 0);
SetBits(uStartBit, 1, 1);
SetBits(uStartBit, ms_aInfo[pEP->uMode].uRotationBits, static_cast<uint8_t>(uRotation));
SetBits(uStartBit, ms_aInfo[pEP->uMode].uIndexModeBits, static_cast<uint8_t>(uIndexMode));
SetBits(uStartBit, ms_aInfo[pEP->uMode].uPartitionBits, static_cast<uint8_t>(uShape));
if (uPBits)
{
const size_t uNumEP = (size_t(uPartitions) + 1) << 1;
uint8_t aPVote[BC7_MAX_REGIONS << 1] = { 0,0,0,0,0,0 };
uint8_t aCount[BC7_MAX_REGIONS << 1] = { 0,0,0,0,0,0 };
for (uint8_t ch = 0; ch < BC7_NUM_CHANNELS; ch++)
{
uint8_t ep = 0;
for (i = 0; i <= uPartitions; i++)
{
if (RGBAPrec[ch] == RGBAPrecWithP[ch])
{
SetBits(uStartBit, RGBAPrec[ch], aEndPts[i].A[ch]);
SetBits(uStartBit, RGBAPrec[ch], aEndPts[i].B[ch]);
}
else
{
SetBits(uStartBit, RGBAPrec[ch], uint8_t(aEndPts[i].A[ch] >> 1));
SetBits(uStartBit, RGBAPrec[ch], uint8_t(aEndPts[i].B[ch] >> 1));
size_t idx = ep++ * uPBits / uNumEP;
assert(idx < (BC7_MAX_REGIONS << 1));
_Analysis_assume_(idx < (BC7_MAX_REGIONS << 1));
aPVote[idx] += aEndPts[i].A[ch] & 0x01;
aCount[idx]++;
idx = ep++ * uPBits / uNumEP;
assert(idx < (BC7_MAX_REGIONS << 1));
_Analysis_assume_(idx < (BC7_MAX_REGIONS << 1));
aPVote[idx] += aEndPts[i].B[ch] & 0x01;
aCount[idx]++;
}
}
}
for (i = 0; i < uPBits; i++)
{
SetBits(uStartBit, 1, (aPVote[i] >(aCount[i] >> 1)) ? 1u : 0u);
}
}
else
{
for (size_t ch = 0; ch < BC7_NUM_CHANNELS; ch++)
{
for (i = 0; i <= uPartitions; i++)
{
SetBits(uStartBit, RGBAPrec[ch], aEndPts[i].A[ch]);
SetBits(uStartBit, RGBAPrec[ch], aEndPts[i].B[ch]);
}
}
}
const size_t* aI1 = uIndexMode ? aIndex2 : aIndex;
const size_t* aI2 = uIndexMode ? aIndex : aIndex2;
for (i = 0; i < NUM_PIXELS_PER_BLOCK; i++)
{
if (IsFixUpOffset(ms_aInfo[pEP->uMode].uPartitions, uShape, i))
SetBits(uStartBit, uIndexPrec - 1, static_cast<uint8_t>(aI1[i]));
else
SetBits(uStartBit, uIndexPrec, static_cast<uint8_t>(aI1[i]));
}
if (uIndexPrec2)
for (i = 0; i < NUM_PIXELS_PER_BLOCK; i++)
SetBits(uStartBit, i ? uIndexPrec2 : uIndexPrec2 - 1, static_cast<uint8_t>(aI2[i]));
assert(uStartBit == 128);
}
_Use_decl_annotations_
void D3DX_BC7::FixEndpointPBits(const EncodeParams* pEP, const LDREndPntPair *pOrigEndpoints, LDREndPntPair *pFixedEndpoints) noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const size_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
assert(uPartitions < BC7_MAX_REGIONS);
_Analysis_assume_(uPartitions < BC7_MAX_REGIONS);
pFixedEndpoints[0] = pOrigEndpoints[0];
pFixedEndpoints[1] = pOrigEndpoints[1];
pFixedEndpoints[2] = pOrigEndpoints[2];
const size_t uPBits = ms_aInfo[pEP->uMode].uPBits;
if (uPBits)
{
const size_t uNumEP = size_t(1 + uPartitions) << 1;
uint8_t aPVote[BC7_MAX_REGIONS << 1] = { 0,0,0,0,0,0 };
uint8_t aCount[BC7_MAX_REGIONS << 1] = { 0,0,0,0,0,0 };
const LDRColorA RGBAPrec = ms_aInfo[pEP->uMode].RGBAPrec;
const LDRColorA RGBAPrecWithP = ms_aInfo[pEP->uMode].RGBAPrecWithP;
for (uint8_t ch = 0; ch < BC7_NUM_CHANNELS; ch++)
{
uint8_t ep = 0;
for (size_t i = 0; i <= uPartitions; i++)
{
if (RGBAPrec[ch] == RGBAPrecWithP[ch])
{
pFixedEndpoints[i].A[ch] = pOrigEndpoints[i].A[ch];
pFixedEndpoints[i].B[ch] = pOrigEndpoints[i].B[ch];
}
else
{
pFixedEndpoints[i].A[ch] = uint8_t(pOrigEndpoints[i].A[ch] >> 1);
pFixedEndpoints[i].B[ch] = uint8_t(pOrigEndpoints[i].B[ch] >> 1);
size_t idx = ep++ * uPBits / uNumEP;
assert(idx < (BC7_MAX_REGIONS << 1));
_Analysis_assume_(idx < (BC7_MAX_REGIONS << 1));
aPVote[idx] += pOrigEndpoints[i].A[ch] & 0x01;
aCount[idx]++;
idx = ep++ * uPBits / uNumEP;
assert(idx < (BC7_MAX_REGIONS << 1));
_Analysis_assume_(idx < (BC7_MAX_REGIONS << 1));
aPVote[idx] += pOrigEndpoints[i].B[ch] & 0x01;
aCount[idx]++;
}
}
}
// Compute the actual pbits we'll use when we encode block. Note this is not
// rounding the component indices correctly in cases the pbits != a component's LSB.
int pbits[BC7_MAX_REGIONS << 1];
for (size_t i = 0; i < uPBits; i++)
pbits[i] = aPVote[i] >(aCount[i] >> 1) ? 1 : 0;
// Now calculate the actual endpoints with proper pbits, so error calculations are accurate.
if (pEP->uMode == 1)
{
// shared pbits
for (uint8_t ch = 0; ch < BC7_NUM_CHANNELS; ch++)
{
for (size_t i = 0; i <= uPartitions; i++)
{
pFixedEndpoints[i].A[ch] = static_cast<uint8_t>((pFixedEndpoints[i].A[ch] << 1) | pbits[i]);
pFixedEndpoints[i].B[ch] = static_cast<uint8_t>((pFixedEndpoints[i].B[ch] << 1) | pbits[i]);
}
}
}
else
{
for (uint8_t ch = 0; ch < BC7_NUM_CHANNELS; ch++)
{
for (size_t i = 0; i <= uPartitions; i++)
{
pFixedEndpoints[i].A[ch] = static_cast<uint8_t>((pFixedEndpoints[i].A[ch] << 1) | pbits[i * 2 + 0]);
pFixedEndpoints[i].B[ch] = static_cast<uint8_t>((pFixedEndpoints[i].B[ch] << 1) | pbits[i * 2 + 1]);
}
}
}
}
}
_Use_decl_annotations_
float D3DX_BC7::Refine(const EncodeParams* pEP, size_t uShape, size_t uRotation, size_t uIndexMode) noexcept
{
assert(pEP);
assert(uShape < BC7_MAX_SHAPES);
_Analysis_assume_(uShape < BC7_MAX_SHAPES);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const size_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
assert(uPartitions < BC7_MAX_REGIONS);
_Analysis_assume_(uPartitions < BC7_MAX_REGIONS);
LDREndPntPair aOrgEndPts[BC7_MAX_REGIONS];
LDREndPntPair aOptEndPts[BC7_MAX_REGIONS];
size_t aOrgIdx[NUM_PIXELS_PER_BLOCK];
size_t aOrgIdx2[NUM_PIXELS_PER_BLOCK];
size_t aOptIdx[NUM_PIXELS_PER_BLOCK];
size_t aOptIdx2[NUM_PIXELS_PER_BLOCK];
float aOrgErr[BC7_MAX_REGIONS];
float aOptErr[BC7_MAX_REGIONS];
const LDREndPntPair* aEndPts = &pEP->aEndPts[uShape][0];
for (size_t p = 0; p <= uPartitions; p++)
{
#ifdef __GNUC__
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wstringop-overflow"
#endif
aOrgEndPts[p].A = Quantize(aEndPts[p].A, ms_aInfo[pEP->uMode].RGBAPrecWithP);
aOrgEndPts[p].B = Quantize(aEndPts[p].B, ms_aInfo[pEP->uMode].RGBAPrecWithP);
#ifdef __GNUC_
#pragma GCC diagnostic pop
#endif
}
LDREndPntPair newEndPts1[BC7_MAX_REGIONS];
FixEndpointPBits(pEP, aOrgEndPts, newEndPts1);
AssignIndices(pEP, uShape, uIndexMode, newEndPts1, aOrgIdx, aOrgIdx2, aOrgErr);
OptimizeEndPoints(pEP, uShape, uIndexMode, aOrgErr, newEndPts1, aOptEndPts);
LDREndPntPair newEndPts2[BC7_MAX_REGIONS];
FixEndpointPBits(pEP, aOptEndPts, newEndPts2);
AssignIndices(pEP, uShape, uIndexMode, newEndPts2, aOptIdx, aOptIdx2, aOptErr);
float fOrgTotErr = 0, fOptTotErr = 0;
for (size_t p = 0; p <= uPartitions; p++)
{
fOrgTotErr += aOrgErr[p];
fOptTotErr += aOptErr[p];
}
if (fOptTotErr < fOrgTotErr)
{
EmitBlock(pEP, uShape, uRotation, uIndexMode, newEndPts2, aOptIdx, aOptIdx2);
return fOptTotErr;
}
else
{
EmitBlock(pEP, uShape, uRotation, uIndexMode, newEndPts1, aOrgIdx, aOrgIdx2);
return fOrgTotErr;
}
}
_Use_decl_annotations_
float D3DX_BC7::MapColors(const EncodeParams* pEP, const LDRColorA aColors[], size_t np, size_t uIndexMode, const LDREndPntPair& endPts, float fMinErr) const noexcept
{
assert(pEP);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
const uint8_t uIndexPrec = uIndexMode ? ms_aInfo[pEP->uMode].uIndexPrec2 : ms_aInfo[pEP->uMode].uIndexPrec;
const uint8_t uIndexPrec2 = uIndexMode ? ms_aInfo[pEP->uMode].uIndexPrec : ms_aInfo[pEP->uMode].uIndexPrec2;
LDRColorA aPalette[BC7_MAX_INDICES];
float fTotalErr = 0;
GeneratePaletteQuantized(pEP, uIndexMode, endPts, aPalette);
for (size_t i = 0; i < np; ++i)
{
fTotalErr += ComputeError(aColors[i], aPalette, uIndexPrec, uIndexPrec2);
if (fTotalErr > fMinErr) // check for early exit
{
fTotalErr = FLT_MAX;
break;
}
}
return fTotalErr;
}
_Use_decl_annotations_
float D3DX_BC7::RoughMSE(EncodeParams* pEP, size_t uShape, size_t uIndexMode) noexcept
{
assert(pEP);
assert(uShape < BC7_MAX_SHAPES);
_Analysis_assume_(uShape < BC7_MAX_SHAPES);
assert(pEP->uMode < c_NumModes);
_Analysis_assume_(pEP->uMode < c_NumModes);
LDREndPntPair* aEndPts = pEP->aEndPts[uShape];
const uint8_t uPartitions = ms_aInfo[pEP->uMode].uPartitions;
assert(uPartitions < BC7_MAX_REGIONS);
_Analysis_assume_(uPartitions < BC7_MAX_REGIONS);
const uint8_t uIndexPrec = uIndexMode ? ms_aInfo[pEP->uMode].uIndexPrec2 : ms_aInfo[pEP->uMode].uIndexPrec;
const uint8_t uIndexPrec2 = uIndexMode ? ms_aInfo[pEP->uMode].uIndexPrec : ms_aInfo[pEP->uMode].uIndexPrec2;
auto const uNumIndices = static_cast<const uint8_t>(1u << uIndexPrec);
auto const uNumIndices2 = static_cast<const uint8_t>(1u << uIndexPrec2);
size_t auPixIdx[NUM_PIXELS_PER_BLOCK];
LDRColorA aPalette[BC7_MAX_REGIONS][BC7_MAX_INDICES];
for (size_t p = 0; p <= uPartitions; p++)
{
size_t np = 0;
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++)
{
if (g_aPartitionTable[uPartitions][uShape][i] == p)
{
auPixIdx[np++] = i;
}
}
// handle simple cases
assert(np > 0);
if (np == 1)
{
aEndPts[p].A = pEP->aLDRPixels[auPixIdx[0]];
aEndPts[p].B = pEP->aLDRPixels[auPixIdx[0]];
continue;
}
else if (np == 2)
{
aEndPts[p].A = pEP->aLDRPixels[auPixIdx[0]];
aEndPts[p].B = pEP->aLDRPixels[auPixIdx[1]];
continue;
}
if (uIndexPrec2 == 0)
{
HDRColorA epA, epB;
OptimizeRGBA(pEP->aHDRPixels, &epA, &epB, 4, np, auPixIdx);
epA.Clamp(0.0f, 1.0f);
epB.Clamp(0.0f, 1.0f);
epA *= 255.0f;
epB *= 255.0f;
aEndPts[p].A = epA.ToLDRColorA();
aEndPts[p].B = epB.ToLDRColorA();
}
else
{
uint8_t uMinAlpha = 255, uMaxAlpha = 0;
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; ++i)
{
uMinAlpha = std::min<uint8_t>(uMinAlpha, pEP->aLDRPixels[auPixIdx[i]].a);
uMaxAlpha = std::max<uint8_t>(uMaxAlpha, pEP->aLDRPixels[auPixIdx[i]].a);
}
HDRColorA epA, epB;
OptimizeRGB(pEP->aHDRPixels, &epA, &epB, 4, np, auPixIdx);
epA.Clamp(0.0f, 1.0f);
epB.Clamp(0.0f, 1.0f);
epA *= 255.0f;
epB *= 255.0f;
aEndPts[p].A = epA.ToLDRColorA();
aEndPts[p].B = epB.ToLDRColorA();
aEndPts[p].A.a = uMinAlpha;
aEndPts[p].B.a = uMaxAlpha;
}
}
if (uIndexPrec2 == 0)
{
for (size_t p = 0; p <= uPartitions; p++)
for (size_t i = 0; i < uNumIndices; i++)
LDRColorA::Interpolate(aEndPts[p].A, aEndPts[p].B, i, i, uIndexPrec, uIndexPrec, aPalette[p][i]);
}
else
{
for (size_t p = 0; p <= uPartitions; p++)
{
for (size_t i = 0; i < uNumIndices; i++)
LDRColorA::InterpolateRGB(aEndPts[p].A, aEndPts[p].B, i, uIndexPrec, aPalette[p][i]);
for (size_t i = 0; i < uNumIndices2; i++)
LDRColorA::InterpolateA(aEndPts[p].A, aEndPts[p].B, i, uIndexPrec2, aPalette[p][i]);
}
}
float fTotalErr = 0;
for (size_t i = 0; i < NUM_PIXELS_PER_BLOCK; i++)
{
const uint8_t uRegion = g_aPartitionTable[uPartitions][uShape][i];
fTotalErr += ComputeError(pEP->aLDRPixels[i], aPalette[uRegion], uIndexPrec, uIndexPrec2);
}
return fTotalErr;
}
//=====================================================================================
// Entry points
//=====================================================================================
//-------------------------------------------------------------------------------------
// BC6H Compression
//-------------------------------------------------------------------------------------
_Use_decl_annotations_
void DirectX::D3DXDecodeBC6HU(XMVECTOR *pColor, const uint8_t *pBC) noexcept
{
assert(pColor && pBC);
static_assert(sizeof(D3DX_BC6H) == 16, "D3DX_BC6H should be 16 bytes");
reinterpret_cast<const D3DX_BC6H*>(pBC)->Decode(false, reinterpret_cast<HDRColorA*>(pColor));
}
_Use_decl_annotations_
void DirectX::D3DXDecodeBC6HS(XMVECTOR *pColor, const uint8_t *pBC) noexcept
{
assert(pColor && pBC);
static_assert(sizeof(D3DX_BC6H) == 16, "D3DX_BC6H should be 16 bytes");
reinterpret_cast<const D3DX_BC6H*>(pBC)->Decode(true, reinterpret_cast<HDRColorA*>(pColor));
}
_Use_decl_annotations_
void DirectX::D3DXEncodeBC6HU(uint8_t *pBC, const XMVECTOR *pColor, uint32_t flags) noexcept
{
UNREFERENCED_PARAMETER(flags);
assert(pBC && pColor);
static_assert(sizeof(D3DX_BC6H) == 16, "D3DX_BC6H should be 16 bytes");
reinterpret_cast<D3DX_BC6H*>(pBC)->Encode(false, reinterpret_cast<const HDRColorA*>(pColor));
}
_Use_decl_annotations_
void DirectX::D3DXEncodeBC6HS(uint8_t *pBC, const XMVECTOR *pColor, uint32_t flags) noexcept
{
UNREFERENCED_PARAMETER(flags);
assert(pBC && pColor);
static_assert(sizeof(D3DX_BC6H) == 16, "D3DX_BC6H should be 16 bytes");
reinterpret_cast<D3DX_BC6H*>(pBC)->Encode(true, reinterpret_cast<const HDRColorA*>(pColor));
}
//-------------------------------------------------------------------------------------
// BC7 Compression
//-------------------------------------------------------------------------------------
_Use_decl_annotations_
void DirectX::D3DXDecodeBC7(XMVECTOR *pColor, const uint8_t *pBC) noexcept
{
assert(pColor && pBC);
static_assert(sizeof(D3DX_BC7) == 16, "D3DX_BC7 should be 16 bytes");
reinterpret_cast<const D3DX_BC7*>(pBC)->Decode(reinterpret_cast<HDRColorA*>(pColor));
}
_Use_decl_annotations_
void DirectX::D3DXEncodeBC7(uint8_t *pBC, const XMVECTOR *pColor, uint32_t flags) noexcept
{
assert(pBC && pColor);
static_assert(sizeof(D3DX_BC7) == 16, "D3DX_BC7 should be 16 bytes");
reinterpret_cast<D3DX_BC7*>(pBC)->Encode(flags, reinterpret_cast<const HDRColorA*>(pColor));
}