зеркало из https://github.com/mozilla/gecko-dev.git
162 строки
3.5 KiB
C++
162 строки
3.5 KiB
C++
/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
|
|
* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
#ifndef MOZILLA_GFX_TOOLS_H_
|
|
#define MOZILLA_GFX_TOOLS_H_
|
|
|
|
#include "Types.h"
|
|
#include "Point.h"
|
|
#include <math.h>
|
|
#if defined(_MSC_VER) && (_MSC_VER < 1600)
|
|
#define hypotf _hypotf
|
|
#endif
|
|
|
|
namespace mozilla {
|
|
namespace gfx {
|
|
|
|
static inline bool
|
|
IsOperatorBoundByMask(CompositionOp aOp) {
|
|
switch (aOp) {
|
|
case CompositionOp::OP_IN:
|
|
case CompositionOp::OP_OUT:
|
|
case CompositionOp::OP_DEST_IN:
|
|
case CompositionOp::OP_DEST_ATOP:
|
|
case CompositionOp::OP_SOURCE:
|
|
return false;
|
|
default:
|
|
return true;
|
|
}
|
|
}
|
|
|
|
template <class T>
|
|
struct ClassStorage
|
|
{
|
|
char bytes[sizeof(T)];
|
|
|
|
const T *addr() const { return (const T *)bytes; }
|
|
T *addr() { return (T *)(void *)bytes; }
|
|
};
|
|
|
|
static inline bool
|
|
FuzzyEqual(Float aA, Float aB, Float aErr)
|
|
{
|
|
if ((aA + aErr >= aB) && (aA - aErr <= aB)) {
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static inline void
|
|
NudgeToInteger(float *aVal)
|
|
{
|
|
float r = floorf(*aVal + 0.5f);
|
|
// The error threshold should be proportional to the rounded value. This
|
|
// bounds the relative error introduced by the nudge operation. However,
|
|
// when the rounded value is 0, the error threshold can't be proportional
|
|
// to the rounded value (we'd never round), so we just choose the same
|
|
// threshold as for a rounded value of 1.
|
|
if (FuzzyEqual(r, *aVal, r == 0.0f ? 1e-6f : fabs(r*1e-6f))) {
|
|
*aVal = r;
|
|
}
|
|
}
|
|
|
|
static inline void
|
|
NudgeToInteger(float *aVal, float aErr)
|
|
{
|
|
float r = floorf(*aVal + 0.5f);
|
|
if (FuzzyEqual(r, *aVal, aErr)) {
|
|
*aVal = r;
|
|
}
|
|
}
|
|
|
|
static inline Float
|
|
Distance(Point aA, Point aB)
|
|
{
|
|
return hypotf(aB.x - aA.x, aB.y - aA.y);
|
|
}
|
|
|
|
static inline int
|
|
BytesPerPixel(SurfaceFormat aFormat)
|
|
{
|
|
switch (aFormat) {
|
|
case SurfaceFormat::A8:
|
|
return 1;
|
|
case SurfaceFormat::R5G6B5:
|
|
return 2;
|
|
default:
|
|
return 4;
|
|
}
|
|
}
|
|
|
|
template<typename T, int alignment = 16>
|
|
struct AlignedArray
|
|
{
|
|
AlignedArray()
|
|
: mStorage(nullptr)
|
|
, mPtr(nullptr)
|
|
{
|
|
}
|
|
|
|
MOZ_ALWAYS_INLINE AlignedArray(size_t aSize)
|
|
: mStorage(nullptr)
|
|
{
|
|
Realloc(aSize);
|
|
}
|
|
|
|
MOZ_ALWAYS_INLINE ~AlignedArray()
|
|
{
|
|
delete [] mStorage;
|
|
}
|
|
|
|
void Dealloc()
|
|
{
|
|
delete [] mStorage;
|
|
mStorage = mPtr = nullptr;
|
|
}
|
|
|
|
MOZ_ALWAYS_INLINE void Realloc(size_t aSize)
|
|
{
|
|
delete [] mStorage;
|
|
mStorage = new (std::nothrow) T[aSize + (alignment - 1)];
|
|
if (uintptr_t(mStorage) % alignment) {
|
|
// Our storage does not start at a <alignment>-byte boundary. Make sure mData does!
|
|
mPtr = (T*)(uintptr_t(mStorage) +
|
|
(alignment - (uintptr_t(mStorage) % alignment)));
|
|
} else {
|
|
mPtr = mStorage;
|
|
}
|
|
}
|
|
|
|
MOZ_ALWAYS_INLINE operator T*()
|
|
{
|
|
return mPtr;
|
|
}
|
|
|
|
T *mStorage;
|
|
T *mPtr;
|
|
};
|
|
|
|
/**
|
|
* Returns aStride increased, if necessary, so that it divides exactly into
|
|
* |alignment|.
|
|
*
|
|
* Note that currently |alignment| must be a power-of-2. If for some reason we
|
|
* want to support NPOT alignment we can revert back to this functions old
|
|
* implementation.
|
|
*/
|
|
template<int alignment>
|
|
int32_t GetAlignedStride(int32_t aStride)
|
|
{
|
|
static_assert(alignment > 0 && (alignment & (alignment-1)) == 0,
|
|
"This implementation currently require power-of-two alignment");
|
|
const int32_t mask = alignment - 1;
|
|
return (aStride + mask) & ~mask;
|
|
}
|
|
|
|
}
|
|
}
|
|
|
|
#endif /* MOZILLA_GFX_TOOLS_H_ */
|