gecko-dev/gfx/2d/BufferEdgePad.cpp

105 строки
3.4 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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/. */
#include "BufferEdgePad.h"
#include "2D.h" // for DrawTarget
#include "Point.h" // for IntSize
#include "Types.h" // for SurfaceFormat
#include "nsRegion.h"
namespace mozilla {
namespace gfx {
void PadDrawTargetOutFromRegion(DrawTarget *aDrawTarget,
const nsIntRegion &aRegion) {
struct LockedBits {
uint8_t *data;
IntSize size;
int32_t stride;
SurfaceFormat format;
static int clamp(int x, int min, int max) {
if (x < min) x = min;
if (x > max) x = max;
return x;
}
static void ensure_memcpy(uint8_t *dst, uint8_t *src, size_t n,
uint8_t *bitmap, int stride, int height) {
if (src + n > bitmap + stride * height) {
MOZ_CRASH("GFX: long src memcpy");
}
if (src < bitmap) {
MOZ_CRASH("GFX: short src memcpy");
}
if (dst + n > bitmap + stride * height) {
MOZ_CRASH("GFX: long dst mempcy");
}
if (dst < bitmap) {
MOZ_CRASH("GFX: short dst mempcy");
}
}
static void visitor(void *closure, VisitSide side, int x1, int y1, int x2,
int y2) {
LockedBits *lb = static_cast<LockedBits *>(closure);
uint8_t *bitmap = lb->data;
const int bpp = gfx::BytesPerPixel(lb->format);
const int stride = lb->stride;
const int width = lb->size.width;
const int height = lb->size.height;
if (side == VisitSide::TOP) {
if (y1 > 0) {
x1 = clamp(x1, 0, width - 1);
x2 = clamp(x2, 0, width - 1);
ensure_memcpy(&bitmap[x1 * bpp + (y1 - 1) * stride],
&bitmap[x1 * bpp + y1 * stride], (x2 - x1) * bpp,
bitmap, stride, height);
memcpy(&bitmap[x1 * bpp + (y1 - 1) * stride],
&bitmap[x1 * bpp + y1 * stride], (x2 - x1) * bpp);
}
} else if (side == VisitSide::BOTTOM) {
if (y1 < height) {
x1 = clamp(x1, 0, width - 1);
x2 = clamp(x2, 0, width - 1);
ensure_memcpy(&bitmap[x1 * bpp + y1 * stride],
&bitmap[x1 * bpp + (y1 - 1) * stride], (x2 - x1) * bpp,
bitmap, stride, height);
memcpy(&bitmap[x1 * bpp + y1 * stride],
&bitmap[x1 * bpp + (y1 - 1) * stride], (x2 - x1) * bpp);
}
} else if (side == VisitSide::LEFT) {
if (x1 > 0) {
while (y1 != y2) {
memcpy(&bitmap[(x1 - 1) * bpp + y1 * stride],
&bitmap[x1 * bpp + y1 * stride], bpp);
y1++;
}
}
} else if (side == VisitSide::RIGHT) {
if (x1 < width) {
while (y1 != y2) {
memcpy(&bitmap[x1 * bpp + y1 * stride],
&bitmap[(x1 - 1) * bpp + y1 * stride], bpp);
y1++;
}
}
}
}
} lb;
if (aDrawTarget->LockBits(&lb.data, &lb.size, &lb.stride, &lb.format)) {
// we can only pad software targets so if we can't lock the bits don't pad
aRegion.VisitEdges(lb.visitor, &lb);
aDrawTarget->ReleaseBits(lb.data);
}
}
} // namespace gfx
} // namespace mozilla