static bool
_get_rectangular_clip (cairo_t *cr,
const nsIntRect& bounds,
bool *need_clip,
nsIntRect *rectangles, int max_rectangles,
int *num_rectangles)
{
cairo_rectangle_list_t *cliplist;
cairo_rectangle_t *clips;
int i;
bool retval = true;
cliplist = cairo_copy_clip_rectangle_list (cr);
if (cliplist->status != CAIRO_STATUS_SUCCESS) {
retval = false;
NATIVE_DRAWING_NOTE("FALLBACK: non-rectangular clip");
goto FINISH;
}
/* the clip is always in surface backend coordinates (i.e. native backend coords) */
clips = cliplist->rectangles;
for (i = 0; i < cliplist->num_rectangles; ++i) {
nsIntRect rect;
if (!_convert_coord_to_int (clips[i].x, &rect.x) ||
!_convert_coord_to_int (clips[i].y, &rect.y) ||
!_convert_coord_to_int (clips[i].width, &rect.width) ||
!_convert_coord_to_int (clips[i].height, &rect.height))
{
retval = false;
NATIVE_DRAWING_NOTE("FALLBACK: non-integer clip");
goto FINISH;
}
if (rect.IsEqualInterior(bounds)) {
/* the bounds are entirely inside the clip region so we don't need to clip. */
*need_clip = false;
goto FINISH;
}
NS_ASSERTION(bounds.Contains(rect),
"Was expecting to be clipped to bounds");
if (i >= max_rectangles) {
retval = false;
NATIVE_DRAWING_NOTE("FALLBACK: unsupported clip rectangle count");
goto FINISH;
}
rectangles[i] = rect;
}
*need_clip = true;
*num_rectangles = cliplist->num_rectangles;
FINISH:
cairo_rectangle_list_destroy (cliplist);
return retval;
}
void
gfxImageSurface::MovePixels(const nsIntRect& aSourceRect,
const nsIntPoint& aDestTopLeft)
{
const nsIntRect bounds(0, 0, mSize.width, mSize.height);
nsIntPoint offset = aDestTopLeft - aSourceRect.TopLeft();
nsIntRect clippedSource = aSourceRect;
clippedSource.IntersectRect(clippedSource, bounds);
nsIntRect clippedDest = clippedSource + offset;
clippedDest.IntersectRect(clippedDest, bounds);
const nsIntRect dest = clippedDest;
const nsIntRect source = dest - offset;
// NB: this relies on IntersectRect() and operator+/- preserving
// x/y for empty rectangles
NS_ABORT_IF_FALSE(bounds.Contains(dest) && bounds.Contains(source) &&
aSourceRect.Contains(source) &&
nsIntRect(aDestTopLeft, aSourceRect.Size()).Contains(dest) &&
source.Size() == dest.Size() &&
offset == (dest.TopLeft() - source.TopLeft()),
"Messed up clipping, crash or corruption will follow");
if (source.IsEmpty() || source.IsEqualInterior(dest)) {
return;
}
long naturalStride = ComputeStride(mSize, mFormat);
if (mStride == naturalStride && dest.width == bounds.width) {
// Fast path: this is a vertical shift of some rows in a
// "normal" image surface. We can directly memmove and
// hopefully stay in SIMD land.
unsigned char* dst = mData + dest.y * mStride;
const unsigned char* src = mData + source.y * mStride;
size_t nBytes = dest.height * mStride;
memmove(dst, src, nBytes);
return;
}
// Slow(er) path: have to move row-by-row.
const int32_t bpp = BytePerPixelFromFormat(mFormat);
const size_t nRowBytes = dest.width * bpp;
// dstRow points at the first pixel within the current destination
// row, and similarly for srcRow. endSrcRow is one row beyond the
// last row we need to copy. stride is either +mStride or
// -mStride, depending on which direction we're copying.
unsigned char* dstRow;
unsigned char* srcRow;
unsigned char* endSrcRow; // NB: this may point outside the image
long stride;
if (dest.y > source.y) {
// We're copying down from source to dest, so walk backwards
// starting from the last rows to avoid stomping pixels we
// need.
stride = -mStride;
dstRow = mData + dest.x * bpp + (dest.YMost() - 1) * mStride;
srcRow = mData + source.x * bpp + (source.YMost() - 1) * mStride;
endSrcRow = mData + source.x * bpp + (source.y - 1) * mStride;
} else {
stride = mStride;
dstRow = mData + dest.x * bpp + dest.y * mStride;
srcRow = mData + source.x * bpp + source.y * mStride;
endSrcRow = mData + source.x * bpp + source.YMost() * mStride;
}
for (; srcRow != endSrcRow; dstRow += stride, srcRow += stride) {
memmove(dstRow, srcRow, nRowBytes);
}
}