gecko-dev/gfx/thebes/gfxImageSurface.cpp
2012-06-15 10:00:44 +12:00

348 lines
11 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* 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 "prmem.h"
#include "gfxAlphaRecovery.h"
#include "gfxImageSurface.h"
#include "cairo.h"
#include "mozilla/gfx/2D.h"
#include "gfx2DGlue.h"
using namespace mozilla::gfx;
gfxImageSurface::gfxImageSurface()
: mSize(0, 0),
mOwnsData(false),
mFormat(ImageFormatUnknown),
mStride(0)
{
}
void
gfxImageSurface::InitFromSurface(cairo_surface_t *csurf)
{
mSize.width = cairo_image_surface_get_width(csurf);
mSize.height = cairo_image_surface_get_height(csurf);
mData = cairo_image_surface_get_data(csurf);
mFormat = (gfxImageFormat) cairo_image_surface_get_format(csurf);
mOwnsData = false;
mStride = cairo_image_surface_get_stride(csurf);
Init(csurf, true);
}
gfxImageSurface::gfxImageSurface(unsigned char *aData, const gfxIntSize& aSize,
long aStride, gfxImageFormat aFormat)
{
InitWithData(aData, aSize, aStride, aFormat);
}
void
gfxImageSurface::MakeInvalid()
{
mSize = gfxIntSize(-1, -1);
mData = NULL;
mStride = 0;
}
void
gfxImageSurface::InitWithData(unsigned char *aData, const gfxIntSize& aSize,
long aStride, gfxImageFormat aFormat)
{
mSize = aSize;
mOwnsData = false;
mData = aData;
mFormat = aFormat;
mStride = aStride;
if (!CheckSurfaceSize(aSize))
MakeInvalid();
cairo_surface_t *surface =
cairo_image_surface_create_for_data((unsigned char*)mData,
(cairo_format_t)mFormat,
mSize.width,
mSize.height,
mStride);
// cairo_image_surface_create_for_data can return a 'null' surface
// in out of memory conditions. The gfxASurface::Init call checks
// the surface it receives to see if there is an error with the
// surface and handles it appropriately. That is why there is
// no check here.
Init(surface);
}
static void*
TryAllocAlignedBytes(size_t aSize)
{
// Use fallible allocators here
#if defined(HAVE_POSIX_MEMALIGN)
void* ptr;
// Try to align for fast alpha recovery. This should only help
// cairo too, can't hurt.
return moz_posix_memalign(&ptr,
1 << gfxAlphaRecovery::GoodAlignmentLog2(),
aSize) ?
nsnull : ptr;
#else
// Oh well, hope that luck is with us in the allocator
return moz_malloc(aSize);
#endif
}
gfxImageSurface::gfxImageSurface(const gfxIntSize& size, gfxImageFormat format, bool aClear) :
mSize(size), mOwnsData(false), mData(nsnull), mFormat(format)
{
mStride = ComputeStride();
if (!CheckSurfaceSize(size))
MakeInvalid();
// if we have a zero-sized surface, just leave mData nsnull
if (mSize.height * mStride > 0) {
// This can fail to allocate memory aligned as we requested,
// or it can fail to allocate any memory at all.
mData = (unsigned char *) TryAllocAlignedBytes(mSize.height * mStride);
if (!mData)
return;
if (aClear)
memset(mData, 0, mSize.height * mStride);
}
mOwnsData = true;
cairo_surface_t *surface =
cairo_image_surface_create_for_data((unsigned char*)mData,
(cairo_format_t)format,
mSize.width,
mSize.height,
mStride);
Init(surface);
if (mSurfaceValid) {
RecordMemoryUsed(mSize.height * ComputeStride() +
sizeof(gfxImageSurface));
}
}
gfxImageSurface::gfxImageSurface(cairo_surface_t *csurf)
{
mSize.width = cairo_image_surface_get_width(csurf);
mSize.height = cairo_image_surface_get_height(csurf);
mData = cairo_image_surface_get_data(csurf);
mFormat = (gfxImageFormat) cairo_image_surface_get_format(csurf);
mOwnsData = false;
mStride = cairo_image_surface_get_stride(csurf);
Init(csurf, true);
}
gfxImageSurface::~gfxImageSurface()
{
if (mOwnsData)
free(mData);
}
/*static*/ long
gfxImageSurface::ComputeStride(const gfxIntSize& aSize, gfxImageFormat aFormat)
{
long stride;
if (aFormat == ImageFormatARGB32)
stride = aSize.width * 4;
else if (aFormat == ImageFormatRGB24)
stride = aSize.width * 4;
else if (aFormat == ImageFormatRGB16_565)
stride = aSize.width * 2;
else if (aFormat == ImageFormatA8)
stride = aSize.width;
else if (aFormat == ImageFormatA1) {
stride = (aSize.width + 7) / 8;
} else {
NS_WARNING("Unknown format specified to gfxImageSurface!");
stride = aSize.width * 4;
}
stride = ((stride + 3) / 4) * 4;
return stride;
}
// helper function for the CopyFrom methods
static void
CopyForStride(unsigned char* aDest, unsigned char* aSrc, const gfxIntSize& aSize, long aDestStride, long aSrcStride)
{
if (aDestStride == aSrcStride) {
memcpy (aDest, aSrc, aSrcStride * aSize.height);
} else {
int lineSize = NS_MIN(aDestStride, aSrcStride);
for (int i = 0; i < aSize.height; i++) {
unsigned char* src = aSrc + aSrcStride * i;
unsigned char* dst = aDest + aDestStride * i;
memcpy (dst, src, lineSize);
}
}
}
// helper function for the CopyFrom methods
static bool
FormatsAreCompatible(gfxASurface::gfxImageFormat a1, gfxASurface::gfxImageFormat a2)
{
if (a1 != a2 &&
!(a1 == gfxASurface::ImageFormatARGB32 &&
a2 == gfxASurface::ImageFormatRGB24) &&
!(a1 == gfxASurface::ImageFormatRGB24 &&
a2 == gfxASurface::ImageFormatARGB32)) {
return false;
}
return true;
}
bool
gfxImageSurface::CopyFrom (SourceSurface *aSurface)
{
mozilla::RefPtr<DataSourceSurface> data = aSurface->GetDataSurface();
if (!data) {
return false;
}
gfxIntSize size(data->GetSize().width, data->GetSize().height);
if (size != mSize) {
return false;
}
if (!FormatsAreCompatible(SurfaceFormatToImageFormat(aSurface->GetFormat()),
mFormat)) {
return false;
}
CopyForStride(mData, data->GetData(), size, mStride, data->Stride());
return true;
}
bool
gfxImageSurface::CopyFrom(gfxImageSurface *other)
{
if (other->mSize != mSize) {
return false;
}
if (!FormatsAreCompatible(other->mFormat, mFormat)) {
return false;
}
CopyForStride(mData, other->mData, mSize, mStride, other->mStride);
return true;
}
already_AddRefed<gfxSubimageSurface>
gfxImageSurface::GetSubimage(const gfxRect& aRect)
{
gfxRect r(aRect);
r.Round();
unsigned char* subData = Data() +
(Stride() * (int)r.Y()) +
(int)r.X() * gfxASurface::BytePerPixelFromFormat(Format());
nsRefPtr<gfxSubimageSurface> image =
new gfxSubimageSurface(this, subData,
gfxIntSize((int)r.Width(), (int)r.Height()));
return image.forget().get();
}
gfxSubimageSurface::gfxSubimageSurface(gfxImageSurface* aParent,
unsigned char* aData,
const gfxIntSize& aSize)
: gfxImageSurface(aData, aSize, aParent->Stride(), aParent->Format())
, mParent(aParent)
{
}
already_AddRefed<gfxImageSurface>
gfxImageSurface::GetAsImageSurface()
{
nsRefPtr<gfxImageSurface> surface = this;
return surface.forget();
}
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 PRInt32 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);
}
}