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

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/* -*- 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/. */
#include "BorrowedContext.h"
#include "DataSurfaceHelpers.h"
#include "DrawTargetCG.h"
#include "Logging.h"
#include "SourceSurfaceCG.h"
#include "Rect.h"
#include "ScaledFontMac.h"
#include "Tools.h"
#include "PathHelpers.h"
#include <vector>
#include <algorithm>
#include "MacIOSurface.h"
#include "FilterNodeSoftware.h"
#include "mozilla/Assertions.h"
#include "mozilla/FloatingPoint.h"
#include "mozilla/Types.h" // for decltype
#include "mozilla/Vector.h"
using namespace std;
//CG_EXTERN void CGContextSetCompositeOperation (CGContextRef, PrivateCGCompositeMode);
// A private API that Cairo has been using for a long time
CG_EXTERN void CGContextSetCTM(CGContextRef, CGAffineTransform);
namespace mozilla {
namespace gfx {
template <typename T>
static CGRect RectToCGRect(const T& r)
{
return CGRectMake(r.x, r.y, r.width, r.height);
}
CGBlendMode ToBlendMode(CompositionOp op)
{
CGBlendMode mode;
switch (op) {
case CompositionOp::OP_OVER:
mode = kCGBlendModeNormal;
break;
case CompositionOp::OP_ADD:
mode = kCGBlendModePlusLighter;
break;
case CompositionOp::OP_ATOP:
mode = kCGBlendModeSourceAtop;
break;
case CompositionOp::OP_OUT:
mode = kCGBlendModeSourceOut;
break;
case CompositionOp::OP_IN:
mode = kCGBlendModeSourceIn;
break;
case CompositionOp::OP_SOURCE:
mode = kCGBlendModeCopy;
break;
case CompositionOp::OP_DEST_IN:
mode = kCGBlendModeDestinationIn;
break;
case CompositionOp::OP_DEST_OUT:
mode = kCGBlendModeDestinationOut;
break;
case CompositionOp::OP_DEST_OVER:
mode = kCGBlendModeDestinationOver;
break;
case CompositionOp::OP_DEST_ATOP:
mode = kCGBlendModeDestinationAtop;
break;
case CompositionOp::OP_XOR:
mode = kCGBlendModeXOR;
break;
case CompositionOp::OP_MULTIPLY:
mode = kCGBlendModeMultiply;
break;
case CompositionOp::OP_SCREEN:
mode = kCGBlendModeScreen;
break;
case CompositionOp::OP_OVERLAY:
mode = kCGBlendModeOverlay;
break;
case CompositionOp::OP_DARKEN:
mode = kCGBlendModeDarken;
break;
case CompositionOp::OP_LIGHTEN:
mode = kCGBlendModeLighten;
break;
case CompositionOp::OP_COLOR_DODGE:
mode = kCGBlendModeColorDodge;
break;
case CompositionOp::OP_COLOR_BURN:
mode = kCGBlendModeColorBurn;
break;
case CompositionOp::OP_HARD_LIGHT:
mode = kCGBlendModeHardLight;
break;
case CompositionOp::OP_SOFT_LIGHT:
mode = kCGBlendModeSoftLight;
break;
case CompositionOp::OP_DIFFERENCE:
mode = kCGBlendModeDifference;
break;
case CompositionOp::OP_EXCLUSION:
mode = kCGBlendModeExclusion;
break;
case CompositionOp::OP_HUE:
mode = kCGBlendModeHue;
break;
case CompositionOp::OP_SATURATION:
mode = kCGBlendModeSaturation;
break;
case CompositionOp::OP_COLOR:
mode = kCGBlendModeColor;
break;
case CompositionOp::OP_LUMINOSITY:
mode = kCGBlendModeLuminosity;
break;
/*
case OP_CLEAR:
mode = kCGBlendModeClear;
break;*/
default:
mode = kCGBlendModeNormal;
}
return mode;
}
static CGInterpolationQuality
InterpolationQualityFromFilter(Filter aFilter)
{
switch (aFilter) {
default:
case Filter::LINEAR:
return kCGInterpolationLow;
case Filter::POINT:
return kCGInterpolationNone;
case Filter::GOOD:
return kCGInterpolationLow;
}
}
DrawTargetCG::DrawTargetCG()
: mColorSpace(nullptr)
, mCg(nullptr)
, mMayContainInvalidPremultipliedData(false)
{
}
DrawTargetCG::~DrawTargetCG()
{
if (mSnapshot) {
if (mSnapshot->refCount() > 1) {
// We only need to worry about snapshots that someone else knows about
mSnapshot->DrawTargetWillGoAway();
}
mSnapshot = nullptr;
}
// Both of these are OK with nullptr arguments, so we do not
// need to check (these could be nullptr if Init fails)
CGColorSpaceRelease(mColorSpace);
CGContextRelease(mCg);
}
DrawTargetType
DrawTargetCG::GetType() const
{
return GetBackendType() == BackendType::COREGRAPHICS_ACCELERATED ?
DrawTargetType::HARDWARE_RASTER : DrawTargetType::SOFTWARE_RASTER;
}
BackendType
DrawTargetCG::GetBackendType() const
{
// It may be worth spliting Bitmap and IOSurface DrawTarget
// into seperate classes.
if (GetContextType(mCg) == CG_CONTEXT_TYPE_IOSURFACE) {
return BackendType::COREGRAPHICS_ACCELERATED;
} else {
return BackendType::COREGRAPHICS;
}
}
TemporaryRef<SourceSurface>
DrawTargetCG::Snapshot()
{
if (!mSnapshot) {
if (GetContextType(mCg) == CG_CONTEXT_TYPE_IOSURFACE) {
return new SourceSurfaceCGIOSurfaceContext(this);
}
Flush();
mSnapshot = new SourceSurfaceCGBitmapContext(this);
}
return mSnapshot;
}
TemporaryRef<DrawTarget>
DrawTargetCG::CreateSimilarDrawTarget(const IntSize &aSize, SurfaceFormat aFormat) const
{
// XXX: in thebes we use CGLayers to do this kind of thing. It probably makes sense
// to add that in somehow, but at a higher level
RefPtr<DrawTargetCG> newTarget = new DrawTargetCG();
if (newTarget->Init(GetBackendType(), aSize, aFormat)) {
return newTarget.forget();
}
return nullptr;
}
TemporaryRef<SourceSurface>
DrawTargetCG::CreateSourceSurfaceFromData(unsigned char *aData,
const IntSize &aSize,
int32_t aStride,
SurfaceFormat aFormat) const
{
RefPtr<SourceSurfaceCG> newSurf = new SourceSurfaceCG();
if (!newSurf->InitFromData(aData, aSize, aStride, aFormat)) {
return nullptr;
}
return newSurf.forget();
}
static void releaseDataSurface(void* info, const void *data, size_t size)
{
static_cast<DataSourceSurface*>(info)->Release();
}
// This function returns a retained CGImage that needs to be released after
// use. The reason for this is that we want to either reuse an existing CGImage
// or create a new one.
static CGImageRef
GetRetainedImageFromSourceSurface(SourceSurface *aSurface)
{
switch(aSurface->GetType()) {
case SurfaceType::COREGRAPHICS_IMAGE:
return CGImageRetain(static_cast<SourceSurfaceCG*>(aSurface)->GetImage());
case SurfaceType::COREGRAPHICS_CGCONTEXT:
return CGImageRetain(static_cast<SourceSurfaceCGContext*>(aSurface)->GetImage());
default:
{
RefPtr<DataSourceSurface> data = aSurface->GetDataSurface();
if (!data) {
MOZ_CRASH("unsupported source surface");
}
data->AddRef();
return CreateCGImage(releaseDataSurface, data.get(),
data->GetData(), data->GetSize(),
data->Stride(), data->GetFormat());
}
}
}
TemporaryRef<SourceSurface>
DrawTargetCG::OptimizeSourceSurface(SourceSurface *aSurface) const
{
return aSurface;
}
class UnboundnessFixer
{
CGRect mClipBounds;
CGLayerRef mLayer;
CGContextRef mLayerCg;
public:
UnboundnessFixer() : mLayerCg(nullptr) {}
CGContextRef Check(CGContextRef baseCg, CompositionOp blend, const Rect* maskBounds = nullptr)
{
MOZ_ASSERT(baseCg);
if (!IsOperatorBoundByMask(blend)) {
mClipBounds = CGContextGetClipBoundingBox(baseCg);
// If we're entirely clipped out or if the drawing operation covers the entire clip then
// we don't need to create a temporary surface.
if (CGRectIsEmpty(mClipBounds) ||
(maskBounds && maskBounds->Contains(CGRectToRect(mClipBounds)))) {
return baseCg;
}
// TransparencyLayers aren't blended using the blend mode so
// we are forced to use CGLayers
//XXX: The size here is in default user space units, of the layer relative to the graphics context.
// is the clip bounds still correct if, for example, we have a scale applied to the context?
mLayer = CGLayerCreateWithContext(baseCg, mClipBounds.size, nullptr);
mLayerCg = CGLayerGetContext(mLayer);
// CGContext's default to have the origin at the bottom left
// so flip it to the top left and adjust for the origin
// of the layer
if (MOZ2D_ERROR_IF(!mLayerCg)) {
return nullptr;
}
CGContextTranslateCTM(mLayerCg, -mClipBounds.origin.x, mClipBounds.origin.y + mClipBounds.size.height);
CGContextScaleCTM(mLayerCg, 1, -1);
return mLayerCg;
} else {
return baseCg;
}
}
void Fix(CGContextRef baseCg)
{
if (mLayerCg) {
// we pushed a layer so draw it to baseCg
MOZ_ASSERT(baseCg);
CGContextTranslateCTM(baseCg, 0, mClipBounds.size.height);
CGContextScaleCTM(baseCg, 1, -1);
mClipBounds.origin.y *= -1;
CGContextDrawLayerAtPoint(baseCg, mClipBounds.origin, mLayer);
CGContextRelease(mLayerCg);
}
}
};
void
DrawTargetCG::DrawSurface(SourceSurface *aSurface,
const Rect &aDest,
const Rect &aSource,
const DrawSurfaceOptions &aSurfOptions,
const DrawOptions &aDrawOptions)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
MarkChanged();
CGContextSaveGState(mCg);
CGContextSetBlendMode(mCg, ToBlendMode(aDrawOptions.mCompositionOp));
UnboundnessFixer fixer;
CGContextRef cg = fixer.Check(mCg, aDrawOptions.mCompositionOp, &aDest);
if (MOZ2D_ERROR_IF(!cg)) {
return;
}
CGContextSetAlpha(cg, aDrawOptions.mAlpha);
CGContextSetShouldAntialias(cg, aDrawOptions.mAntialiasMode != AntialiasMode::NONE);
CGContextConcatCTM(cg, GfxMatrixToCGAffineTransform(mTransform));
CGContextSetInterpolationQuality(cg, InterpolationQualityFromFilter(aSurfOptions.mFilter));
CGImageRef image = GetRetainedImageFromSourceSurface(aSurface);
if (aSurfOptions.mFilter == Filter::POINT) {
CGImageRef subimage = CGImageCreateWithImageInRect(image, RectToCGRect(aSource));
CGImageRelease(image);
CGContextScaleCTM(cg, 1, -1);
CGRect flippedRect = CGRectMake(aDest.x, -(aDest.y + aDest.height),
aDest.width, aDest.height);
CGContextDrawImage(cg, flippedRect, subimage);
CGImageRelease(subimage);
} else {
CGRect destRect = CGRectMake(aDest.x, aDest.y, aDest.width, aDest.height);
CGContextClipToRect(cg, destRect);
float xScale = aSource.width / aDest.width;
float yScale = aSource.height / aDest.height;
CGContextTranslateCTM(cg, aDest.x - aSource.x / xScale, aDest.y - aSource.y / yScale);
CGRect adjustedDestRect = CGRectMake(0, 0, CGImageGetWidth(image) / xScale,
CGImageGetHeight(image) / yScale);
CGContextTranslateCTM(cg, 0, CGRectGetHeight(adjustedDestRect));
CGContextScaleCTM(cg, 1, -1);
CGContextDrawImage(cg, adjustedDestRect, image);
CGImageRelease(image);
}
fixer.Fix(mCg);
CGContextRestoreGState(mCg);
}
TemporaryRef<FilterNode>
DrawTargetCG::CreateFilter(FilterType aType)
{
return FilterNodeSoftware::Create(aType);
}
void
DrawTargetCG::DrawFilter(FilterNode *aNode,
const Rect &aSourceRect,
const Point &aDestPoint,
const DrawOptions &aOptions)
{
FilterNodeSoftware* filter = static_cast<FilterNodeSoftware*>(aNode);
filter->Draw(this, aSourceRect, aDestPoint, aOptions);
}
static CGColorRef ColorToCGColor(CGColorSpaceRef aColorSpace, const Color& aColor)
{
CGFloat components[4] = {aColor.r, aColor.g, aColor.b, aColor.a};
return CGColorCreate(aColorSpace, components);
}
class GradientStopsCG : public GradientStops
{
public:
MOZ_DECLARE_REFCOUNTED_VIRTUAL_TYPENAME(GradientStopsCG)
GradientStopsCG(CGColorSpaceRef aColorSpace,
const std::vector<GradientStop>& aStops,
ExtendMode aExtendMode)
: mGradient(nullptr)
{
// This all works fine with empty aStops vector
mExtend = aExtendMode;
if (aExtendMode == ExtendMode::CLAMP) {
size_t numStops = aStops.size();
std::vector<CGFloat> colors;
std::vector<CGFloat> offsets;
colors.reserve(numStops*4);
offsets.reserve(numStops);
for (size_t i = 0; i < numStops; i++) {
colors.push_back(aStops[i].color.r);
colors.push_back(aStops[i].color.g);
colors.push_back(aStops[i].color.b);
colors.push_back(aStops[i].color.a);
offsets.push_back(aStops[i].offset);
}
mGradient = CGGradientCreateWithColorComponents(aColorSpace,
&colors.front(),
&offsets.front(),
offsets.size());
} else {
mStops = aStops;
}
}
virtual ~GradientStopsCG() {
// CGGradientRelease is OK with nullptr argument
CGGradientRelease(mGradient);
}
// Will always report BackendType::COREGRAPHICS, but it is compatible
// with BackendType::COREGRAPHICS_ACCELERATED
BackendType GetBackendType() const { return BackendType::COREGRAPHICS; }
// XXX this should be a union
CGGradientRef mGradient;
std::vector<GradientStop> mStops;
ExtendMode mExtend;
};
TemporaryRef<GradientStops>
DrawTargetCG::CreateGradientStops(GradientStop *aStops, uint32_t aNumStops,
ExtendMode aExtendMode) const
{
std::vector<GradientStop> stops(aStops, aStops+aNumStops);
return new GradientStopsCG(mColorSpace, stops, aExtendMode);
}
static void
UpdateLinearParametersToIncludePoint(double *min_t, double *max_t,
CGPoint *start,
double dx, double dy,
double x, double y)
{
MOZ_ASSERT(IsFinite(x) && IsFinite(y));
/**
* Compute a parameter t such that a line perpendicular to the (dx,dy)
* vector, passing through (start->x + dx*t, start->y + dy*t), also
* passes through (x,y).
*
* Let px = x - start->x, py = y - start->y.
* t is given by
* (px - dx*t)*dx + (py - dy*t)*dy = 0
*
* Solving for t we get
* numerator = dx*px + dy*py
* denominator = dx^2 + dy^2
* t = numerator/denominator
*
* In CalculateRepeatingGradientParams we know the length of (dx,dy)
* is not zero. (This is checked in DrawLinearRepeatingGradient.)
*/
double px = x - start->x;
double py = y - start->y;
double numerator = dx * px + dy * py;
double denominator = dx * dx + dy * dy;
double t = numerator / denominator;
if (*min_t > t) {
*min_t = t;
}
if (*max_t < t) {
*max_t = t;
}
}
/**
* Repeat the gradient line such that lines extended perpendicular to the
* gradient line at both start and end would completely enclose the drawing
* extents.
*/
static void
CalculateRepeatingGradientParams(CGPoint *aStart, CGPoint *aEnd,
CGRect aExtents, int *aRepeatStartFactor,
int *aRepeatEndFactor)
{
double t_min = INFINITY;
double t_max = -INFINITY;
double dx = aEnd->x - aStart->x;
double dy = aEnd->y - aStart->y;
double bounds_x1 = aExtents.origin.x;
double bounds_y1 = aExtents.origin.y;
double bounds_x2 = aExtents.origin.x + aExtents.size.width;
double bounds_y2 = aExtents.origin.y + aExtents.size.height;
UpdateLinearParametersToIncludePoint(&t_min, &t_max, aStart, dx, dy,
bounds_x1, bounds_y1);
UpdateLinearParametersToIncludePoint(&t_min, &t_max, aStart, dx, dy,
bounds_x2, bounds_y1);
UpdateLinearParametersToIncludePoint(&t_min, &t_max, aStart, dx, dy,
bounds_x2, bounds_y2);
UpdateLinearParametersToIncludePoint(&t_min, &t_max, aStart, dx, dy,
bounds_x1, bounds_y2);
MOZ_ASSERT(!isinf(t_min) && !isinf(t_max),
"The first call to UpdateLinearParametersToIncludePoint should have made t_min and t_max non-infinite.");
// Move t_min and t_max to the nearest usable integer to try to avoid
// subtle variations due to numerical instability, especially accidentally
// cutting off a pixel. Extending the gradient repetitions is always safe.
t_min = floor (t_min);
t_max = ceil (t_max);
aEnd->x = aStart->x + dx * t_max;
aEnd->y = aStart->y + dy * t_max;
aStart->x = aStart->x + dx * t_min;
aStart->y = aStart->y + dy * t_min;
*aRepeatStartFactor = t_min;
*aRepeatEndFactor = t_max;
}
static CGGradientRef
CreateRepeatingGradient(CGColorSpaceRef aColorSpace,
CGContextRef cg, GradientStopsCG* aStops,
int aRepeatStartFactor, int aRepeatEndFactor,
bool aReflect)
{
int repeatCount = aRepeatEndFactor - aRepeatStartFactor;
uint32_t stopCount = aStops->mStops.size();
double scale = 1./repeatCount;
std::vector<CGFloat> colors;
std::vector<CGFloat> offsets;
colors.reserve(stopCount*repeatCount*4);
offsets.reserve(stopCount*repeatCount);
for (int j = aRepeatStartFactor; j < aRepeatEndFactor; j++) {
bool isReflected = aReflect && (j % 2) != 0;
for (uint32_t i = 0; i < stopCount; i++) {
uint32_t stopIndex = isReflected ? stopCount - i - 1 : i;
colors.push_back(aStops->mStops[stopIndex].color.r);
colors.push_back(aStops->mStops[stopIndex].color.g);
colors.push_back(aStops->mStops[stopIndex].color.b);
colors.push_back(aStops->mStops[stopIndex].color.a);
CGFloat offset = aStops->mStops[stopIndex].offset;
if (isReflected) {
offset = 1 - offset;
}
offsets.push_back((offset + (j - aRepeatStartFactor)) * scale);
}
}
CGGradientRef gradient = CGGradientCreateWithColorComponents(aColorSpace,
&colors.front(),
&offsets.front(),
repeatCount*stopCount);
return gradient;
}
static void
DrawLinearRepeatingGradient(CGColorSpaceRef aColorSpace, CGContextRef cg,
const LinearGradientPattern &aPattern,
const CGRect &aExtents, bool aReflect)
{
GradientStopsCG *stops = static_cast<GradientStopsCG*>(aPattern.mStops.get());
CGPoint startPoint = { aPattern.mBegin.x, aPattern.mBegin.y };
CGPoint endPoint = { aPattern.mEnd.x, aPattern.mEnd.y };
int repeatStartFactor = 0, repeatEndFactor = 1;
// if we don't have a line then we can't extend it
if (aPattern.mEnd.x != aPattern.mBegin.x ||
aPattern.mEnd.y != aPattern.mBegin.y) {
CalculateRepeatingGradientParams(&startPoint, &endPoint, aExtents,
&repeatStartFactor, &repeatEndFactor);
}
CGGradientRef gradient = CreateRepeatingGradient(aColorSpace, cg, stops, repeatStartFactor, repeatEndFactor, aReflect);
CGContextDrawLinearGradient(cg, gradient, startPoint, endPoint,
kCGGradientDrawsBeforeStartLocation | kCGGradientDrawsAfterEndLocation);
CGGradientRelease(gradient);
}
static CGPoint CGRectTopLeft(CGRect a)
{ return a.origin; }
static CGPoint CGRectBottomLeft(CGRect a)
{ return CGPointMake(a.origin.x, a.origin.y + a.size.height); }
static CGPoint CGRectTopRight(CGRect a)
{ return CGPointMake(a.origin.x + a.size.width, a.origin.y); }
static CGPoint CGRectBottomRight(CGRect a)
{ return CGPointMake(a.origin.x + a.size.width, a.origin.y + a.size.height); }
static CGFloat
CGPointDistance(CGPoint a, CGPoint b)
{
return hypot(a.x-b.x, a.y-b.y);
}
static void
DrawRadialRepeatingGradient(CGColorSpaceRef aColorSpace, CGContextRef cg,
const RadialGradientPattern &aPattern,
const CGRect &aExtents, bool aReflect)
{
GradientStopsCG *stops = static_cast<GradientStopsCG*>(aPattern.mStops.get());
CGPoint startCenter = { aPattern.mCenter1.x, aPattern.mCenter1.y };
CGFloat startRadius = aPattern.mRadius1;
CGPoint endCenter = { aPattern.mCenter2.x, aPattern.mCenter2.y };
CGFloat endRadius = aPattern.mRadius2;
// find the maximum distance from endCenter to a corner of aExtents
CGFloat minimumEndRadius = endRadius;
minimumEndRadius = max(minimumEndRadius, CGPointDistance(endCenter, CGRectTopLeft(aExtents)));
minimumEndRadius = max(minimumEndRadius, CGPointDistance(endCenter, CGRectBottomLeft(aExtents)));
minimumEndRadius = max(minimumEndRadius, CGPointDistance(endCenter, CGRectTopRight(aExtents)));
minimumEndRadius = max(minimumEndRadius, CGPointDistance(endCenter, CGRectBottomRight(aExtents)));
CGFloat length = endRadius - startRadius;
int repeatStartFactor = 0, repeatEndFactor = 1;
while (endRadius < minimumEndRadius) {
endRadius += length;
repeatEndFactor++;
}
while (startRadius-length >= 0) {
startRadius -= length;
repeatStartFactor--;
}
CGGradientRef gradient = CreateRepeatingGradient(aColorSpace, cg, stops, repeatStartFactor, repeatEndFactor, aReflect);
//XXX: are there degenerate radial gradients that we should avoid drawing?
CGContextDrawRadialGradient(cg, gradient, startCenter, startRadius, endCenter, endRadius,
kCGGradientDrawsBeforeStartLocation | kCGGradientDrawsAfterEndLocation);
CGGradientRelease(gradient);
}
static void
DrawGradient(CGColorSpaceRef aColorSpace,
CGContextRef cg, const Pattern &aPattern, const CGRect &aExtents)
{
if (MOZ2D_ERROR_IF(!cg)) {
return;
}
if (CGRectIsEmpty(aExtents)) {
return;
}
if (aPattern.GetType() == PatternType::LINEAR_GRADIENT) {
const LinearGradientPattern& pat = static_cast<const LinearGradientPattern&>(aPattern);
GradientStopsCG *stops = static_cast<GradientStopsCG*>(pat.mStops.get());
CGAffineTransform patternMatrix = GfxMatrixToCGAffineTransform(pat.mMatrix);
CGContextConcatCTM(cg, patternMatrix);
CGRect extents = CGRectApplyAffineTransform(aExtents, CGAffineTransformInvert(patternMatrix));
if (stops->mExtend == ExtendMode::CLAMP) {
// XXX: we should take the m out of the properties of LinearGradientPatterns
CGPoint startPoint = { pat.mBegin.x, pat.mBegin.y };
CGPoint endPoint = { pat.mEnd.x, pat.mEnd.y };
// Canvas spec states that we should avoid drawing degenerate gradients (XXX: should this be in common code?)
//if (startPoint.x == endPoint.x && startPoint.y == endPoint.y)
// return;
CGContextDrawLinearGradient(cg, stops->mGradient, startPoint, endPoint,
kCGGradientDrawsBeforeStartLocation | kCGGradientDrawsAfterEndLocation);
} else if (stops->mExtend == ExtendMode::REPEAT || stops->mExtend == ExtendMode::REFLECT) {
DrawLinearRepeatingGradient(aColorSpace, cg, pat, extents, stops->mExtend == ExtendMode::REFLECT);
}
} else if (aPattern.GetType() == PatternType::RADIAL_GRADIENT) {
const RadialGradientPattern& pat = static_cast<const RadialGradientPattern&>(aPattern);
CGAffineTransform patternMatrix = GfxMatrixToCGAffineTransform(pat.mMatrix);
CGContextConcatCTM(cg, patternMatrix);
CGRect extents = CGRectApplyAffineTransform(aExtents, CGAffineTransformInvert(patternMatrix));
GradientStopsCG *stops = static_cast<GradientStopsCG*>(pat.mStops.get());
if (stops->mExtend == ExtendMode::CLAMP) {
// XXX: we should take the m out of the properties of RadialGradientPatterns
CGPoint startCenter = { pat.mCenter1.x, pat.mCenter1.y };
CGFloat startRadius = pat.mRadius1;
CGPoint endCenter = { pat.mCenter2.x, pat.mCenter2.y };
CGFloat endRadius = pat.mRadius2;
//XXX: are there degenerate radial gradients that we should avoid drawing?
CGContextDrawRadialGradient(cg, stops->mGradient, startCenter, startRadius, endCenter, endRadius,
kCGGradientDrawsBeforeStartLocation | kCGGradientDrawsAfterEndLocation);
} else if (stops->mExtend == ExtendMode::REPEAT || stops->mExtend == ExtendMode::REFLECT) {
DrawRadialRepeatingGradient(aColorSpace, cg, pat, extents, stops->mExtend == ExtendMode::REFLECT);
}
} else {
assert(0);
}
}
static void
drawPattern(void *info, CGContextRef context)
{
CGImageRef image = static_cast<CGImageRef>(info);
CGRect rect = {{0, 0},
{static_cast<CGFloat>(CGImageGetWidth(image)),
static_cast<CGFloat>(CGImageGetHeight(image))}};
CGContextDrawImage(context, rect, image);
}
static void
releaseInfo(void *info)
{
CGImageRef image = static_cast<CGImageRef>(info);
CGImageRelease(image);
}
CGPatternCallbacks patternCallbacks = {
0,
drawPattern,
releaseInfo
};
static bool
isGradient(const Pattern &aPattern)
{
return aPattern.GetType() == PatternType::LINEAR_GRADIENT || aPattern.GetType() == PatternType::RADIAL_GRADIENT;
}
static bool
isNonRepeatingSurface(const Pattern& aPattern)
{
return aPattern.GetType() == PatternType::SURFACE &&
static_cast<const SurfacePattern&>(aPattern).mExtendMode != ExtendMode::REPEAT;
}
/* CoreGraphics patterns ignore the userspace transform so
* we need to multiply it in */
static CGPatternRef
CreateCGPattern(const Pattern &aPattern, CGAffineTransform aUserSpace)
{
const SurfacePattern& pat = static_cast<const SurfacePattern&>(aPattern);
// XXX: is .get correct here?
CGImageRef image = GetRetainedImageFromSourceSurface(pat.mSurface.get());
Matrix patTransform = pat.mMatrix;
if (!pat.mSamplingRect.IsEmpty()) {
CGImageRef temp = CGImageCreateWithImageInRect(image, RectToCGRect(pat.mSamplingRect));
CGImageRelease(image);
image = temp;
patTransform.PreTranslate(pat.mSamplingRect.x, pat.mSamplingRect.y);
}
CGFloat xStep, yStep;
switch (pat.mExtendMode) {
case ExtendMode::CLAMP:
// The 1 << 22 comes from Webkit see Pattern::createPlatformPattern() in PatternCG.cpp for more info
xStep = static_cast<CGFloat>(1 << 22);
yStep = static_cast<CGFloat>(1 << 22);
break;
case ExtendMode::REFLECT:
assert(0);
case ExtendMode::REPEAT:
xStep = static_cast<CGFloat>(CGImageGetWidth(image));
yStep = static_cast<CGFloat>(CGImageGetHeight(image));
// webkit uses wkCGPatternCreateWithImageAndTransform a wrapper around CGPatternCreateWithImage2
// this is done to avoid pixel-cracking along pattern boundaries
// (see https://bugs.webkit.org/show_bug.cgi?id=53055)
// typedef enum {
// wkPatternTilingNoDistortion,
// wkPatternTilingConstantSpacingMinimalDistortion,
// wkPatternTilingConstantSpacing
// } wkPatternTiling;
// extern CGPatternRef (*wkCGPatternCreateWithImageAndTransform)(CGImageRef, CGAffineTransform, int);
}
//XXX: We should be using CGContextDrawTiledImage when we can. Even though it
// creates a pattern, it seems to go down a faster path than using a delegate
// like we do below
CGRect bounds = {
{0, 0,},
{static_cast<CGFloat>(CGImageGetWidth(image)), static_cast<CGFloat>(CGImageGetHeight(image))}
};
CGAffineTransform transform =
CGAffineTransformConcat(CGAffineTransformConcat(CGAffineTransformMakeScale(1,
-1),
GfxMatrixToCGAffineTransform(patTransform)),
aUserSpace);
transform = CGAffineTransformTranslate(transform, 0, -static_cast<float>(CGImageGetHeight(image)));
return CGPatternCreate(image, bounds, transform, xStep, yStep, kCGPatternTilingConstantSpacing,
true, &patternCallbacks);
}
static void
SetFillFromPattern(CGContextRef cg, CGColorSpaceRef aColorSpace, const Pattern &aPattern)
{
if (MOZ2D_ERROR_IF(!cg)) {
return;
}
assert(!isGradient(aPattern));
if (aPattern.GetType() == PatternType::COLOR) {
const Color& color = static_cast<const ColorPattern&>(aPattern).mColor;
//XXX: we should cache colors
CGColorRef cgcolor = ColorToCGColor(aColorSpace, color);
CGContextSetFillColorWithColor(cg, cgcolor);
CGColorRelease(cgcolor);
} else if (aPattern.GetType() == PatternType::SURFACE) {
CGColorSpaceRef patternSpace;
patternSpace = CGColorSpaceCreatePattern (nullptr);
CGContextSetFillColorSpace(cg, patternSpace);
CGColorSpaceRelease(patternSpace);
CGPatternRef pattern = CreateCGPattern(aPattern, CGContextGetCTM(cg));
const SurfacePattern& pat = static_cast<const SurfacePattern&>(aPattern);
CGContextSetInterpolationQuality(cg, InterpolationQualityFromFilter(pat.mFilter));
CGFloat alpha = 1.;
CGContextSetFillPattern(cg, pattern, &alpha);
CGPatternRelease(pattern);
}
}
static void
SetStrokeFromPattern(CGContextRef cg, CGColorSpaceRef aColorSpace, const Pattern &aPattern)
{
assert(!isGradient(aPattern));
if (aPattern.GetType() == PatternType::COLOR) {
const Color& color = static_cast<const ColorPattern&>(aPattern).mColor;
//XXX: we should cache colors
CGColorRef cgcolor = ColorToCGColor(aColorSpace, color);
CGContextSetStrokeColorWithColor(cg, cgcolor);
CGColorRelease(cgcolor);
} else if (aPattern.GetType() == PatternType::SURFACE) {
CGColorSpaceRef patternSpace;
patternSpace = CGColorSpaceCreatePattern (nullptr);
CGContextSetStrokeColorSpace(cg, patternSpace);
CGColorSpaceRelease(patternSpace);
CGPatternRef pattern = CreateCGPattern(aPattern, CGContextGetCTM(cg));
const SurfacePattern& pat = static_cast<const SurfacePattern&>(aPattern);
CGContextSetInterpolationQuality(cg, InterpolationQualityFromFilter(pat.mFilter));
CGFloat alpha = 1.;
CGContextSetStrokePattern(cg, pattern, &alpha);
CGPatternRelease(pattern);
}
}
void
DrawTargetCG::MaskSurface(const Pattern &aSource,
SourceSurface *aMask,
Point aOffset,
const DrawOptions &aDrawOptions)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
MarkChanged();
CGContextSaveGState(mCg);
CGContextSetBlendMode(mCg, ToBlendMode(aDrawOptions.mCompositionOp));
UnboundnessFixer fixer;
CGContextRef cg = fixer.Check(mCg, aDrawOptions.mCompositionOp);
if (MOZ2D_ERROR_IF(!cg)) {
return;
}
CGContextSetAlpha(cg, aDrawOptions.mAlpha);
CGContextSetShouldAntialias(cg, aDrawOptions.mAntialiasMode != AntialiasMode::NONE);
CGContextConcatCTM(cg, GfxMatrixToCGAffineTransform(mTransform));
CGImageRef image = GetRetainedImageFromSourceSurface(aMask);
// use a negative-y so that the mask image draws right ways up
CGContextScaleCTM(cg, 1, -1);
IntSize size = aMask->GetSize();
CGContextClipToMask(cg, CGRectMake(aOffset.x, -(aOffset.y + size.height), size.width, size.height), image);
CGContextScaleCTM(cg, 1, -1);
if (isGradient(aSource)) {
// we shouldn't need to clip to an additional rectangle
// as the cliping to the mask should be sufficient.
DrawGradient(mColorSpace, cg, aSource, CGRectMake(aOffset.x, aOffset.y, size.width, size.height));
} else {
SetFillFromPattern(cg, mColorSpace, aSource);
CGContextFillRect(cg, CGRectMake(aOffset.x, aOffset.y, size.width, size.height));
}
CGImageRelease(image);
fixer.Fix(mCg);
CGContextRestoreGState(mCg);
}
void
DrawTargetCG::FillRect(const Rect &aRect,
const Pattern &aPattern,
const DrawOptions &aDrawOptions)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
MarkChanged();
CGContextSaveGState(mCg);
UnboundnessFixer fixer;
CGContextRef cg = fixer.Check(mCg, aDrawOptions.mCompositionOp, &aRect);
if (MOZ2D_ERROR_IF(!cg)) {
return;
}
CGContextSetAlpha(mCg, aDrawOptions.mAlpha);
CGContextSetShouldAntialias(cg, aDrawOptions.mAntialiasMode != AntialiasMode::NONE);
CGContextSetBlendMode(mCg, ToBlendMode(aDrawOptions.mCompositionOp));
CGContextConcatCTM(cg, GfxMatrixToCGAffineTransform(mTransform));
if (isGradient(aPattern)) {
CGContextClipToRect(cg, RectToCGRect(aRect));
CGRect clipBounds = CGContextGetClipBoundingBox(cg);
DrawGradient(mColorSpace, cg, aPattern, clipBounds);
} else if (isNonRepeatingSurface(aPattern)) {
// SetFillFromPattern can handle this case but using CGContextDrawImage
// should give us better performance, better output, smaller PDF and
// matches what cairo does.
const SurfacePattern& pat = static_cast<const SurfacePattern&>(aPattern);
CGImageRef image = GetRetainedImageFromSourceSurface(pat.mSurface.get());
Matrix transform = pat.mMatrix;
if (!pat.mSamplingRect.IsEmpty()) {
CGImageRef temp = CGImageCreateWithImageInRect(image, RectToCGRect(pat.mSamplingRect));
CGImageRelease(image);
image = temp;
transform.PreTranslate(pat.mSamplingRect.x, pat.mSamplingRect.y);
}
CGContextClipToRect(cg, RectToCGRect(aRect));
CGContextConcatCTM(cg, GfxMatrixToCGAffineTransform(transform));
CGContextTranslateCTM(cg, 0, CGImageGetHeight(image));
CGContextScaleCTM(cg, 1, -1);
CGRect imageRect = CGRectMake(0, 0, CGImageGetWidth(image), CGImageGetHeight(image));
CGContextSetInterpolationQuality(cg, InterpolationQualityFromFilter(pat.mFilter));
CGContextDrawImage(cg, imageRect, image);
CGImageRelease(image);
} else {
SetFillFromPattern(cg, mColorSpace, aPattern);
CGContextFillRect(cg, RectToCGRect(aRect));
}
fixer.Fix(mCg);
CGContextRestoreGState(mCg);
}
static Float
DashPeriodLength(const StrokeOptions& aStrokeOptions)
{
Float length = 0;
for (size_t i = 0; i < aStrokeOptions.mDashLength; i++) {
length += aStrokeOptions.mDashPattern[i];
}
if (aStrokeOptions.mDashLength & 1) {
// "If an odd number of values is provided, then the list of values is
// repeated to yield an even number of values."
// Double the length.
length += length;
}
return length;
}
inline Float
RoundDownToMultiple(Float aValue, Float aFactor)
{
return floorf(aValue / aFactor) * aFactor;
}
static Rect
UserSpaceStrokeClip(const Rect &aDeviceClip,
const Matrix &aTransform,
const StrokeOptions &aStrokeOptions)
{
Matrix inverse = aTransform;
if (!inverse.Invert()) {
return Rect();
}
Rect deviceClip = aDeviceClip;
deviceClip.Inflate(MaxStrokeExtents(aStrokeOptions, aTransform));
return inverse.TransformBounds(deviceClip);
}
static Rect
ShrinkClippedStrokedRect(const Rect &aStrokedRect, const Rect &aDeviceClip,
const Matrix &aTransform,
const StrokeOptions &aStrokeOptions)
{
Rect userSpaceStrokeClip =
UserSpaceStrokeClip(aDeviceClip, aTransform, aStrokeOptions);
Rect intersection = aStrokedRect.Intersect(userSpaceStrokeClip);
Float dashPeriodLength = DashPeriodLength(aStrokeOptions);
if (intersection.IsEmpty() || dashPeriodLength == 0.0f) {
return intersection;
}
// Reduce the rectangle side lengths in multiples of the dash period length
// so that the visible dashes stay in the same place.
Margin insetBy = aStrokedRect - intersection;
insetBy.top = RoundDownToMultiple(insetBy.top, dashPeriodLength);
insetBy.right = RoundDownToMultiple(insetBy.right, dashPeriodLength);
insetBy.bottom = RoundDownToMultiple(insetBy.bottom, dashPeriodLength);
insetBy.left = RoundDownToMultiple(insetBy.left, dashPeriodLength);
Rect shrunkRect = aStrokedRect;
shrunkRect.Deflate(insetBy);
return shrunkRect;
}
// Liang-Barsky
// This algorithm was chosen for its code brevity, with the hope that its
// performance is good enough.
// Sets aStart and aEnd to floats between 0 and the line length, or returns
// false if the line is completely outside the rect.
static bool
IntersectLineWithRect(const Point& aP1, const Point& aP2, const Rect& aClip,
Float* aStart, Float* aEnd)
{
Float t0 = 0.0f;
Float t1 = 1.0f;
Point vector = aP2 - aP1;
for (uint32_t edge = 0; edge < 4; edge++) {
Float p, q;
switch (edge) {
case 0: p = -vector.x; q = aP1.x - aClip.x; break;
case 1: p = vector.x; q = aClip.XMost() - aP1.x; break;
case 2: p = -vector.y; q = aP1.y - aClip.y; break;
case 3: p = vector.y; q = aClip.YMost() - aP1.y; break;
}
if (p == 0.0f) {
// Line is parallel to the edge.
if (q < 0.0f) {
return false;
}
continue;
}
Float r = q / p;
if (p < 0) {
t0 = std::max(t0, r);
} else {
t1 = std::min(t1, r);
}
if (t0 > t1) {
return false;
}
}
Float length = vector.Length();
*aStart = t0 * length;
*aEnd = t1 * length;
return true;
}
// Adjusts aP1 and aP2 to a shrunk line, or returns false if the line is
// completely outside the clip.
static bool
ShrinkClippedStrokedLine(Point &aP1, Point& aP2, const Rect &aDeviceClip,
const Matrix &aTransform,
const StrokeOptions &aStrokeOptions)
{
Rect userSpaceStrokeClip =
UserSpaceStrokeClip(aDeviceClip, aTransform, aStrokeOptions);
Point vector = aP2 - aP1;
Float length = vector.Length();
if (length == 0.0f) {
return true;
}
Float start = 0;
Float end = length;
if (!IntersectLineWithRect(aP1, aP2, userSpaceStrokeClip, &start, &end)) {
return false;
}
Float dashPeriodLength = DashPeriodLength(aStrokeOptions);
if (dashPeriodLength > 0.0f) {
// Shift the line points by multiples of dashPeriodLength so that the
// dashes stay in the same place.
start = RoundDownToMultiple(start, dashPeriodLength);
end = length - RoundDownToMultiple(length - end, dashPeriodLength);
}
Point startPoint = aP1;
aP1 = Point(startPoint.x + start * vector.x / length,
startPoint.y + start * vector.y / length);
aP2 = Point(startPoint.x + end * vector.x / length,
startPoint.y + end * vector.y / length);
return true;
}
void
DrawTargetCG::StrokeLine(const Point &aP1, const Point &aP2, const Pattern &aPattern, const StrokeOptions &aStrokeOptions, const DrawOptions &aDrawOptions)
{
if (!std::isfinite(aP1.x) ||
!std::isfinite(aP1.y) ||
!std::isfinite(aP2.x) ||
!std::isfinite(aP2.y)) {
return;
}
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
Point p1 = aP1;
Point p2 = aP2;
Rect deviceClip(0, 0, mSize.width, mSize.height);
if (!ShrinkClippedStrokedLine(p1, p2, deviceClip, mTransform, aStrokeOptions)) {
return;
}
MarkChanged();
CGContextSaveGState(mCg);
UnboundnessFixer fixer;
CGContextRef cg = fixer.Check(mCg, aDrawOptions.mCompositionOp);
if (MOZ2D_ERROR_IF(!cg)) {
return;
}
CGContextSetAlpha(mCg, aDrawOptions.mAlpha);
CGContextSetShouldAntialias(cg, aDrawOptions.mAntialiasMode != AntialiasMode::NONE);
CGContextSetBlendMode(mCg, ToBlendMode(aDrawOptions.mCompositionOp));
CGContextConcatCTM(cg, GfxMatrixToCGAffineTransform(mTransform));
CGContextBeginPath(cg);
CGContextMoveToPoint(cg, p1.x, p1.y);
CGContextAddLineToPoint(cg, p2.x, p2.y);
SetStrokeOptions(cg, aStrokeOptions);
if (isGradient(aPattern)) {
CGContextReplacePathWithStrokedPath(cg);
CGRect extents = CGContextGetPathBoundingBox(cg);
//XXX: should we use EO clip here?
CGContextClip(cg);
DrawGradient(mColorSpace, cg, aPattern, extents);
} else {
SetStrokeFromPattern(cg, mColorSpace, aPattern);
CGContextStrokePath(cg);
}
fixer.Fix(mCg);
CGContextRestoreGState(mCg);
}
static bool
IsInteger(Float aValue)
{
return floorf(aValue) == aValue;
}
static bool
IsPixelAlignedStroke(const Rect& aRect, Float aLineWidth)
{
Float halfWidth = aLineWidth/2;
return IsInteger(aLineWidth) &&
IsInteger(aRect.x - halfWidth) && IsInteger(aRect.y - halfWidth) &&
IsInteger(aRect.XMost() - halfWidth) && IsInteger(aRect.YMost() - halfWidth);
}
void
DrawTargetCG::StrokeRect(const Rect &aRect,
const Pattern &aPattern,
const StrokeOptions &aStrokeOptions,
const DrawOptions &aDrawOptions)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
if (!aRect.IsFinite()) {
return;
}
MarkChanged();
CGContextSaveGState(mCg);
UnboundnessFixer fixer;
CGContextRef cg = fixer.Check(mCg, aDrawOptions.mCompositionOp);
if (MOZ2D_ERROR_IF(!cg)) {
return;
}
// Stroking large rectangles with dashes is expensive with CG (fixed
// overhead based on the number of dashes, regardless of whether the dashes
// are visible), so we try to reduce the size of the stroked rectangle as
// much as possible before passing it on to CG.
Rect rect = aRect;
if (!rect.IsEmpty()) {
Rect deviceClip(0, 0, mSize.width, mSize.height);
rect = ShrinkClippedStrokedRect(rect, deviceClip, mTransform, aStrokeOptions);
if (rect.IsEmpty()) {
return;
}
}
CGContextSetAlpha(mCg, aDrawOptions.mAlpha);
CGContextSetBlendMode(mCg, ToBlendMode(aDrawOptions.mCompositionOp));
// Work around Quartz bug where antialiasing causes corner pixels to be off by
// 1 channel value (e.g. rgb(1,1,1) values appear at the corner of solid
// black stroke), by turning off antialiasing when the edges of the stroke
// are pixel-aligned. Note that when a transform's components are all
// integers, it maps integers coordinates to integer coordinates.
bool pixelAlignedStroke = mTransform.IsAllIntegers() &&
mTransform.PreservesAxisAlignedRectangles() &&
aPattern.GetType() == PatternType::COLOR &&
IsPixelAlignedStroke(rect, aStrokeOptions.mLineWidth);
CGContextSetShouldAntialias(cg,
aDrawOptions.mAntialiasMode != AntialiasMode::NONE && !pixelAlignedStroke);
CGContextConcatCTM(cg, GfxMatrixToCGAffineTransform(mTransform));
SetStrokeOptions(cg, aStrokeOptions);
if (isGradient(aPattern)) {
// There's no CGContextClipStrokeRect so we do it by hand
CGContextBeginPath(cg);
CGContextAddRect(cg, RectToCGRect(rect));
CGContextReplacePathWithStrokedPath(cg);
CGRect extents = CGContextGetPathBoundingBox(cg);
//XXX: should we use EO clip here?
CGContextClip(cg);
DrawGradient(mColorSpace, cg, aPattern, extents);
} else {
SetStrokeFromPattern(cg, mColorSpace, aPattern);
// We'd like to use CGContextStrokeRect(cg, RectToCGRect(rect));
// Unfortunately, newer versions of OS X no longer start at the top-left
// corner and stroke clockwise as older OS X versions and all the other
// Moz2D backends do. (Newer versions start at the top right-hand corner
// and stroke counter-clockwise.) For consistency we draw the rect by hand.
CGContextBeginPath(cg);
CGContextMoveToPoint(cg, rect.x, rect.y);
CGContextAddLineToPoint(cg, rect.XMost(), rect.y);
CGContextAddLineToPoint(cg, rect.XMost(), rect.YMost());
CGContextAddLineToPoint(cg, rect.x, rect.YMost());
CGContextClosePath(cg);
CGContextStrokePath(cg);
}
fixer.Fix(mCg);
CGContextRestoreGState(mCg);
}
void
DrawTargetCG::ClearRect(const Rect &aRect)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
MarkChanged();
CGContextSaveGState(mCg);
CGContextConcatCTM(mCg, GfxMatrixToCGAffineTransform(mTransform));
CGContextClearRect(mCg, RectToCGRect(aRect));
CGContextRestoreGState(mCg);
}
void
DrawTargetCG::Stroke(const Path *aPath, const Pattern &aPattern, const StrokeOptions &aStrokeOptions, const DrawOptions &aDrawOptions)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
if (!aPath->GetBounds().IsFinite()) {
return;
}
MarkChanged();
CGContextSaveGState(mCg);
UnboundnessFixer fixer;
CGContextRef cg = fixer.Check(mCg, aDrawOptions.mCompositionOp);
if (MOZ2D_ERROR_IF(!cg)) {
return;
}
CGContextSetAlpha(mCg, aDrawOptions.mAlpha);
CGContextSetShouldAntialias(cg, aDrawOptions.mAntialiasMode != AntialiasMode::NONE);
CGContextSetBlendMode(mCg, ToBlendMode(aDrawOptions.mCompositionOp));
CGContextConcatCTM(cg, GfxMatrixToCGAffineTransform(mTransform));
CGContextBeginPath(cg);
assert(aPath->GetBackendType() == BackendType::COREGRAPHICS);
const PathCG *cgPath = static_cast<const PathCG*>(aPath);
CGContextAddPath(cg, cgPath->GetPath());
SetStrokeOptions(cg, aStrokeOptions);
if (isGradient(aPattern)) {
CGContextReplacePathWithStrokedPath(cg);
CGRect extents = CGContextGetPathBoundingBox(cg);
//XXX: should we use EO clip here?
CGContextClip(cg);
DrawGradient(mColorSpace, cg, aPattern, extents);
} else {
// XXX: we could put fill mode into the path fill rule if we wanted
SetStrokeFromPattern(cg, mColorSpace, aPattern);
CGContextStrokePath(cg);
}
fixer.Fix(mCg);
CGContextRestoreGState(mCg);
}
void
DrawTargetCG::Fill(const Path *aPath, const Pattern &aPattern, const DrawOptions &aDrawOptions)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
MarkChanged();
assert(aPath->GetBackendType() == BackendType::COREGRAPHICS);
CGContextSaveGState(mCg);
CGContextSetBlendMode(mCg, ToBlendMode(aDrawOptions.mCompositionOp));
UnboundnessFixer fixer;
CGContextRef cg = fixer.Check(mCg, aDrawOptions.mCompositionOp);
if (MOZ2D_ERROR_IF(!cg)) {
return;
}
CGContextSetAlpha(cg, aDrawOptions.mAlpha);
CGContextSetShouldAntialias(cg, aDrawOptions.mAntialiasMode != AntialiasMode::NONE);
CGContextConcatCTM(cg, GfxMatrixToCGAffineTransform(mTransform));
CGContextBeginPath(cg);
// XXX: we could put fill mode into the path fill rule if we wanted
const PathCG *cgPath = static_cast<const PathCG*>(aPath);
if (isGradient(aPattern)) {
// setup a clip to draw the gradient through
CGRect extents;
if (CGPathIsEmpty(cgPath->GetPath())) {
// Adding an empty path will cause us not to clip
// so clip everything explicitly
CGContextClipToRect(mCg, CGRectZero);
extents = CGRectZero;
} else {
CGContextAddPath(cg, cgPath->GetPath());
extents = CGContextGetPathBoundingBox(cg);
if (cgPath->GetFillRule() == FillRule::FILL_EVEN_ODD)
CGContextEOClip(mCg);
else
CGContextClip(mCg);
}
DrawGradient(mColorSpace, cg, aPattern, extents);
} else {
CGContextAddPath(cg, cgPath->GetPath());
SetFillFromPattern(cg, mColorSpace, aPattern);
if (cgPath->GetFillRule() == FillRule::FILL_EVEN_ODD)
CGContextEOFillPath(cg);
else
CGContextFillPath(cg);
}
fixer.Fix(mCg);
CGContextRestoreGState(mCg);
}
CGRect ComputeGlyphsExtents(CGRect *bboxes, CGPoint *positions, CFIndex count, float scale)
{
CGFloat x1, x2, y1, y2;
if (count < 1)
return CGRectZero;
x1 = bboxes[0].origin.x + positions[0].x;
x2 = bboxes[0].origin.x + positions[0].x + scale*bboxes[0].size.width;
y1 = bboxes[0].origin.y + positions[0].y;
y2 = bboxes[0].origin.y + positions[0].y + scale*bboxes[0].size.height;
// accumulate max and minimum coordinates
for (int i = 1; i < count; i++) {
x1 = min(x1, bboxes[i].origin.x + positions[i].x);
y1 = min(y1, bboxes[i].origin.y + positions[i].y);
x2 = max(x2, bboxes[i].origin.x + positions[i].x + scale*bboxes[i].size.width);
y2 = max(y2, bboxes[i].origin.y + positions[i].y + scale*bboxes[i].size.height);
}
CGRect extents = {{x1, y1}, {x2-x1, y2-y1}};
return extents;
}
typedef void (*CGContextSetFontSmoothingBackgroundColorFunc) (CGContextRef cgContext, CGColorRef color);
static CGContextSetFontSmoothingBackgroundColorFunc
GetCGContextSetFontSmoothingBackgroundColorFunc()
{
static CGContextSetFontSmoothingBackgroundColorFunc func = nullptr;
static bool lookedUpFunc = false;
if (!lookedUpFunc) {
func = (CGContextSetFontSmoothingBackgroundColorFunc)dlsym(
RTLD_DEFAULT, "CGContextSetFontSmoothingBackgroundColor");
lookedUpFunc = true;
}
return func;
}
void
DrawTargetCG::FillGlyphs(ScaledFont *aFont, const GlyphBuffer &aBuffer, const Pattern &aPattern, const DrawOptions &aDrawOptions,
const GlyphRenderingOptions *aGlyphRenderingOptions)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
MarkChanged();
assert(aBuffer.mNumGlyphs);
CGContextSaveGState(mCg);
if (aGlyphRenderingOptions && aGlyphRenderingOptions->GetType() == FontType::MAC) {
Color fontSmoothingBackgroundColor =
static_cast<const GlyphRenderingOptionsCG*>(aGlyphRenderingOptions)->FontSmoothingBackgroundColor();
if (fontSmoothingBackgroundColor.a > 0) {
CGContextSetFontSmoothingBackgroundColorFunc setFontSmoothingBGColorFunc =
GetCGContextSetFontSmoothingBackgroundColorFunc();
if (setFontSmoothingBGColorFunc) {
CGColorRef color = ColorToCGColor(mColorSpace, fontSmoothingBackgroundColor);
setFontSmoothingBGColorFunc(mCg, color);
CGColorRelease(color);
// Font rendering with a non-transparent font smoothing background color
// can leave pixels in our buffer where the rgb components exceed the alpha
// component. When this happens we need to clean up the data afterwards.
// The purpose of this is probably the following: Correct compositing of
// subpixel anti-aliased fonts on transparent backgrounds requires
// different alpha values per RGB component. Usually, premultiplied color
// values are derived by multiplying all components with the same per-pixel
// alpha value. However, if you multiply each component with a *different*
// alpha, and set the alpha component of the pixel to, say, the average
// of the alpha values that you used during the premultiplication of the
// RGB components, you can trick OVER compositing into doing a simplified
// form of component alpha compositing. (You just need to make sure to
// clamp the components of the result pixel to [0,255] afterwards.)
mMayContainInvalidPremultipliedData = true;
}
}
}
CGContextSetBlendMode(mCg, ToBlendMode(aDrawOptions.mCompositionOp));
UnboundnessFixer fixer;
CGContextRef cg = fixer.Check(mCg, aDrawOptions.mCompositionOp);
if (MOZ2D_ERROR_IF(!cg)) {
return;
}
CGContextSetAlpha(cg, aDrawOptions.mAlpha);
CGContextSetShouldAntialias(cg, aDrawOptions.mAntialiasMode != AntialiasMode::NONE);
if (aDrawOptions.mAntialiasMode != AntialiasMode::DEFAULT) {
CGContextSetShouldSmoothFonts(cg, aDrawOptions.mAntialiasMode == AntialiasMode::SUBPIXEL);
}
CGContextConcatCTM(cg, GfxMatrixToCGAffineTransform(mTransform));
ScaledFontMac* macFont = static_cast<ScaledFontMac*>(aFont);
// This code can execute millions of times in short periods, so we want to
// avoid heap allocation whenever possible. So we use an inline vector
// capacity of 64 elements, which is enough to typically avoid heap
// allocation in ~99% of cases.
Vector<CGGlyph, 64> glyphs;
Vector<CGPoint, 64> positions;
if (!glyphs.resizeUninitialized(aBuffer.mNumGlyphs) ||
!positions.resizeUninitialized(aBuffer.mNumGlyphs)) {
MOZ_CRASH("glyphs/positions allocation failed");
}
// Handle the flip
CGContextScaleCTM(cg, 1, -1);
// CGContextSetTextMatrix works differently with kCGTextClip && kCGTextFill
// It seems that it transforms the positions with TextFill and not with TextClip
// Therefore we'll avoid it. See also:
// http://cgit.freedesktop.org/cairo/commit/?id=9c0d761bfcdd28d52c83d74f46dd3c709ae0fa69
for (unsigned int i = 0; i < aBuffer.mNumGlyphs; i++) {
glyphs[i] = aBuffer.mGlyphs[i].mIndex;
// XXX: CGPointMake might not be inlined
positions[i] = CGPointMake(aBuffer.mGlyphs[i].mPosition.x,
-aBuffer.mGlyphs[i].mPosition.y);
}
//XXX: CGContextShowGlyphsAtPositions is 10.5+ for older versions use CGContextShowGlyphsWithAdvances
if (isGradient(aPattern)) {
CGContextSetTextDrawingMode(cg, kCGTextClip);
CGRect extents;
if (ScaledFontMac::CTFontDrawGlyphsPtr != nullptr) {
CGRect *bboxes = new CGRect[aBuffer.mNumGlyphs];
CTFontGetBoundingRectsForGlyphs(macFont->mCTFont, kCTFontDefaultOrientation,
glyphs.begin(), bboxes, aBuffer.mNumGlyphs);
extents = ComputeGlyphsExtents(bboxes, positions.begin(), aBuffer.mNumGlyphs, 1.0f);
ScaledFontMac::CTFontDrawGlyphsPtr(macFont->mCTFont, glyphs.begin(),
positions.begin(), aBuffer.mNumGlyphs, cg);
delete[] bboxes;
} else {
CGRect *bboxes = new CGRect[aBuffer.mNumGlyphs];
CGFontGetGlyphBBoxes(macFont->mFont, glyphs.begin(), aBuffer.mNumGlyphs, bboxes);
extents = ComputeGlyphsExtents(bboxes, positions.begin(), aBuffer.mNumGlyphs, macFont->mSize);
CGContextSetFont(cg, macFont->mFont);
CGContextSetFontSize(cg, macFont->mSize);
CGContextShowGlyphsAtPositions(cg, glyphs.begin(), positions.begin(),
aBuffer.mNumGlyphs);
delete[] bboxes;
}
CGContextScaleCTM(cg, 1, -1);
DrawGradient(mColorSpace, cg, aPattern, extents);
} else {
//XXX: with CoreGraphics we can stroke text directly instead of going
// through GetPath. It would be nice to add support for using that
CGContextSetTextDrawingMode(cg, kCGTextFill);
SetFillFromPattern(cg, mColorSpace, aPattern);
if (ScaledFontMac::CTFontDrawGlyphsPtr != nullptr) {
ScaledFontMac::CTFontDrawGlyphsPtr(macFont->mCTFont, glyphs.begin(),
positions.begin(),
aBuffer.mNumGlyphs, cg);
} else {
CGContextSetFont(cg, macFont->mFont);
CGContextSetFontSize(cg, macFont->mSize);
CGContextShowGlyphsAtPositions(cg, glyphs.begin(), positions.begin(),
aBuffer.mNumGlyphs);
}
}
fixer.Fix(mCg);
CGContextRestoreGState(cg);
}
extern "C" {
void
CGContextResetClip(CGContextRef);
};
void
DrawTargetCG::CopySurface(SourceSurface *aSurface,
const IntRect& aSourceRect,
const IntPoint &aDestination)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
MarkChanged();
if (aSurface->GetType() == SurfaceType::COREGRAPHICS_IMAGE ||
aSurface->GetType() == SurfaceType::COREGRAPHICS_CGCONTEXT ||
aSurface->GetType() == SurfaceType::DATA) {
CGImageRef image = GetRetainedImageFromSourceSurface(aSurface);
// XXX: it might be more efficient for us to do the copy directly if we have access to the bits
CGContextSaveGState(mCg);
// CopySurface ignores the clip, so we need to use private API to temporarily reset it
CGContextResetClip(mCg);
CGRect destRect = CGRectMake(aDestination.x, aDestination.y,
aSourceRect.width, aSourceRect.height);
CGContextClipToRect(mCg, destRect);
CGContextSetBlendMode(mCg, kCGBlendModeCopy);
CGContextScaleCTM(mCg, 1, -1);
CGRect flippedRect = CGRectMake(aDestination.x - aSourceRect.x, -(aDestination.y - aSourceRect.y + double(CGImageGetHeight(image))),
CGImageGetWidth(image), CGImageGetHeight(image));
// Quartz seems to copy A8 surfaces incorrectly if we don't initialize them
// to transparent first.
if (mFormat == SurfaceFormat::A8) {
CGContextClearRect(mCg, flippedRect);
}
CGContextDrawImage(mCg, flippedRect, image);
CGContextRestoreGState(mCg);
CGImageRelease(image);
}
}
void
DrawTargetCG::DrawSurfaceWithShadow(SourceSurface *aSurface, const Point &aDest, const Color &aColor, const Point &aOffset, Float aSigma, CompositionOp aOperator)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
MarkChanged();
CGImageRef image = GetRetainedImageFromSourceSurface(aSurface);
IntSize size = aSurface->GetSize();
CGContextSaveGState(mCg);
//XXX do we need to do the fixup here?
CGContextSetBlendMode(mCg, ToBlendMode(aOperator));
CGContextScaleCTM(mCg, 1, -1);
CGRect flippedRect = CGRectMake(aDest.x, -(aDest.y + size.height),
size.width, size.height);
CGColorRef color = ColorToCGColor(mColorSpace, aColor);
CGSize offset = {aOffset.x, -aOffset.y};
// CoreGraphics needs twice sigma as it's amount of blur
CGContextSetShadowWithColor(mCg, offset, 2*aSigma, color);
CGColorRelease(color);
CGContextDrawImage(mCg, flippedRect, image);
CGImageRelease(image);
CGContextRestoreGState(mCg);
}
bool
DrawTargetCG::Init(BackendType aType,
unsigned char* aData,
const IntSize &aSize,
int32_t aStride,
SurfaceFormat aFormat)
{
// XXX: we should come up with some consistent semantics for dealing
// with zero area drawtargets
if (aSize.width <= 0 ||
aSize.height <= 0 ||
size_t(aSize.width) > GetMaxSurfaceSize() ||
size_t(aSize.height) > GetMaxSurfaceSize())
{
gfxWarning() << "Failed to Init() DrawTargetCG because of bad size.";
mColorSpace = nullptr;
mCg = nullptr;
return false;
}
//XXX: handle SurfaceFormat
//XXX: we'd be better off reusing the Colorspace across draw targets
mColorSpace = CGColorSpaceCreateDeviceRGB();
if (aData == nullptr && aType != BackendType::COREGRAPHICS_ACCELERATED) {
// XXX: Currently, Init implicitly clears, that can often be a waste of time
size_t bufLen = BufferSizeFromStrideAndHeight(aStride, aSize.height);
if (bufLen == 0) {
mColorSpace = nullptr;
mCg = nullptr;
return false;
}
static_assert(sizeof(decltype(mData[0])) == 1,
"mData.Realloc() takes an object count, so its objects must be 1-byte sized if we use bufLen");
mData.Realloc(/* actually an object count */ bufLen, true);
aData = static_cast<unsigned char*>(mData);
}
mSize = aSize;
if (aType == BackendType::COREGRAPHICS_ACCELERATED) {
RefPtr<MacIOSurface> ioSurface = MacIOSurface::CreateIOSurface(aSize.width, aSize.height);
mCg = ioSurface->CreateIOSurfaceContext();
// If we don't have the symbol for 'CreateIOSurfaceContext' mCg will be null
// and we will fallback to software below
}
mFormat = SurfaceFormat::B8G8R8A8;
if (!mCg || aType == BackendType::COREGRAPHICS) {
int bitsPerComponent = 8;
CGBitmapInfo bitinfo;
if (aFormat == SurfaceFormat::A8) {
if (mColorSpace)
CGColorSpaceRelease(mColorSpace);
mColorSpace = nullptr;
bitinfo = kCGImageAlphaOnly;
mFormat = SurfaceFormat::A8;
} else {
bitinfo = kCGBitmapByteOrder32Host;
if (aFormat == SurfaceFormat::B8G8R8X8) {
bitinfo |= kCGImageAlphaNoneSkipFirst;
mFormat = aFormat;
} else {
bitinfo |= kCGImageAlphaPremultipliedFirst;
}
}
// XXX: what should we do if this fails?
mCg = CGBitmapContextCreate (aData,
mSize.width,
mSize.height,
bitsPerComponent,
aStride,
mColorSpace,
bitinfo);
}
assert(mCg);
if (!mCg) {
gfxCriticalError() << "Failed to create CG context";
return false;
}
// CGContext's default to have the origin at the bottom left
// so flip it to the top left
CGContextTranslateCTM(mCg, 0, mSize.height);
CGContextScaleCTM(mCg, 1, -1);
// See Bug 722164 for performance details
// Medium or higher quality lead to expensive interpolation
// for canvas we want to use low quality interpolation
// to have competitive performance with other canvas
// implementation.
// XXX: Create input parameter to control interpolation and
// use the default for content.
CGContextSetInterpolationQuality(mCg, kCGInterpolationLow);
if (aType == BackendType::COREGRAPHICS_ACCELERATED) {
// The bitmap backend uses callac to clear, we can't do that without
// reading back the surface. This should trigger something equivilent
// to glClear.
ClearRect(Rect(0, 0, mSize.width, mSize.height));
}
return true;
}
static void
EnsureValidPremultipliedData(CGContextRef aContext)
{
if (CGBitmapContextGetBitsPerPixel(aContext) != 32 ||
CGBitmapContextGetAlphaInfo(aContext) != kCGImageAlphaPremultipliedFirst) {
return;
}
uint8_t* bitmapData = (uint8_t*)CGBitmapContextGetData(aContext);
int w = CGBitmapContextGetWidth(aContext);
int h = CGBitmapContextGetHeight(aContext);
int stride = CGBitmapContextGetBytesPerRow(aContext);
for (int y = 0; y < h; y++) {
for (int x = 0; x < w; x++) {
int i = y * stride + x * 4;
uint8_t a = bitmapData[i + 3];
// Clamp rgb components to the alpha component.
if (bitmapData[i + 0] > a) {
bitmapData[i + 0] = a;
}
if (bitmapData[i + 1] > a) {
bitmapData[i + 1] = a;
}
if (bitmapData[i + 2] > a) {
bitmapData[i + 2] = a;
}
}
}
}
void
DrawTargetCG::Flush()
{
if (GetContextType(mCg) == CG_CONTEXT_TYPE_IOSURFACE) {
CGContextFlush(mCg);
} else if (GetContextType(mCg) == CG_CONTEXT_TYPE_BITMAP &&
mMayContainInvalidPremultipliedData) {
// We can't guarantee that all our users can handle pixel data where an RGB
// component value exceeds the pixel's alpha value. In particular, the
// color conversion that CG does when we draw a CGImage snapshot of this
// context into a context that has a different color space throws up on
// invalid premultiplied data and creates completely wrong colors.
// Sanitizing the data means that we lose some of the fake component alpha
// behavior that font rendering tries to give us, but the result still
// looks good enough to prefer it over grayscale font anti-aliasing.
EnsureValidPremultipliedData(mCg);
mMayContainInvalidPremultipliedData = false;
}
}
bool
DrawTargetCG::Init(CGContextRef cgContext, const IntSize &aSize)
{
// XXX: we should come up with some consistent semantics for dealing
// with zero area drawtargets
if (aSize.width == 0 || aSize.height == 0) {
mColorSpace = nullptr;
mCg = nullptr;
return false;
}
//XXX: handle SurfaceFormat
//XXX: we'd be better off reusing the Colorspace across draw targets
mColorSpace = CGColorSpaceCreateDeviceRGB();
mSize = aSize;
mCg = cgContext;
CGContextRetain(mCg);
assert(mCg);
if (!mCg) {
gfxCriticalError() << "Invalid CG context at Init";
return false;
}
// CGContext's default to have the origin at the bottom left.
// However, currently the only use of this function is to construct a
// DrawTargetCG around a CGContextRef from a cairo quartz surface which
// already has it's origin adjusted.
//
// CGContextTranslateCTM(mCg, 0, mSize.height);
// CGContextScaleCTM(mCg, 1, -1);
mFormat = SurfaceFormat::B8G8R8A8;
if (GetContextType(mCg) == CG_CONTEXT_TYPE_BITMAP) {
CGColorSpaceRef colorspace;
CGBitmapInfo bitinfo = CGBitmapContextGetBitmapInfo(mCg);
colorspace = CGBitmapContextGetColorSpace (mCg);
if (CGColorSpaceGetNumberOfComponents(colorspace) == 1) {
mFormat = SurfaceFormat::A8;
} else if ((bitinfo & kCGBitmapAlphaInfoMask) == kCGImageAlphaNoneSkipFirst) {
mFormat = SurfaceFormat::B8G8R8X8;
}
}
return true;
}
bool
DrawTargetCG::Init(BackendType aType, const IntSize &aSize, SurfaceFormat &aFormat)
{
int32_t stride = GetAlignedStride<16>(aSize.width * BytesPerPixel(aFormat));
// Calling Init with aData == nullptr will allocate.
return Init(aType, nullptr, aSize, stride, aFormat);
}
TemporaryRef<PathBuilder>
DrawTargetCG::CreatePathBuilder(FillRule aFillRule) const
{
return new PathBuilderCG(aFillRule);
}
void*
DrawTargetCG::GetNativeSurface(NativeSurfaceType aType)
{
if ((aType == NativeSurfaceType::CGCONTEXT && GetContextType(mCg) == CG_CONTEXT_TYPE_BITMAP) ||
(aType == NativeSurfaceType::CGCONTEXT_ACCELERATED && GetContextType(mCg) == CG_CONTEXT_TYPE_IOSURFACE)) {
return mCg;
} else {
return nullptr;
}
}
void
DrawTargetCG::Mask(const Pattern &aSource,
const Pattern &aMask,
const DrawOptions &aDrawOptions)
{
MarkChanged();
CGContextSaveGState(mCg);
if (isGradient(aMask)) {
assert(0);
} else {
if (aMask.GetType() == PatternType::COLOR) {
DrawOptions drawOptions(aDrawOptions);
const Color& color = static_cast<const ColorPattern&>(aMask).mColor;
drawOptions.mAlpha *= color.a;
assert(0);
// XXX: we need to get a rect that when transformed covers the entire surface
//Rect
//FillRect(rect, aSource, drawOptions);
} else if (aMask.GetType() == PatternType::SURFACE) {
const SurfacePattern& pat = static_cast<const SurfacePattern&>(aMask);
CGImageRef mask = GetRetainedImageFromSourceSurface(pat.mSurface.get());
MOZ_ASSERT(pat.mSamplingRect.IsEmpty(), "Sampling rect not supported with masks!");
Rect rect(0,0, CGImageGetWidth(mask), CGImageGetHeight(mask));
// XXX: probably we need to do some flipping of the image or something
CGContextClipToMask(mCg, RectToCGRect(rect), mask);
FillRect(rect, aSource, aDrawOptions);
CGImageRelease(mask);
}
}
CGContextRestoreGState(mCg);
}
void
DrawTargetCG::PushClipRect(const Rect &aRect)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
CGContextSaveGState(mCg);
/* We go through a bit of trouble to temporarilly set the transform
* while we add the path */
CGAffineTransform previousTransform = CGContextGetCTM(mCg);
CGContextConcatCTM(mCg, GfxMatrixToCGAffineTransform(mTransform));
CGContextClipToRect(mCg, RectToCGRect(aRect));
CGContextSetCTM(mCg, previousTransform);
}
void
DrawTargetCG::PushClip(const Path *aPath)
{
if (MOZ2D_ERROR_IF(!mCg)) {
return;
}
CGContextSaveGState(mCg);
CGContextBeginPath(mCg);
assert(aPath->GetBackendType() == BackendType::COREGRAPHICS);
const PathCG *cgPath = static_cast<const PathCG*>(aPath);
// Weirdly, CoreGraphics clips empty paths as all shown
// but emtpy rects as all clipped. We detect this situation and
// workaround it appropriately
if (CGPathIsEmpty(cgPath->GetPath())) {
// XXX: should we return here?
CGContextClipToRect(mCg, CGRectZero);
}
/* We go through a bit of trouble to temporarilly set the transform
* while we add the path. XXX: this could be improved if we keep
* the CTM as resident state on the DrawTarget. */
CGContextSaveGState(mCg);
CGContextConcatCTM(mCg, GfxMatrixToCGAffineTransform(mTransform));
CGContextAddPath(mCg, cgPath->GetPath());
CGContextRestoreGState(mCg);
if (cgPath->GetFillRule() == FillRule::FILL_EVEN_ODD)
CGContextEOClip(mCg);
else
CGContextClip(mCg);
}
void
DrawTargetCG::PopClip()
{
CGContextRestoreGState(mCg);
}
void
DrawTargetCG::MarkChanged()
{
if (mSnapshot) {
if (mSnapshot->refCount() > 1) {
// We only need to worry about snapshots that someone else knows about
mSnapshot->DrawTargetWillChange();
}
mSnapshot = nullptr;
}
}
CGContextRef
BorrowedCGContext::BorrowCGContextFromDrawTarget(DrawTarget *aDT)
{
if ((aDT->GetBackendType() == BackendType::COREGRAPHICS ||
aDT->GetBackendType() == BackendType::COREGRAPHICS_ACCELERATED) &&
!aDT->IsTiledDrawTarget() && !aDT->IsDualDrawTarget()) {
DrawTargetCG* cgDT = static_cast<DrawTargetCG*>(aDT);
cgDT->Flush();
cgDT->MarkChanged();
// swap out the context
CGContextRef cg = cgDT->mCg;
if (MOZ2D_ERROR_IF(!cg)) {
return nullptr;
}
cgDT->mCg = nullptr;
// save the state to make it easier for callers to avoid mucking with things
CGContextSaveGState(cg);
CGContextConcatCTM(cg, GfxMatrixToCGAffineTransform(cgDT->mTransform));
return cg;
}
return nullptr;
}
void
BorrowedCGContext::ReturnCGContextToDrawTarget(DrawTarget *aDT, CGContextRef cg)
{
DrawTargetCG* cgDT = static_cast<DrawTargetCG*>(aDT);
CGContextRestoreGState(cg);
cgDT->mCg = cg;
}
}
}
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