gecko/gfx/thebes/gfxQuartzNativeDrawing.cpp
Jeff Muizelaar 557b4f19f9 Bug 895007. Handle zero size native drawing more gracefully. r=mattwoodrow
This fixes null drawtarget crashes

--HG--
extra : rebase_source : e7edd25c21edc636fad1a88940d97db4af269f0b
2013-07-17 16:16:41 -04:00

169 lines
6.1 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 "nsMathUtils.h"
#include "gfxQuartzNativeDrawing.h"
#include "gfxQuartzSurface.h"
#include "cairo-quartz.h"
#include "mozilla/gfx/2D.h"
// see cairo-quartz-surface.c for the complete list of these
enum {
kPrivateCGCompositeSourceOver = 2
};
using namespace mozilla::gfx;
using namespace mozilla;
// private Quartz routine needed here
extern "C" {
CG_EXTERN void CGContextSetCompositeOperation(CGContextRef, int);
}
gfxQuartzNativeDrawing::gfxQuartzNativeDrawing(gfxContext* ctx,
const gfxRect& nativeRect,
gfxFloat aBackingScale)
: mContext(ctx)
, mNativeRect(nativeRect)
, mBackingScale(aBackingScale)
{
mNativeRect.RoundOut();
}
CGContextRef
gfxQuartzNativeDrawing::BeginNativeDrawing()
{
NS_ASSERTION(!mQuartzSurface, "BeginNativeDrawing called when drawing already in progress");
if (!mContext->IsCairo()) {
DrawTarget *dt = mContext->GetDrawTarget();
if (mContext->GetDrawTarget()->IsDualDrawTarget()) {
IntSize backingSize(NSToIntFloor(mNativeRect.width * mBackingScale),
NSToIntFloor(mNativeRect.height * mBackingScale));
if (backingSize.IsEmpty())
return nullptr;
mDrawTarget = Factory::CreateDrawTarget(BACKEND_COREGRAPHICS, backingSize, FORMAT_B8G8R8A8);
Matrix transform;
transform.Scale(mBackingScale, mBackingScale);
transform.Translate(-mNativeRect.x, -mNativeRect.y);
mDrawTarget->SetTransform(transform);
dt = mDrawTarget;
}
mCGContext = mBorrowedContext.Init(dt);
MOZ_ASSERT(mCGContext);
return mCGContext;
}
gfxPoint deviceOffset;
nsRefPtr<gfxASurface> surf = mContext->CurrentSurface(&deviceOffset.x, &deviceOffset.y);
if (!surf || surf->CairoStatus())
return nullptr;
// if this is a native Quartz surface, we don't have to redirect
// rendering to our own CGContextRef; in most cases, we are able to
// use the CGContextRef from the surface directly. we can extend
// this to support offscreen drawing fairly easily in the future.
if (surf->GetType() == gfxASurface::SurfaceTypeQuartz &&
(surf->GetContentType() == gfxASurface::CONTENT_COLOR ||
(surf->GetContentType() == gfxASurface::CONTENT_COLOR_ALPHA))) {
mQuartzSurface = static_cast<gfxQuartzSurface*>(surf.get());
mSurfaceContext = mContext;
// grab the CGContextRef
mCGContext = cairo_quartz_get_cg_context_with_clip(mSurfaceContext->GetCairo());
if (!mCGContext)
return nullptr;
gfxMatrix m = mContext->CurrentMatrix();
CGContextTranslateCTM(mCGContext, deviceOffset.x, deviceOffset.y);
// I -think- that this context will always have an identity
// transform (since we don't maintain a transform on it in
// cairo-land, and instead push/pop as needed)
gfxFloat x0 = m.x0;
gfxFloat y0 = m.y0;
// We round x0/y0 if we don't have a scale, because otherwise things get
// rendered badly
// XXX how should we be rounding x0/y0?
if (!m.HasNonTranslationOrFlip()) {
x0 = floor(x0 + 0.5);
y0 = floor(y0 + 0.5);
}
CGContextConcatCTM(mCGContext, CGAffineTransformMake(m.xx, m.yx,
m.xy, m.yy,
x0, y0));
// bug 382049 - need to explicity set the composite operation to sourceOver
CGContextSetCompositeOperation(mCGContext, kPrivateCGCompositeSourceOver);
} else {
nsIntSize backingSize(NSToIntFloor(mNativeRect.width * mBackingScale),
NSToIntFloor(mNativeRect.height * mBackingScale));
mQuartzSurface = new gfxQuartzSurface(backingSize,
gfxASurface::ImageFormatARGB32);
if (mQuartzSurface->CairoStatus())
return nullptr;
mSurfaceContext = new gfxContext(mQuartzSurface);
// grab the CGContextRef
mCGContext = cairo_quartz_get_cg_context_with_clip(mSurfaceContext->GetCairo());
CGContextScaleCTM(mCGContext, mBackingScale, mBackingScale);
CGContextTranslateCTM(mCGContext, -mNativeRect.X(), -mNativeRect.Y());
}
return mCGContext;
}
void
gfxQuartzNativeDrawing::EndNativeDrawing()
{
NS_ASSERTION(mCGContext, "EndNativeDrawing called without BeginNativeDrawing");
if (mBorrowedContext.cg) {
MOZ_ASSERT(!mContext->IsCairo());
mBorrowedContext.Finish();
if (mDrawTarget) {
DrawTarget *dest = mContext->GetDrawTarget();
RefPtr<SourceSurface> source = mDrawTarget->Snapshot();
IntSize backingSize(NSToIntFloor(mNativeRect.width * mBackingScale),
NSToIntFloor(mNativeRect.height * mBackingScale));
Matrix oldTransform = dest->GetTransform();
Matrix newTransform = oldTransform;
newTransform.Translate(mNativeRect.x, mNativeRect.y);
newTransform.Scale(1.0f / mBackingScale, 1.0f / mBackingScale);
dest->SetTransform(newTransform);
dest->DrawSurface(source,
gfx::Rect(0, 0, backingSize.width, backingSize.height),
gfx::Rect(0, 0, backingSize.width, backingSize.height));
dest->SetTransform(oldTransform);
}
return;
}
cairo_quartz_finish_cg_context_with_clip(mSurfaceContext->GetCairo());
mQuartzSurface->MarkDirty();
if (mSurfaceContext != mContext) {
gfxContextMatrixAutoSaveRestore save(mContext);
// Copy back to destination
mContext->Translate(mNativeRect.TopLeft());
mContext->Scale(1.0f / mBackingScale, 1.0f / mBackingScale);
mContext->DrawSurface(mQuartzSurface, mQuartzSurface->GetSize());
}
}