1 files changed, 582 insertions, 0 deletions
diff --git a/gfx/2d/QuartzSupport.mm b/gfx/2d/QuartzSupport.mm
new file mode 100644
index 0000000000..91b754e380
--- /dev/null
+++ b/gfx/2d/QuartzSupport.mm
@@ -0,0 +1,582 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+// vim:set ts=2 sts=2 sw=2 et cin:
+/* 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 "QuartzSupport.h"
+#include "nsDebug.h"
+#include "MacIOSurface.h"
+#include "mozilla/Sprintf.h"
+
+#import <QuartzCore/QuartzCore.h>
+#import <AppKit/NSOpenGL.h>
+#import <OpenGL/CGLIOSurface.h>
+#include <dlfcn.h>
+#include "GLDefs.h"
+
+#define IOSURFACE_FRAMEWORK_PATH "/System/Library/Frameworks/IOSurface.framework/IOSurface"
+#define OPENGL_FRAMEWORK_PATH "/System/Library/Frameworks/OpenGL.framework/OpenGL"
+#define COREGRAPHICS_FRAMEWORK_PATH                                                             \
+  "/System/Library/Frameworks/ApplicationServices.framework/Frameworks/CoreGraphics.framework/" \
+  "CoreGraphics"
+
+@interface CALayer (ContentsScale)
+- (double)contentsScale;
+- (void)setContentsScale:(double)scale;
+@end
+
+CGColorSpaceRef CreateSystemColorSpace() {
+  CGColorSpaceRef cspace = ::CGDisplayCopyColorSpace(::CGMainDisplayID());
+  if (!cspace) {
+    cspace = ::CGColorSpaceCreateDeviceRGB();
+  }
+  return cspace;
+}
+
+nsCARenderer::~nsCARenderer() { Destroy(); }
+
+static void cgdata_release_callback(void* aCGData, const void* data, size_t size) {
+  if (aCGData) {
+    free(aCGData);
+  }
+}
+
+void nsCARenderer::Destroy() {
+  if (mCARenderer) {
+    CARenderer* caRenderer = (CARenderer*)mCARenderer;
+    // Bug 556453:
+    // Explicitly remove the layer from the renderer
+    // otherwise it does not always happen right away.
+    caRenderer.layer = nullptr;
+    [caRenderer release];
+  }
+  if (mWrapperCALayer) {
+    CALayer* wrapperLayer = (CALayer*)mWrapperCALayer;
+    [wrapperLayer release];
+  }
+  if (mOpenGLContext) {
+    if (mFBO || mIOTexture || mFBOTexture) {
+      // Release these resources with the context that allocated them
+      CGLContextObj oldContext = ::CGLGetCurrentContext();
+      ::CGLSetCurrentContext(mOpenGLContext);
+
+      if (mFBOTexture) {
+        ::glDeleteTextures(1, &mFBOTexture);
+      }
+      if (mIOTexture) {
+        ::glDeleteTextures(1, &mIOTexture);
+      }
+      if (mFBO) {
+        ::glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+        ::glDeleteFramebuffersEXT(1, &mFBO);
+      }
+
+      if (oldContext) ::CGLSetCurrentContext(oldContext);
+    }
+    ::CGLDestroyContext((CGLContextObj)mOpenGLContext);
+  }
+  if (mCGImage) {
+    ::CGImageRelease(mCGImage);
+  }
+  // mCGData is deallocated by cgdata_release_callback
+
+  mCARenderer = nil;
+  mWrapperCALayer = nil;
+  mFBOTexture = 0;
+  mOpenGLContext = nullptr;
+  mCGImage = nullptr;
+  mIOSurface = nullptr;
+  mFBO = 0;
+  mIOTexture = 0;
+}
+
+nsresult nsCARenderer::SetupRenderer(void* aCALayer, int aWidth, int aHeight,
+                                     double aContentsScaleFactor,
+                                     AllowOfflineRendererEnum aAllowOfflineRenderer) {
+  mAllowOfflineRenderer = aAllowOfflineRenderer;
+
+  if (aWidth == 0 || aHeight == 0 || aContentsScaleFactor <= 0) return NS_ERROR_FAILURE;
+
+  if (aWidth == mUnsupportedWidth && aHeight == mUnsupportedHeight) {
+    return NS_ERROR_FAILURE;
+  }
+
+  CGLPixelFormatAttribute attributes[] = {kCGLPFAAccelerated, kCGLPFADepthSize,
+                                          (CGLPixelFormatAttribute)24, kCGLPFAAllowOfflineRenderers,
+                                          (CGLPixelFormatAttribute)0};
+
+  if (mAllowOfflineRenderer == DISALLOW_OFFLINE_RENDERER) {
+    attributes[3] = (CGLPixelFormatAttribute)0;
+  }
+
+  GLint screen;
+  CGLPixelFormatObj format;
+  if (::CGLChoosePixelFormat(attributes, &format, &screen) != kCGLNoError) {
+    mUnsupportedWidth = aWidth;
+    mUnsupportedHeight = aHeight;
+    Destroy();
+    return NS_ERROR_FAILURE;
+  }
+
+  if (::CGLCreateContext(format, nullptr, &mOpenGLContext) != kCGLNoError) {
+    mUnsupportedWidth = aWidth;
+    mUnsupportedHeight = aHeight;
+    Destroy();
+    return NS_ERROR_FAILURE;
+  }
+  ::CGLDestroyPixelFormat(format);
+
+  CARenderer* caRenderer = [[CARenderer rendererWithCGLContext:mOpenGLContext options:nil] retain];
+  if (caRenderer == nil) {
+    mUnsupportedWidth = aWidth;
+    mUnsupportedHeight = aHeight;
+    Destroy();
+    return NS_ERROR_FAILURE;
+  }
+  CALayer* wrapperCALayer = [[CALayer layer] retain];
+  if (wrapperCALayer == nil) {
+    [caRenderer release];
+    mUnsupportedWidth = aWidth;
+    mUnsupportedHeight = aHeight;
+    Destroy();
+    return NS_ERROR_FAILURE;
+  }
+
+  mCARenderer = caRenderer;
+  mWrapperCALayer = wrapperCALayer;
+  caRenderer.layer = wrapperCALayer;
+  [wrapperCALayer addSublayer:(CALayer*)aCALayer];
+  mContentsScaleFactor = aContentsScaleFactor;
+  size_t intScaleFactor = ceil(mContentsScaleFactor);
+  SetBounds(aWidth, aHeight);
+
+  // We target rendering to a CGImage if no shared IOSurface are given.
+  if (!mIOSurface) {
+    mCGData = malloc(aWidth * intScaleFactor * aHeight * 4 * intScaleFactor);
+    if (!mCGData) {
+      mUnsupportedWidth = aWidth;
+      mUnsupportedHeight = aHeight;
+      Destroy();
+      return NS_ERROR_FAILURE;
+    }
+    memset(mCGData, 0, aWidth * intScaleFactor * aHeight * 4 * intScaleFactor);
+
+    CGDataProviderRef dataProvider = nullptr;
+    dataProvider = ::CGDataProviderCreateWithData(
+        mCGData, mCGData, aHeight * intScaleFactor * aWidth * 4 * intScaleFactor,
+        cgdata_release_callback);
+    if (!dataProvider) {
+      cgdata_release_callback(mCGData, mCGData,
+                              aHeight * intScaleFactor * aWidth * 4 * intScaleFactor);
+      mUnsupportedWidth = aWidth;
+      mUnsupportedHeight = aHeight;
+      Destroy();
+      return NS_ERROR_FAILURE;
+    }
+
+    CGColorSpaceRef colorSpace = CreateSystemColorSpace();
+
+    mCGImage = ::CGImageCreate(aWidth * intScaleFactor, aHeight * intScaleFactor, 8, 32,
+                               aWidth * intScaleFactor * 4, colorSpace,
+                               kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host,
+                               dataProvider, nullptr, true, kCGRenderingIntentDefault);
+
+    ::CGDataProviderRelease(dataProvider);
+    ::CGColorSpaceRelease(colorSpace);
+    if (!mCGImage) {
+      mUnsupportedWidth = aWidth;
+      mUnsupportedHeight = aHeight;
+      Destroy();
+      return NS_ERROR_FAILURE;
+    }
+  }
+
+  CGLContextObj oldContext = ::CGLGetCurrentContext();
+  ::CGLSetCurrentContext(mOpenGLContext);
+
+  if (mIOSurface) {
+    // Create the IOSurface mapped texture.
+    ::glGenTextures(1, &mIOTexture);
+    ::glBindTexture(GL_TEXTURE_RECTANGLE_ARB, mIOTexture);
+    ::glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    ::glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    ::CGLTexImageIOSurface2D(mOpenGLContext, GL_TEXTURE_RECTANGLE_ARB, GL_RGBA,
+                             aWidth * intScaleFactor, aHeight * intScaleFactor, GL_BGRA,
+                             GL_UNSIGNED_INT_8_8_8_8_REV, mIOSurface->GetIOSurfaceRef().get(), 0);
+    ::glBindTexture(GL_TEXTURE_RECTANGLE_ARB, 0);
+  } else {
+    ::glGenTextures(1, &mFBOTexture);
+    ::glBindTexture(GL_TEXTURE_RECTANGLE_ARB, mFBOTexture);
+    ::glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    ::glTexParameteri(GL_TEXTURE_RECTANGLE_ARB, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    ::glBindTexture(GL_TEXTURE_RECTANGLE_ARB, 0);
+  }
+
+  // Create the fbo
+  ::glGenFramebuffersEXT(1, &mFBO);
+  ::glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, mFBO);
+  if (mIOSurface) {
+    ::glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+                                GL_TEXTURE_RECTANGLE_ARB, mIOTexture, 0);
+  } else {
+    ::glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
+                                GL_TEXTURE_RECTANGLE_ARB, mFBOTexture, 0);
+  }
+
+  // Make sure that the Framebuffer configuration is supported on the client machine
+  GLenum fboStatus;
+  fboStatus = ::glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
+  if (fboStatus != GL_FRAMEBUFFER_COMPLETE_EXT) {
+    NS_ERROR("FBO not supported");
+    if (oldContext) ::CGLSetCurrentContext(oldContext);
+    mUnsupportedWidth = aWidth;
+    mUnsupportedHeight = aHeight;
+    Destroy();
+    return NS_ERROR_FAILURE;
+  }
+
+  SetViewport(aWidth, aHeight);
+
+  GLenum result = ::glGetError();
+  if (result != GL_NO_ERROR) {
+    NS_ERROR("Unexpected OpenGL Error");
+    mUnsupportedWidth = aWidth;
+    mUnsupportedHeight = aHeight;
+    Destroy();
+    if (oldContext) ::CGLSetCurrentContext(oldContext);
+    return NS_ERROR_FAILURE;
+  }
+
+  if (oldContext) ::CGLSetCurrentContext(oldContext);
+
+  return NS_OK;
+}
+
+void nsCARenderer::SetBounds(int aWidth, int aHeight) {
+  CARenderer* caRenderer = (CARenderer*)mCARenderer;
+  CALayer* wrapperLayer = (CALayer*)mWrapperCALayer;
+  NSArray* sublayers = [wrapperLayer sublayers];
+  CALayer* pluginLayer = (CALayer*)[sublayers objectAtIndex:0];
+
+  // Create a transaction and disable animations
+  // to make the position update instant.
+  [CATransaction begin];
+  NSMutableDictionary* newActions = [[NSMutableDictionary alloc]
+      initWithObjectsAndKeys:[NSNull null], @"onOrderIn", [NSNull null], @"onOrderOut",
+                             [NSNull null], @"sublayers", [NSNull null], @"contents", [NSNull null],
+                             @"position", [NSNull null], @"bounds", nil];
+  wrapperLayer.actions = newActions;
+  [newActions release];
+
+  // If we're in HiDPI mode, mContentsScaleFactor will (presumably) be 2.0.
+  // For some reason, to make things work properly in HiDPI mode we need to
+  // make caRenderer's 'bounds' and 'layer' different sizes -- to set 'bounds'
+  // to the size of 'layer's backing store.  And to avoid this possibly
+  // confusing the plugin, we need to hide it's effects from the plugin by
+  // making pluginLayer (usually the CALayer* provided by the plugin) a
+  // sublayer of our own wrapperLayer (see bug 829284).
+  size_t intScaleFactor = ceil(mContentsScaleFactor);
+  [CATransaction setValue:[NSNumber numberWithFloat:0.0f] forKey:kCATransactionAnimationDuration];
+  [CATransaction setValue:(id)kCFBooleanTrue forKey:kCATransactionDisableActions];
+  [wrapperLayer setBounds:CGRectMake(0, 0, aWidth, aHeight)];
+  [wrapperLayer setPosition:CGPointMake(aWidth / 2.0, aHeight / 2.0)];
+  [pluginLayer setBounds:CGRectMake(0, 0, aWidth, aHeight)];
+  [pluginLayer setFrame:CGRectMake(0, 0, aWidth, aHeight)];
+  caRenderer.bounds = CGRectMake(0, 0, aWidth * intScaleFactor, aHeight * intScaleFactor);
+  if (mContentsScaleFactor != 1.0) {
+    CGAffineTransform affineTransform = [wrapperLayer affineTransform];
+    affineTransform.a = mContentsScaleFactor;
+    affineTransform.d = mContentsScaleFactor;
+    affineTransform.tx = ((double)aWidth) / mContentsScaleFactor;
+    affineTransform.ty = ((double)aHeight) / mContentsScaleFactor;
+    [wrapperLayer setAffineTransform:affineTransform];
+  } else {
+    // These settings are the default values.  But they might have been
+    // changed as above if we were previously running in a HiDPI mode
+    // (i.e. if we just switched from that to a non-HiDPI mode).
+    [wrapperLayer setAffineTransform:CGAffineTransformIdentity];
+  }
+  [CATransaction commit];
+}
+
+void nsCARenderer::SetViewport(int aWidth, int aHeight) {
+  size_t intScaleFactor = ceil(mContentsScaleFactor);
+  aWidth *= intScaleFactor;
+  aHeight *= intScaleFactor;
+
+  ::glViewport(0.0, 0.0, aWidth, aHeight);
+  ::glMatrixMode(GL_PROJECTION);
+  ::glLoadIdentity();
+  ::glOrtho(0.0, aWidth, 0.0, aHeight, -1, 1);
+
+  // Render upside down to speed up CGContextDrawImage
+  ::glTranslatef(0.0f, aHeight, 0.0);
+  ::glScalef(1.0, -1.0, 1.0);
+}
+
+void nsCARenderer::AttachIOSurface(MacIOSurface* aSurface) {
+  if (mIOSurface && aSurface->GetIOSurfaceID() == mIOSurface->GetIOSurfaceID()) {
+    return;
+  }
+
+  mIOSurface = aSurface;
+
+  // Update the framebuffer and viewport
+  if (mCARenderer) {
+    CARenderer* caRenderer = (CARenderer*)mCARenderer;
+    size_t intScaleFactor = ceil(mContentsScaleFactor);
+    int width = caRenderer.bounds.size.width / intScaleFactor;
+    int height = caRenderer.bounds.size.height / intScaleFactor;
+
+    CGLContextObj oldContext = ::CGLGetCurrentContext();
+    ::CGLSetCurrentContext(mOpenGLContext);
+    ::glBindTexture(GL_TEXTURE_RECTANGLE_ARB, mIOTexture);
+    ::CGLTexImageIOSurface2D(mOpenGLContext, GL_TEXTURE_RECTANGLE_ARB, GL_RGBA,
+                             mIOSurface->GetDevicePixelWidth(), mIOSurface->GetDevicePixelHeight(),
+                             GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV,
+                             mIOSurface->GetIOSurfaceRef().get(), 0);
+    ::glBindTexture(GL_TEXTURE_RECTANGLE_ARB, 0);
+
+    // Rebind the FBO to make it live
+    ::glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, mFBO);
+
+    if (static_cast<int>(mIOSurface->GetWidth()) != width ||
+        static_cast<int>(mIOSurface->GetHeight()) != height) {
+      width = mIOSurface->GetWidth();
+      height = mIOSurface->GetHeight();
+      SetBounds(width, height);
+      SetViewport(width, height);
+    }
+
+    if (oldContext) {
+      ::CGLSetCurrentContext(oldContext);
+    }
+  }
+}
+
+IOSurfaceID nsCARenderer::GetIOSurfaceID() {
+  if (!mIOSurface) {
+    return 0;
+  }
+
+  return mIOSurface->GetIOSurfaceID();
+}
+
+nsresult nsCARenderer::Render(int aWidth, int aHeight, double aContentsScaleFactor,
+                              CGImageRef* aOutCGImage) {
+  if (!aOutCGImage && !mIOSurface) {
+    NS_ERROR("No target destination for rendering");
+  } else if (aOutCGImage) {
+    // We are expected to return a CGImageRef, we will set
+    // it to nullptr in case we fail before the image is ready.
+    *aOutCGImage = nullptr;
+  }
+
+  if (aWidth == 0 || aHeight == 0 || aContentsScaleFactor <= 0) return NS_OK;
+
+  if (!mCARenderer || !mWrapperCALayer) {
+    return NS_ERROR_FAILURE;
+  }
+
+  CARenderer* caRenderer = (CARenderer*)mCARenderer;
+  CALayer* wrapperLayer = (CALayer*)mWrapperCALayer;
+  size_t intScaleFactor = ceil(aContentsScaleFactor);
+  int renderer_width = caRenderer.bounds.size.width / intScaleFactor;
+  int renderer_height = caRenderer.bounds.size.height / intScaleFactor;
+
+  if (renderer_width != aWidth || renderer_height != aHeight ||
+      mContentsScaleFactor != aContentsScaleFactor) {
+    // XXX: This should be optimized to not rescale the buffer
+    //      if we are resizing down.
+    // caLayer may be the CALayer* provided by the plugin, so we need to
+    // preserve it across the call to Destroy().
+    NSArray* sublayers = [wrapperLayer sublayers];
+    CALayer* caLayer = (CALayer*)[sublayers objectAtIndex:0];
+    // mIOSurface is set by AttachIOSurface(), not by SetupRenderer().  So
+    // since it may have been set by a prior call to AttachIOSurface(), we
+    // need to preserve it across the call to Destroy().
+    RefPtr<MacIOSurface> ioSurface = mIOSurface;
+    Destroy();
+    mIOSurface = ioSurface;
+    if (SetupRenderer(caLayer, aWidth, aHeight, aContentsScaleFactor, mAllowOfflineRenderer) !=
+        NS_OK) {
+      return NS_ERROR_FAILURE;
+    }
+
+    caRenderer = (CARenderer*)mCARenderer;
+  }
+
+  CGLContextObj oldContext = ::CGLGetCurrentContext();
+  ::CGLSetCurrentContext(mOpenGLContext);
+  if (!mIOSurface) {
+    // If no shared IOSurface is given render to our own
+    // texture for readback.
+    ::glGenTextures(1, &mFBOTexture);
+  }
+
+  GLenum result = ::glGetError();
+  if (result != GL_NO_ERROR) {
+    NS_ERROR("Unexpected OpenGL Error");
+    Destroy();
+    if (oldContext) ::CGLSetCurrentContext(oldContext);
+    return NS_ERROR_FAILURE;
+  }
+
+  ::glClearColor(0.0, 0.0, 0.0, 0.0);
+  ::glClear(GL_COLOR_BUFFER_BIT);
+
+  [CATransaction commit];
+  double caTime = ::CACurrentMediaTime();
+  [caRenderer beginFrameAtTime:caTime timeStamp:nullptr];
+  [caRenderer addUpdateRect:CGRectMake(0, 0, aWidth * intScaleFactor, aHeight * intScaleFactor)];
+  [caRenderer render];
+  [caRenderer endFrame];
+
+  // Read the data back either to the IOSurface or mCGImage.
+  if (mIOSurface) {
+    ::glFlush();
+  } else {
+    ::glPixelStorei(GL_PACK_ALIGNMENT, 4);
+    ::glPixelStorei(GL_PACK_ROW_LENGTH, 0);
+    ::glPixelStorei(GL_PACK_SKIP_ROWS, 0);
+    ::glPixelStorei(GL_PACK_SKIP_PIXELS, 0);
+
+    ::glReadPixels(0.0f, 0.0f, aWidth * intScaleFactor, aHeight * intScaleFactor, GL_BGRA,
+                   GL_UNSIGNED_BYTE, mCGData);
+
+    *aOutCGImage = mCGImage;
+  }
+
+  if (oldContext) {
+    ::CGLSetCurrentContext(oldContext);
+  }
+
+  return NS_OK;
+}
+
+nsresult nsCARenderer::DrawSurfaceToCGContext(CGContextRef aContext, MacIOSurface* surf,
+                                              CGColorSpaceRef aColorSpace, int aX, int aY,
+                                              size_t aWidth, size_t aHeight) {
+  surf->Lock();
+  size_t bytesPerRow = surf->GetBytesPerRow();
+  size_t ioWidth = surf->GetWidth();
+  size_t ioHeight = surf->GetHeight();
+
+  // We get rendering glitches if we use a width/height that falls
+  // outside of the IOSurface.
+  if (aWidth + aX > ioWidth) aWidth = ioWidth - aX;
+  if (aHeight + aY > ioHeight) aHeight = ioHeight - aY;
+
+  if (aX < 0 || static_cast<size_t>(aX) >= ioWidth || aY < 0 ||
+      static_cast<size_t>(aY) >= ioHeight) {
+    surf->Unlock();
+    return NS_ERROR_FAILURE;
+  }
+
+  void* ioData = surf->GetBaseAddress();
+  CGDataProviderRef dataProvider =
+      ::CGDataProviderCreateWithData(ioData, ioData, ioHeight * (bytesPerRow)*4,
+                                     nullptr);  // No release callback
+  if (!dataProvider) {
+    surf->Unlock();
+    return NS_ERROR_FAILURE;
+  }
+
+  CGImageRef cgImage = ::CGImageCreate(ioWidth, ioHeight, 8, 32, bytesPerRow, aColorSpace,
+                                       kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host,
+                                       dataProvider, nullptr, true, kCGRenderingIntentDefault);
+  ::CGDataProviderRelease(dataProvider);
+  if (!cgImage) {
+    surf->Unlock();
+    return NS_ERROR_FAILURE;
+  }
+  CGImageRef subImage =
+      ::CGImageCreateWithImageInRect(cgImage, ::CGRectMake(aX, aY, aWidth, aHeight));
+  if (!subImage) {
+    ::CGImageRelease(cgImage);
+    surf->Unlock();
+    return NS_ERROR_FAILURE;
+  }
+
+  ::CGContextScaleCTM(aContext, 1.0f, -1.0f);
+  ::CGContextDrawImage(aContext, CGRectMake(aX, -(CGFloat)aY - (CGFloat)aHeight, aWidth, aHeight),
+                       subImage);
+
+  ::CGImageRelease(subImage);
+  ::CGImageRelease(cgImage);
+  surf->Unlock();
+  return NS_OK;
+}
+
+void nsCARenderer::DetachCALayer() {
+  CALayer* wrapperLayer = (CALayer*)mWrapperCALayer;
+  NSArray* sublayers = [wrapperLayer sublayers];
+  CALayer* oldLayer = (CALayer*)[sublayers objectAtIndex:0];
+  [oldLayer removeFromSuperlayer];
+}
+
+void nsCARenderer::AttachCALayer(void* aCALayer) {
+  CALayer* wrapperLayer = (CALayer*)mWrapperCALayer;
+  NSArray* sublayers = [wrapperLayer sublayers];
+  CALayer* oldLayer = (CALayer*)[sublayers objectAtIndex:0];
+  [oldLayer removeFromSuperlayer];
+  [wrapperLayer addSublayer:(CALayer*)aCALayer];
+}
+
+#ifdef DEBUG
+
+int sSaveToDiskSequence = 0;
+void nsCARenderer::SaveToDisk(MacIOSurface* surf) {
+  surf->Lock();
+  size_t bytesPerRow = surf->GetBytesPerRow();
+  size_t ioWidth = surf->GetWidth();
+  size_t ioHeight = surf->GetHeight();
+  void* ioData = surf->GetBaseAddress();
+  CGDataProviderRef dataProvider =
+      ::CGDataProviderCreateWithData(ioData, ioData, ioHeight * (bytesPerRow)*4,
+                                     nullptr);  // No release callback
+  if (!dataProvider) {
+    surf->Unlock();
+    return;
+  }
+
+  CGColorSpaceRef colorSpace = CreateSystemColorSpace();
+  CGImageRef cgImage = ::CGImageCreate(ioWidth, ioHeight, 8, 32, bytesPerRow, colorSpace,
+                                       kCGImageAlphaPremultipliedFirst | kCGBitmapByteOrder32Host,
+                                       dataProvider, nullptr, true, kCGRenderingIntentDefault);
+  ::CGDataProviderRelease(dataProvider);
+  ::CGColorSpaceRelease(colorSpace);
+  if (!cgImage) {
+    surf->Unlock();
+    return;
+  }
+
+  char cstr[1000];
+  SprintfLiteral(cstr, "file:///Users/benoitgirard/debug/iosurface_%i.png", ++sSaveToDiskSequence);
+
+  CFStringRef cfStr =
+      ::CFStringCreateWithCString(kCFAllocatorDefault, cstr, kCFStringEncodingMacRoman);
+
+  printf("Exporting: %s\n", cstr);
+  CFURLRef url = ::CFURLCreateWithString(nullptr, cfStr, nullptr);
+  ::CFRelease(cfStr);
+
+  CFStringRef type = kUTTypePNG;
+  size_t count = 1;
+  CFDictionaryRef options = nullptr;
+  CGImageDestinationRef dest = ::CGImageDestinationCreateWithURL(url, type, count, options);
+  ::CFRelease(url);
+
+  ::CGImageDestinationAddImage(dest, cgImage, nullptr);
+
+  ::CGImageDestinationFinalize(dest);
+  ::CFRelease(dest);
+  ::CGImageRelease(cgImage);
+
+  surf->Unlock();
+
+  return;
+}
+
+#endif