void
LayerManagerComposite::WorldTransformRect(nsIntRect& aRect)
{
  gfx::Rect grect(aRect.x, aRect.y, aRect.width, aRect.height);
  grect = mWorldMatrix.TransformBounds(grect);
  aRect.SetRect(grect.X(), grect.Y(), grect.Width(), grect.Height());
}

already_AddRefed<gfxContext>
ThebesLayerBuffer::GetContextForQuadrantUpdate(const nsIntRect& aBounds)
{
  nsRefPtr<gfxContext> ctx = new gfxContext(mBuffer);

  // Figure out which quadrant to draw in
  PRInt32 xBoundary = mBufferRect.XMost() - mBufferRotation.x;
  PRInt32 yBoundary = mBufferRect.YMost() - mBufferRotation.y;
  XSide sideX = aBounds.XMost() <= xBoundary ? RIGHT : LEFT;
  YSide sideY = aBounds.YMost() <= yBoundary ? BOTTOM : TOP;
  nsIntRect quadrantRect = GetQuadrantRectangle(sideX, sideY);
  NS_ASSERTION(quadrantRect.Contains(aBounds), "Messed up quadrants");
  ctx->Translate(-gfxPoint(quadrantRect.x, quadrantRect.y));

  return ctx.forget();
}

static void CalculatePluginClip(const nsIntRect& aBounds,
                                const nsTArray<nsIntRect>& aPluginClipRects,
                                const nsIntPoint& aContentOffset,
                                const nsIntRegion& aParentLayerVisibleRegion,
                                nsTArray<nsIntRect>& aResult,
                                nsIntRect& aVisibleBounds,
                                bool& aPluginIsVisible)
{
  aPluginIsVisible = true;
  // aBounds (content origin)
  nsIntRegion contentVisibleRegion(aBounds);
  // aPluginClipRects (plugin widget origin)
  for (uint32_t idx = 0; idx < aPluginClipRects.Length(); idx++) {
    nsIntRect rect = aPluginClipRects[idx];
    // shift to content origin
    rect.MoveBy(aBounds.x, aBounds.y);
    contentVisibleRegion.AndWith(rect);
  }
  // apply layers clip (window origin)
  nsIntRegion region = aParentLayerVisibleRegion;
  region.MoveBy(-aContentOffset.x, -aContentOffset.y);
  contentVisibleRegion.AndWith(region);
  if (contentVisibleRegion.IsEmpty()) {
    aPluginIsVisible = false;
    return;
  }
  // shift to plugin widget origin
  contentVisibleRegion.MoveBy(-aBounds.x, -aBounds.y);
  nsIntRegionRectIterator iter(contentVisibleRegion);
  for (const nsIntRect* rgnRect = iter.Next(); rgnRect; rgnRect = iter.Next()) {
    aResult.AppendElement(*rgnRect);
    aVisibleBounds.UnionRect(aVisibleBounds, *rgnRect);
  }
}

// Computes the smallest rectangle that contains both aRect1 and aRect2 and
// fills 'this' with the result. Returns FALSE if both aRect1 and aRect2 are
// empty and TRUE otherwise
PRBool nsIntRect::UnionRect(const nsIntRect &aRect1, const nsIntRect &aRect2)
{
  PRBool  result = PR_TRUE;

  // Is aRect1 empty?
  if (aRect1.IsEmpty()) {
    if (aRect2.IsEmpty()) {
      // Both rectangles are empty which is an error
      Empty();
      result = PR_FALSE;
    } else {
      // aRect1 is empty so set the result to aRect2
      *this = aRect2;
    }
  } else if (aRect2.IsEmpty()) {
    // aRect2 is empty so set the result to aRect1
    *this = aRect1;
  } else {
    PRInt32 xmost1 = aRect1.XMost();
    PRInt32 xmost2 = aRect2.XMost();
    PRInt32 ymost1 = aRect1.YMost();
    PRInt32 ymost2 = aRect2.YMost();

    // Compute the origin
    x = PR_MIN(aRect1.x, aRect2.x);
    y = PR_MIN(aRect1.y, aRect2.y);

    // Compute the size
    width = PR_MAX(xmost1, xmost2) - x;
    height = PR_MAX(ymost1, ymost2) - y;
  }

  return result;
}

/* static */ void
ProgressTracker::SyncNotifyInternal(ObserverArray& aObservers,
                                    bool aHasImage,
                                    Progress aProgress,
                                    const nsIntRect& aDirtyRect)
{
  MOZ_ASSERT(NS_IsMainThread());

  typedef imgINotificationObserver I;

  if (aProgress & FLAG_SIZE_AVAILABLE) {
    NOTIFY_IMAGE_OBSERVERS(aObservers, Notify(I::SIZE_AVAILABLE));
  }

  if (aProgress & FLAG_ONLOAD_BLOCKED) {
    NOTIFY_IMAGE_OBSERVERS(aObservers, BlockOnload());
  }

  if (aHasImage) {
    // OnFrameUpdate
    // If there's any content in this frame at all (always true for
    // vector images, true for raster images that have decoded at
    // least one frame) then send OnFrameUpdate.
    if (!aDirtyRect.IsEmpty()) {
      NOTIFY_IMAGE_OBSERVERS(aObservers, Notify(I::FRAME_UPDATE, &aDirtyRect));
    }

    if (aProgress & FLAG_FRAME_COMPLETE) {
      NOTIFY_IMAGE_OBSERVERS(aObservers, Notify(I::FRAME_COMPLETE));
    }

    if (aProgress & FLAG_HAS_TRANSPARENCY) {
      NOTIFY_IMAGE_OBSERVERS(aObservers, Notify(I::HAS_TRANSPARENCY));
    }

    if (aProgress & FLAG_IS_ANIMATED) {
      NOTIFY_IMAGE_OBSERVERS(aObservers, Notify(I::IS_ANIMATED));
    }
  }

  // Send UnblockOnload before OnStopDecode and OnStopRequest. This allows
  // observers that can fire events when they receive those notifications to do
  // so then, instead of being forced to wait for UnblockOnload.
  if (aProgress & FLAG_ONLOAD_UNBLOCKED) {
    NOTIFY_IMAGE_OBSERVERS(aObservers, UnblockOnload());
  }

  if (aProgress & FLAG_DECODE_COMPLETE) {
    MOZ_ASSERT(aHasImage, "Stopped decoding without ever having an image?");
    NOTIFY_IMAGE_OBSERVERS(aObservers, Notify(I::DECODE_COMPLETE));
  }

  if (aProgress & FLAG_LOAD_COMPLETE) {
    NOTIFY_IMAGE_OBSERVERS(aObservers,
                           OnLoadComplete(aProgress & FLAG_LAST_PART_COMPLETE));
  }
}

void
nsSVGUtils::ConvertImageDataFromLinearRGB(PRUint8 *data, 
                                          PRInt32 stride,
                                          const nsIntRect &rect)
{
  for (PRInt32 y = rect.y; y < rect.YMost(); y++) {
    for (PRInt32 x = rect.x; x < rect.XMost(); x++) {
      PRUint8 *pixel = data + stride * y + 4 * x;

      pixel[GFX_ARGB32_OFFSET_B] =
        glinearRGBTosRGBMap[pixel[GFX_ARGB32_OFFSET_B]];
      pixel[GFX_ARGB32_OFFSET_G] =
        glinearRGBTosRGBMap[pixel[GFX_ARGB32_OFFSET_G]];
      pixel[GFX_ARGB32_OFFSET_R] =
        glinearRGBTosRGBMap[pixel[GFX_ARGB32_OFFSET_R]];
    }
  }
}

// Clip aTarget's image to its filter primitive subregion.
// aModifiedRect contains all the pixels which might not be RGBA(0,0,0,0),
// it's relative to the surface data.
static void
ClipTarget(nsSVGFilterInstance* aInstance, const nsSVGFE::Image* aTarget,
           const nsIntRect& aModifiedRect)
{
  nsIntPoint surfaceTopLeft = aInstance->GetSurfaceRect().TopLeft();

  NS_ASSERTION(aInstance->GetSurfaceRect().Contains(aModifiedRect + surfaceTopLeft),
               "Modified data area overflows the surface?");

  nsIntRect clip = aModifiedRect;
  nsSVGUtils::ClipToGfxRect(&clip,
    aTarget->mFilterPrimitiveSubregion - gfxPoint(surfaceTopLeft.x, surfaceTopLeft.y));

  ClearRect(aTarget->mImage, aModifiedRect.x, aModifiedRect.y, aModifiedRect.XMost(), clip.y);
  ClearRect(aTarget->mImage, aModifiedRect.x, clip.y, clip.x, clip.YMost());
  ClearRect(aTarget->mImage, clip.XMost(), clip.y, aModifiedRect.XMost(), clip.YMost());
  ClearRect(aTarget->mImage, aModifiedRect.x, clip.YMost(), aModifiedRect.XMost(), aModifiedRect.YMost());
}

/* static */ void
ProgressTracker::SyncNotifyInternal(ProxyArray& aProxies,
                                    bool aHasImage,
                                    Progress aProgress,
                                    const nsIntRect& aDirtyRect)
{
  MOZ_ASSERT(NS_IsMainThread());
  // OnStartRequest
  if (aProgress & FLAG_REQUEST_STARTED)
    NOTIFY_IMAGE_OBSERVERS(aProxies, OnStartRequest());

  // OnStartContainer
  if (aProgress & FLAG_HAS_SIZE)
    NOTIFY_IMAGE_OBSERVERS(aProxies, OnStartContainer());

  // OnStartDecode
  if (aProgress & FLAG_DECODE_STARTED)
    NOTIFY_IMAGE_OBSERVERS(aProxies, OnStartDecode());

  // BlockOnload
  if (aProgress & FLAG_ONLOAD_BLOCKED)
    NOTIFY_IMAGE_OBSERVERS(aProxies, BlockOnload());

  if (aHasImage) {
    // OnFrameUpdate
    // If there's any content in this frame at all (always true for
    // vector images, true for raster images that have decoded at
    // least one frame) then send OnFrameUpdate.
    if (!aDirtyRect.IsEmpty())
      NOTIFY_IMAGE_OBSERVERS(aProxies, OnFrameUpdate(&aDirtyRect));

    if (aProgress & FLAG_FRAME_STOPPED)
      NOTIFY_IMAGE_OBSERVERS(aProxies, OnStopFrame());

    // OnImageIsAnimated
    if (aProgress & FLAG_IS_ANIMATED)
      NOTIFY_IMAGE_OBSERVERS(aProxies, OnImageIsAnimated());
  }

  // Send UnblockOnload before OnStopDecode and OnStopRequest. This allows
  // observers that can fire events when they receive those notifications to do
  // so then, instead of being forced to wait for UnblockOnload.
  if (aProgress & FLAG_ONLOAD_UNBLOCKED) {
    NOTIFY_IMAGE_OBSERVERS(aProxies, UnblockOnload());
  }

  if (aProgress & FLAG_DECODE_STOPPED) {
    MOZ_ASSERT(aHasImage, "Stopped decoding without ever having an image?");
    NOTIFY_IMAGE_OBSERVERS(aProxies, OnStopDecode());
  }

  if (aProgress & FLAG_REQUEST_STOPPED) {
    NOTIFY_IMAGE_OBSERVERS(aProxies,
                           OnStopRequest(aProgress & FLAG_MULTIPART_STOPPED));
  }
}

void
CopyDataRect(uint8_t *aDest, const uint8_t *aSrc, uint32_t aStride,
             const nsIntRect& aDataRect)
{
  for (int32_t y = aDataRect.y; y < aDataRect.YMost(); y++) {
    memcpy(aDest + y * aStride + 4 * aDataRect.x,
           aSrc + y * aStride + 4 * aDataRect.x,
           4 * aDataRect.width);
  }
}

nsRect
nsFilterInstance::FilterSpaceToFrameSpace(const nsIntRect& aRect) const
{
  if (aRect.IsEmpty()) {
    return nsRect();
  }
  gfxRect r(aRect.x, aRect.y, aRect.width, aRect.height);
  r = mFilterSpaceToFrameSpaceInCSSPxTransform.TransformBounds(r);
  return nsLayoutUtils::RoundGfxRectToAppRect(r, mAppUnitsPerCSSPx);
}

already_AddRefed<gfxContext>
RotatedContentBuffer::GetContextForQuadrantUpdate(const nsIntRect& aBounds,
                                                  ContextSource aSource,
                                                  nsIntPoint *aTopLeft)
{
  if (!EnsureBuffer()) {
    return nullptr;
  }

  nsRefPtr<gfxContext> ctx;
  if (aSource == BUFFER_BOTH && HaveBufferOnWhite()) {
    if (!EnsureBufferOnWhite()) {
      return nullptr;
    }
    MOZ_ASSERT(mDTBuffer && mDTBufferOnWhite);
    RefPtr<DrawTarget> dualDT = Factory::CreateDualDrawTarget(mDTBuffer, mDTBufferOnWhite);
    ctx = new gfxContext(dualDT);
  } else if (aSource == BUFFER_WHITE) {
    if (!EnsureBufferOnWhite()) {
      return nullptr;
    }
    ctx = new gfxContext(mDTBufferOnWhite);
  } else {
    // BUFFER_BLACK, or BUFFER_BOTH with a single buffer.
    ctx = new gfxContext(mDTBuffer);
  }

  // Figure out which quadrant to draw in
  int32_t xBoundary = mBufferRect.XMost() - mBufferRotation.x;
  int32_t yBoundary = mBufferRect.YMost() - mBufferRotation.y;
  XSide sideX = aBounds.XMost() <= xBoundary ? RIGHT : LEFT;
  YSide sideY = aBounds.YMost() <= yBoundary ? BOTTOM : TOP;
  nsIntRect quadrantRect = GetQuadrantRectangle(sideX, sideY);
  NS_ASSERTION(quadrantRect.Contains(aBounds), "Messed up quadrants");
  ctx->Translate(-gfxPoint(quadrantRect.x, quadrantRect.y));

  if (aTopLeft) {
    *aTopLeft = nsIntPoint(quadrantRect.x, quadrantRect.y);
  }

  return ctx.forget();
}

/* static */ bool
HwcUtils::PrepareLayerRects(nsIntRect aVisible,
                            const gfx::Matrix& aLayerTransform,
                            const gfx::Matrix& aLayerBufferTransform,
                            nsIntRect aClip, nsIntRect aBufferRect,
                            bool aYFlipped,
                            hwc_rect_t* aSourceCrop, hwc_rect_t* aVisibleRegionScreen) {

    gfxMatrix aTransform = gfx::ThebesMatrix(aLayerTransform);
    gfxRect visibleRect(aVisible);
    gfxRect clip(aClip);
    gfxRect visibleRectScreen = aTransform.TransformBounds(visibleRect);
    // |clip| is guaranteed to be integer
    visibleRectScreen.IntersectRect(visibleRectScreen, clip);

    if (visibleRectScreen.IsEmpty()) {
        return false;
    }

    gfxMatrix inverse = gfx::ThebesMatrix(aLayerBufferTransform);
    inverse.Invert();
    gfxRect crop = inverse.TransformBounds(visibleRectScreen);

    //clip to buffer size
    crop.IntersectRect(crop, aBufferRect);
    crop.Round();

    if (crop.IsEmpty()) {
        return false;
    }

    //propagate buffer clipping back to visible rect
    gfxMatrix layerBufferTransform = gfx::ThebesMatrix(aLayerBufferTransform);
    visibleRectScreen = layerBufferTransform.TransformBounds(crop);
    visibleRectScreen.Round();

    // Map from layer space to buffer space
    crop -= aBufferRect.TopLeft();
    if (aYFlipped) {
        crop.y = aBufferRect.height - (crop.y + crop.height);
    }

    aSourceCrop->left = crop.x;
    aSourceCrop->top  = crop.y;
    aSourceCrop->right  = crop.x + crop.width;
    aSourceCrop->bottom = crop.y + crop.height;

    aVisibleRegionScreen->left = visibleRectScreen.x;
    aVisibleRegionScreen->top  = visibleRectScreen.y;
    aVisibleRegionScreen->right  = visibleRectScreen.x + visibleRectScreen.width;
    aVisibleRegionScreen->bottom = visibleRectScreen.y + visibleRectScreen.height;

    return true;
}

void
AndroidGeckoLayerClient::SetFirstPaintViewport(const nsIntPoint& aOffset, float aZoom, const nsIntRect& aPageRect, const gfx::Rect& aCssPageRect)
{
    NS_ASSERTION(!isNull(), "SetFirstPaintViewport called on null layer client!");
    JNIEnv *env = GetJNIForThread();    // this is called on the compositor thread
    if (!env)
        return;

    AutoLocalJNIFrame jniFrame(env, 0);
    return env->CallVoidMethod(wrapped_obj, jSetFirstPaintViewport, (float)aOffset.x, (float)aOffset.y, aZoom,
                               (float)aPageRect.x, (float)aPageRect.y, (float)aPageRect.XMost(), (float)aPageRect.YMost(),
                               aCssPageRect.x, aCssPageRect.y, aCssPageRect.XMost(), aCssPageRect.YMost());
}

static void
ComputeLinearRGBLuminanceMask(uint8_t *aData,
                              int32_t aStride,
                              const nsIntRect &aRect,
                              float aOpacity)
{
    for (int32_t y = aRect.y; y < aRect.YMost(); y++) {
        for (int32_t x = aRect.x; x < aRect.XMost(); x++) {
            uint8_t *pixel = aData + aStride * y + 4 * x;
            uint8_t a = pixel[GFX_ARGB32_OFFSET_A];

            uint8_t luminance;
            // unpremultiply
            if (a) {
                if (a != 255) {
                    pixel[GFX_ARGB32_OFFSET_B] =
                        (255 * pixel[GFX_ARGB32_OFFSET_B]) / a;
                    pixel[GFX_ARGB32_OFFSET_G] =
                        (255 * pixel[GFX_ARGB32_OFFSET_G]) / a;
                    pixel[GFX_ARGB32_OFFSET_R] =
                        (255 * pixel[GFX_ARGB32_OFFSET_R]) / a;
                }

                /* sRGB -> linearRGB -> intensity */
                luminance =
                    static_cast<uint8_t>
                    ((gsRGBToLinearRGBMap[pixel[GFX_ARGB32_OFFSET_R]] *
                      0.2125 +
                      gsRGBToLinearRGBMap[pixel[GFX_ARGB32_OFFSET_G]] *
                      0.7154 +
                      gsRGBToLinearRGBMap[pixel[GFX_ARGB32_OFFSET_B]] *
                      0.0721) * (a / 255.0) * aOpacity);
            } else {
                luminance = 0;
            }
            memset(pixel, luminance, 4);
        }
    }
}

/* static */
void
WinUtils::InvalidatePluginAsWorkaround(nsIWidget *aWidget, const nsIntRect &aRect)
{
  aWidget->Invalidate(aRect);

  // XXX - Even more evil workaround!! See bug 762948, flash's bottom
  // level sandboxed window doesn't seem to get our invalidate. We send
  // an invalidate to it manually. This is totally specialized for this
  // bug, for other child window structures this will just be a more or
  // less bogus invalidate but since that should not have any bad
  // side-effects this will have to do for now.
  HWND current = (HWND)aWidget->GetNativeData(NS_NATIVE_WINDOW);

  RECT windowRect;
  RECT parentRect;

  ::GetWindowRect(current, &parentRect);

  HWND next = current;
  do {
    current = next;
    ::EnumChildWindows(current, &EnumFirstChild, (LPARAM)&next);
    ::GetWindowRect(next, &windowRect);
    // This is relative to the screen, adjust it to be relative to the
    // window we're reconfiguring.
    windowRect.left -= parentRect.left;
    windowRect.top -= parentRect.top;
  } while (next != current && windowRect.top == 0 && windowRect.left == 0);

  if (windowRect.top == 0 && windowRect.left == 0) {
    RECT rect;
    rect.left   = aRect.x;
    rect.top    = aRect.y;
    rect.right  = aRect.XMost();
    rect.bottom = aRect.YMost();

    ::InvalidateRect(next, &rect, FALSE);
  }
}

bool imgFrame::Draw(gfxContext *aContext, GraphicsFilter aFilter,
                    const gfxMatrix &aUserSpaceToImageSpace, const gfxRect& aFill,
                    const nsIntMargin &aPadding, const nsIntRect &aSubimage,
                    uint32_t aImageFlags)
{
  PROFILER_LABEL("image", "imgFrame::Draw");
  NS_ASSERTION(!aFill.IsEmpty(), "zero dest size --- fix caller");
  NS_ASSERTION(!aSubimage.IsEmpty(), "zero source size --- fix caller");
  NS_ASSERTION(!mPalettedImageData, "Directly drawing a paletted image!");

  bool doPadding = aPadding != nsIntMargin(0,0,0,0);
  bool doPartialDecode = !ImageComplete();

  if (mSinglePixel && !doPadding && !doPartialDecode) {
    DoSingleColorFastPath(aContext, mSinglePixelColor, aFill);
    return true;
  }

  gfxMatrix userSpaceToImageSpace = aUserSpaceToImageSpace;
  gfxRect sourceRect = userSpaceToImageSpace.TransformBounds(aFill);
  gfxRect imageRect(0, 0, mSize.width + aPadding.LeftRight(),
                    mSize.height + aPadding.TopBottom());
  gfxRect subimage(aSubimage.x, aSubimage.y, aSubimage.width, aSubimage.height);
  gfxRect fill = aFill;

  NS_ASSERTION(!sourceRect.Intersect(subimage).IsEmpty(),
               "We must be allowed to sample *some* source pixels!");

  nsRefPtr<gfxASurface> surf;
  if (!mSinglePixel) {
    surf = ThebesSurface();
    if (!surf)
      return false;
  }

  bool doTile = !imageRect.Contains(sourceRect) &&
                !(aImageFlags & imgIContainer::FLAG_CLAMP);
  SurfaceWithFormat surfaceResult =
    SurfaceForDrawing(doPadding, doPartialDecode, doTile, aPadding,
                      userSpaceToImageSpace, fill, subimage, sourceRect,
                      imageRect, surf);

  if (surfaceResult.IsValid()) {
    gfxUtils::DrawPixelSnapped(aContext, surfaceResult.mDrawable,
                               userSpaceToImageSpace,
                               subimage, sourceRect, imageRect, fill,
                               surfaceResult.mFormat, aFilter, aImageFlags);
  }
  return true;
}

/**
 * Sets hwc layer rectangles required for hwc composition
 *
 * @param aVisible Input. Layer's unclipped visible rectangle
 *        The origin is the top-left corner of the layer
 * @param aTransform Input. Layer's transformation matrix
 *        It transforms from layer space to screen space
 * @param aClip Input. A clipping rectangle.
 *        The origin is the top-left corner of the screen
 * @param aBufferRect Input. The layer's buffer bounds
 *        The origin is the top-left corner of the layer
 * @param aSurceCrop Output. Area of the source to consider,
 *        the origin is the top-left corner of the buffer
 * @param aVisibleRegionScreen Output. Visible region in screen space.
 *        The origin is the top-left corner of the screen
 * @return true if the layer should be rendered.
 *         false if the layer can be skipped
 */
static bool
PrepareLayerRects(nsIntRect aVisible, const gfxMatrix& aTransform,
                  nsIntRect aClip, nsIntRect aBufferRect,
                  hwc_rect_t* aSourceCrop, hwc_rect_t* aVisibleRegionScreen) {

    gfxRect visibleRect(aVisible);
    gfxRect clip(aClip);
    gfxRect visibleRectScreen = aTransform.TransformBounds(visibleRect);
    // |clip| is guaranteed to be integer
    visibleRectScreen.IntersectRect(visibleRectScreen, clip);

    if (visibleRectScreen.IsEmpty()) {
        LOGD("Skip layer");
        return false;
    }

    gfxMatrix inverse(aTransform);
    inverse.Invert();
    gfxRect crop = inverse.TransformBounds(visibleRectScreen);

    //clip to buffer size
    crop.IntersectRect(crop, aBufferRect);
    crop.RoundOut();

    if (crop.IsEmpty()) {
        LOGD("Skip layer");
        return false;
    }

    //propagate buffer clipping back to visible rect
    visibleRectScreen = aTransform.TransformBounds(crop);
    visibleRectScreen.RoundOut();

    // Map from layer space to buffer space
    crop -= aBufferRect.TopLeft();

    aSourceCrop->left = crop.x;
    aSourceCrop->top  = crop.y;
    aSourceCrop->right  = crop.x + crop.width;
    aSourceCrop->bottom = crop.y + crop.height;

    aVisibleRegionScreen->left = visibleRectScreen.x;
    aVisibleRegionScreen->top  = visibleRectScreen.y;
    aVisibleRegionScreen->right  = visibleRectScreen.x + visibleRectScreen.width;
    aVisibleRegionScreen->bottom = visibleRectScreen.y + visibleRectScreen.height;

    return true;
}

nsIntRect
nsSVGIntegrationUtils::AdjustInvalidAreaForSVGEffects(nsIFrame* aFrame,
                                                      const nsPoint& aToReferenceFrame,
                                                      const nsIntRect& aInvalidRect)
{
  // Don't bother calling GetEffectProperties; the filter property should
  // already have been set up during reflow/ComputeFrameEffectsRect
  nsIFrame* firstFrame =
    nsLayoutUtils::GetFirstContinuationOrSpecialSibling(aFrame);
  nsSVGEffects::EffectProperties effectProperties =
    nsSVGEffects::GetEffectProperties(firstFrame);
  if (!effectProperties.mFilter)
    return aInvalidRect;

  nsSVGFilterProperty *prop = nsSVGEffects::GetFilterProperty(firstFrame);
  if (!prop || !prop->IsInObserverList()) {
    return aInvalidRect;
  }

  int32_t appUnitsPerDevPixel = aFrame->PresContext()->AppUnitsPerDevPixel();

  nsSVGFilterFrame* filterFrame = prop->GetFilterFrame();
  if (!filterFrame) {
    // The frame is either not there or not currently available,
    // perhaps because we're in the middle of tearing stuff down.
    // Be conservative, return our visual overflow rect relative
    // to the reference frame.
    nsRect overflow = aFrame->GetVisualOverflowRect() + aToReferenceFrame;
    return overflow.ToOutsidePixels(appUnitsPerDevPixel);
  }

  // Convert aInvalidRect into "user space" in app units:
  nsPoint toUserSpace =
    aFrame->GetOffsetTo(firstFrame) + GetOffsetToUserSpace(firstFrame);
  // The initial rect was relative to the reference frame, so we need to
  // remove that offset to get a rect relative to the current frame.
  toUserSpace -= aToReferenceFrame;
  nsRect preEffectsRect = aInvalidRect.ToAppUnits(appUnitsPerDevPixel) + toUserSpace;

  // Adjust the dirty area for effects, and shift it back to being relative to
  // the reference frame.
  nsRect result = filterFrame->GetPostFilterDirtyArea(firstFrame, preEffectsRect) -
           toUserSpace;
  // Return the result, in pixels relative to the reference frame.
  return result.ToOutsidePixels(appUnitsPerDevPixel);
}

static nsIntRect
TransformRect(const nsIntRect& aRect, const gfx3DMatrix& aTransform)
{
    if (aRect.IsEmpty()) {
        return nsIntRect();
    }

    gfxRect rect(aRect.x, aRect.y, aRect.width, aRect.height);
    rect = aTransform.TransformBounds(rect);
    rect.RoundOut();

    nsIntRect intRect;
    if (!gfxUtils::GfxRectToIntRect(rect, &intRect)) {
        return nsIntRect();
    }

    return intRect;
}

//******************************************************************************
void
FrameAnimator::ClearFrame(uint8_t* aFrameData, const nsIntRect& aFrameRect,
                          const nsIntRect& aRectToClear)
{
  if (!aFrameData || aFrameRect.width <= 0 || aFrameRect.height <= 0 ||
      aRectToClear.width <= 0 || aRectToClear.height <= 0) {
    return;
  }

  nsIntRect toClear = aFrameRect.Intersect(aRectToClear);
  if (toClear.IsEmpty()) {
    return;
  }

  uint32_t bytesPerRow = aFrameRect.width * 4;
  for (int row = toClear.y; row < toClear.y + toClear.height; ++row) {
    memset(aFrameData + toClear.x * 4 + row * bytesPerRow, 0,
           toClear.width * 4);
  }
}