C++ ShadowLayer::SetShadowVisibleRegion方法代码示例

// Go down shadow layer tree and apply transformations for scrollable layers.
static void
TransformShadowTree(nsDisplayListBuilder* aBuilder, nsFrameLoader* aFrameLoader,
                    nsIFrame* aFrame, Layer* aLayer,
                    const ViewTransform& aTransform)
{
  ShadowLayer* shadow = aLayer->AsShadowLayer();
  shadow->SetShadowClipRect(aLayer->GetClipRect());
  shadow->SetShadowVisibleRegion(aLayer->GetVisibleRegion());

  const FrameMetrics* metrics = GetFrameMetrics(aLayer);

  gfx3DMatrix shadowTransform;
  ViewTransform layerTransform = aTransform;

  if (metrics && metrics->IsScrollable()) {
    const ViewID scrollId = metrics->mScrollId;
    const nsContentView* view =
      aFrameLoader->GetCurrentRemoteFrame()->GetContentView(scrollId);
    NS_ABORT_IF_FALSE(view, "Array of views should be consistent with layer tree");
    const gfx3DMatrix& currentTransform = aLayer->GetTransform();

    ViewTransform viewTransform = ComputeShadowTreeTransform(
      aFrame, aFrameLoader, metrics, view->GetViewConfig(),
      1 / (GetXScale(currentTransform)*layerTransform.mXScale),
      1 / (GetYScale(currentTransform)*layerTransform.mYScale)
    );

    // Apply the layer's own transform *before* the view transform
    shadowTransform = gfx3DMatrix(viewTransform) * currentTransform;

    if (metrics->IsRootScrollable()) {
      layerTransform.mTranslation = viewTransform.mTranslation;
      // Apply the root frame translation *before* we do the rest of the transforms.
      nsIntPoint rootFrameOffset = GetRootFrameOffset(aFrame, aBuilder);
      shadowTransform = shadowTransform *
          gfx3DMatrix::Translation(float(rootFrameOffset.x), float(rootFrameOffset.y), 0.0);
      layerTransform.mXScale *= GetXScale(currentTransform);
      layerTransform.mYScale *= GetYScale(currentTransform);
    }
  } else {
    shadowTransform = aLayer->GetTransform();
  }

  if (aLayer->GetIsFixedPosition() &&
      !aLayer->GetParent()->GetIsFixedPosition()) {
    ReverseTranslate(shadowTransform, layerTransform);
    const nsIntRect* clipRect = shadow->GetShadowClipRect();
    if (clipRect) {
      nsIntRect transformedClipRect(*clipRect);
      transformedClipRect.MoveBy(shadowTransform._41, shadowTransform._42);
      shadow->SetShadowClipRect(&transformedClipRect);
    }
  }

  shadow->SetShadowTransform(shadowTransform);
  for (Layer* child = aLayer->GetFirstChild();
       child; child = child->GetNextSibling()) {
    TransformShadowTree(aBuilder, aFrameLoader, aFrame, child, layerTransform);
  }
}

// Go down shadow layer tree, setting properties to match their non-shadow
// counterparts.
static void
SetShadowProperties(Layer* aLayer)
{
  // FIXME: Bug 717688 -- Do these updates in ShadowLayersParent::RecvUpdate.
  ShadowLayer* shadow = aLayer->AsShadowLayer();
  shadow->SetShadowTransform(aLayer->GetTransform());
  shadow->SetShadowVisibleRegion(aLayer->GetVisibleRegion());
  shadow->SetShadowClipRect(aLayer->GetClipRect());

  for (Layer* child = aLayer->GetFirstChild();
      child; child = child->GetNextSibling()) {
    SetShadowProperties(child);
  }
}

// Go down shadow layer tree and apply transformations for scrollable layers.
static void
TransformShadowTree(nsDisplayListBuilder* aBuilder, nsFrameLoader* aFrameLoader,
                    nsIFrame* aFrame, Layer* aLayer,
                    const ViewTransform& aTransform,
                    float aTempScaleDiffX = 1.0,
                    float aTempScaleDiffY = 1.0)
{
  ShadowLayer* shadow = aLayer->AsShadowLayer();
  shadow->SetShadowClipRect(aLayer->GetClipRect());
  shadow->SetShadowVisibleRegion(aLayer->GetVisibleRegion());
  shadow->SetShadowOpacity(aLayer->GetOpacity());

  const FrameMetrics* metrics = GetFrameMetrics(aLayer);

  gfx3DMatrix shadowTransform = aLayer->GetTransform();
  ViewTransform layerTransform = aTransform;

  if (metrics && metrics->IsScrollable()) {
    const ViewID scrollId = metrics->mScrollId;
    const nsContentView* view =
      aFrameLoader->GetCurrentRemoteFrame()->GetContentView(scrollId);
    NS_ABORT_IF_FALSE(view, "Array of views should be consistent with layer tree");
    const gfx3DMatrix& currentTransform = aLayer->GetTransform();

    const ViewConfig& config = view->GetViewConfig();
    // With temporary scale we should compensate translation
    // using temporary scale value
    aTempScaleDiffX *= GetXScale(shadowTransform) * config.mXScale;
    aTempScaleDiffY *= GetYScale(shadowTransform) * config.mYScale;
    ViewTransform viewTransform = ComputeShadowTreeTransform(
      aFrame, aFrameLoader, metrics, view->GetViewConfig(),
      aTempScaleDiffX, aTempScaleDiffY
    );

    // Apply the layer's own transform *before* the view transform
    shadowTransform = gfx3DMatrix(viewTransform) * currentTransform;

    layerTransform = viewTransform;
    if (metrics->IsRootScrollable()) {
      // Apply the translation *before* we do the rest of the transforms.
      nsIntPoint offset = GetContentRectLayerOffset(aFrame, aBuilder);
      shadowTransform = shadowTransform *
          gfx3DMatrix::Translation(float(offset.x), float(offset.y), 0.0);
    }
  }

  if (aLayer->GetIsFixedPosition() &&
      !aLayer->GetParent()->GetIsFixedPosition()) {
    // Alter the shadow transform of fixed position layers in the situation
    // that the view transform's scroll position doesn't match the actual
    // scroll position, due to asynchronous layer scrolling.
    float offsetX = layerTransform.mTranslation.x / layerTransform.mXScale;
    float offsetY = layerTransform.mTranslation.y / layerTransform.mYScale;
    ReverseTranslate(shadowTransform, gfxPoint(offsetX, offsetY));
    const nsIntRect* clipRect = shadow->GetShadowClipRect();
    if (clipRect) {
      nsIntRect transformedClipRect(*clipRect);
      transformedClipRect.MoveBy(-offsetX, -offsetY);
      shadow->SetShadowClipRect(&transformedClipRect);
    }
  }

  // The transform already takes the resolution scale into account.  Since we
  // will apply the resolution scale again when computing the effective
  // transform, we must apply the inverse resolution scale here.
  if (ContainerLayer* c = aLayer->AsContainerLayer()) {
    shadowTransform.Scale(1.0f/c->GetPreXScale(),
                          1.0f/c->GetPreYScale(),
                          1);
  }
  shadowTransform.ScalePost(1.0f/aLayer->GetPostXScale(),
                            1.0f/aLayer->GetPostYScale(),
                            1);

  shadow->SetShadowTransform(shadowTransform);
  for (Layer* child = aLayer->GetFirstChild();
       child; child = child->GetNextSibling()) {
    TransformShadowTree(aBuilder, aFrameLoader, aFrame, child, layerTransform,
                        aTempScaleDiffX, aTempScaleDiffY);
  }
}