// 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);
}
}
// Use shadow layer tree to build display list for the browser's frame.
static void
BuildListForLayer(Layer* aLayer,
nsFrameLoader* aRootFrameLoader,
const gfx3DMatrix& aTransform,
nsDisplayListBuilder* aBuilder,
nsDisplayList& aShadowTree,
nsIFrame* aSubdocFrame)
{
const FrameMetrics* metrics = GetFrameMetrics(aLayer);
gfx3DMatrix transform;
if (metrics && metrics->IsScrollable()) {
const ViewID scrollId = metrics->mScrollId;
// We need to figure out the bounds of the scrollable region using the
// shadow layer tree from the remote process. The metrics viewport is
// defined based on all the transformations of its parent layers and
// the scale of the current layer.
// Calculate transform for this layer.
nsContentView* view =
aRootFrameLoader->GetCurrentRemoteFrame()->GetContentView(scrollId);
// XXX why don't we include aLayer->GetTransform() in the inverse-scale here?
// This seems wrong, but it doesn't seem to cause bugs!
gfx3DMatrix applyTransform = ComputeShadowTreeTransform(
aSubdocFrame, aRootFrameLoader, metrics, view->GetViewConfig(),
1 / GetXScale(aTransform), 1 / GetYScale(aTransform));
transform = applyTransform * aLayer->GetTransform() * aTransform;
// As mentioned above, bounds calculation also depends on the scale
// of this layer.
gfx3DMatrix tmpTransform = aTransform;
Scale(tmpTransform, GetXScale(applyTransform), GetYScale(applyTransform));
// Calculate rect for this layer based on aTransform.
nsRect bounds;
{
nscoord auPerDevPixel = aSubdocFrame->PresContext()->AppUnitsPerDevPixel();
bounds = metrics->mViewport.ToAppUnits(auPerDevPixel);
ApplyTransform(bounds, tmpTransform, auPerDevPixel);
}
aShadowTree.AppendToTop(
new (aBuilder) nsDisplayRemoteShadow(aBuilder, aSubdocFrame, bounds, scrollId));
} else {
transform = aLayer->GetTransform() * aTransform;
}
for (Layer* child = aLayer->GetFirstChild(); child;
child = child->GetNextSibling()) {
BuildListForLayer(child, aRootFrameLoader, transform,
aBuilder, aShadowTree, aSubdocFrame);
}
}
