Fix a translate issue with saveLayer
Bug: 28667141
saveLayer clips the layer to the size it needs to
be and will translate content if necessary, but
the drawLayerOp that results from that was not
translated to handle the shifted draw content.
This fixes that
Change-Id: I3c9ffd5d0282fa1b958bced94c25e9744281e9be
diff --git a/libs/hwui/FrameBuilder.cpp b/libs/hwui/FrameBuilder.cpp
index 746e99a..cb8e55f 100644
--- a/libs/hwui/FrameBuilder.cpp
+++ b/libs/hwui/FrameBuilder.cpp
@@ -878,11 +878,49 @@
restoreForLayer();
+ // saveLayer will clip & translate the draw contents, so we need
+ // to translate the drawLayer by how much the contents was translated
+ // TODO: Unify this with beginLayerOp so we don't have to calculate this
+ // twice
+ uint32_t layerWidth = (uint32_t) beginLayerOp.unmappedBounds.getWidth();
+ uint32_t layerHeight = (uint32_t) beginLayerOp.unmappedBounds.getHeight();
+
+ auto previous = mCanvasState.currentSnapshot();
+ Vector3 lightCenter = previous->getRelativeLightCenter();
+
+ // Combine all transforms used to present saveLayer content:
+ // parent content transform * canvas transform * bounds offset
+ Matrix4 contentTransform(*(previous->transform));
+ contentTransform.multiply(beginLayerOp.localMatrix);
+ contentTransform.translate(beginLayerOp.unmappedBounds.left,
+ beginLayerOp.unmappedBounds.top);
+
+ Matrix4 inverseContentTransform;
+ inverseContentTransform.loadInverse(contentTransform);
+
+ // map the light center into layer-relative space
+ inverseContentTransform.mapPoint3d(lightCenter);
+
+ // Clip bounds of temporary layer to parent's clip rect, so:
+ Rect saveLayerBounds(layerWidth, layerHeight);
+ // 1) transform Rect(width, height) into parent's space
+ // note: left/top offsets put in contentTransform above
+ contentTransform.mapRect(saveLayerBounds);
+ // 2) intersect with parent's clip
+ saveLayerBounds.doIntersect(previous->getRenderTargetClip());
+ // 3) and transform back
+ inverseContentTransform.mapRect(saveLayerBounds);
+ saveLayerBounds.doIntersect(Rect(layerWidth, layerHeight));
+ saveLayerBounds.roundOut();
+
+ Matrix4 localMatrix(beginLayerOp.localMatrix);
+ localMatrix.translate(saveLayerBounds.left, saveLayerBounds.top);
+
// record the draw operation into the previous layer's list of draw commands
// uses state from the associated beginLayerOp, since it has all the state needed for drawing
LayerOp* drawLayerOp = mAllocator.create_trivial<LayerOp>(
beginLayerOp.unmappedBounds,
- beginLayerOp.localMatrix,
+ localMatrix,
beginLayerOp.localClip,
beginLayerOp.paint,
&(mLayerBuilders[finishedLayerIndex]->offscreenBuffer));