Fix T-junctions in layers' generated meshes

bug:4128442

Currently we fix T-junctions for hardware layers, and for
Canvas.saveLayer if the transform isn't rectAsRect. Ideally, hardware
layers should lazily re-generate T-junction free geometry if the
transform becomes non-rectAsRect

Depends on frameworks/native change:
https://googleplex-android-review.googlesource.com/#/c/277668/
which adds Region::createTJunctionFreeRegion()

Change-Id: Ice75b4a1a4459ff835059ea81d70f7d1563fd96d

1 files changed, 8 insertions, 1 deletions

diff --git a/libs/hwui/OpenGLRenderer.cpp b/libs/hwui/OpenGLRenderer.cpp
index 34d1c983f87d..eec5f5fa1a80 100644
--- a/libs/hwui/OpenGLRenderer.cpp
+++ b/libs/hwui/OpenGLRenderer.cpp
@@ -1022,7 +1022,14 @@ void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
     //       information about this implementation
     if (CC_LIKELY(!layer->region.isEmpty())) {
         size_t count;
-        const android::Rect* rects = layer->region.getArray(&count);
+        const android::Rect* rects;
+        Region safeRegion;
+        if (CC_LIKELY(hasRectToRectTransform())) {
+            rects = layer->region.getArray(&count);
+        } else {
+            safeRegion = Region::createTJunctionFreeRegion(layer->region);
+            rects = safeRegion.getArray(&count);
+        }
 
         const float alpha = layer->getAlpha() / 255.0f;
         const float texX = 1.0f / float(layer->getWidth());