Fix garbage showing up beneath dialogs

bug:17463894

Fixes the setViewport method to immediately affect the return values
of getViewportWidth/Height methods.

Also works around tiling extension issues observed on first frame
after window resize by disabling tiling for that frame.

Change-Id: Ie172d572d20d74a1be9cc58ad389af2cffa0e4b6

4 files changed, 15 insertions, 2 deletions

diff --git a/libs/hwui/OpenGLRenderer.cpp b/libs/hwui/OpenGLRenderer.cpp
index 25ea729..ce1d09f 100755
--- a/libs/hwui/OpenGLRenderer.cpp
+++ b/libs/hwui/OpenGLRenderer.cpp
@@ -134,6 +134,8 @@ OpenGLRenderer::OpenGLRenderer(RenderState& renderState)
         , mExtensions(Extensions::getInstance())
         , mRenderState(renderState)
         , mScissorOptimizationDisabled(false)
+        , mSuppressTiling(false)
+        , mFirstFrameAfterResize(true)
         , mCountOverdraw(false)
         , mLightCenter((Vector3){FLT_MIN, FLT_MIN, FLT_MIN})
         , mLightRadius(FLT_MIN)
@@ -179,6 +181,7 @@ void OpenGLRenderer::onViewportInitialized() {
     glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
 
     glEnableVertexAttribArray(Program::kBindingPosition);
+    mFirstFrameAfterResize = true;
 }
 
 void OpenGLRenderer::setupFrameState(float left, float top,
@@ -202,7 +205,9 @@ status_t OpenGLRenderer::startFrame() {
     // Functors break the tiling extension in pretty spectacular ways
     // This ensures we don't use tiling when a functor is going to be
     // invoked during the frame
-    mSuppressTiling = mCaches.hasRegisteredFunctors();
+    mSuppressTiling = mCaches.hasRegisteredFunctors()
+            || mFirstFrameAfterResize;
+    mFirstFrameAfterResize = false;
 
     startTilingCurrentClip(true);
 
diff --git a/libs/hwui/OpenGLRenderer.h b/libs/hwui/OpenGLRenderer.h
index e295b1a..47ef1a9 100755
--- a/libs/hwui/OpenGLRenderer.h
+++ b/libs/hwui/OpenGLRenderer.h
@@ -1013,6 +1013,7 @@ private:
 
     // No-ops start/endTiling when set
     bool mSuppressTiling;
+    bool mFirstFrameAfterResize;
 
     // If true, this renderer will setup drawing to emulate
     // an increment stencil buffer in the color buffer
diff --git a/libs/hwui/StatefulBaseRenderer.cpp b/libs/hwui/StatefulBaseRenderer.cpp
index 12b8c8d..88d6f68 100644
--- a/libs/hwui/StatefulBaseRenderer.cpp
+++ b/libs/hwui/StatefulBaseRenderer.cpp
@@ -49,6 +49,13 @@ void StatefulBaseRenderer::setViewport(int width, int height) {
     mHeight = height;
     mFirstSnapshot->initializeViewport(width, height);
     onViewportInitialized();
+
+    // create a temporary 1st snapshot, so old snapshots are released,
+    // and viewport can be queried safely.
+    // TODO: remove, combine viewport + save stack initialization
+    mSnapshot = new Snapshot(mFirstSnapshot,
+            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
+    mSaveCount = 1;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
diff --git a/libs/hwui/renderthread/CanvasContext.cpp b/libs/hwui/renderthread/CanvasContext.cpp
index 5e6796c..56ec797 100644
--- a/libs/hwui/renderthread/CanvasContext.cpp
+++ b/libs/hwui/renderthread/CanvasContext.cpp
@@ -117,10 +117,10 @@ void CanvasContext::pauseSurface(ANativeWindow* window) {
     stopDrawing();
 }
 
+// TODO: don't pass viewport size, it's automatic via EGL
 void CanvasContext::setup(int width, int height, const Vector3& lightCenter, float lightRadius,
         uint8_t ambientShadowAlpha, uint8_t spotShadowAlpha) {
     if (!mCanvas) return;
-    mCanvas->setViewport(width, height);
     mCanvas->initLight(lightCenter, lightRadius, ambientShadowAlpha, spotShadowAlpha);
 }