Make sure frame buffer 0 is bound before calling GL functor

Make sure view port and frame buffer are set to the correct values
before calling GL functor (WebView) draw.
Improve correctness for stencil clip by doing a second flush that
guarantees the stencil clear will be executed after draw commands.

Bug: 79619253
Test: XFINITY Connect app draws correctly
Change-Id: Ieb3d0d70caf0469b6393e6287f8529cd86519301

1 files changed, 8 insertions, 3 deletions

diff --git a/libs/hwui/pipeline/skia/GLFunctorDrawable.cpp b/libs/hwui/pipeline/skia/GLFunctorDrawable.cpp
index 145e3c485cbc..9c80ff86df53 100644
--- a/libs/hwui/pipeline/skia/GLFunctorDrawable.cpp
+++ b/libs/hwui/pipeline/skia/GLFunctorDrawable.cpp
@@ -76,13 +76,20 @@ void GLFunctorDrawable::onDraw(SkCanvas* canvas) {
     // apply a simple clip with a scissor or a complex clip with a stencil
     SkRegion clipRegion;
     canvas->temporary_internal_getRgnClip(&clipRegion);
+    canvas->flush();
+    glBindFramebuffer(GL_FRAMEBUFFER, 0);
+    glViewport(0, 0, info.width, info.height);
     if (CC_UNLIKELY(clipRegion.isComplex())) {
+        //TODO: move stencil clear and canvas flush to SkAndroidFrameworkUtils::clipWithStencil
         glDisable(GL_SCISSOR_TEST);
         glStencilMask(0x1);
         glClearStencil(0);
         glClear(GL_STENCIL_BUFFER_BIT);
+        // GL ops get inserted here if previous flush is missing, which could dirty the stencil
         bool stencilWritten = SkAndroidFrameworkUtils::clipWithStencil(canvas);
-        canvas->flush();
+        canvas->flush(); //need this flush for the single op that draws into the stencil
+        glBindFramebuffer(GL_FRAMEBUFFER, 0);
+        glViewport(0, 0, info.width, info.height);
         if (stencilWritten) {
             glStencilMask(0x1);
             glStencilFunc(GL_EQUAL, 0x1, 0x1);
@@ -93,11 +100,9 @@ void GLFunctorDrawable::onDraw(SkCanvas* canvas) {
             glDisable(GL_STENCIL_TEST);
         }
     } else if (clipRegion.isEmpty()) {
-        canvas->flush();
         glDisable(GL_STENCIL_TEST);
         glDisable(GL_SCISSOR_TEST);
     } else {
-        canvas->flush();
         glDisable(GL_STENCIL_TEST);
         glEnable(GL_SCISSOR_TEST);
         setScissor(info.height, clipRegion.getBounds());