aw: Ensure invalidation when pipeline is stalled

android_webview/browser/browser_view_renderer.cc

Index: android_webview/browser/browser_view_renderer.cc
diff --git a/android_webview/browser/browser_view_renderer.cc b/android_webview/browser/browser_view_renderer.cc
index be3e162e70dc62ced2937e25eb82588e73f3501c..c90bf37ea0217df2d941cc5aa5dc4fe9ceb2f5d9 100644
--- a/android_webview/browser/browser_view_renderer.cc
+++ b/android_webview/browser/browser_view_renderer.cc
@@ -85,6 +85,7 @@ BrowserViewRenderer::BrowserViewRenderer(
       on_new_picture_enable_(false),
       clear_view_(false),
       compositor_needs_continuous_invalidate_(false),
+      invalidate_after_composite_(false),
       block_invalidates_(false),
       fallback_tick_pending_(false),
       width_(0),
@@ -211,13 +212,6 @@ bool BrowserViewRenderer::OnDrawHardware(jobject java_canvas) {
     return false;
 
   shared_renderer_state_->SetScrollOffset(last_on_draw_scroll_offset_);
-  if (last_on_draw_global_visible_rect_.IsEmpty()) {
-    TRACE_EVENT_INSTANT0("android_webview",
-                         "EarlyOut_EmptyVisibleRect",
-                         TRACE_EVENT_SCOPE_THREAD);
-    shared_renderer_state_->SetForceInvalidateOnNextDrawGL(true);
-    return client_->RequestDrawGL(java_canvas, false);
-  }
 
   if (!hardware_enabled_) {
     hardware_enabled_ = compositor_->InitializeHwDraw();
@@ -228,6 +222,15 @@ bool BrowserViewRenderer::OnDrawHardware(jobject java_canvas) {
   if (!hardware_enabled_)
     return false;
 
+  if (last_on_draw_global_visible_rect_.IsEmpty() &&
+      parent_draw_constraints_.surface_rect.IsEmpty()) {
+    TRACE_EVENT_INSTANT0("android_webview",
+                         "EarlyOut_EmptyVisibleRect",
+                         TRACE_EVENT_SCOPE_THREAD);
+    shared_renderer_state_->SetForceInvalidateOnNextDrawGL(true);
+    return client_->RequestDrawGL(java_canvas, false);
+  }
+
   ReturnResourceFromParent();
   if (shared_renderer_state_->HasCompositorFrame()) {
     TRACE_EVENT_INSTANT0("android_webview",
@@ -262,10 +265,12 @@ scoped_ptr<cc::CompositorFrame> BrowserViewRenderer::CompositeHw() {
   // applied onto the layer so global visible rect does not make sense here.
   // In this case, just use the surface rect for tiling.
   gfx::Rect viewport_rect_for_tile_priority;
-  if (parent_draw_constraints_.is_layer)
+  if (parent_draw_constraints_.is_layer ||
+      last_on_draw_global_visible_rect_.IsEmpty()) {
     viewport_rect_for_tile_priority = parent_draw_constraints_.surface_rect;
-  else
+  } else {
     viewport_rect_for_tile_priority = last_on_draw_global_visible_rect_;
+  }
 
   scoped_ptr<cc::CompositorFrame> frame =
       compositor_->DemandDrawHw(surface_size,
@@ -310,6 +315,11 @@ void BrowserViewRenderer::ReturnResourceFromParent() {
   }
 }
 
+void BrowserViewRenderer::DidSkipCommitFrame() {
+  // Need to keep invalidating until pipelien is no longer stalled.

[hush (inactive), 2014/10/21 01:47:21]

typo: pipeline

also, can you put this function together with "SkippedCompositeInDraw"? They are
very similiar.
Maybe rename them to the same pattern as well, like "DidSkipCommitFrame" and
"DidSkipCompositeInDraw"

+  EnsureContinuousInvalidation(true, false);

[hush (inactive), 2014/10/21 01:47:21]

Just to make sure I am understanding this correctly:
EnsureContinuousInvalidation wouldn't call PostInvalidate if block_invalidates
is true, which means a fallback tick is scheduled but not fired yet. This
fallback tick must be a real, hardware-accelerated fallback tick, because a fake
software fallback tick may not work. Since this function is called from the
parent compositor, we're guaranteed that at this point, the scheduled fallback
tick is the hardware accelerated one?

Actually, is it possible that the scheduled fallback tick is still a software
one at this point?

[boliu, 2014/10/21 02:03:59]

Yes
Mode shouldn't matter imo.
Yeah if a trim comes in.

+}
+
 bool BrowserViewRenderer::OnDrawSoftware(jobject java_canvas) {
   if (!compositor_) {
     TRACE_EVENT_INSTANT0(
@@ -656,12 +666,18 @@ void BrowserViewRenderer::DidOverscroll(gfx::Vector2dF accumulated_overscroll,
 void BrowserViewRenderer::EnsureContinuousInvalidation(
     bool force_invalidate,
     bool skip_reschedule_tick) {
+  if (force_invalidate)
+    invalidate_after_composite_ = true;
+
   // This method should be called again when any of these conditions change.
   bool need_invalidate =
-      compositor_needs_continuous_invalidate_ || force_invalidate;
+      compositor_needs_continuous_invalidate_ || invalidate_after_composite_;
   if (!need_invalidate || block_invalidates_)
     return;
 
+  if (!compositor_needs_continuous_invalidate_ && invalidate_after_composite_)
+    invalidate_after_composite_ = false;
+
   // Always call view invalidate. We rely the Android framework to ignore the
   // invalidate when it's not needed such as when view is not visible.
   client_->PostInvalidate();
@@ -766,7 +782,7 @@ void BrowserViewRenderer::DidComposite() {
 
 void BrowserViewRenderer::SkippedCompositeInDraw() {
   block_invalidates_ = false;
-  EnsureContinuousInvalidation(false, true);
+  EnsureContinuousInvalidation(true, true);
 }
 
 std::string BrowserViewRenderer::ToString() const {