aw: Ensure invalidation when pipeline is stalled

android_webview/browser/browser_view_renderer.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "android_webview/browser/browser_view_renderer.h"
 
 #include "android_webview/browser/browser_view_renderer_client.h"
 #include "android_webview/browser/shared_renderer_state.h"
 #include "android_webview/common/aw_switches.h"
 #include "base/auto_reset.h"
@@ skipping 67 matching lines @@
       is_paused_(false),
       view_visible_(false),
       window_visible_(false),
       attached_to_window_(false),
       hardware_enabled_(false),
       dip_scale_(0.0),
       page_scale_factor_(1.0),
       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),
       height_(0) {
   CHECK(web_contents_);
   content::SynchronousCompositor::SetClientForWebContents(web_contents_, this);
 
   // Currently the logic in this class relies on |compositor_| remaining
   // NULL until the DidInitializeCompositor() call, hence it is not set here.
 }
@@ skipping 106 matching lines @@
   // Perform a software draw
   return OnDrawSoftware(java_canvas);
 }
 
 bool BrowserViewRenderer::OnDrawHardware(jobject java_canvas) {
   TRACE_EVENT0("android_webview", "BrowserViewRenderer::OnDrawHardware");
   if (!compositor_)
     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();
     if (hardware_enabled_) {
       tile_manager_key_ = GlobalTileManager::GetInstance()->PushBack(this);
     }
   }
   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",
                          "EarlyOut_PreviousFrameUnconsumed",
                          TRACE_EVENT_SCOPE_THREAD);
     SkippedCompositeInDraw();
     return client_->RequestDrawGL(java_canvas, false);
   }
 
   scoped_ptr<cc::CompositorFrame> frame = CompositeHw();
@@ skipping 14 matching lines @@
   gfx::Size surface_size(width_, height_);
   gfx::Rect viewport(surface_size);
   gfx::Rect clip = viewport;
   gfx::Transform transform_for_tile_priority =
       parent_draw_constraints_.transform;
 
   // If the WebView is on a layer, WebView does not know what transform is
   // 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,
                                 gfx::Transform(),
                                 viewport,
                                 clip,
                                 viewport_rect_for_tile_priority,
                                 transform_for_tile_priority);
   if (frame.get())
     DidComposite();
@@ skipping 24 matching lines @@
 }
 
 void BrowserViewRenderer::ReturnResourceFromParent() {
   cc::CompositorFrameAck frame_ack;
   shared_renderer_state_->SwapReturnedResources(&frame_ack.resources);
   if (compositor_ && !frame_ack.resources.empty()) {
     compositor_->ReturnResources(frame_ack);
   }
 }
 
+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(
         "android_webview", "EarlyOut_NoCompositor", TRACE_EVENT_SCOPE_THREAD);
     return false;
   }
 
   // TODO(hush): right now webview size is passed in as the auxiliary bitmap
   // size, which might hurt performace (only for software draws with auxiliary
   // bitmap). For better performance, get global visible rect, transform it
@@ skipping 326 matching lines @@
   gfx::Vector2d rounded_overscroll_delta = gfx::ToRoundedVector2d(
       scaled_overscroll_delta + overscroll_rounding_error_);
   overscroll_rounding_error_ =
       scaled_overscroll_delta - rounded_overscroll_delta;
   client_->DidOverscroll(rounded_overscroll_delta);
 }
 
 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();
 
   // Stop fallback ticks when one of these is true.
   // 1) Webview is paused. Also need to check we are not in clear view since
   // paused, offscreen still expect clear view to recover.
   // 2) If we are attached to window and the window is not visible (eg when
   // app is in the background). We are sure in this case the webview is used
   // "on-screen" but that updates are not needed when in the background.
@@ skipping 84 matching lines @@
 void BrowserViewRenderer::DidComposite() {
   block_invalidates_ = false;
   post_fallback_tick_.Cancel();
   fallback_tick_fired_.Cancel();
   fallback_tick_pending_ = false;
   EnsureContinuousInvalidation(false, false);
 }
 
 void BrowserViewRenderer::SkippedCompositeInDraw() {
   block_invalidates_ = false;
-  EnsureContinuousInvalidation(false, true);
+  EnsureContinuousInvalidation(true, true);
 }
 
 std::string BrowserViewRenderer::ToString() const {
   std::string str;
   base::StringAppendF(&str, "is_paused: %d ", is_paused_);
   base::StringAppendF(&str, "view_visible: %d ", view_visible_);
   base::StringAppendF(&str, "window_visible: %d ", window_visible_);
   base::StringAppendF(&str, "dip_scale: %f ", dip_scale_);
   base::StringAppendF(&str, "page_scale_factor: %f ", page_scale_factor_);
   base::StringAppendF(&str,
@@ skipping 10 matching lines @@
   base::StringAppendF(&str,
                       "overscroll_rounding_error_: %s ",
                       overscroll_rounding_error_.ToString().c_str());
   base::StringAppendF(
       &str, "on_new_picture_enable: %d ", on_new_picture_enable_);
   base::StringAppendF(&str, "clear_view: %d ", clear_view_);
   return str;
 }
 
 }  // namespace android_webview