Refactor OverlayStrategySandwich and OverlayStrategyCommon

cc/output/overlay_strategy_single_on_top.cc

Index: cc/output/overlay_strategy_single_on_top.cc
diff --git a/cc/output/overlay_strategy_single_on_top.cc b/cc/output/overlay_strategy_single_on_top.cc
index 6b63045c0154c0218baa9bd5704ff52d4db0ddca..d08da5cd31452a8409f9f2d9f5ced28717ce25f9 100644
--- a/cc/output/overlay_strategy_single_on_top.cc
+++ b/cc/output/overlay_strategy_single_on_top.cc
@@ -4,34 +4,48 @@
 
 #include "cc/output/overlay_strategy_single_on_top.h"
 
-#include <limits>
-
 #include "cc/base/math_util.h"
 #include "cc/output/overlay_candidate_validator.h"
 #include "cc/quads/draw_quad.h"
 
 namespace cc {
 
+OverlayStrategySingleOnTop::OverlayStrategySingleOnTop(
+    OverlayCandidateValidator* capability_checker)
+    : capability_checker_(capability_checker) {
+  DCHECK(capability_checker);
+}
+
 OverlayStrategySingleOnTop::~OverlayStrategySingleOnTop() {}
 
-OverlayResult OverlayStrategySingleOnTop::TryOverlay(
-    OverlayCandidateValidator* capability_checker,
-    RenderPassList* render_passes_in_draw_order,
+bool OverlayStrategySingleOnTop::Attempt(RenderPassList* render_passes,
+                                         OverlayCandidateList* candidate_list) {
+  QuadList& quad_list = render_passes->back()->quad_list;

[ccameron, 2015/10/05 19:28:29]

Just out of curiosity, any reason you didn't inline TryOverlay here (but did in
Underlay strategy)? I sort-of like the more compact inlined version, FWIW.

[Andre, 2015/10/05 20:24:20]

To inline, the "return false" in line 48 needs to become "continue" for the
outer for loop (line 24), so it became messy.

+  for (auto it = quad_list.begin(); it != quad_list.end(); ++it) {
+    OverlayCandidate candidate;
+    if (OverlayCandidate::FromDrawQuad(*it, &candidate) &&
+        TryOverlay(quad_list, candidate_list, candidate, it)) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool OverlayStrategySingleOnTop::TryOverlay(
+    QuadList& quad_list,
     OverlayCandidateList* candidate_list,
     const OverlayCandidate& candidate,
-    QuadList::Iterator* candidate_iterator,
-    float device_scale_factor) {
-  RenderPass* root_render_pass = render_passes_in_draw_order->back();
-  QuadList& quad_list = root_render_pass->quad_list;
+    QuadList::Iterator candidate_iterator) {
   // Check that no prior quads overlap it.
   for (auto overlap_iter = quad_list.cbegin();
-       overlap_iter != *candidate_iterator; ++overlap_iter) {
+       overlap_iter != candidate_iterator; ++overlap_iter) {
     gfx::RectF overlap_rect = MathUtil::MapClippedRect(
         overlap_iter->shared_quad_state->quad_to_target_transform,
         gfx::RectF(overlap_iter->rect));
     if (candidate.display_rect.Intersects(overlap_rect) &&
-        !OverlayStrategyCommon::IsInvisibleQuad(*overlap_iter))
-      return DID_NOT_CREATE_OVERLAY;
+        !OverlayCandidate::IsInvisibleQuad(*overlap_iter))
+      return false;
   }
 
   // Add the overlay.
@@ -40,16 +54,16 @@ OverlayResult OverlayStrategySingleOnTop::TryOverlay(
   new_candidate_list.back().plane_z_order = 1;
 
   // Check for support.
-  capability_checker->CheckOverlaySupport(&new_candidate_list);
+  capability_checker_->CheckOverlaySupport(&new_candidate_list);
 
   // If the candidate can be handled by an overlay, create a pass for it.
   if (new_candidate_list.back().overlay_handled) {
-    quad_list.EraseAndInvalidateAllPointers(*candidate_iterator);
+    quad_list.EraseAndInvalidateAllPointers(candidate_iterator);
     candidate_list->swap(new_candidate_list);
-    return CREATED_OVERLAY_STOP_LOOKING;
+    return true;
   }
 
-  return DID_NOT_CREATE_OVERLAY;
+  return false;
 }
 
 }  // namespace cc