cc: Expand invalidation to full tile when recording is missing for the tile.

cc/resources/picture_pile.cc

 // Copyright 2012 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 "cc/resources/picture_pile.h"
 
 #include <algorithm>
 #include <limits>
 #include <vector>
 
@@ skipping 128 matching lines @@
 
 }  // namespace
 
 namespace cc {
 
 PicturePile::PicturePile() : is_suitable_for_gpu_rasterization_(true) {}
 
 PicturePile::~PicturePile() {
 }
 
-bool PicturePile::Update(ContentLayerClient* painter,
-                         SkColor background_color,
-                         bool contents_opaque,
-                         bool contents_fill_bounds_completely,
-                         const Region& invalidation,
-                         const gfx::Rect& visible_layer_rect,
-                         int frame_number,
-                         Picture::RecordingMode recording_mode,
-                         RenderingStatsInstrumentation* stats_instrumentation) {
+bool PicturePile::UpdateAndExpandInvalidation(
+    ContentLayerClient* painter,
+    Region* invalidation,
+    SkColor background_color,
+    bool contents_opaque,
+    bool contents_fill_bounds_completely,
+    const gfx::Rect& visible_layer_rect,
+    int frame_number,
+    Picture::RecordingMode recording_mode,
+    RenderingStatsInstrumentation* stats_instrumentation) {
   background_color_ = background_color;
   contents_opaque_ = contents_opaque;
   contents_fill_bounds_completely_ = contents_fill_bounds_completely;
 
   gfx::Rect interest_rect = visible_layer_rect;
   interest_rect.Inset(
       -kPixelDistanceToRecord,
       -kPixelDistanceToRecord,
       -kPixelDistanceToRecord,
       -kPixelDistanceToRecord);
   recorded_viewport_ = interest_rect;
   recorded_viewport_.Intersect(tiling_rect());
 
+  Region invalidation_expanded_to_recording_tiles;
+
   bool invalidated = false;
-  for (Region::Iterator i(invalidation); i.has_rect(); i.next()) {
-    gfx::Rect invalidation = i.rect();
+  for (Region::Iterator i(*invalidation); i.has_rect(); i.next()) {
+    gfx::Rect invalid_rect = i.rect();
     // Split this inflated invalidation across tile boundaries and apply it
     // to all tiles that it touches.
     bool include_borders = true;
-    for (TilingData::Iterator iter(&tiling_, invalidation, include_borders);
+    for (TilingData::Iterator iter(&tiling_, invalid_rect, include_borders);
          iter;
          ++iter) {
       const PictureMapKey& key = iter.index();
 
       PictureMap::iterator picture_it = picture_map_.find(key);
       if (picture_it == picture_map_.end())
         continue;
 
       // Inform the grid cell that it has been invalidated in this frame.
       invalidated = picture_it->second.Invalidate(frame_number) || invalidated;
     }
+
+    int left_tile = tiling_.FirstBorderTileXIndexFromSrcCoord(invalid_rect.x());
+    int top_tile = tiling_.FirstBorderTileYIndexFromSrcCoord(invalid_rect.y());
+    int right_tile =
+        tiling_.LastBorderTileXIndexFromSrcCoord(invalid_rect.right() - 1);
+    int bottom_tile =
+        tiling_.LastBorderTileYIndexFromSrcCoord(invalid_rect.bottom() - 1);
+    gfx::Rect invalid_rect_filling_tiles =
+        gfx::UnionRects(tiling_.TileBoundsWithBorder(left_tile, top_tile),

[enne (OOO), 2014/06/13 22:26:42]

I think
invalidation_expanded_to_recording_tiles.Union(ExpandRectToTileBoundsWithBorders(invalid_rect))
will do what you're doing here.

However, the previous code didn't include borders, so I'm wondering if this will
overinvalidate.  I think this should just be TileBounds.

Here's the example I'm thinking of.  Say you have three recording tiles |A|B|C|.
 There's an invalidation that's on the edge of C, but B's border overlaps.  So
this code here will say invalid_rect_filling_tiles = union(B,C).  If you include
B and C's border in that rect, then on the compositor thread when we toss tiles
that intersect invalidations we will also toss tiles that could be entirely
rastered by A because they are hit by B's borders.

[enne (OOO), 2014/06/13 22:34:13]

Actually, more importantly, you should only inflate rects for tiles that are not
rerecorded.  So, this logic needs to move into the for loop below.

+                        tiling_.TileBoundsWithBorder(right_tile, bottom_tile));
+    invalidation_expanded_to_recording_tiles.Union(invalid_rect_filling_tiles);
   }
 
+  // Return the expanded invalidation.
+  invalidation_expanded_to_recording_tiles.Swap(invalidation);
+
   // Make a list of all invalid tiles; we will attempt to
   // cluster these into multiple invalidation regions.
   std::vector<gfx::Rect> invalid_tiles;
   bool include_borders = true;
   for (TilingData::Iterator it(&tiling_, interest_rect, include_borders); it;
        ++it) {
     const PictureMapKey& key = it.index();
     PictureInfo& info = picture_map_[key];
 
     gfx::Rect rect = PaddedRect(key);
@@ skipping 76 matching lines @@
     }
     DCHECK(found_tile_for_recorded_picture);
   }
 
   has_any_recordings_ = true;
   DCHECK(CanRasterSlowTileCheck(recorded_viewport_));
   return true;
 }
 
 }  // namespace cc