cc: Remove separate x/y raster scales.

cc/tiles/picture_layer_tiling.cc

Index: cc/tiles/picture_layer_tiling.cc
diff --git a/cc/tiles/picture_layer_tiling.cc b/cc/tiles/picture_layer_tiling.cc
index 8050a8bdc3d798495cd6f8fb9746689bd73660c3..623ab3edcc4c4ad359ce0303a438783d9e6e46c5 100644
--- a/cc/tiles/picture_layer_tiling.cc
+++ b/cc/tiles/picture_layer_tiling.cc
@@ -29,31 +29,15 @@
 #include "ui/gfx/geometry/size_conversions.h"
 
 namespace cc {
-namespace {
-// The math is similar to gfx::Rect::ManhattanInternalDistance except that each
-// component is scaled by the specified |scale|.
-float ComputeScaledManhattalInternalDistance(const gfx::Rect& a,
-                                             const gfx::Rect& b,
-                                             const gfx::SizeF& scale) {
-  gfx::Rect combined(a);
-  combined.Union(b);
-
-  float x =
-      scale.width() * std::max(0, combined.width() - a.width() - b.width() + 1);
-  float y = scale.height() *
-            std::max(0, combined.height() - a.height() - b.height() + 1);
-  return x + y;
-}
-}  // namespace
 
 PictureLayerTiling::PictureLayerTiling(
     WhichTree tree,
-    const gfx::SizeF& raster_scales,
+    float contents_scale,
     scoped_refptr<RasterSource> raster_source,
     PictureLayerTilingClient* client,
     float min_preraster_distance,
     float max_preraster_distance)
-    : raster_scales_(raster_scales),
+    : contents_scale_(contents_scale),
       client_(client),
       tree_(tree),
       raster_source_(raster_source),
@@ -61,17 +45,14 @@ PictureLayerTiling::PictureLayerTiling(
       max_preraster_distance_(max_preraster_distance) {
   DCHECK(!raster_source->IsSolidColor());
   gfx::Size content_bounds =
-      gfx::ScaleToCeiledSize(raster_source_->GetSize(), raster_scales_.width(),
-                             raster_scales_.height());
+      gfx::ScaleToCeiledSize(raster_source_->GetSize(), contents_scale_);
   gfx::Size tile_size = client_->CalculateTileSize(content_bounds);
 
-  DCHECK(!gfx::ScaleToFlooredSize(raster_source_->GetSize(),
-                                  raster_scales_.width(),
-                                  raster_scales_.height())
+  DCHECK(!gfx::ScaleToFlooredSize(raster_source_->GetSize(), contents_scale_)
               .IsEmpty())
       << "Tiling created with scale too small as contents become empty."
       << " Layer bounds: " << raster_source_->GetSize().ToString()
-      << " Raster scales: " << raster_scales_.ToString();
+      << " Raster scale: " << contents_scale_;
 
   tiling_data_.SetTilingSize(content_bounds);
   tiling_data_.SetMaxTextureSize(tile_size);
@@ -126,8 +107,8 @@ void PictureLayerTiling::CreateMissingTilesInLiveTilesRect() {
           gfx::Rect invalidated;
           for (Region::Iterator iter(*invalidation); iter.has_rect();
                iter.next()) {
-            gfx::Rect invalid_content_rect = gfx::ScaleToEnclosingRect(
-                iter.rect(), raster_scales_.width(), raster_scales_.height());
+            gfx::Rect invalid_content_rect =
+                gfx::ScaleToEnclosingRect(iter.rect(), contents_scale_);
             invalid_content_rect.Intersect(tile_rect);
             invalidated.Union(invalid_content_rect);
           }
@@ -186,8 +167,8 @@ void PictureLayerTiling::SetRasterSourceAndResize(
   gfx::Size old_layer_bounds = raster_source_->GetSize();
   raster_source_ = std::move(raster_source);
   gfx::Size new_layer_bounds = raster_source_->GetSize();
-  gfx::Size content_bounds = gfx::ScaleToCeiledSize(
-      new_layer_bounds, raster_scales_.width(), raster_scales_.height());
+  gfx::Size content_bounds =
+      gfx::ScaleToCeiledSize(new_layer_bounds, contents_scale_);
   gfx::Size tile_size = client_->CalculateTileSize(content_bounds);
 
   if (tile_size != tiling_data_.max_texture_size()) {
@@ -281,8 +262,8 @@ void PictureLayerTiling::RemoveTilesInRegion(const Region& layer_invalidation,
        iter.next()) {
     gfx::Rect layer_rect = iter.rect();
     // The pixels which are invalid in content space.
-    gfx::Rect invalid_content_rect = gfx::ScaleToEnclosingRect(
-        layer_rect, raster_scales_.width(), raster_scales_.height());
+    gfx::Rect invalid_content_rect =
+        gfx::ScaleToEnclosingRect(layer_rect, contents_scale_);
     gfx::Rect coverage_content_rect = invalid_content_rect;
     // Avoid needless work by not bothering to invalidate where there aren't
     // tiles.
@@ -318,10 +299,10 @@ void PictureLayerTiling::RemoveTilesInRegion(const Region& layer_invalidation,
 Tile::CreateInfo PictureLayerTiling::CreateInfoForTile(int i, int j) const {
   gfx::Rect tile_rect = tiling_data_.TileBoundsWithBorder(i, j);
   tile_rect.set_size(tiling_data_.max_texture_size());
-  gfx::Rect enclosing_layer_rect = gfx::ScaleToEnclosingRect(
-      tile_rect, 1.f / raster_scales_.width(), 1.f / raster_scales_.height());
+  gfx::Rect enclosing_layer_rect =
+      gfx::ScaleToEnclosingRect(tile_rect, 1.f / contents_scale_);
   return Tile::CreateInfo(this, i, j, enclosing_layer_rect, tile_rect,
-                          raster_scales_);
+                          contents_scale_);
 }
 
 bool PictureLayerTiling::ShouldCreateTileAt(
@@ -360,8 +341,8 @@ bool PictureLayerTiling::ShouldCreateTileAt(
   // on the active tree and avoid floating point inconsistencies.
   for (Region::Iterator iter(*layer_invalidation); iter.has_rect();
        iter.next()) {
-    gfx::Rect invalid_content_rect = gfx::ScaleToEnclosingRect(
-        iter.rect(), raster_scales_.width(), raster_scales_.height());
+    gfx::Rect invalid_content_rect =
+        gfx::ScaleToEnclosingRect(iter.rect(), contents_scale_);
     if (invalid_content_rect.Intersects(info.content_rect))
       return true;
   }
@@ -395,8 +376,7 @@ PictureLayerTiling::CoverageIterator::CoverageIterator(
   // In order to avoid artifacts in geometry_rect scaling and clamping to ints,
   // the |coverage_scale| should always be at least as big as the tiling's
   // raster scales.
-  DCHECK_GE(coverage_scale, tiling_->raster_scales_.width());
-  DCHECK_GE(coverage_scale, tiling_->raster_scales_.height());
+  DCHECK_GE(coverage_scale, tiling_->contents_scale_);
 
   // Clamp |coverage_rect| to the bounds of this tiling's raster source.
   coverage_rect_max_bounds_ =
@@ -405,9 +385,7 @@ PictureLayerTiling::CoverageIterator::CoverageIterator(
   if (coverage_rect_.IsEmpty())
     return;
 
-  coverage_to_content_scale_ =
-      gfx::SizeF(tiling_->raster_scales_.width() / coverage_scale,
-                 tiling_->raster_scales_.height() / coverage_scale);
+  coverage_to_content_scale_ = tiling_->contents_scale_ / coverage_scale;
 
   // Find the indices of the texel samples that enclose the rect we want to
   // cover.
@@ -425,9 +403,8 @@ PictureLayerTiling::CoverageIterator::CoverageIterator(
   // wanted_texels(sample coordinates) = (l:99.5, t:189.5, r:280.5, b:371.5)
   // Or in integer index:
   // wanted_texels(integer index) = (l:99, t:189, r:280, b:371)
-  gfx::RectF content_rect = gfx::ScaleRect(gfx::RectF(coverage_rect_),
-                                           coverage_to_content_scale_.width(),
-                                           coverage_to_content_scale_.height());
+  gfx::RectF content_rect =
+      gfx::ScaleRect(gfx::RectF(coverage_rect_), coverage_to_content_scale_);
   content_rect.Offset(-0.5f, -0.5f);
   gfx::Rect wanted_texels = gfx::ToEnclosingRect(content_rect);
 
@@ -489,8 +466,7 @@ PictureLayerTiling::CoverageIterator::operator++() {
   // Convert texel_extent to coverage scale, which is what we have to report
   // geometry_rect in.
   current_geometry_rect_ = gfx::ToEnclosedRect(
-      gfx::ScaleRect(texel_extent, 1.f / coverage_to_content_scale_.width(),
-                     1.f / coverage_to_content_scale_.height()));
+      gfx::ScaleRect(texel_extent, 1.f / coverage_to_content_scale_));
   {
     // Adjust external edges to cover the whole layer in dest space.
     //
@@ -555,8 +531,7 @@ gfx::RectF PictureLayerTiling::CoverageIterator::texture_rect() const {
 
   // Convert from dest space => content space => texture space.
   gfx::RectF texture_rect(current_geometry_rect_);
-  texture_rect.Scale(coverage_to_content_scale_.width(),
-                     coverage_to_content_scale_.height());
+  texture_rect.Scale(coverage_to_content_scale_);
   texture_rect.Intersect(gfx::RectF(gfx::SizeF(tiling_->tiling_size())));
   if (texture_rect.IsEmpty())
     return texture_rect;
@@ -602,9 +577,7 @@ void PictureLayerTiling::ComputeTilePriorityRects(
     set_all_tiles_done(false);
   }
 
-  gfx::SizeF content_to_screen_scale(
-      ideal_contents_scale / raster_scales_.width(),
-      ideal_contents_scale / raster_scales_.height());
+  float content_to_screen_scale = ideal_contents_scale / contents_scale_;
 
   const gfx::Rect* input_rects[] = {
       &visible_rect_in_layer_space, &skewport_in_layer_space,
@@ -612,8 +585,7 @@ void PictureLayerTiling::ComputeTilePriorityRects(
   gfx::Rect output_rects[4];
   for (size_t i = 0; i < arraysize(input_rects); ++i) {
     output_rects[i] = gfx::ToEnclosingRect(
-        gfx::ScaleRect(gfx::RectF(*input_rects[i]), raster_scales_.width(),
-                       raster_scales_.height()));
+        gfx::ScaleRect(gfx::RectF(*input_rects[i]), contents_scale_));
   }
   // Make sure the eventually rect is aligned to tile bounds.
   output_rects[3] =
@@ -626,7 +598,7 @@ void PictureLayerTiling::ComputeTilePriorityRects(
 }
 
 void PictureLayerTiling::SetTilePriorityRects(
-    const gfx::SizeF& content_to_screen_scale,
+    float content_to_screen_scale,
     const gfx::Rect& visible_rect_in_content_space,
     const gfx::Rect& skewport,
     const gfx::Rect& soon_border_rect,
@@ -649,15 +621,14 @@ void PictureLayerTiling::SetTilePriorityRects(
   // Note that we use the largest skewport extent from the viewport as the
   // "skewport extent". Also note that this math can't produce negative numbers,
   // since skewport.Contains(visible_rect) is always true.
-  max_skewport_extent_in_screen_space_ = std::max(
-      current_content_to_screen_scale_.width() *
-          std::max(
-              current_visible_rect_.x() - current_skewport_rect_.x(),
-              current_skewport_rect_.right() - current_visible_rect_.right()),
-      current_content_to_screen_scale_.height() *
-          std::max(current_visible_rect_.y() - current_skewport_rect_.y(),
-                   current_skewport_rect_.bottom() -
-                       current_visible_rect_.bottom()));
+  max_skewport_extent_in_screen_space_ =
+      current_content_to_screen_scale_ *
+      std::max(std::max(current_visible_rect_.x() - current_skewport_rect_.x(),
+                        current_skewport_rect_.right() -
+                            current_visible_rect_.right()),
+               std::max(current_visible_rect_.y() - current_skewport_rect_.y(),
+                        current_skewport_rect_.bottom() -
+                            current_visible_rect_.bottom()));
 }
 
 void PictureLayerTiling::SetLiveTilesRect(
@@ -758,10 +729,9 @@ bool PictureLayerTiling::IsTileOccludedOnCurrentTree(const Tile* tile) const {
   if (tile_query_rect.IsEmpty())
     return false;
 
-  if (raster_scales_ != gfx::SizeF(1.f, 1.f)) {
+  if (contents_scale_ != 1.f) {
     tile_query_rect =
-        gfx::ScaleToEnclosingRect(tile_query_rect, 1.f / raster_scales_.width(),
-                                  1.f / raster_scales_.height());
+        gfx::ScaleToEnclosingRect(tile_query_rect, 1.f / contents_scale_);
   }
   return current_occlusion_in_layer_space_.IsOccluded(tile_query_rect);
 }
@@ -843,11 +813,7 @@ PrioritizedTile PictureLayerTiling::MakePrioritizedTile(
     PriorityRectType priority_rect_type) const {
   DCHECK(tile);
   DCHECK(raster_source()->CoversRect(tile->enclosing_layer_rect()))
-      << "Recording rect: "
-      << gfx::ScaleToEnclosingRect(tile->content_rect(),
-                                   1.f / tile->raster_scales().width(),
-                                   1.f / tile->raster_scales().height())
-             .ToString();
+      << "Tile layer rect: " << tile->enclosing_layer_rect().ToString();
 
   const auto& tile_priority = ComputePriorityForTile(tile, priority_rect_type);
   // Note that TileManager will consider this flag but may rasterize the tile
@@ -901,10 +867,10 @@ TilePriority PictureLayerTiling::ComputePriorityForTile(
 
   gfx::Rect tile_bounds =
       tiling_data_.TileBounds(tile->tiling_i_index(), tile->tiling_j_index());
-  DCHECK_GT(current_content_to_screen_scale_.width(), 0.f);
-  DCHECK_GT(current_content_to_screen_scale_.height(), 0.f);
-  float distance_to_visible = ComputeScaledManhattalInternalDistance(
-      current_visible_rect_, tile_bounds, current_content_to_screen_scale_);
+  DCHECK_GT(current_content_to_screen_scale_, 0.f);
+  float distance_to_visible =
+      current_content_to_screen_scale_ *
+      current_visible_rect_.ManhattanInternalDistance(tile_bounds);
 
   return TilePriority(resolution_, priority_bin, distance_to_visible);
 }
@@ -943,13 +909,7 @@ void PictureLayerTiling::GetAllPrioritizedTilesForTracing(
 void PictureLayerTiling::AsValueInto(
     base::trace_event::TracedValue* state) const {
   state->SetInteger("num_tiles", base::saturated_cast<int>(tiles_.size()));
-  // TODO(vmpstr): Change frameviewer to use raster scales.
-  state->SetDouble("content_scale", contents_scale_key());
-
-  state->BeginArray("raster_scales");
-  state->AppendDouble(raster_scales_.width());
-  state->AppendDouble(raster_scales_.height());
-  state->EndArray();
+  state->SetDouble("content_scale", contents_scale());
 
   MathUtil::AddToTracedValue("visible_rect", current_visible_rect_, state);
   MathUtil::AddToTracedValue("skewport_rect", current_skewport_rect_, state);