Mark layers that can use LCD text based on layer transform and opacity.

cc/layer_tree_settings.cc

 // Copyright 2011 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/layer_tree_settings.h"
 
 #include <limits>
 
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/string_number_conversions.h"
 #include "cc/switches.h"
 
 namespace cc {
 
 LayerTreeSettings::LayerTreeSettings()
     : acceleratePainting(false)
     , implSidePainting(false)
     , renderVSyncEnabled(true)
     , perTilePaintingEnabled(false)
     , partialSwapEnabled(false)
     , acceleratedAnimationEnabled(true)
     , pageScalePinchZoomEnabled(false)
     , backgroundColorInsteadOfCheckerboard(false)
     , showOverdrawInTracing(false)
+    , canUseLCDText(true)
     , refreshRate(0)
     , maxPartialTextureUpdates(std::numeric_limits<size_t>::max())
     , numRasterThreads(1)
     , defaultTileSize(gfx::Size(256, 256))
     , maxUntiledLayerSize(gfx::Size(512, 512))
     , minimumOcclusionTrackingSize(gfx::Size(160, 160))
 {
     // TODO(danakj): Move this to chromium when we don't go through the WebKit API anymore.
     implSidePainting = CommandLine::ForCurrentProcess()->HasSwitch(cc::switches::kEnableImplSidePainting);
     partialSwapEnabled = CommandLine::ForCurrentProcess()->HasSwitch(switches::kEnablePartialSwap);
     backgroundColorInsteadOfCheckerboard = CommandLine::ForCurrentProcess()->HasSwitch(switches::kBackgroundColorInsteadOfCheckerboard);
     showOverdrawInTracing = CommandLine::ForCurrentProcess()->HasSwitch(switches::kTraceOverdraw);
 
+// TODO(alokp): Remove this hard-coded setting.
+// Platforms that need to disable LCD text must explicitly set this value.
+#if defined(OS_ANDROID)
+    canUseLCDText = false;
+#endif
+
     initialDebugState.showPropertyChangedRects = CommandLine::ForCurrentProcess()->HasSwitch(cc::switches::kShowPropertyChangedRects);
     initialDebugState.showSurfaceDamageRects = CommandLine::ForCurrentProcess()->HasSwitch(cc::switches::kShowSurfaceDamageRects);
     initialDebugState.showScreenSpaceRects = CommandLine::ForCurrentProcess()->HasSwitch(cc::switches::kShowScreenSpaceRects);
     initialDebugState.showReplicaScreenSpaceRects = CommandLine::ForCurrentProcess()->HasSwitch(cc::switches::kShowReplicaScreenSpaceRects);
     initialDebugState.showOccludingRects = CommandLine::ForCurrentProcess()->HasSwitch(cc::switches::kShowOccludingRects);
     initialDebugState.showNonOccludingRects = CommandLine::ForCurrentProcess()->HasSwitch(cc::switches::kShowNonOccludingRects);
 
     if (CommandLine::ForCurrentProcess()->HasSwitch(
             switches::kNumRasterThreads)) {
         const size_t kMaxRasterThreads = 64;
         std::string num_raster_threads =
             CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
                 switches::kNumRasterThreads);
         int num_threads;
         if (base::StringToInt(num_raster_threads, &num_threads) &&
             num_threads > 0 && num_threads <= kMaxRasterThreads) {
             numRasterThreads = num_threads;
         } else {
             LOG(WARNING) << "Bad number of raster threads: " <<
                 num_raster_threads;
         }
     }
 }
 
 LayerTreeSettings::~LayerTreeSettings()
 {
 }
 
 }  // namespace cc