Stop displaying layers with non-invertible transforms.

cc/layers/layer_impl.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/layers/layer_impl.h"
 
 #include "base/debug/trace_event.h"
 #include "base/json/json_reader.h"
 #include "base/strings/stringprintf.h"
 #include "cc/animation/animation_registrar.h"
@@ skipping 44 matching lines @@
       should_flatten_transform_(true),
       layer_property_changed_(false),
       masks_to_bounds_(false),
       contents_opaque_(false),
       is_root_for_isolated_group_(false),
       use_parent_backface_visibility_(false),
       draw_checkerboard_for_missing_tiles_(false),
       draws_content_(false),
       hide_layer_and_subtree_(false),
       force_render_surface_(false),
+      transform_is_invertible_(true),
       is_container_for_fixed_position_layers_(false),
       is_3d_sorted_(false),
       background_color_(0),
       opacity_(1.0),
       blend_mode_(SkXfermode::kSrcOver_Mode),
       draw_depth_(0.f),
       needs_push_properties_(false),
       num_dependents_need_push_properties_(0),
       current_draw_mode_(DRAW_MODE_NONE) {
   DCHECK_GT(layer_id_, 0);
@@ skipping 435 matching lines @@
   layer->SetOpacity(opacity_);
   layer->SetBlendMode(blend_mode_);
   layer->SetIsRootForIsolatedGroup(is_root_for_isolated_group_);
   layer->SetPosition(position_);
   layer->SetIsContainerForFixedPositionLayers(
       is_container_for_fixed_position_layers_);
   layer->SetPositionConstraint(position_constraint_);
   layer->SetShouldFlattenTransform(should_flatten_transform_);
   layer->SetIs3dSorted(is_3d_sorted_);
   layer->SetUseParentBackfaceVisibility(use_parent_backface_visibility_);
-  layer->SetTransform(transform_);
+  layer->SetTransformAndInvertibility(transform_, transform_is_invertible_);
 
   layer->SetScrollClipLayer(scroll_clip_layer_ ? scroll_clip_layer_->id()
                                                : Layer::INVALID_ID);
   layer->set_user_scrollable_horizontal(user_scrollable_horizontal_);
   layer->set_user_scrollable_vertical(user_scrollable_vertical_);
   layer->SetScrollOffsetAndDelta(
       scroll_offset_, layer->ScrollDelta() - layer->sent_scroll_delta());
   layer->SetSentScrollDelta(gfx::Vector2d());
 
   LayerImpl* scroll_parent = NULL;
@@ skipping 457 matching lines @@
 
   is_3d_sorted_ = sorted;
   NoteLayerPropertyChangedForSubtree();
 }
 
 void LayerImpl::SetTransform(const gfx::Transform& transform) {
   if (transform_ == transform)
     return;
 
   transform_ = transform;
+  transform_is_invertible_ = transform_.IsInvertible();
   NoteLayerPropertyChangedForSubtree();
 }
 
+void LayerImpl::SetTransformAndInvertibility(const gfx::Transform& transform,
+                                             bool transform_is_invertible) {
+  if (transform_ == transform) {
+    if (transform_is_invertible_ != transform_is_invertible) {
+      DLOG(ERROR) << "Can't change invertibility if transform is unchanged";

[ajuma, 2014/03/28 18:49:07]

How about a DCHECK instead of a DLOG?

[avallee, 2014/04/15 18:53:25]

Done.

+    }
+    return;
+  }
+  transform_ = transform;
+  transform_is_invertible_ = transform_is_invertible;
+  NoteLayerPropertyChangedForSubtree();
+}
+
 bool LayerImpl::TransformIsAnimating() const {
   return layer_animation_controller_->IsAnimatingProperty(Animation::Transform);
 }
 
 bool LayerImpl::TransformIsAnimatingOnImplOnly() const {
   Animation* transform_animation =
       layer_animation_controller_->GetAnimation(Animation::Transform);
   return transform_animation && transform_animation->is_impl_only();
 }
 
@@ skipping 479 matching lines @@
 scoped_ptr<base::Value> LayerImpl::AsValue() const {
   scoped_ptr<base::DictionaryValue> state(new base::DictionaryValue());
   AsValueInto(state.get());
   return state.PassAs<base::Value>();
 }
 
 void LayerImpl::RunMicroBenchmark(MicroBenchmarkImpl* benchmark) {
   benchmark->RunOnLayer(this);
 }
 }  // namespace cc