Implement cc::FilterOperations::MapRect.

cc/output/filter_operations.cc

 // Copyright 2013 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/output/filter_operations.h"
 
 #include <stddef.h>
 
 #include <cmath>
+#include <numeric>
 
 #include "base/trace_event/trace_event_argument.h"
 #include "base/values.h"
 #include "cc/output/filter_operation.h"
+#include "ui/gfx/geometry/rect.h"
 
 namespace cc {
 
 FilterOperations::FilterOperations() {}
 
 FilterOperations::FilterOperations(const FilterOperations& other)
     : operations_(other.operations_) {}
 
 FilterOperations::~FilterOperations() {}
 
@@ skipping 25 matching lines @@
 }
 
 static int SpreadForStdDeviation(float std_deviation) {
   // https://dvcs.w3.org/hg/FXTF/raw-file/tip/filters/index.html#feGaussianBlurElement
   // provides this approximation for evaluating a gaussian blur by a triple box
   // filter.
   float d = floorf(std_deviation * 3.f * sqrt(8.f * atan(1.f)) / 4.f + 0.5f);
   return static_cast<int>(ceilf(d * 3.f / 2.f));
 }
 
+gfx::Rect FilterOperations::MapRect(const gfx::Rect& rect) const {
+  auto accumulate_rect = [](const gfx::Rect& rect, const FilterOperation& op) {
+    return op.MapRect(rect);
+  };
+  return std::accumulate(operations_.begin(), operations_.end(), rect,
+                         accumulate_rect);
+}
+
 void FilterOperations::GetOutsets(int* top,
                                   int* right,
                                   int* bottom,
                                   int* left) const {
   *top = *right = *bottom = *left = 0;
   for (size_t i = 0; i < operations_.size(); ++i) {
     const FilterOperation& op = operations_[i];
     // TODO(hendrikw): We should refactor some of this. See crbug.com/523534.
     if (op.type() == FilterOperation::REFERENCE) {
       if (!op.image_filter())
@@ skipping 143 matching lines @@
 void FilterOperations::AsValueInto(
     base::trace_event::TracedValue* value) const {
   for (size_t i = 0; i < operations_.size(); ++i) {
     value->BeginDictionary();
     operations_[i].AsValueInto(value);
     value->EndDictionary();
   }
 }
 
 }  // namespace cc