Revert "Delete CC."

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 <cmath>
+
+#include "base/trace_event/trace_event_argument.h"
+#include "base/values.h"
+#include "cc/output/filter_operation.h"
+
+namespace cc {
+
+FilterOperations::FilterOperations() {}
+
+FilterOperations::FilterOperations(const FilterOperations& other)
+    : operations_(other.operations_) {}
+
+FilterOperations::~FilterOperations() {}
+
+FilterOperations& FilterOperations::operator=(const FilterOperations& other) {
+  operations_ = other.operations_;
+  return *this;
+}
+
+bool FilterOperations::operator==(const FilterOperations& other) const {
+  if (other.size() != size())
+    return false;
+  for (size_t i = 0; i < size(); ++i) {
+    if (other.at(i) != at(i))
+      return false;
+  }
+  return true;
+}
+
+void FilterOperations::Append(const FilterOperation& filter) {
+  operations_.push_back(filter);
+}
+
+void FilterOperations::Clear() {
+  operations_.clear();
+}
+
+bool FilterOperations::IsEmpty() const {
+  return operations_.empty();
+}
+
+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));
+}
+
+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(ajuma): Add support for reference filters once SkImageFilter
+    // reports its outsets.
+    DCHECK(op.type() != FilterOperation::REFERENCE);
+    if (op.type() == FilterOperation::BLUR ||
+        op.type() == FilterOperation::DROP_SHADOW) {
+      int spread = SpreadForStdDeviation(op.amount());
+      if (op.type() == FilterOperation::BLUR) {
+        *top += spread;
+        *right += spread;
+        *bottom += spread;
+        *left += spread;
+      } else {
+        *top += spread - op.drop_shadow_offset().y();
+        *right += spread + op.drop_shadow_offset().x();
+        *bottom += spread + op.drop_shadow_offset().y();
+        *left += spread - op.drop_shadow_offset().x();
+      }
+    }
+  }
+}
+
+bool FilterOperations::HasFilterThatMovesPixels() const {
+  for (size_t i = 0; i < operations_.size(); ++i) {
+    const FilterOperation& op = operations_[i];
+    // TODO(ajuma): Once SkImageFilter reports its outsets, use those here to
+    // determine whether a reference filter really moves pixels.
+    switch (op.type()) {
+      case FilterOperation::BLUR:
+      case FilterOperation::DROP_SHADOW:
+      case FilterOperation::ZOOM:
+      case FilterOperation::REFERENCE:
+        return true;
+      case FilterOperation::OPACITY:
+      case FilterOperation::COLOR_MATRIX:
+      case FilterOperation::GRAYSCALE:
+      case FilterOperation::SEPIA:
+      case FilterOperation::SATURATE:
+      case FilterOperation::HUE_ROTATE:
+      case FilterOperation::INVERT:
+      case FilterOperation::BRIGHTNESS:
+      case FilterOperation::CONTRAST:
+      case FilterOperation::SATURATING_BRIGHTNESS:
+      case FilterOperation::ALPHA_THRESHOLD:
+        break;
+    }
+  }
+  return false;
+}
+
+bool FilterOperations::HasFilterThatAffectsOpacity() const {
+  for (size_t i = 0; i < operations_.size(); ++i) {
+    const FilterOperation& op = operations_[i];
+    // TODO(ajuma): Make this smarter for reference filters. Once SkImageFilter
+    // can report affectsOpacity(), call that.
+    switch (op.type()) {
+      case FilterOperation::OPACITY:
+      case FilterOperation::BLUR:
+      case FilterOperation::DROP_SHADOW:
+      case FilterOperation::ZOOM:
+      case FilterOperation::REFERENCE:
+      case FilterOperation::ALPHA_THRESHOLD:
+        return true;
+      case FilterOperation::COLOR_MATRIX: {
+        const SkScalar* matrix = op.matrix();
+        if (matrix[15] ||
+            matrix[16] ||
+            matrix[17] ||
+            matrix[18] != 1 ||
+            matrix[19])
+          return true;
+        break;
+      }
+      case FilterOperation::GRAYSCALE:
+      case FilterOperation::SEPIA:
+      case FilterOperation::SATURATE:
+      case FilterOperation::HUE_ROTATE:
+      case FilterOperation::INVERT:
+      case FilterOperation::BRIGHTNESS:
+      case FilterOperation::CONTRAST:
+      case FilterOperation::SATURATING_BRIGHTNESS:
+        break;
+    }
+  }
+  return false;
+}
+
+bool FilterOperations::HasReferenceFilter() const {
+  for (size_t i = 0; i < operations_.size(); ++i) {
+    if (operations_[i].type() == FilterOperation::REFERENCE)
+      return true;
+  }
+  return false;
+}
+
+FilterOperations FilterOperations::Blend(const FilterOperations& from,
+                                         double progress) const {
+  if (HasReferenceFilter() || from.HasReferenceFilter())
+    return *this;
+
+  bool from_is_longer = from.size() > size();
+
+  size_t shorter_size, longer_size;
+  if (size() == from.size()) {
+    shorter_size = longer_size = size();
+  } else if  (from_is_longer) {
+    longer_size = from.size();
+    shorter_size = size();
+  } else {
+    longer_size = size();
+    shorter_size = from.size();
+  }
+
+  for (size_t i = 0; i < shorter_size; i++) {
+    if (from.at(i).type() != at(i).type())
+      return *this;
+  }
+
+  FilterOperations blended_filters;
+  for (size_t i = 0; i < shorter_size; i++) {
+    blended_filters.Append(
+        FilterOperation::Blend(&from.at(i), &at(i), progress));
+  }
+
+  if (from_is_longer) {
+    for (size_t i = shorter_size; i < longer_size; i++) {
+      blended_filters.Append(
+          FilterOperation::Blend(&from.at(i), NULL, progress));
+    }
+  } else {
+    for (size_t i = shorter_size; i < longer_size; i++)
+      blended_filters.Append(FilterOperation::Blend(NULL, &at(i), progress));
+  }
+
+  return blended_filters;
+}
+
+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