Add a Paint::toString() method to describe our Paint objects.

sky/engine/core/painting/Paint.cpp

 // Copyright 2015 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 "sky/engine/config.h"
 #include "sky/engine/core/painting/Paint.h"
 
 #include "sky/engine/core/painting/ColorFilter.h"
 #include "sky/engine/core/painting/DrawLooper.h"
 #include "sky/engine/core/painting/MaskFilter.h"
 #include "sky/engine/core/painting/Shader.h"
+#include "sky/engine/wtf/text/StringBuilder.h"
+#include "third_party/skia/include/core/SkColorFilter.h"
+#include "third_party/skia/include/core/SkMaskFilter.h"
+#include "third_party/skia/include/core/SkShader.h"
+#include "third_party/skia/include/core/SkString.h"
 
 namespace blink {
 
-Paint::Paint()
-{
-    setIsAntiAlias(true);
+namespace {
+
+template <typename T>
+void SkToString(const char* title, const T* sk_object, StringBuilder* result) {
+  if (!sk_object)
+    return;
+  SkString string;
+  sk_object->toString(&string);
+  result->append(String::format(", %s: %s", title, string.c_str()));
 }
 
-Paint::~Paint()
-{
 }
 
-void Paint::setDrawLooper(DrawLooper* looper)
-{
-    ASSERT(looper);
-    m_paint.setLooper(looper->looper());
+Paint::Paint() {
+  setIsAntiAlias(true);
 }
 
-void Paint::setColorFilter(ColorFilter* filter)
-{
-    ASSERT(filter);
-    m_paint.setColorFilter(filter->filter());
+Paint::~Paint() {
 }
 
-void Paint::setMaskFilter(MaskFilter* filter)
-{
-    ASSERT(filter);
-    m_paint.setMaskFilter(filter->filter());
+void Paint::setDrawLooper(DrawLooper* looper) {
+  ASSERT(looper);
+  paint_.setLooper(looper->looper());
 }
 
-void Paint::setShader(Shader* shader)
-{
-    ASSERT(shader);
-    m_paint.setShader(shader->shader());
+void Paint::setColorFilter(ColorFilter* filter) {
+  ASSERT(filter);
+  paint_.setColorFilter(filter->filter());
 }
 
-void Paint::setStyle(SkPaint::Style style)
-{
-    m_paint.setStyle(style);
+void Paint::setMaskFilter(MaskFilter* filter) {
+  ASSERT(filter);
+  paint_.setMaskFilter(filter->filter());
 }
 
-void Paint::setTransferMode(SkXfermode::Mode transfer_mode)
-{
-    m_paint.setXfermodeMode(transfer_mode);
+void Paint::setShader(Shader* shader) {
+  ASSERT(shader);
+  paint_.setShader(shader->shader());
 }
 
-} // namespace blink
+void Paint::setStyle(SkPaint::Style style) {
+  paint_.setStyle(style);
+}
+
+void Paint::setTransferMode(SkXfermode::Mode transfer_mode) {
+  paint_.setXfermodeMode(transfer_mode);
+}
+
+String Paint::toString() const {
+  StringBuilder result;
+
+  result.append("Paint(");
+
+  result.append(String::format("color:Color(0x%.8x)", paint_.getColor()));
+
+  SkToString("shader", paint_.getShader(), &result);
+  SkToString("colorFilter", paint_.getColorFilter(), &result);
+  SkToString("maskFilter", paint_.getMaskFilter(), &result);
+
+  if (paint_.getLooper()) {
+    // TODO(mpcomplete): Figure out how to show a drawLooper.
+    result.append(", drawLooper:true");
+  }
+  result.append(")");
+
+  return result.toString();
+}
+
+}  // namespace blink