Make the Pepper proxy support in-process font rendering.

ppapi/shared_impl/webkit_forwarding.h

+// Copyright (c) 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.
+
+#ifndef PPAPI_SHARED_IMPL_WEBKIT_FORWARDING_H_
+#define PPAPI_SHARED_IMPL_WEBKIT_FORWARDING_H_
+
+#include <string>
+
+#include "ppapi/c/pp_bool.h"
+#include "ppapi/c/pp_stdint.h"
+
+struct PP_FontDescription_Dev;
+struct PP_FontMetrics_Dev;
+struct PP_Point;
+struct PP_Rect;
+
+namespace base {
+class WaitableEvent;
+}
+
+namespace skia {
+class PlatformCanvas;
+}
+
+namespace pp {
+namespace shared_impl {
+
+class WebKitForwarding {
+ public:
+  class Font {
+   public:
+    // C++ version of PP_TextRun_Dev. Since the functions below will be called
+    // on an alternate thread in the proxy, and since there are different
+    // methods of converting PP_Var -> strings in the plugin and the proxy, we
+    // can't use PP_Vars in the Do* functions below.
+    struct TextRun {
+      std::string text;
+      bool rtl;
+      bool override_direction;
+    };
+
+    // DoDrawText takes too many arguments to be used with base::Bind, so we
+    // use this struct to hold them.
+    struct DrawTextParams {
+      DrawTextParams(skia::PlatformCanvas* destination_arg,
+                     const TextRun& text_arg,
+                     const PP_Point* position_arg,
+                     uint32_t color_arg,
+                     const PP_Rect* clip_arg,
+                     PP_Bool image_data_is_opaque_arg);
+      ~DrawTextParams();
+
+      skia::PlatformCanvas* destination;
+      const TextRun& text;
+      const PP_Point* position;
+      uint32_t color;
+      const PP_Rect* clip;
+      PP_Bool image_data_is_opaque;
+    };
+
+    virtual ~Font();
+
+    // The face name in the description is not filled in to avoid a dependency
+    // on creating vars. Instead, the face name is placed into the given
+    // string. See class description for waitable_event documentation. If
+    // non-null, the given event will be set on completion.
+    virtual void Describe(base::WaitableEvent* event,
+                          PP_FontDescription_Dev* description,
+                          std::string* face,
+                          PP_FontMetrics_Dev* metrics,
+                          PP_Bool* result) = 0;
+    virtual void DrawTextAt(base::WaitableEvent* event,
+                            const DrawTextParams& params) = 0;
+    virtual void MeasureText(base::WaitableEvent* event,
+                             const TextRun& text,
+                             int32_t* result) = 0;
+    virtual void CharacterOffsetForPixel(base::WaitableEvent* event,
+                                         const TextRun& text,
+                                         int32_t pixel_position,
+                                         uint32_t* result) = 0;
+    virtual void PixelOffsetForCharacter(base::WaitableEvent* event,
+                                         const TextRun& text,
+                                         uint32_t char_offset,
+                                         int32_t* result) = 0;
+  };
+
+  virtual ~WebKitForwarding();
+
+  // Creates a new font with the given description. The desc_face is the face
+  // name already extracted from the description. The caller owns the result
+  // pointer, which will never be NULL. If non-null, the given event will be
+  // set on completion.
+  virtual void CreateFontForwarding(base::WaitableEvent* event,
+                                    const PP_FontDescription_Dev& desc,
+                                    const std::string& desc_face,
+                                    Font** result) = 0;
+
+};
+
+}  // namespace shared_impl
+}  // namespace pp
+
+#endif  // PPAPI_SHARED_IMPL_WEBKIT_FORWARDING_H_