// Copyright (c) 2010 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 WEBKIT_GLUE_PLUGINS_MAC_GPU_PLUGIN_CONTAINER_H_
#define WEBKIT_GLUE_PLUGINS_MAC_GPU_PLUGIN_CONTAINER_H_

// The "GPU plugin" is currently implemented as a special kind of
// NPAPI plugin to provide high-performance on-screen 3D rendering for
// Pepper 3D.
//
// On Windows and X11 platforms the GPU plugin relies on cross-process
// parenting of windows, which is not supported via any public APIs in
// the Mac OS X window system.
//
// To achieve full hardware acceleration we use the new IOSurface APIs
// introduced in Mac OS X 10.6. The GPU plugin's process produces an
// IOSurface and renders into it using OpenGL. It uses the
// IOSurfaceGetID and IOSurfaceLookup APIs to pass a reference to this
// surface to the browser process for on-screen rendering. The GPU
// plugin essentially looks like a windowless plugin; the browser
// process gets all of the mouse events, because the plugin process
// does not have an on-screen window.
//
// This class encapsulates some of the management of these data
// structures, in conjunction with the MacGPUPluginContainerManager.

#include <CoreFoundation/CoreFoundation.h>
#include <OpenGL/OpenGL.h>

#include "app/gfx/native_widget_types.h"
#include "base/basictypes.h"

namespace webkit_glue {
struct WebPluginGeometry;
}

class MacGPUPluginContainerManager;

class MacGPUPluginContainer {
 public:
  MacGPUPluginContainer();
  virtual ~MacGPUPluginContainer();

  // Sets the backing store and size of this plugin container.
  void SetSizeAndBackingStore(int32 width,
                              int32 height,
                              uint64 io_surface_identifier,
                              MacGPUPluginContainerManager* manager);

  // Tells the plugin container that it has moved relative to the
  // origin of the window, for example because of a scroll event.
  void MoveTo(const webkit_glue::WebPluginGeometry& geom);

  // Draws this plugin's contents, texture mapped onto a quad in the
  // given OpenGL context. TODO(kbr): figure out and define exactly
  // how the coordinate system will work out.
  void Draw(CGLContextObj context);

  // Enqueue our texture for later deletion. Call this before deleting
  // this object.
  void EnqueueTextureForDeletion(MacGPUPluginContainerManager* manager);

 private:
  // We currently only have a viable implementation of this class on
  // Snow Leopard. We need to think about fallback strategies that
  // will work on Leopard.

  // The x and y coordinates of the plugin window on the web page.
  // TODO(kbr): see whether additional clipping information is
  // necessary.
  int x_;
  int y_;

  void ReleaseIOSurface();

  // The IOSurfaceRef, if any, that has been handed from the GPU
  // plugin process back to the browser process for drawing.
  // This is held as a CFTypeRef because we can't refer to the
  // IOSurfaceRef type when building on 10.5.
  CFTypeRef surface_;

  // The width and height of the surface.
  int32 width_;
  int32 height_;

  // The "live" OpenGL texture referring to this IOSurfaceRef. Note
  // that per the CGLTexImageIOSurface2D API we do not need to
  // explicitly update this texture's contents once created. All we
  // need to do is ensure it is re-bound before attempting to draw
  // with it.
  GLuint texture_;

  DISALLOW_COPY_AND_ASSIGN(MacGPUPluginContainer);
};

#endif  // WEBKIT_GLUE_PLUGINS_MAC_GPU_PLUGIN_CONTAINER_H_