[PPAPI] Compositor API implementation

ppapi/examples/compositor/compositor.cc

 // Copyright 2014 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 <math.h>
+
+#include <vector>
+
 #include "ppapi/c/pp_errors.h"
-#include "ppapi/cpp/core.h"
+#include "ppapi/cpp/compositor.h"
+#include "ppapi/cpp/compositor_layer.h"
 #include "ppapi/cpp/graphics_3d.h"
 #include "ppapi/cpp/graphics_3d_client.h"
-#include "ppapi/cpp/input_event.h"
+#include "ppapi/cpp/image_data.h"
 #include "ppapi/cpp/instance.h"
 #include "ppapi/cpp/module.h"
 #include "ppapi/cpp/rect.h"
-#include "ppapi/examples/gles2_spinning_cube/spinning_cube.h"
+#include "ppapi/examples/compositor/spinning_cube.h"
 #include "ppapi/lib/gl/gles2/gl2ext_ppapi.h"
+#include "ppapi/lib/gl/include/GLES2/gl2.h"
+#include "ppapi/lib/gl/include/GLES2/gl2ext.h"
 #include "ppapi/utility/completion_callback_factory.h"
 
 // Use assert as a poor-man's CHECK, even in non-debug mode.
 // Since <assert.h> redefines assert on every inclusion (it doesn't use
 // include-guards), make sure this is the last file #include'd in this file.
 #undef NDEBUG
 #include <assert.h>
 
 namespace {
 
+const int32_t kTextureWidth = 800;
+const int32_t kTextureHeight = 800;
+const int32_t kImageWidth = 256;
+const int32_t kImageHeight = 256;
+
 class DemoInstance : public pp::Instance, public pp::Graphics3DClient {
  public:
   DemoInstance(PP_Instance instance);
   virtual ~DemoInstance();
 
   // pp::Instance implementation (see PPP_Instance).
   virtual bool Init(uint32_t argc, const char* argn[], const char* argv[]);
   virtual void DidChangeView(const pp::Rect& position,
                              const pp::Rect& clip);
-  virtual bool HandleInputEvent(const pp::InputEvent& event) {
-    // TODO(yzshen): Handle input events.
-    return true;
-  }
 
   // pp::Graphics3DClient implementation.
   virtual void Graphics3DContextLost();
 
  private:
   // GL-related functions.
   void InitGL(int32_t result);
-  void Paint(int32_t result);
+  GLuint PrepareFramebuffer();
+  pp::ImageData PrepareImage();
+  void Paint(int32_t result, int32_t frame);
+  void OnTextureReleased(int32_t result, GLuint texture);
+  void OnImageReleased(int32_t result, const pp::ImageData& image);
 
-  pp::Size plugin_size_;
   pp::CompletionCallbackFactory<DemoInstance> callback_factory_;
 
   // Owned data.
   pp::Graphics3D* context_;
 
-  SpinningCube cube_;
+  GLuint fbo_;
+  GLuint rbo_;
+
+  std::vector<GLuint> textures_;
+  std::vector<pp::ImageData> images_;
+
+  pp::Compositor compositor_;
+  pp::CompositorLayer color_layer_;
+  pp::CompositorLayer stable_texture_layer_;
+  pp::CompositorLayer texture_layer_;
+  pp::CompositorLayer image_layer_;
+
+  SpinningCube* cube_;
 };
 
 DemoInstance::DemoInstance(PP_Instance instance)
     : pp::Instance(instance),
       pp::Graphics3DClient(this),
       callback_factory_(this),
-      context_(NULL) {}
+      context_(NULL),
+      fbo_(0),
+      rbo_(0),
+      compositor_(this),
+      cube_(new SpinningCube()) {}
 
 DemoInstance::~DemoInstance() {
+  delete cube_;
   assert(glTerminatePPAPI());
   delete context_;
 }
 
 bool DemoInstance::Init(uint32_t /*argc*/,
                         const char* /*argn*/[],
                         const char* /*argv*/[]) {
-  RequestInputEvents(PP_INPUTEVENT_CLASS_MOUSE);
   return !!glInitializePPAPI(pp::Module::Get()->get_browser_interface());
 }
 
 void DemoInstance::DidChangeView(
     const pp::Rect& position, const pp::Rect& /*clip*/) {
   if (position.width() == 0 || position.height() == 0)
     return;
-  plugin_size_ = position.size();
-
   // Initialize graphics.
   InitGL(0);
 }
 
 void DemoInstance::Graphics3DContextLost() {
+  fbo_ = 0;
+  rbo_ = 0;
+  compositor_.ResetLayers();
+  color_layer_ = pp::CompositorLayer();
+  stable_texture_layer_ = pp::CompositorLayer();
+  texture_layer_ = pp::CompositorLayer();
+  image_layer_ = pp::CompositorLayer();
+  textures_.clear();
   delete context_;
   context_ = NULL;
+  cube_->OnGLContextLost();
   pp::CompletionCallback cb = callback_factory_.NewCallback(
       &DemoInstance::InitGL);
   pp::Module::Get()->core()->CallOnMainThread(0, cb, 0);
 }
 
 void DemoInstance::InitGL(int32_t /*result*/) {
-  assert(plugin_size_.width() && plugin_size_.height());
-
-  if (context_) {
-    context_->ResizeBuffers(plugin_size_.width(), plugin_size_.height());
+  if (context_)
     return;
-  }
   int32_t context_attributes[] = {
     PP_GRAPHICS3DATTRIB_ALPHA_SIZE, 8,
     PP_GRAPHICS3DATTRIB_BLUE_SIZE, 8,
     PP_GRAPHICS3DATTRIB_GREEN_SIZE, 8,
     PP_GRAPHICS3DATTRIB_RED_SIZE, 8,
     PP_GRAPHICS3DATTRIB_DEPTH_SIZE, 0,
     PP_GRAPHICS3DATTRIB_STENCIL_SIZE, 0,
     PP_GRAPHICS3DATTRIB_SAMPLES, 0,
     PP_GRAPHICS3DATTRIB_SAMPLE_BUFFERS, 0,
-    PP_GRAPHICS3DATTRIB_WIDTH, plugin_size_.width(),
-    PP_GRAPHICS3DATTRIB_HEIGHT, plugin_size_.height(),
+    PP_GRAPHICS3DATTRIB_WIDTH, 0,
+    PP_GRAPHICS3DATTRIB_HEIGHT, 0,
     PP_GRAPHICS3DATTRIB_NONE,
   };
   context_ = new pp::Graphics3D(this, context_attributes);
   assert(!context_->is_null());
-  assert(BindGraphics(*context_));
+  assert(BindGraphics(compositor_));
 
   glSetCurrentContextPPAPI(context_->pp_resource());
-  cube_.Init(plugin_size_.width(), plugin_size_.height());
-  Paint(PP_OK);
-}
-
-void DemoInstance::Paint(int32_t result) {
+
+  cube_->Init(kTextureWidth, kTextureHeight);
+
+  Paint(PP_OK, 0);
+}
+
+GLuint DemoInstance::PrepareFramebuffer() {
+  GLuint texture = 0;
+  if (textures_.empty()) {
+    // Create a texture object
+    glGenTextures(1, &texture);
+    glBindTexture(GL_TEXTURE_2D, texture);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, kTextureWidth, kTextureHeight, 0,
+                 GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+    // glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    // glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glBindTexture(GL_TEXTURE_2D, 0);
+  } else {
+    texture = textures_.back();
+    textures_.pop_back();
+  }
+
+  if (!rbo_) {
+    // create a renderbuffer object to store depth info
+    glGenRenderbuffers(1, &rbo_);
+    glBindRenderbuffer(GL_RENDERBUFFER, rbo_);
+    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT16,
+        kTextureWidth, kTextureHeight);
+    glBindRenderbuffer(GL_RENDERBUFFER, 0);
+  }
+
+  if (!fbo_) {
+    // create a framebuffer object
+    glGenFramebuffers(1, &fbo_);
+  }
+
+  glBindFramebuffer(GL_FRAMEBUFFER, fbo_);
+
+  // attach the texture to FBO color attachment point
+  glFramebufferTexture2D(GL_FRAMEBUFFER,
+                         GL_COLOR_ATTACHMENT0,
+                         GL_TEXTURE_2D,
+                         texture,
+                         0);
+
+  // attach the renderbuffer to depth attachment point
+  glFramebufferRenderbuffer(GL_FRAMEBUFFER,
+                            GL_DEPTH_ATTACHMENT,
+                            GL_RENDERBUFFER,
+                            rbo_);
+
+  // check FBO status
+  GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
+  assert(status == GL_FRAMEBUFFER_COMPLETE);
+
+  return texture;
+}
+
+pp::ImageData DemoInstance::PrepareImage() {
+  if (images_.empty()) {
+    return pp::ImageData(this,
+                         PP_IMAGEDATAFORMAT_RGBA_PREMUL,
+                         pp::Size(kImageWidth, kImageHeight),
+                         false);
+  }
+  pp::ImageData image = images_.back();
+  images_.pop_back();
+  return image;
+}
+
+void DemoInstance::Paint(int32_t result, int32_t frame) {
   if (result != PP_OK || !context_)
     return;
 
-  cube_.UpdateForTimeDelta(0.02f);
-  cube_.Draw();
-
-  context_->SwapBuffers(callback_factory_.NewCallback(&DemoInstance::Paint));
+  float factor_sin = sin(M_PI / 180 * frame);
+  float factor_cos = cos(M_PI / 180 * frame);
+  {
+    // Set the background color layer.
+    if (color_layer_.is_null()) {
+      color_layer_ = compositor_.AddLayer();
+      assert(!color_layer_.is_null());
+      static const float transform[16] = {
+        1.0f, 0.0f, 0.0f, 0.0f,
+        0.0f, 1.0f, 0.0f, 0.0f,
+        0.0f, 0.0f, 1.0f, 0.0f,
+        0.0f, 0.0f, 0.0f, 1.0f,
+      };
+      color_layer_.SetTransform(transform);
+    }
+    color_layer_.SetColor(fabs(factor_sin),
+                          fabs(factor_cos),
+                          fabs(factor_sin * factor_cos),
+                          1.0f,
+                          pp::Size(800, 600));
+  }
+
+  {
+    // Set the image layer
+    if (image_layer_.is_null()) {
+      image_layer_ = compositor_.AddLayer();
+      assert(!image_layer_.is_null());
+    }
+    float x = frame % 800;
+    float y = 200 - 200 * factor_sin;
+    const float transform[16] = {
+      fabs(factor_sin) + 0.2f, 0.0f, 0.0f, 0.0f,
+      0.0f, fabs(factor_sin) + 0.2f, 0.0f, 0.0f,
+      0.0f, 0.0f, 1.0f, 0.0f,
+         x,    y, 0.0f, 1.0f,
+    };
+    image_layer_.SetTransform(transform);
+    pp::ImageData image = PrepareImage();
+    uint8_t *p = static_cast<uint8_t*>(image.data());
+    for (int x = 0; x < kImageWidth; ++x) {
+      for (int y = 0; y < kImageHeight; ++y) {
+        *(p++) = frame;
+        *(p++) = frame * x;
+        *(p++) = frame * y;
+        *(p++) = 255;
+      }
+    }
+    image_layer_.SetImage(image, pp::Size(kImageWidth, kImageHeight),
+        callback_factory_.NewCallback(&DemoInstance::OnImageReleased, image));
+  }
+
+  {
+    // Set the stable texture layer
+    if (stable_texture_layer_.is_null()) {
+      stable_texture_layer_ = compositor_.AddLayer();
+      assert(!stable_texture_layer_.is_null());
+      stable_texture_layer_.SetPremultipliedAlpha(PP_FALSE);
+      // stable_texture_layer_.SetClipRect(pp::Rect(50, 50, 400, 400));
+      GLuint texture = PrepareFramebuffer();
+      cube_->UpdateForTimeDelta(0.02f);
+      cube_->Draw();
+      stable_texture_layer_.SetTexture(*context_, texture, pp::Size(600, 600),
+          callback_factory_.NewCallback(&DemoInstance::OnTextureReleased,
+                                        texture));
+    }
+    float x = 10 - 100 * factor_sin;
+    float y = 10 - 100 * factor_cos;
+    const float transform[16] = {
+      1.0f, 0.0f, 0.0f, 0.0f,
+      0.0f, 1.0f, 0.0f, 0.0f,
+      0.0f, 0.0f, 1.0f, 0.0f,
+         x,    y, 0.0f, 1.0f,
+    };
+    stable_texture_layer_.SetTransform(transform);
+  }
+
+  {
+    // Set the dynamic texture layer.
+    if (texture_layer_.is_null()) {
+      texture_layer_ = compositor_.AddLayer();
+      assert(!texture_layer_.is_null());
+      static const float transform[16] = {
+        1.0f, 0.0f, 0.0f, 0.0f,
+        0.0f, 1.0f, 0.0f, 0.0f,
+        0.0f, 0.0f, 1.0f, 0.0f,
+        200.0f, 0.0f, 0.0f, 1.0f,
+      };
+      texture_layer_.SetTransform(transform);
+      texture_layer_.SetPremultipliedAlpha(PP_FALSE);
+     }
+
+    GLuint texture = PrepareFramebuffer();
+    cube_->UpdateForTimeDelta(0.02f);
+    cube_->Draw();
+    texture_layer_.SetTexture(*context_, texture, pp::Size(400, 400),
+        callback_factory_.NewCallback(&DemoInstance::OnTextureReleased,
+                                      texture));
+  }
+
+  compositor_.CommitLayers(
+      callback_factory_.NewCallback(&DemoInstance::Paint, ++frame));
+}
+
+void DemoInstance::OnTextureReleased(int32_t result, GLuint texture) {
+  if (result == PP_OK)
+    textures_.push_back(texture);
+}
+
+void DemoInstance::OnImageReleased(int32_t result, const pp::ImageData& image) {
+  if (result == PP_OK);
+  images_.push_back(image);
 }
 
 // This object is the global object representing this plugin library as long
 // as it is loaded.
 class DemoModule : public pp::Module {
  public:
   DemoModule() : Module() {}
   virtual ~DemoModule() {}
 
   virtual pp::Instance* CreateInstance(PP_Instance instance) {
     return new DemoInstance(instance);
   }
 };
 
 }  // anonymous namespace
 
 namespace pp {
 // Factory function for your specialization of the Module object.
 Module* CreateModule() {
   return new DemoModule();
 }
 }  // namespace pp