[PPAPI] Compositor API implementation

content/renderer/pepper/pepper_compositor_host.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 "content/renderer/pepper/pepper_compositor_host.h"
+
+#include "base/logging.h"
+#include "base/memory/shared_memory.h"
+#include "cc/layers/layer.h"
+#include "cc/layers/solid_color_layer.h"
+#include "cc/layers/texture_layer.h"
+#include "cc/resources/texture_mailbox.h"
+#include "content/public/renderer/renderer_ppapi_host.h"
+#include "content/renderer/pepper/gfx_conversion.h"
+#include "content/renderer/pepper/host_globals.h"
+#include "content/renderer/pepper/pepper_plugin_instance_impl.h"
+#include "content/renderer/pepper/ppb_image_data_impl.h"
+#include "ppapi/c/pp_errors.h"
+#include "ppapi/host/dispatch_host_message.h"
+#include "ppapi/host/ppapi_host.h"
+#include "ppapi/proxy/ppapi_messages.h"
+#include "ppapi/thunk/enter.h"
+#include "ppapi/thunk/ppb_image_data_api.h"
+#include "third_party/khronos/GLES2/gl2.h"
+#include "ui/gfx/transform.h"
+
+using ppapi::host::HostMessageContext;
+using ppapi::thunk::EnterResourceNoLock;
+using ppapi::thunk::PPB_ImageData_API;
+
+namespace content {
+
+PepperCompositorHost::PepperCompositorHost(
+    RendererPpapiHost* host,
+    PP_Instance instance,
+    PP_Resource resource)
+    : ResourceHost(host->GetPpapiHost(), instance, resource),
+      bound_instance_(NULL),
+      weak_factory_(this) {
+  layer_ = cc::Layer::Create();
+  // TODO(penghuang): SetMasksToBounds() can be expensive if the layer is
+  // transformed. Possibly better could be to explicitly clip the child layers
+  // (by modifying their bounds).
+  layer_->SetMasksToBounds(true);
+  layer_->SetIsDrawable(true);
+}
+
+PepperCompositorHost::~PepperCompositorHost() {
+  // Unbind from the instance when destroyed if we're still bound.
+  if (bound_instance_)
+    bound_instance_->BindGraphics(bound_instance_->pp_instance(), 0);
+}
+
+bool PepperCompositorHost::BindToInstance(
+    PepperPluginInstanceImpl* new_instance) {
+  if (new_instance && new_instance->pp_instance() != pp_instance())
+    return false;  // Can't bind other instance's contexts.
+  if (bound_instance_ == new_instance)
+    return true;  // Rebinding the same device, nothing to do.
+  if (bound_instance_ && new_instance) {
+    NOTREACHED();
+    return false;  // Can't change a bound device.
+  }
+  bound_instance_ = new_instance;
+  return true;
+}
+
+void PepperCompositorHost::ViewInitiatedPaint() {
+  if (!commit_layers_reply_context_.is_valid())
+    return;
+  host()->SendReply(commit_layers_reply_context_,
+                    PpapiPluginMsg_Compositor_CommitLayersReply());
+  commit_layers_reply_context_ = ppapi::host::ReplyMessageContext();
+}
+
+void PepperCompositorHost::ViewFlushedPaint() {}
+
+void PepperCompositorHost::ResourceReleased(int32_t id,
+                                            uint32_t sync_point,
+                                            bool is_lost) {
+  host()->SendUnsolicitedReply(
+      pp_resource(),
+      PpapiPluginMsg_Compositor_ReleaseResource(id, sync_point, is_lost));
+}
+
+void PepperCompositorHost::ImageReleased(
+    int32_t id,
+    const scoped_ptr<base::SharedMemory>& shared_memory,
+    uint32_t sync_point,
+    bool is_lost) {
+  ResourceReleased(id, sync_point, is_lost);
+}
+
+int32_t PepperCompositorHost::OnResourceMessageReceived(
+    const IPC::Message& msg,
+    HostMessageContext* context) {
+  PPAPI_BEGIN_MESSAGE_MAP(PepperCompositorHost, msg)
+  PPAPI_DISPATCH_HOST_RESOURCE_CALL(
+      PpapiHostMsg_Compositor_CommitLayers, OnHostMsgCommitLayers)
+  PPAPI_END_MESSAGE_MAP()
+  return ppapi::host::ResourceHost::OnResourceMessageReceived(msg, context);
+}
+
+bool PepperCompositorHost::IsCompositorHost() {
+  return true;
+}
+
+int32_t PepperCompositorHost::VerifyCommittedLayers(
+    const std::vector<ppapi::CompositorLayerData>& layers,
+    bool reset) {
+  for (size_t i = 0; i < layers.size(); ++i) {
+    const LayerData* data = NULL;
+    const ppapi::CompositorLayerData* old_layer = NULL;
+    const ppapi::CompositorLayerData* new_layer = &layers[i];
+    // Make sure the layer type is not changed.
+    if (!reset) {
+      data = i >= layers_.size() ? NULL : &layers_[i];
+      DCHECK(!data || data->cc_layer);
+      old_layer = data ? &data->pp_layer : NULL;
+      if (old_layer && old_layer->type != new_layer->type) {
+        NOTREACHED();
+        return PP_ERROR_BADARGUMENT;
+      }
+    }
+
+    if (new_layer->type == ppapi::CompositorLayerData::TYPE_COLOR)
+      continue;
+
+    // Check texture layer.
+    if (new_layer->type == ppapi::CompositorLayerData::TYPE_TEXTURE) {
+      if (old_layer && new_layer->resource_id == old_layer->resource_id) {
+        if (memcmp(new_layer->texture.mailbox,
+                   old_layer->texture.mailbox,
+                   sizeof(ppapi::CompositorLayerData::Mailbox)) != 0) {
+          NOTREACHED();
+          return PP_ERROR_BADARGUMENT;
+        }
+      } else {
+        gpu::Mailbox gpu_mailbox;
+        gpu_mailbox.SetName(new_layer->texture.mailbox);
+        if (!gpu_mailbox.Verify()) {
+          NOTREACHED();
+          return PP_ERROR_BADARGUMENT;
+        }
+      }
+      continue;
+    }
+
+    // Check image layer.
+    if (new_layer->type == ppapi::CompositorLayerData::TYPE_IMAGE) {
+      if (old_layer && new_layer->resource_id == old_layer->resource_id) {
+        if (new_layer->image.host_resource != old_layer->image.host_resource) {
+          return PP_ERROR_BADARGUMENT;
+        }
+      } else {
+        EnterResourceNoLock<PPB_ImageData_API> enter(
+            new_layer->image.host_resource, true);
+        if (enter.failed()) {
+          NOTREACHED();
+          return PP_ERROR_BADRESOURCE;
+        }
+
+        // TODO(penghuang): support all kinds of image.
+        PP_ImageDataDesc desc;
+        if (enter.object()->Describe(&desc) != PP_TRUE ||
+            desc.stride != desc.size.width * 4 ||
+            desc.format != PP_IMAGEDATAFORMAT_RGBA_PREMUL) {
+          NOTREACHED();
+          return PP_ERROR_BADARGUMENT;
+        }
+
+        int handle;
+        uint32_t byte_count;
+        if (enter.object()->GetSharedMemory(&handle, &byte_count) != PP_OK)
+          return PP_ERROR_FAILED;
+      }
+      continue;
+    }
+    return PP_ERROR_BADARGUMENT;
+  }
+  return PP_OK;
+}

[raymes, 2014/06/06 00:47:00]

What I meant was to pull out just the body of the loop into the function. So you
would have 
for (size_t i = 0; i < layers.size(); ++i) {
 if (VerifyCommittedLayers(layers[i]) != PP_OK)
   return ...

I think this will make it much easier to read than at present where there are a
bunch of continues and so on.

[Peng, 2014/06/06 19:29:43]

Done.

+
+void PepperCompositorHost::UpdateLayer(
+    const scoped_refptr<cc::Layer>& layer,
+    const ppapi::CompositorLayerData* old_layer,
+    const ppapi::CompositorLayerData* new_layer) {
+  DCHECK(!old_layer || new_layer->type == old_layer->type);
+
+  // Always update properties on cc::Layer, because cc::Layer
+  // will ignore any setting with unchanged value.
+  layer->SetIsDrawable(true);
+  layer->SetBlendMode(SkXfermode::kSrcOver_Mode);
+  layer->SetOpacity(new_layer->opacity);
+  layer->SetBounds(PP_ToGfxSize(new_layer->size));
+
+  gfx::Transform transform(gfx::Transform::kSkipInitialization);
+  transform.matrix().setColMajorf(new_layer->transform);
+  layer->SetTransform(transform);
+
+  // Consider a (0,0,0,0) rect as no clip rect.
+  if (new_layer->clip_rect.point.x != 0 ||
+      new_layer->clip_rect.point.y != 0 ||
+      new_layer->clip_rect.size.width != 0 ||
+      new_layer->clip_rect.size.height != 0) {
+    scoped_refptr<cc::Layer> clip_parent = layer->parent();
+    if (clip_parent == layer_) {
+      // Create a clip parent layer, if it does not exist.
+      clip_parent = cc::Layer::Create();
+      clip_parent->SetMasksToBounds(true);
+      clip_parent->SetIsDrawable(true);
+      layer_->ReplaceChild(layer, clip_parent);
+      clip_parent->AddChild(layer);
+    }
+    gfx::Point position = PP_ToGfxPoint(new_layer->clip_rect.point);
+    clip_parent->SetPosition(position);
+    clip_parent->SetBounds(PP_ToGfxSize(new_layer->clip_rect.size));
+    layer->SetPosition(gfx::Point(-position.x(), -position.y()));
+  } else if (layer->parent() != layer_) {
+    // Remove the clip parent layer.
+    layer_->ReplaceChild(layer->parent(), layer);
+    layer->SetPosition(gfx::Point());
+  }
+
+  if (new_layer->type == ppapi::CompositorLayerData::TYPE_COLOR) {
+    layer->SetBackgroundColor(SkColorSetARGBMacro(new_layer->color.alpha * 255,
+                                                  new_layer->color.red * 255,
+                                                  new_layer->color.green * 255,
+                                                  new_layer->color.blue * 255));
+  } else if (new_layer->type == ppapi::CompositorLayerData::TYPE_TEXTURE) {
+    scoped_refptr<cc::TextureLayer> texture_layer(
+        static_cast<cc::TextureLayer*>(layer.get()));
+    if (!old_layer || new_layer->resource_id != old_layer->resource_id) {
+      gpu::Mailbox gpu_mailbox;
+      gpu_mailbox.SetName(new_layer->texture.mailbox);
+      DCHECK(gpu_mailbox.Verify());
+      cc::TextureMailbox mailbox(gpu_mailbox,
+                                 GL_TEXTURE_2D,
+                                 new_layer->texture.sync_point);
+      texture_layer->SetTextureMailbox(mailbox,
+          cc::SingleReleaseCallback::Create(
+              base::Bind(&PepperCompositorHost::ResourceReleased,
+                         weak_factory_.GetWeakPtr(),
+                         new_layer->resource_id)));;
+    }
+    texture_layer->SetPremultipliedAlpha(new_layer->texture.premult_alpha);
+    gfx::RectF rect = PP_ToGfxRectF(new_layer->texture.source_rect);
+    texture_layer->SetUV(rect.origin(), rect.bottom_right());
+  } else if (new_layer->type == ppapi::CompositorLayerData::TYPE_IMAGE) {
+    if (!old_layer || new_layer->resource_id != old_layer->resource_id) {
+      scoped_refptr<cc::TextureLayer> image_layer(
+          static_cast<cc::TextureLayer*>(layer.get()));
+      EnterResourceNoLock<PPB_ImageData_API> enter(
+          new_layer->image.host_resource, true);
+      DCHECK(enter.succeeded());
+      PP_ImageDataDesc desc;
+      {
+        PP_Bool rv = enter.object()->Describe(&desc);
+        DCHECK_EQ(rv, PP_TRUE);
+      }
+      int handle;
+      uint32_t byte_count;
+      {
+        int32_t rv = enter.object()->GetSharedMemory(&handle, &byte_count);
+        DCHECK_EQ(rv, PP_OK);
+      }
+#if defined(OS_WIN)
+      base::SharedMemoryHandle shm_handle =
+          static_cast<base::SharedMemoryHandle>(_dup(handle));
+#else
+      base::SharedMemoryHandle shm_handle(dup(handle), false);
+#endif
+      // Use a scoped_ptr to keep shared_memory alive until
+      // PepperCompositorHost::ImageReleased is called.
+      scoped_ptr<base::SharedMemory> shared_memory(
+          new base::SharedMemory(shm_handle, true));
+      CHECK(shared_memory->Map(desc.stride * desc.size.height));
+      cc::TextureMailbox mailbox(shared_memory.get(),
+                                 PP_ToGfxSize(desc.size));
+      image_layer->SetTextureMailbox(mailbox,
+          cc::SingleReleaseCallback::Create(
+              base::Bind(&PepperCompositorHost::ImageReleased,
+                         weak_factory_.GetWeakPtr(),
+                         new_layer->resource_id,
+                         base::Passed(&shared_memory))));
+
+      // ImageData is always premultiplied alpha.
+      image_layer->SetPremultipliedAlpha(true);
+    }
+  }
+}
+
+int32_t PepperCompositorHost::OnHostMsgCommitLayers(
+    HostMessageContext* context,
+    const std::vector<ppapi::CompositorLayerData>& layers,
+    bool reset) {
+  // Do not support CommitLayers() on an unbounded compositor.
+  if (!bound_instance_)
+    return PP_ERROR_FAILED;
+
+  if (commit_layers_reply_context_.is_valid()) {
+    NOTREACHED();
+    return PP_ERROR_INPROGRESS;
+  }
+
+  commit_layers_reply_context_ = context->MakeReplyMessageContext();
+
+  // Verfiy the layers first, if an error happens, we will return the error to
+  // plugin and keep current layers set by the previous CommitLayers()
+  // unchanged.
+  int32_t rv = VerifyCommittedLayers(layers, reset);
+  if (rv != PP_OK)
+    return rv;
+
+  // ResetLayers() has been called, we need rebuild layer stack.
+  if (reset) {
+    layer_->RemoveAllChildren();
+    layers_.clear();
+  }
+
+  for (size_t i = 0; i < layers.size(); ++i) {
+    const ppapi::CompositorLayerData& pp_layer = layers[i];
+    LayerData* data = i >= layers_.size() ? NULL : &layers_[i];
+    DCHECK(!data || data->cc_layer);
+    scoped_refptr<cc::Layer> cc_layer = data ? data->cc_layer : NULL;
+    ppapi::CompositorLayerData* old_layer = data ? &data->pp_layer : NULL;
+
+    if (!cc_layer) {
+      if (pp_layer.type == ppapi::CompositorLayerData::TYPE_COLOR) {
+        cc_layer = cc::SolidColorLayer::Create();
+      } else if (pp_layer.type == ppapi::CompositorLayerData::TYPE_TEXTURE ||
+               pp_layer.type == ppapi::CompositorLayerData::TYPE_IMAGE) {
+        cc_layer = cc::TextureLayer::CreateForMailbox(NULL);
+      }
+      layer_->AddChild(cc_layer);
+    }
+
+    UpdateLayer(cc_layer, old_layer, &pp_layer);
+
+    if (old_layer) {
+      *old_layer = pp_layer;
+    } else {
+      layers_.push_back(LayerData(cc_layer, pp_layer));
+    }
+  }
+
+  return PP_OK_COMPLETIONPENDING;
+}
+
+}  // namespace content