gpu: Mailbox emulation with EGLImage

gpu/command_buffer/service/mailbox_synchronizer.cc

+// Copyright (c) 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 "gpu/command_buffer/service/mailbox_synchronizer.h"
+
+#include "base/bind.h"
+#include "gpu/command_buffer/service/mailbox_manager.h"
+#include "gpu/command_buffer/service/texture_manager.h"
+
+namespace gpu {
+namespace gles2 {
+
+namespace {
+
+MailboxSynchronizer* g_instance = NULL;
+
+}  // anonymous namespace
+
+// static
+bool MailboxSynchronizer::Initialize() {
+  DCHECK(!g_instance);
+  g_instance = new MailboxSynchronizer;
+  return true;
+}
+
+// static
+void MailboxSynchronizer::Terminate() {
+  DCHECK(g_instance);
+  delete g_instance;
+  g_instance = NULL;
+}
+
+// static
+MailboxSynchronizer* MailboxSynchronizer::GetInstance() {
+  return g_instance;
+}
+
+MailboxSynchronizer::TargetName::TargetName(unsigned target,
+                                            const Mailbox& mailbox)
+    : target(target), mailbox(mailbox) {}
+
+MailboxSynchronizer::MailboxSynchronizer() {}
+
+MailboxSynchronizer::~MailboxSynchronizer() {
+}
+
+Texture* MailboxSynchronizer::CreateTextureFromMailbox(MailboxManager* manager,
+                                                       unsigned target,
+                                                       const Mailbox& mailbox) {
+  base::AutoLock lock(lock_);
+  TargetName target_name(target, mailbox);
+  MailboxMap::const_iterator it = mailboxes_.find(target_name);
+  if (it != mailboxes_.end()) {
+    linked_ptr<GlobalMailbox> info = it->second;
+    DCHECK(find(info->refs.begin(), info->refs.end(), manager) ==
+           info->refs.end());
+    Texture* texture = info->definition.CreateTexture();
+    if (texture)
+      it->second->refs.insert(manager);
+    return texture;
+  }
+
+  return NULL;
+}
+
+void MailboxSynchronizer::TextureDeleted(MailboxManager* manager,
+                                         unsigned target,
+                                         const Mailbox& mailbox) {
+  base::AutoLock lock(lock_);
+  TargetName target_name(target, mailbox);
+  MailboxMap::iterator it = mailboxes_.find(target_name);
+  if (it != mailboxes_.end()) {
+    size_t count = it->second->refs.erase(manager);
+    DCHECK_EQ(count, 1U);
+    if (it->second->refs.empty())
+      mailboxes_.erase(it);
+  }
+}
+
+void MailboxSynchronizer::PushTextureUpdates(MailboxManager* manager) {
+  base::AutoLock lock(lock_);
+  scoped_refptr<SharedGLFence> fence(new SharedGLFence);
+  for (MailboxManager::MailboxToTextureMap::const_iterator texture_it =
+           manager->mailbox_to_textures_.begin();
+       texture_it != manager->mailbox_to_textures_.end();
+       texture_it++) {
+    TargetName target_name(texture_it->first.target, texture_it->first.mailbox);
+    Texture* texture = texture_it->second->first;
+    // TODO(sievers)
+    bool needs_mips = texture->min_filter() != GL_NEAREST &&
+                      texture->min_filter() != GL_LINEAR;
+    if (target_name.target != GL_TEXTURE_2D || needs_mips)
+      continue;
+
+    MailboxMap::iterator it = mailboxes_.find(target_name);
+    if (it != mailboxes_.end()) {
+      // TODO: Different texture produced into an existing mailbox needs to
+      // decouple it from updates to previously shared textures in other
+      // contexts.
+      bool texture_has_image =
+          texture->GetLevelImage(texture->target(), 0) != NULL;
+      it->second->definition = TextureDefinition(
+          target_name.target,
+          texture,
+          texture_has_image ? it->second->definition.image() : NULL,
+          fence);
+      it->second->refs.insert(manager);
+    } else {
+      // TODO: If the texture is associated with another mailbox though,
+      // we need to reuse the same EGLImage.
+      mailboxes_[target_name] = make_linked_ptr(new GlobalMailbox(
+          TextureDefinition(target_name.target, texture, NULL, fence)));
+      mailboxes_[target_name]->refs.insert(manager);
+    }
+  }
+}
+
+void MailboxSynchronizer::PullTextureUpdates(MailboxManager* manager) {
+  base::AutoLock lock(lock_);
+  for (MailboxManager::MailboxToTextureMap::const_iterator texture_it =
+           manager->mailbox_to_textures_.begin();
+       texture_it != manager->mailbox_to_textures_.end();
+       texture_it++) {
+    TargetName target_name(texture_it->first.target, texture_it->first.mailbox);
+    MailboxMap::iterator it = mailboxes_.find(target_name);
+    if (it != mailboxes_.end()) {
+      it->second->definition.UpdateTexture(texture_it->second->first);
+    }
+  }
+}
+
+}  // namespace gles2
+}  // namespace gpu