DrawingBuffer cleanup: Merge structures

third_party/WebKit/Source/platform/graphics/gpu/DrawingBuffer.h

 /*
  * Copyright (c) 2010, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 299 matching lines @@
     GLenum target = 0;
     GLenum internalColorFormat = 0;
 
     // The internal color format used when allocating storage for the
     // texture. This may be different from internalColorFormat if RGB
     // emulation is required.
     GLenum creationInternalColorFormat = 0;
     GLenum colorFormat = 0;
   };
 
-  // If we used CHROMIUM_image as the backing storage for our buffers,
-  // we need to know the mapping from texture id to image.
-  struct TextureInfo {
-    DISALLOW_NEW();
+  struct ColorBuffer : public RefCounted<ColorBuffer> {
+    ColorBuffer(DrawingBuffer*, const TextureParameters&, const IntSize&);
+    ~ColorBuffer();

[ccameron, 2016/10/06 09:24:53]

This destructor now deletes the GL resources.

+
+    // The owning DrawingBuffer. Note that DrawingBuffer is explicitly destroyed
+    // by the beginDestruction method, which will eventually drain all of its
+    // ColorBuffers.
+    RefPtr<DrawingBuffer> drawingBuffer;
+
+    const TextureParameters parameters;
+    const IntSize size;
+
     GLuint textureId = 0;
     GLuint imageId = 0;
-    TextureParameters parameters;
-  };
 
-  struct MailboxInfo : public RefCounted<MailboxInfo> {
-    MailboxInfo() = default;
+    // The mailbox used to send this buffer to the compositor.
     gpu::Mailbox mailbox;

[ccameron, 2016/10/06 09:24:53]

This was previously MailboxInfo::mailbox, FrontBufferInfo::mailbox, and
RecycledMailbox::mailbox, and used as a key to map between them.

-    TextureInfo textureInfo;
-    IntSize size;
+
+    // The sync token for when this buffer was sent to the compositor.
+    gpu::SyncToken produceSyncToken;

[ccameron, 2016/10/06 09:24:53]

This was previously FrontBufferInfo::produceSyncToken.

+
+    // The sync token for when this buffer was received back from the
+    // compositor.
+    gpu::SyncToken receiveSyncToken;

[ccameron, 2016/10/06 09:24:53]

This was previously RecycledMailbox::syncToken.

 
    private:
-    WTF_MAKE_NONCOPYABLE(MailboxInfo);
+    WTF_MAKE_NONCOPYABLE(ColorBuffer);
   };
 
   bool prepareTextureMailboxInternal(
       cc::TextureMailbox* outMailbox,
       std::unique_ptr<cc::SingleReleaseCallback>* outReleaseCallback,
       bool forceGpuResult);
 
   // Callbacks for mailboxes given to the compositor from PrepareTextureMailbox.
-  void gpuMailboxReleased(const gpu::Mailbox&,
+  void gpuMailboxReleased(RefPtr<ColorBuffer>,
                           const gpu::SyncToken&,
                           bool lostResource);
   void softwareMailboxReleased(std::unique_ptr<cc::SharedBitmap>,
                                const IntSize&,
                                const gpu::SyncToken&,
                                bool lostResource);
 
   // The texture parameters to use for a texture that will be backed by a
   // CHROMIUM_image.
   TextureParameters chromiumImageTextureParameters();
 
   // The texture parameters to use for a default texture.
   TextureParameters defaultTextureParameters();
 
   // Creates and binds a texture with the given parameters. Returns 0 on
   // failure, or the newly created texture id on success. The caller takes
   // ownership of the newly created texture.
   GLuint createColorTexture(const TextureParameters&);
 
   // Attempts to allocator storage for, or resize all buffers. Returns whether
   // the operation was successful.
   bool resizeDefaultFramebuffer(const IntSize&);
 
   void clearPlatformLayer();
 
-  PassRefPtr<MailboxInfo> takeRecycledMailbox();
-  PassRefPtr<MailboxInfo> createNewMailbox(const TextureInfo&);
-  void deleteMailbox(const gpu::Mailbox&, const gpu::SyncToken&);
-  void freeRecycledMailboxes();
+  PassRefPtr<ColorBuffer> takeRecycledMailbox();
 
   std::unique_ptr<cc::SharedBitmap> createOrRecycleBitmap();
 
   // Updates the current size of the buffer, ensuring that
   // s_currentResourceUsePixels is updated.
   void setSize(const IntSize& size);
 
   // This is the order of bytes to use when doing a readback.
   enum ReadbackOrder { ReadbackRGBA, ReadbackSkia };
 
@@ skipping 10 matching lines @@
 
   // Allocate a storage texture if possible. Otherwise, allocate a regular
   // texture.
   void allocateConditionallyImmutableTexture(GLenum target,
                                              GLenum internalformat,
                                              GLsizei width,
                                              GLsizei height,
                                              GLint border,
                                              GLenum format,
                                              GLenum type);
-  // Allocate buffer storage to be sent to compositor using either texImage2D or
-  // CHROMIUM_image based on available support.
-  void deleteChromiumImageForTexture(TextureInfo*);
 
   // If RGB emulation is required, then the CHROMIUM image's alpha channel
   // must be immediately cleared after it is bound to a texture. Nothing
   // should be allowed to change the alpha channel after this.
-  void clearChromiumImageAlpha(const TextureInfo&);
+  void clearChromiumImageAlpha(const ColorBuffer&);
 
   // Tries to create a CHROMIUM_image backed texture if
   // RuntimeEnabledFeatures::webGLImageChromiumEnabled() is true. On failure,
   // or if the flag is false, creates a default texture.
-  TextureInfo createTextureAndAllocateMemory(const IntSize&);
+  RefPtr<ColorBuffer> createTextureAndAllocateMemory(const IntSize&);
 
   // Creates and allocates space for a default texture.
-  TextureInfo createDefaultTextureAndAllocateMemory(const IntSize&);
+  RefPtr<ColorBuffer> createDefaultTextureAndAllocateMemory(const IntSize&);
 
-  // Attaches |m_colorBuffer| to |m_fbo|, which is always the source for read
-  // operations.
+  // Attaches |m_backColorBuffer| to |m_fbo|, which is always the source for
+  // read operations.
   void attachColorBufferToReadFramebuffer();
 
   // Whether the WebGL client desires an explicit resolve. This is
   // implemented by forwarding all draw operations to a multisample
   // renderbuffer, which is resolved before any read operations or swaps.
   bool wantExplicitResolve();
 
   // Whether the WebGL client wants a depth or stencil buffer.
   bool wantDepthOrStencil();
 
@@ skipping 16 matching lines @@
   // Lifetime is tied to the m_contextProvider.
   gpu::gles2::GLES2Interface* m_gl;
   std::unique_ptr<Extensions3DUtil> m_extensionsUtil;
   IntSize m_size = {-1, -1};
   const bool m_discardFramebufferSupported;
   const bool m_wantAlphaChannel;
   const bool m_premultipliedAlpha;
   const bool m_softwareRendering;
   bool m_hasImplicitStencilBuffer = false;
   bool m_storageTextureSupported = false;
-  struct FrontBufferInfo {
-    gpu::Mailbox mailbox;
-    gpu::SyncToken produceSyncToken;
-    TextureInfo texInfo;
-  };
-  FrontBufferInfo m_frontColorBuffer;
+
+  // This is the ColorBuffer that was most recently presented to the compositor
+  // by prepareTextureMailboxInternal.
+  RefPtr<ColorBuffer> m_frontColorBuffer;
 
   std::unique_ptr<WTF::Closure> m_newMailboxCallback;
 
   // This is used when the user requests either a depth or stencil buffer.
   GLuint m_depthStencilBuffer = 0;
 
   // When wantExplicitResolve() returns true, the target of all draw
   // operations.
   GLuint m_multisampleFBO = 0;
 
   // The id of the renderbuffer storage for |m_multisampleFBO|.
   GLuint m_multisampleRenderbuffer = 0;
 
   // When wantExplicitResolve() returns false, the target of all draw and
   // read operations. When wantExplicitResolve() returns true, the target of
-  // all read operations. A swap is performed by exchanging |m_colorBuffer|
+  // all read operations. A swap is performed by exchanging |m_backColorBuffer|
   // with |m_frontColorBuffer|.
   GLuint m_fbo = 0;
 
   // All information about the texture storage for |m_fbo|.
-  TextureInfo m_colorBuffer;
+  RefPtr<ColorBuffer> m_backColorBuffer;
 
   // True if our contents have been modified since the last presentation of this
   // buffer.
   bool m_contentsChanged = true;
 
   // True if commit() has been called since the last time markContentsChanged()
   // had been called.
   bool m_contentsChangeCommitted = false;
   bool m_bufferClearNeeded = false;
 
@@ skipping 12 matching lines @@
 
   int m_maxTextureSize = 0;
   int m_sampleCount = 0;
   int m_packAlignment = 4;
   bool m_destructionInProgress = false;
   bool m_isHidden = false;
   SkFilterQuality m_filterQuality = kLow_SkFilterQuality;
 
   std::unique_ptr<WebExternalTextureLayer> m_layer;
 
-  // All of the mailboxes that this DrawingBuffer has ever created.
-  Vector<RefPtr<MailboxInfo>> m_textureMailboxes;

[ccameron, 2016/10/06 09:24:53]

m_textureMailboxes was serving as a O(n) lookup of some texture information from
mailbox. We now just point to the structures directly.

-  struct RecycledMailbox : RefCounted<RecycledMailbox> {
-    RecycledMailbox(const gpu::Mailbox& mailbox,
-                    const gpu::SyncToken& syncToken)
-        : mailbox(mailbox), syncToken(syncToken) {}
-
-    gpu::Mailbox mailbox;
-    gpu::SyncToken syncToken;
-
-   private:
-    WTF_MAKE_NONCOPYABLE(RecycledMailbox);
-  };
   // Mailboxes that were released by the compositor can be used again by this
   // DrawingBuffer.
-  Deque<RefPtr<RecycledMailbox>> m_recycledMailboxQueue;
+  Deque<RefPtr<ColorBuffer>> m_recycledMailboxQueue;
 
   // If the width and height of the Canvas's backing store don't
   // match those that we were given in the most recent call to
   // reshape(), then we need an intermediate bitmap to read back the
   // frame buffer into. This seems to happen when CSS styles are
   // used to resize the Canvas.
   SkBitmap m_resizingBitmap;
 
   // Used to flip a bitmap vertically.
   Vector<uint8_t> m_scanline;
 
   // In the case of OffscreenCanvas, we do not want to enable the
   // WebGLImageChromium flag, so we replace all the
   // RuntimeEnabledFeatures::webGLImageChromiumEnabled() call with
   // shouldUseChromiumImage() calls, and set m_chromiumImageUsage to
   // DisallowChromiumImage in the case of OffscreenCanvas.
   ChromiumImageUsage m_chromiumImageUsage;
   bool shouldUseChromiumImage();
 };
 
 }  // namespace blink
 
 #endif  // DrawingBuffer_h