Save/restore PBO bindings in DrawingBuffer

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

 /*
  * 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 306 matching lines @@
         // owns the SharedBitmap.
         auto func = WTF::bind(&DrawingBuffer::softwareMailboxReleased,
             RefPtr<DrawingBuffer>(this),
             WTF::passed(std::move(bitmap)),
             m_size);
         *outReleaseCallback = cc::SingleReleaseCallback::Create(
             convertToBaseCallback(std::move(func)));
         return true;
     }
 
+    m_gl->BindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);

[Ken Russell (switch to Gerrit), 2016/09/09 20:10:33]

Here also, this needs to only be executed if the context is WebGL 2.0 / ES 3.0.

[Kai Ninomiya, 2016/09/09 20:30:44]

Done.

+
     // We must restore the texture binding since creating new textures,
     // consuming and producing mailboxes changes it.
     ScopedTextureUnit0BindingRestorer restorer(m_gl, m_activeTextureUnit, m_texture2DBinding);
 
     // First try to recycle an old buffer.
     RefPtr<MailboxInfo> mailboxInfo = takeRecycledMailbox();
 
     // No buffer available to recycle, create a new one.
     if (!mailboxInfo)
         mailboxInfo = createNewMailbox(createTextureAndAllocateMemory(m_size));
 
     if (m_preserveDrawingBuffer == Discard) {
         std::swap(mailboxInfo->textureInfo, m_colorBuffer);
         attachColorBufferToReadFramebuffer();
 
         if (m_discardFramebufferSupported) {
             // Explicitly discard framebuffer to save GPU memory bandwidth for tile-based GPU arch.
             const GLenum attachments[3] = { GL_COLOR_ATTACHMENT0, GL_DEPTH_ATTACHMENT, GL_STENCIL_ATTACHMENT };
             m_gl->BindFramebuffer(GL_FRAMEBUFFER, m_fbo);
             m_gl->DiscardFramebufferEXT(GL_FRAMEBUFFER, 3, attachments);
         }
     } else {
         m_gl->CopySubTextureCHROMIUM(m_colorBuffer.textureId, mailboxInfo->textureInfo.textureId,
             0, 0, 0, 0, m_size.width(), m_size.height(), GL_FALSE, GL_FALSE, GL_FALSE);
     }
 
     restoreFramebufferBindings();
+    restorePixelUnpackBufferBindings();
     m_contentsChanged = false;
 
     m_gl->ProduceTextureDirectCHROMIUM(mailboxInfo->textureInfo.textureId, mailboxInfo->textureInfo.parameters.target, mailboxInfo->mailbox.name);
     const GLuint64 fenceSync = m_gl->InsertFenceSyncCHROMIUM();
 #if OS(MACOSX)
     m_gl->DescheduleUntilFinishedCHROMIUM();
 #endif
     m_gl->Flush();
     gpu::SyncToken syncToken;
     m_gl->GenSyncTokenCHROMIUM(fenceSync, syncToken.GetData());
@@ skipping 583 matching lines @@
             m_gl->Enable(GL_SCISSOR_TEST);
     }
 
     m_gl->BindFramebuffer(GL_FRAMEBUFFER, m_fbo);
     if (m_antiAliasingMode == ScreenSpaceAntialiasing) {
         m_gl->ApplyScreenSpaceAntialiasingCHROMIUM();
     }
     m_contentsChangeCommitted = true;
 }
 
+void DrawingBuffer::restorePixelUnpackBufferBindings()
+{
+    m_gl->BindBuffer(GL_PIXEL_UNPACK_BUFFER, m_pixelUnpackBufferBinding);

[Ken Russell (switch to Gerrit), 2016/09/09 20:10:33]

This must only be done for WebGL 2.0 / ES 3.0 contexts.

+}
+
 void DrawingBuffer::restoreFramebufferBindings()
 {
     if (m_drawFramebufferBinding && m_readFramebufferBinding) {
         if (m_drawFramebufferBinding == m_readFramebufferBinding) {
             m_gl->BindFramebuffer(GL_FRAMEBUFFER, m_readFramebufferBinding);
         } else {
             m_gl->BindFramebuffer(GL_READ_FRAMEBUFFER, m_readFramebufferBinding);
             m_gl->BindFramebuffer(GL_DRAW_FRAMEBUFFER, m_drawFramebufferBinding);
         }
         return;
@@ skipping 261 matching lines @@
 
 void DrawingBuffer::restoreTextureBindings()
 {
     // This class potentially modifies the bindings for GL_TEXTURE_2D and
     // GL_TEXTURE_RECTANGLE. Only GL_TEXTURE_2D needs to be restored since
     // the public interface for WebGL does not support GL_TEXTURE_RECTANGLE.
     m_gl->BindTexture(GL_TEXTURE_2D, m_texture2DBinding);
 }
 
 } // namespace blink