gpu: Remove WebGraphicsContext3D::makeContextCurrent() in Blink

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 205 matching lines @@
 
     if (m_destructionInProgress) {
         // It can be hit in the following sequence.
         // 1. WebGL draws something.
         // 2. The compositor begins the frame.
         // 3. Javascript makes a context lost using WEBGL_lose_context extension.
         // 4. Here.
         return false;
     }
 
-    m_context->makeContextCurrent();
-
     // Resolve the multisampled buffer into m_colorBuffer texture.
     if (m_multisampleMode != None)
         commit();
 
     if (bitmap) {
         bitmap->setSize(size());
 
         unsigned char* pixels = bitmap->pixels();
         bool needPremultiply = m_actualAttributes.alpha && !m_actualAttributes.premultipliedAlpha;
         WebGLImageConversion::AlphaOp op = needPremultiply ? WebGLImageConversion::AlphaDoPremultiply : WebGLImageConversion::AlphaDoNothing;
@@ skipping 72 matching lines @@
             m_recycledMailboxQueue.prepend(mailboxInfo->mailbox);
             return;
         }
     }
     ASSERT_NOT_REACHED();
 }
 
 void DrawingBuffer::mailboxReleasedWithoutRecycling(const WebExternalTextureMailbox& mailbox)
 {
     ASSERT(m_textureMailboxes.size());
-    m_context->makeContextCurrent();
     // Ensure not to call the destructor until deleteMailbox() is completed.
     RefPtr<DrawingBuffer> self = this;
     deleteMailbox(mailbox);
 }
 
 PassRefPtr<DrawingBuffer::MailboxInfo> DrawingBuffer::recycledMailbox()
 {
     if (m_recycledMailboxQueue.isEmpty())
         return PassRefPtr<MailboxInfo>();
 
@@ skipping 50 matching lines @@
             m_context->deleteTexture(m_textureMailboxes[i]->textureInfo.textureId);
             m_textureMailboxes.remove(i);
             return;
         }
     }
     ASSERT_NOT_REACHED();
 }
 
 bool DrawingBuffer::initialize(const IntSize& size)
 {
-    if (!m_context->makeContextCurrent()) {
-        // Most likely the GPU process exited and the attempt to reconnect to it failed.
-        // Need to try to restore the context again later.
-        return false;
-    }
-
     if (m_context->isContextLost()) {
         // Need to try to restore the context again later.
         return false;
     }
 
     if (m_requestedAttributes.alpha) {
         m_internalColorFormat = GL_RGBA;
         m_colorFormat = GL_RGBA;
         m_internalRenderbufferFormat = GL_RGBA8_OES;
     } else {
@@ skipping 42 matching lines @@
         WGC3Dint stencilBits = 0;
         m_context->getIntegerv(GL_STENCIL_BITS, &stencilBits);
         m_actualAttributes.stencil = stencilBits > 0;
     }
     m_actualAttributes.antialias = multisample();
     return true;
 }
 
 bool DrawingBuffer::copyToPlatformTexture(WebGraphicsContext3D* context, Platform3DObject texture, GLenum internalFormat, GLenum destType, GLint level, bool premultiplyAlpha, bool flipY, bool fromFrontBuffer)
 {
-    if (!m_context->makeContextCurrent())
-        return false;
-
     GLint textureId = m_colorBuffer.textureId;
     if (fromFrontBuffer && m_frontColorBuffer.textureId)
         textureId = m_frontColorBuffer.textureId;
 
     if (m_contentsChanged) {
         if (m_multisampleMode != None) {
             commit();
             if (!m_framebufferBinding)
                 bind();
             else
                 restoreFramebufferBinding();
         }
         m_context->flush();
     }
 
     if (!Extensions3DUtil::canUseCopyTextureCHROMIUM(internalFormat, destType, level))
         return false;
 
     // Contexts may be in a different share group. We must transfer the texture through a mailbox first
     RefPtr<MailboxInfo> bufferMailbox = adoptRef(new MailboxInfo());
     m_context->genMailboxCHROMIUM(bufferMailbox->mailbox.name);
     m_context->produceTextureDirectCHROMIUM(textureId, GL_TEXTURE_2D, bufferMailbox->mailbox.name);
     m_context->flush();
 
     bufferMailbox->mailbox.syncPoint = m_context->insertSyncPoint();
 
-    if (!context->makeContextCurrent())
-        return false;
-
     context->waitSyncPoint(bufferMailbox->mailbox.syncPoint);
     Platform3DObject sourceTexture = context->createAndConsumeTextureCHROMIUM(GL_TEXTURE_2D, bufferMailbox->mailbox.name);
 
     bool unpackPremultiplyAlphaNeeded = false;
     bool unpackUnpremultiplyAlphaNeeded = false;
     if (m_actualAttributes.alpha && m_actualAttributes.premultipliedAlpha && !premultiplyAlpha)
         unpackUnpremultiplyAlphaNeeded = true;
     else if (m_actualAttributes.alpha && !m_actualAttributes.premultipliedAlpha && premultiplyAlpha)
         unpackPremultiplyAlphaNeeded = true;
 
@@ skipping 27 matching lines @@
         m_layer->setBlendBackgroundColor(m_actualAttributes.alpha);
         m_layer->setPremultipliedAlpha(m_actualAttributes.premultipliedAlpha);
         GraphicsLayer::registerContentsLayer(m_layer->layer());
     }
 
     return m_layer->layer();
 }
 
 void DrawingBuffer::paintCompositedResultsToCanvas(ImageBuffer* imageBuffer)
 {
-    if (!m_context->makeContextCurrent() || m_context->getGraphicsResetStatusARB() != GL_NO_ERROR)
+    if (m_context->getGraphicsResetStatusARB() != GL_NO_ERROR)
         return;
 
     if (!imageBuffer)
         return;
     Platform3DObject tex = imageBuffer->getBackingTexture();
     if (tex) {
         RefPtr<MailboxInfo> bufferMailbox = adoptRef(new MailboxInfo());
         m_context->genMailboxCHROMIUM(bufferMailbox->mailbox.name);
         m_context->produceTextureDirectCHROMIUM(m_frontColorBuffer.textureId, GL_TEXTURE_2D, bufferMailbox->mailbox.name);
         m_context->flush();
 
         bufferMailbox->mailbox.syncPoint = m_context->insertSyncPoint();
         OwnPtr<WebGraphicsContext3DProvider> provider =
             adoptPtr(Platform::current()->createSharedOffscreenGraphicsContext3DProvider());
         if (!provider)
             return;
         WebGraphicsContext3D* context = provider->context3d();
-        if (!context || !context->makeContextCurrent())
+        if (!context)
             return;
 
         context->waitSyncPoint(bufferMailbox->mailbox.syncPoint);
         Platform3DObject sourceTexture = context->createAndConsumeTextureCHROMIUM(GL_TEXTURE_2D, bufferMailbox->mailbox.name);
         context->copyTextureCHROMIUM(GL_TEXTURE_2D, sourceTexture,
             tex, 0, GL_RGBA, GL_UNSIGNED_BYTE);
         context->deleteTexture(sourceTexture);
         context->flush();
         m_context->waitSyncPoint(context->insertSyncPoint());
         return;
@@ skipping 16 matching lines @@
         m_layer->clearTexture();
 
     m_context->flush();
 }
 
 void DrawingBuffer::beginDestruction()
 {
     ASSERT(!m_destructionInProgress);
     m_destructionInProgress = true;
 
-    m_context->makeContextCurrent();
-
     clearPlatformLayer();
 
     while (!m_recycledMailboxQueue.isEmpty())
         deleteMailbox(m_recycledMailboxQueue.takeLast());
 
     if (m_multisampleFBO)
         m_context->deleteFramebuffer(m_multisampleFBO);
 
     if (m_fbo)
         m_context->deleteFramebuffer(m_fbo);
@@ skipping 274 matching lines @@
     return true;
 }
 
 void DrawingBuffer::commit(long x, long y, long width, long height)
 {
     if (width < 0)
         width = m_size.width();
     if (height < 0)
         height = m_size.height();
 
-    m_context->makeContextCurrent();
-
     if (m_multisampleFBO && !m_contentsChangeCommitted) {
         m_context->bindFramebuffer(GL_READ_FRAMEBUFFER_ANGLE, m_multisampleFBO);
         m_context->bindFramebuffer(GL_DRAW_FRAMEBUFFER_ANGLE, m_fbo);
 
         if (m_scissorEnabled)
             m_context->disable(GL_SCISSOR_TEST);
 
         // Use NEAREST, because there is no scale performed during the blit.
         m_context->blitFramebufferCHROMIUM(x, y, width, height, x, y, width, height, GL_COLOR_BUFFER_BIT, GL_NEAREST);
 
@@ skipping 167 matching lines @@
 void DrawingBuffer::deleteChromiumImageForTexture(TextureInfo* info)
 {
     if (info->imageId) {
         m_context->releaseTexImage2DCHROMIUM(GL_TEXTURE_2D, info->imageId);
         m_context->destroyImageCHROMIUM(info->imageId);
         info->imageId = 0;
     }
 }
 
 } // namespace blink