Revert 168457 "WebGL: Transfer ownership of WebGraphicsContext3D..."

trunk/Source/platform/graphics/gpu/DrawingBuffer.cpp

Index: trunk/Source/platform/graphics/gpu/DrawingBuffer.cpp
===================================================================
--- trunk/Source/platform/graphics/gpu/DrawingBuffer.cpp	(revision 168480)
+++ trunk/Source/platform/graphics/gpu/DrawingBuffer.cpp	(working copy)
@@ -77,10 +77,9 @@
     Platform3DObject m_oldTextureUnitZeroId;
 };
 
-PassRefPtr<DrawingBuffer> DrawingBuffer::create(PassOwnPtr<blink::WebGraphicsContext3D> context, const IntSize& size, PreserveDrawingBuffer preserve, PassRefPtr<ContextEvictionManager> contextEvictionManager)
+PassRefPtr<DrawingBuffer> DrawingBuffer::create(blink::WebGraphicsContext3D* context, const IntSize& size, PreserveDrawingBuffer preserve, PassRefPtr<ContextEvictionManager> contextEvictionManager)
 {
-    ASSERT(context);
-    Extensions3DUtil extensionsUtil(context.get());
+    Extensions3DUtil extensionsUtil(context);
     bool multisampleSupported = extensionsUtil.supportsExtension("GL_CHROMIUM_framebuffer_multisample")
         && extensionsUtil.supportsExtension("GL_OES_rgb8_rgba8");
     if (multisampleSupported) {
@@ -91,13 +90,12 @@
     if (packedDepthStencilSupported)
         extensionsUtil.ensureExtensionEnabled("GL_OES_packed_depth_stencil");
 
-    RefPtr<DrawingBuffer> drawingBuffer = adoptRef(new DrawingBuffer(context, multisampleSupported, packedDepthStencilSupported, preserve, contextEvictionManager));
-    if (!drawingBuffer->initialize(size))
-        return PassRefPtr<DrawingBuffer>();
+    RefPtr<DrawingBuffer> drawingBuffer = adoptRef(new DrawingBuffer(context, size, multisampleSupported, packedDepthStencilSupported, preserve, contextEvictionManager));
     return drawingBuffer.release();
 }
 
-DrawingBuffer::DrawingBuffer(PassOwnPtr<blink::WebGraphicsContext3D> context,
+DrawingBuffer::DrawingBuffer(blink::WebGraphicsContext3D* context,
+    const IntSize& size,
     bool multisampleExtensionSupported,
     bool packedDepthStencilExtensionSupported,
     PreserveDrawingBuffer preserve,
@@ -126,12 +124,12 @@
     , m_colorFormat(0)
     , m_internalRenderbufferFormat(0)
     , m_maxTextureSize(0)
-    , m_sampleCount(0)
     , m_packAlignment(4)
     , m_contextEvictionManager(contextEvictionManager)
 {
     // Used by browser tests to detect the use of a DrawingBuffer.
     TRACE_EVENT_INSTANT0("test_gpu", "DrawingBufferCreation");
+    initialize(size);
 }
 
 DrawingBuffer::~DrawingBuffer()
@@ -158,12 +156,12 @@
 
 blink::WebGraphicsContext3D* DrawingBuffer::context()
 {
-    return m_context.get();
+    return m_context;
 }
 
 bool DrawingBuffer::prepareMailbox(blink::WebExternalTextureMailbox* outMailbox, blink::WebExternalBitmap* bitmap)
 {
-    if (!m_contentsChanged)
+    if (!m_context || !m_contentsChanged)
         return false;
 
     m_context->makeContextCurrent();
@@ -184,7 +182,7 @@
 
     // We must restore the texture binding since creating new textures,
     // consuming and producing mailboxes changes it.
-    ScopedTextureUnit0BindingRestorer restorer(m_context.get(), m_activeTextureUnit, m_texture2DBinding);
+    ScopedTextureUnit0BindingRestorer restorer(m_context, m_activeTextureUnit, m_texture2DBinding);
 
     // First try to recycle an old buffer.
     RefPtr<MailboxInfo> frontColorBufferMailbox = recycledMailbox();
@@ -247,7 +245,7 @@
 
 PassRefPtr<DrawingBuffer::MailboxInfo> DrawingBuffer::recycledMailbox()
 {
-    if (m_recycledMailboxes.isEmpty())
+    if (!m_context || m_recycledMailboxes.isEmpty())
         return PassRefPtr<MailboxInfo>();
 
     RefPtr<MailboxInfo> mailboxInfo = m_recycledMailboxes.last().release();
@@ -277,10 +275,11 @@
     return returnMailbox.release();
 }
 
-bool DrawingBuffer::initialize(const IntSize& size)
+void DrawingBuffer::initialize(const IntSize& size)
 {
+    ASSERT(m_context);
     m_attributes = m_context->getContextAttributes();
-    Extensions3DUtil extensionsUtil(m_context.get());
+    Extensions3DUtil extensionsUtil(m_context);
 
     if (m_attributes.alpha) {
         m_internalColorFormat = GL_RGBA;
@@ -313,12 +312,12 @@
     else
         m_context->framebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, m_colorBuffer, 0);
     createSecondaryBuffers();
-    return reset(size);
+    reset(size);
 }
 
 bool DrawingBuffer::copyToPlatformTexture(blink::WebGraphicsContext3D* context, Platform3DObject texture, GLenum internalFormat, GLenum destType, GLint level, bool premultiplyAlpha, bool flipY)
 {
-    if (!m_context->makeContextCurrent())
+    if (!m_context || !m_context->makeContextCurrent())
         return false;
     if (m_contentsChanged) {
         if (m_multisampleMode != None) {
@@ -364,6 +363,9 @@
 
 blink::WebLayer* DrawingBuffer::platformLayer()
 {
+    if (!m_context)
+        return 0;
+
     if (!m_layer) {
         m_layer = adoptPtr(blink::Platform::current()->compositorSupport()->createExternalTextureLayer(this));
 
@@ -378,7 +380,7 @@
 
 void DrawingBuffer::paintCompositedResultsToCanvas(ImageBuffer* imageBuffer)
 {
-    if (!m_context->makeContextCurrent() || m_context->getGraphicsResetStatusARB() != GL_NO_ERROR)
+    if (!m_context || !m_context->makeContextCurrent() || m_context->getGraphicsResetStatusARB() != GL_NO_ERROR)
         return;
 
     if (!imageBuffer)
@@ -419,37 +421,40 @@
     if (m_layer)
         m_layer->clearTexture();
 
-    m_context->flush();
+    if (m_context)
+        m_context->flush();
 }
 
 void DrawingBuffer::releaseResources()
 {
-    m_context->makeContextCurrent();
+    if (m_context) {
+        m_context->makeContextCurrent();
 
-    clearPlatformLayer();
+        clearPlatformLayer();
 
-    for (size_t i = 0; i < m_textureMailboxes.size(); i++)
-        m_context->deleteTexture(m_textureMailboxes[i]->textureId);
+        for (size_t i = 0; i < m_textureMailboxes.size(); i++)
+            m_context->deleteTexture(m_textureMailboxes[i]->textureId);
 
-    if (m_multisampleColorBuffer)
-        m_context->deleteRenderbuffer(m_multisampleColorBuffer);
+        if (m_multisampleColorBuffer)
+            m_context->deleteRenderbuffer(m_multisampleColorBuffer);
 
-    if (m_depthStencilBuffer)
-        m_context->deleteRenderbuffer(m_depthStencilBuffer);
+        if (m_depthStencilBuffer)
+            m_context->deleteRenderbuffer(m_depthStencilBuffer);
 
-    if (m_depthBuffer)
-        m_context->deleteRenderbuffer(m_depthBuffer);
+        if (m_depthBuffer)
+            m_context->deleteRenderbuffer(m_depthBuffer);
 
-    if (m_stencilBuffer)
-        m_context->deleteRenderbuffer(m_stencilBuffer);
+        if (m_stencilBuffer)
+            m_context->deleteRenderbuffer(m_stencilBuffer);
 
-    if (m_multisampleFBO)
-        m_context->deleteFramebuffer(m_multisampleFBO);
+        if (m_multisampleFBO)
+            m_context->deleteFramebuffer(m_multisampleFBO);
 
-    if (m_fbo)
-        m_context->deleteFramebuffer(m_fbo);
+        if (m_fbo)
+            m_context->deleteFramebuffer(m_fbo);
 
-    m_context.clear();
+        m_context = 0;
+    }
 
     setSize(IntSize());
 
@@ -474,6 +479,9 @@
 
 unsigned DrawingBuffer::createColorTexture(const IntSize& size)
 {
+    if (!m_context)
+        return 0;
+
     unsigned offscreenColorTexture = m_context->createTexture();
     if (!offscreenColorTexture)
         return 0;
@@ -590,6 +598,9 @@
 
 void DrawingBuffer::clearFramebuffers(GLbitfield clearMask)
 {
+    if (!m_context)
+        return;
+
     // We will clear the multisample FBO, but we also need to clear the non-multisampled buffer.
     if (m_multisampleFBO) {
         m_context->bindFramebuffer(GL_FRAMEBUFFER, m_fbo);
@@ -657,9 +668,11 @@
     return adjustedSize;
 }
 
-bool DrawingBuffer::reset(const IntSize& newSize)
+void DrawingBuffer::reset(const IntSize& newSize)
 {
-    ASSERT(!newSize.isEmpty());
+    if (!m_context)
+        return;
+
     IntSize adjustedSize;
     bool evictContext = false;
     bool isNewContext = m_size.isEmpty();
@@ -669,7 +682,7 @@
         adjustedSize = adjustSize(newSize);
 
     if (adjustedSize.isEmpty())
-        return false;
+        return;
 
     if (evictContext)
         m_contextEvictionManager->forciblyLoseOldestContext("WARNING: WebGL contexts have exceeded the maximum allowed backbuffer area. Oldest context will be lost.");
@@ -687,7 +700,7 @@
         setSize(adjustedSize);
 
         if (adjustedSize.isEmpty())
-            return false;
+            return;
     }
 
     m_context->disable(GL_SCISSOR_TEST);
@@ -707,11 +720,13 @@
     }
 
     clearFramebuffers(clearMask);
-    return true;
 }
 
 void DrawingBuffer::commit(long x, long y, long width, long height)
 {
+    if (!m_context)
+        return;
+
     if (width < 0)
         width = m_size.width();
     if (height < 0)
@@ -739,7 +754,7 @@
 
 void DrawingBuffer::restoreFramebufferBinding()
 {
-    if (!m_framebufferBinding)
+    if (!m_context || !m_framebufferBinding)
         return;
 
     m_context->bindFramebuffer(GL_FRAMEBUFFER, m_framebufferBinding);
@@ -752,6 +767,9 @@
 
 void DrawingBuffer::bind()
 {
+    if (!m_context)
+        return;
+
     m_context->bindFramebuffer(GL_FRAMEBUFFER, m_multisampleFBO ? m_multisampleFBO : m_fbo);
 }