Fixed regression in WEBGL_draw_buffers support

third_party/WebKit/Source/modules/webgl/WebGLDrawBuffers.cpp

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 #include "modules/webgl/WebGLDrawBuffers.h"
 
 #include "gpu/command_buffer/client/gles2_interface.h"
 #include "modules/webgl/WebGLFramebuffer.h"
+#include "wtf/Assertions.h"

[Zhenyao Mo, 2016/04/14 20:15:15]

why do you need this?

 
 namespace blink {
 
 WebGLDrawBuffers::WebGLDrawBuffers(WebGLRenderingContextBase* context)
     : WebGLExtension(context)
 {
     context->extensionsUtil()->ensureExtensionEnabled("GL_EXT_draw_buffers");
 }
 
 WebGLDrawBuffers::~WebGLDrawBuffers()
@@ skipping 93 matching lines @@
         gl->GenTextures(1, &depth);
         gl->BindTexture(GL_TEXTURE_2D, depth);
         gl->TexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, 1, 1, 0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, buffer);
     }
 
     Vector<Platform3DObject> colors;
     bool ok = true;
     GLint maxAllowedBuffers = std::min(maxDrawBuffers, maxColorAttachments);
     for (GLint i = 0; i < maxAllowedBuffers; ++i) {
         GLuint color;
+

[Ken Russell (switch to Gerrit), 2016/04/14 20:33:08]

If you can undo this whitespace change and the one below it might make it easier
to merge this back to earlier releases.

         gl->GenTextures(1, &color);
         colors.append(color);
         gl->BindTexture(GL_TEXTURE_2D, color);
         gl->TexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 1, 1, 0, GL_RGBA, GL_UNSIGNED_BYTE, buffer);
         gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0 + i, GL_TEXTURE_2D, color, 0);
         if (gl->CheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
             ok = false;
             break;
         }
         if (supportsDepth) {
             gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depth, 0);
             if (gl->CheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
                 ok = false;
                 break;
             }
             gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, 0, 0);
         }
         if (supportsDepthStencil) {
-            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthStencil, 0);
-            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_TEXTURE_2D, depthStencil, 0);
+            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_TEXTURE_2D, depthStencil, 0);

[Ken Russell (switch to Gerrit), 2016/04/14 20:33:08]

Could you please add a comment that the DEPTH_STENCIL synthetic attachment (it's
synthetic for ES 2.0, anyway) is being emulated for WebGL contexts at the
command buffer level?

A similar comment would be appropriate in DrawingBuffer::resizeDepthStencil,
Source/platform/graphics/gpu/DrawingBuffer.cpp.

Thanks.

             if (gl->CheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
                 ok = false;
                 break;
             }
-            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, 0, 0);
-            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_STENCIL_ATTACHMENT, GL_TEXTURE_2D, 0, 0);
+            gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_TEXTURE_2D, 0, 0);
         }
     }
 
     webglContext->restoreCurrentFramebuffer();
     gl->DeleteFramebuffers(1, &fbo);
     webglContext->restoreCurrentTexture2D();
     if (supportsDepth)
         gl->DeleteTextures(1, &depth);
     if (supportsDepthStencil)
         gl->DeleteTextures(1, &depthStencil);
     gl->DeleteTextures(colors.size(), colors.data());
+
     return ok;
 }
 
 } // namespace blink