Move the WebGL DrawBuffers support check to the command buffer service.

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

 /*
  * Copyright (C) 2013 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 27 matching lines @@
 WebGLExtensionName WebGLDrawBuffers::name() const {
   return WebGLDrawBuffersName;
 }
 
 WebGLDrawBuffers* WebGLDrawBuffers::create(WebGLRenderingContextBase* context) {
   return new WebGLDrawBuffers(context);
 }
 
 // static
 bool WebGLDrawBuffers::supported(WebGLRenderingContextBase* context) {
-  return (context->extensionsUtil()->supportsExtension("GL_EXT_draw_buffers") &&
-          satisfiesWebGLRequirements(context));
+  return context->extensionsUtil()->supportsExtension("GL_EXT_draw_buffers");
 }
 
 // static
 const char* WebGLDrawBuffers::extensionName() {
   return "WEBGL_draw_buffers";
 }
 
 void WebGLDrawBuffers::drawBuffersWEBGL(const Vector<GLenum>& buffers) {
   WebGLExtensionScopedContext scoped(this);
   if (scoped.isLost())
@@ skipping 29 matching lines @@
         scoped.context()->synthesizeGLError(GL_INVALID_OPERATION,
                                             "drawBuffersWEBGL",
                                             "COLOR_ATTACHMENTi_EXT or NONE");
         return;
       }
     }
     scoped.context()->m_framebufferBinding->drawBuffers(buffers);
   }
 }
 
-// static
-bool WebGLDrawBuffers::satisfiesWebGLRequirements(
-    WebGLRenderingContextBase* webglContext) {
-  gpu::gles2::GLES2Interface* gl = webglContext->contextGL();
-  Extensions3DUtil* extensionsUtil = webglContext->extensionsUtil();
-
-  // This is called after we make sure GL_EXT_draw_buffers is supported.
-  GLint maxDrawBuffers = 0;
-  GLint maxColorAttachments = 0;
-  gl->GetIntegerv(GL_MAX_DRAW_BUFFERS_EXT, &maxDrawBuffers);
-  gl->GetIntegerv(GL_MAX_COLOR_ATTACHMENTS_EXT, &maxColorAttachments);
-  if (maxDrawBuffers < 4 || maxColorAttachments < 4)
-    return false;
-
-  GLuint fbo;
-  gl->GenFramebuffers(1, &fbo);
-  gl->BindFramebuffer(GL_FRAMEBUFFER, fbo);
-
-  const unsigned char* buffer =
-      0;  // Chromium doesn't allow init data for depth/stencil tetxures.
-  bool supportsDepth =
-      (extensionsUtil->supportsExtension("GL_CHROMIUM_depth_texture") ||
-       extensionsUtil->supportsExtension("GL_OES_depth_texture") ||
-       extensionsUtil->supportsExtension("GL_ARB_depth_texture"));
-  bool supportsDepthStencil =
-      (extensionsUtil->supportsExtension("GL_EXT_packed_depth_stencil") ||
-       extensionsUtil->supportsExtension("GL_OES_packed_depth_stencil"));
-  GLuint depthStencil = 0;
-  if (supportsDepthStencil) {
-    gl->GenTextures(1, &depthStencil);
-    gl->BindTexture(GL_TEXTURE_2D, depthStencil);
-    gl->TexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_STENCIL_OES, 1, 1, 0,
-                   GL_DEPTH_STENCIL_OES, GL_UNSIGNED_INT_24_8_OES, buffer);
-  }
-  GLuint depth = 0;
-  if (supportsDepth) {
-    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<GLuint> colors;
-  bool ok = true;
-  GLint maxAllowedBuffers = std::min(maxDrawBuffers, maxColorAttachments);
-  for (GLint i = 0; i < maxAllowedBuffers; ++i) {
-    GLuint color;
-
-    gl->GenTextures(1, &color);
-    colors.push_back(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) {
-      // For ES 2.0 contexts DEPTH_STENCIL is not available natively, so we
-      // emulate it at the command buffer level for WebGL contexts.
-      gl->FramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT,
-                               GL_TEXTURE_2D, depthStencil, 0);
-      if (gl->CheckFramebufferStatus(GL_FRAMEBUFFER) !=
-          GL_FRAMEBUFFER_COMPLETE) {
-        ok = false;
-        break;
-      }
-      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