Use the desktop GL core profile on Linux when ES3 support is requested.

Request an OpenGL 4.2 context (the minimum version Chromium's WebGL
2.0 prototype currently requires) on Linux when
--enable-unsafe-es3-apis is specified on the command line.

Clean up the shader translator's selection of the GLSL output format.

BUG=471960

Review URL: https://codereview.chromium.org/1052153002

Cr-Commit-Position: refs/heads/master@{#323658}

9 files changed, 65 insertions, 32 deletions

diff --git a/gpu/command_buffer/service/async_pixel_transfer_manager_linux.cc b/gpu/command_buffer/service/async_pixel_transfer_manager_linux.cc
index b0cc463..4afe77c1 100644
--- a/gpu/command_buffer/service/async_pixel_transfer_manager_linux.cc
+++ b/gpu/command_buffer/service/async_pixel_transfer_manager_linux.cc
@@ -27,6 +27,7 @@ AsyncPixelTransferManager* AsyncPixelTransferManager::Create(
   switch (gfx::GetGLImplementation()) {
     case gfx::kGLImplementationOSMesaGL:
     case gfx::kGLImplementationDesktopGL:
+    case gfx::kGLImplementationDesktopGLCoreProfile:
     case gfx::kGLImplementationEGLGLES2:
       return new AsyncPixelTransferManagerIdle(true);
     case gfx::kGLImplementationMockGL:
diff --git a/gpu/command_buffer/service/gles2_cmd_decoder.cc b/gpu/command_buffer/service/gles2_cmd_decoder.cc
index d402c93..d1d1d9c 100644
--- a/gpu/command_buffer/service/gles2_cmd_decoder.cc
+++ b/gpu/command_buffer/service/gles2_cmd_decoder.cc
@@ -1690,6 +1690,10 @@ class GLES2DecoderImpl : public GLES2Decoder,
     return feature_info_->workarounds();
   }
 
+  const gfx::GLVersionInfo& gl_version() const {
+    return feature_info_->gl_version_info();
+  }
+
   bool ShouldDeferDraws() {
     return !offscreen_target_frame_buffer_.get() &&
            framebuffer_state_.bound_draw_framebuffer.get() == NULL &&
@@ -2739,7 +2743,7 @@ bool GLES2DecoderImpl::Initialize(
 
       bool default_fb = (GetBackbufferServiceId() == 0);
 
-      if (feature_info_->gl_version_info().is_desktop_core_profile) {
+      if (gl_version().is_desktop_core_profile) {
         glGetFramebufferAttachmentParameterivEXT(
             GL_FRAMEBUFFER,
             default_fb ? GL_BACK_LEFT : GL_COLOR_ATTACHMENT0,
@@ -2778,7 +2782,7 @@ bool GLES2DecoderImpl::Initialize(
   // mailing list archives. It also implicitly enables the desktop GL
   // capability GL_POINT_SPRITE to provide access to the gl_PointCoord
   // variable in fragment shaders.
-  if (!feature_info_->gl_version_info().BehavesLikeGLES()) {
+  if (!gl_version().BehavesLikeGLES()) {
     glEnable(GL_VERTEX_PROGRAM_POINT_SIZE);
     glEnable(GL_POINT_SPRITE);
   }
@@ -3016,8 +3020,11 @@ bool GLES2DecoderImpl::InitializeShaderTranslator() {
   else
     resources.HashFunction = NULL;
   ShaderTranslatorInterface::GlslImplementationType implementation_type =
-      gfx::GetGLImplementation() == gfx::kGLImplementationEGLGLES2 ?
-          ShaderTranslatorInterface::kGlslES : ShaderTranslatorInterface::kGlsl;
+      ShaderTranslatorInterface::kGlsl;
+  if (gl_version().is_es)
+    implementation_type = ShaderTranslatorInterface::kGlslES;
+  else if (gl_version().is_desktop_core_profile)
+    implementation_type = ShaderTranslatorInterface::kGlslCoreProfile;
   int driver_bug_workarounds = 0;
   if (workarounds().needs_glsl_built_in_function_emulation)
     driver_bug_workarounds |= SH_EMULATE_BUILT_IN_FUNCTIONS;
@@ -4589,7 +4596,7 @@ void GLES2DecoderImpl::DoDiscardFramebufferEXT(GLenum target,
   }
 
   ScopedRenderTo do_render(framebuffer);
-  if (feature_info_->gl_version_info().is_es3) {
+  if (gl_version().is_es3) {
     glInvalidateFramebuffer(
         target, numAttachments, translated_attachments.get());
   } else {
@@ -4771,7 +4778,7 @@ bool GLES2DecoderImpl::GetHelper(
       *num_written = 1;
       if (params) {
         GLint v = 0;
-        if (feature_info_->gl_version_info().is_desktop_core_profile) {
+        if (gl_version().is_desktop_core_profile) {
           Framebuffer* framebuffer =
               GetFramebufferInfoForTarget(GL_DRAW_FRAMEBUFFER_EXT);
           if (framebuffer) {
@@ -4792,7 +4799,7 @@ bool GLES2DecoderImpl::GetHelper(
       *num_written = 1;
       if (params) {
         GLint v = 0;
-        if (feature_info_->gl_version_info().is_desktop_core_profile) {
+        if (gl_version().is_desktop_core_profile) {
           Framebuffer* framebuffer =
               GetFramebufferInfoForTarget(GL_DRAW_FRAMEBUFFER_EXT);
           if (framebuffer) {
@@ -4814,7 +4821,7 @@ bool GLES2DecoderImpl::GetHelper(
       *num_written = 1;
       if (params) {
         GLint v = 0;
-        if (feature_info_->gl_version_info().is_desktop_core_profile) {
+        if (gl_version().is_desktop_core_profile) {
           Framebuffer* framebuffer =
               GetFramebufferInfoForTarget(GL_DRAW_FRAMEBUFFER_EXT);
           if (framebuffer) {
@@ -4845,7 +4852,7 @@ bool GLES2DecoderImpl::GetHelper(
       *num_written = 1;
       if (params) {
         GLint v = 0;
-        if (feature_info_->gl_version_info().is_desktop_core_profile) {
+        if (gl_version().is_desktop_core_profile) {
           Framebuffer* framebuffer =
               GetFramebufferInfoForTarget(GL_DRAW_FRAMEBUFFER_EXT);
           if (framebuffer) {
@@ -5689,7 +5696,7 @@ void GLES2DecoderImpl::BlitFramebufferHelper(GLint srcX0,
                                              GLenum filter) {
   // TODO(sievers): This could be resolved at the GL binding level, but the
   // binding process is currently a bit too 'brute force'.
-  if (feature_info_->gl_version_info().is_angle) {
+  if (gl_version().is_angle) {
     glBlitFramebufferANGLE(
         srcX0, srcY0, srcX1, srcY1, dstX0, dstY0, dstX1, dstY1, mask, filter);
   } else if (feature_info_->feature_flags().use_core_framebuffer_multisample) {
@@ -6704,7 +6711,7 @@ bool GLES2DecoderImpl::SimulateAttrib0(
   DCHECK(simulated);
   *simulated = false;
 
-  if (feature_info_->gl_version_info().BehavesLikeGLES())
+  if (gl_version().BehavesLikeGLES())
     return true;
 
   const VertexAttrib* attrib =
@@ -8061,7 +8068,7 @@ error::Error GLES2DecoderImpl::HandleReadPixels(uint32 immediate_data_size,
       glGenBuffersARB(1, &buffer);
       glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, buffer);
       // For ANGLE client version 2, GL_STREAM_READ is not available.
-      const GLenum usage_hint = feature_info_->gl_version_info().is_angle ?
+      const GLenum usage_hint = gl_version().is_angle ?
           GL_STATIC_DRAW : GL_STREAM_READ;
       glBufferData(GL_PIXEL_PACK_BUFFER_ARB, pixels_size, NULL, usage_hint);
       GLenum error = glGetError();
@@ -10293,7 +10300,7 @@ void GLES2DecoderImpl::DoSwapBuffers() {
       // Ensure the side effects of the copy are visible to the parent
       // context. There is no need to do this for ANGLE because it uses a
       // single D3D device for all contexts.
-      if (!feature_info_->gl_version_info().is_angle)
+      if (!gl_version().is_angle)
         glFlush();
     }
   } else {
diff --git a/gpu/command_buffer/service/shader_translator.cc b/gpu/command_buffer/service/shader_translator.cc
index b4a94fc..bc8b1fa 100644
--- a/gpu/command_buffer/service/shader_translator.cc
+++ b/gpu/command_buffer/service/shader_translator.cc
@@ -117,19 +117,20 @@ bool ShaderTranslator::Init(
 
   g_translator_initializer.Get();
 
-  ShShaderOutput shader_output;
-  if (glsl_implementation_type == kGlslES) {
-    shader_output = SH_ESSL_OUTPUT;
-  } else {
-    // TODO(kbr): clean up the tests of shader_spec and
-    // gfx::GetGLImplementation(). crbug.com/471960
-    if (shader_spec == SH_WEBGL2_SPEC ||
-        gfx::GetGLImplementation() ==
-            gfx::kGLImplementationDesktopGLCoreProfile) {
-      shader_output = SH_GLSL_CORE_OUTPUT;
-    } else {
+  ShShaderOutput shader_output = SH_ESSL_OUTPUT;
+  switch (glsl_implementation_type) {
+    case kGlsl:
       shader_output = SH_GLSL_COMPATIBILITY_OUTPUT;
-    }
+      break;
+    case kGlslCoreProfile:
+      shader_output = SH_GLSL_CORE_OUTPUT;
+      break;
+    case kGlslES:
+      // Handled in initialization above.
+      break;
+    default:
+      NOTREACHED();
+      break;
   }
 
   {
diff --git a/gpu/command_buffer/service/shader_translator.h b/gpu/command_buffer/service/shader_translator.h
index 818be5d..68aa1d9 100644
--- a/gpu/command_buffer/service/shader_translator.h
+++ b/gpu/command_buffer/service/shader_translator.h
@@ -33,6 +33,7 @@ class ShaderTranslatorInterface
   ShaderTranslatorInterface() {}
   enum GlslImplementationType {
     kGlsl,
+    kGlslCoreProfile,
     kGlslES
   };
 
diff --git a/gpu/config/gpu_info_collector.cc b/gpu/config/gpu_info_collector.cc
index 521f2cd..e9d60b1 100644
--- a/gpu/config/gpu_info_collector.cc
+++ b/gpu/config/gpu_info_collector.cc
@@ -98,7 +98,7 @@ CollectInfoResult CollectGraphicsInfoGL(GPUInfo* gpu_info) {
 
   gpu_info->gl_renderer = GetGLString(GL_RENDERER);
   gpu_info->gl_vendor = GetGLString(GL_VENDOR);
-  gpu_info->gl_extensions = GetGLString(GL_EXTENSIONS);
+  gpu_info->gl_extensions = context->GetExtensions();
   gpu_info->gl_version = GetGLString(GL_VERSION);
   std::string glsl_version_string = GetGLString(GL_SHADING_LANGUAGE_VERSION);
 
diff --git a/ui/gl/gl_context_glx.cc b/ui/gl/gl_context_glx.cc
index e5b1cc1..b7d7e21 100644
--- a/ui/gl/gl_context_glx.cc
+++ b/ui/gl/gl_context_glx.cc
@@ -38,6 +38,18 @@ bool GLContextGLX::Initialize(
   if (GLSurfaceGLX::IsCreateContextSupported()) {
     DVLOG(1) << "GLX_ARB_create_context supported.";
     std::vector<int> attribs;
+    if (gfx::GetGLImplementation() ==
+        gfx::kGLImplementationDesktopGLCoreProfile) {
+      // TODO(kbr): NVIDIA's driver doesn't return a later context
+      // version if any version later than 3.1 is requested. We
+      // explicitly want to request a 3.2+ context with no support for
+      // the compatibility profile. WebGL 2.0 support currently
+      // requires a 4.2 context. crbug.com/473427
+      attribs.push_back(GLX_CONTEXT_MAJOR_VERSION_ARB);
+      attribs.push_back(4);
+      attribs.push_back(GLX_CONTEXT_MINOR_VERSION_ARB);
+      attribs.push_back(2);
+    }
     if (GLSurfaceGLX::IsCreateContextRobustnessSupported()) {
       DVLOG(1) << "GLX_ARB_create_context_robustness supported.";
       attribs.push_back(GLX_CONTEXT_RESET_NOTIFICATION_STRATEGY_ARB);
diff --git a/ui/gl/gl_context_x11.cc b/ui/gl/gl_context_x11.cc
index b17364d..dd5e3b8 100644
--- a/ui/gl/gl_context_x11.cc
+++ b/ui/gl/gl_context_x11.cc
@@ -35,7 +35,8 @@ scoped_refptr<GLContext> GLContext::CreateGLContext(
 
       return context;
     }
-    case kGLImplementationDesktopGL: {
+    case kGLImplementationDesktopGL:
+    case kGLImplementationDesktopGLCoreProfile: {
       scoped_refptr<GLContext> context(new GLContextGLX(share_group));
       if (!context->Initialize(compatible_surface, gpu_preference))
         return NULL;
diff --git a/ui/gl/gl_implementation_x11.cc b/ui/gl/gl_implementation_x11.cc
index b8a7246..32fd369 100644
--- a/ui/gl/gl_implementation_x11.cc
+++ b/ui/gl/gl_implementation_x11.cc
@@ -43,6 +43,10 @@ const char kEGLLibraryName[] = "libEGL.so.1";
 }  // namespace
 
 void GetAllowedGLImplementations(std::vector<GLImplementation>* impls) {
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableUnsafeES3APIs)) {
+    impls->push_back(kGLImplementationDesktopGLCoreProfile);
+  }
   impls->push_back(kGLImplementationDesktopGL);
   impls->push_back(kGLImplementationEGLGLES2);
   impls->push_back(kGLImplementationOSMesaGL);
@@ -63,7 +67,8 @@ bool InitializeStaticGLBindings(GLImplementation implementation) {
   switch (implementation) {
     case kGLImplementationOSMesaGL:
       return InitializeStaticGLBindingsOSMesaGL();
-    case kGLImplementationDesktopGL: {
+    case kGLImplementationDesktopGL:
+    case kGLImplementationDesktopGLCoreProfile: {
       base::NativeLibrary library = NULL;
       const base::CommandLine* command_line =
           base::CommandLine::ForCurrentProcess();
@@ -91,7 +96,7 @@ bool InitializeStaticGLBindings(GLImplementation implementation) {
 
       SetGLGetProcAddressProc(get_proc_address);
       AddGLNativeLibrary(library);
-      SetGLImplementation(kGLImplementationDesktopGL);
+      SetGLImplementation(implementation);
 
       InitializeStaticGLBindingsGL();
       InitializeStaticGLBindingsGLX();
@@ -151,7 +156,8 @@ bool InitializeDynamicGLBindings(GLImplementation implementation,
     GLContext* context) {
   switch (implementation) {
     case kGLImplementationOSMesaGL:
-   case kGLImplementationDesktopGL:
+    case kGLImplementationDesktopGL:
+    case kGLImplementationDesktopGLCoreProfile:
     case kGLImplementationEGLGLES2:
       InitializeDynamicGLBindingsGL(context);
       break;
@@ -191,6 +197,7 @@ void ClearGLBindings() {
 bool GetGLWindowSystemBindingInfo(GLWindowSystemBindingInfo* info) {
   switch (GetGLImplementation()) {
     case kGLImplementationDesktopGL:
+    case kGLImplementationDesktopGLCoreProfile:
       return GetGLWindowSystemBindingInfoGLX(info);
     case kGLImplementationEGLGLES2:
       return GetGLWindowSystemBindingInfoEGL(info);
diff --git a/ui/gl/gl_surface_x11.cc b/ui/gl/gl_surface_x11.cc
index a384147..63b0e96 100644
--- a/ui/gl/gl_surface_x11.cc
+++ b/ui/gl/gl_surface_x11.cc
@@ -52,6 +52,7 @@ class NativeViewGLSurfaceOSMesa : public GLSurfaceOSMesa {
 bool GLSurface::InitializeOneOffInternal() {
   switch (GetGLImplementation()) {
     case kGLImplementationDesktopGL:
+    case kGLImplementationDesktopGLCoreProfile:
       if (!GLSurfaceGLX::InitializeOneOff()) {
         LOG(ERROR) << "GLSurfaceGLX::InitializeOneOff failed.";
         return false;
@@ -283,7 +284,8 @@ scoped_refptr<GLSurface> GLSurface::CreateViewGLSurface(
 
       return surface;
     }
-    case kGLImplementationDesktopGL: {
+    case kGLImplementationDesktopGL:
+    case kGLImplementationDesktopGLCoreProfile: {
       scoped_refptr<GLSurface> surface(new NativeViewGLSurfaceGLX(window));
       if (!surface->Initialize())
         return NULL;
@@ -318,7 +320,8 @@ scoped_refptr<GLSurface> GLSurface::CreateOffscreenGLSurface(
 
       return surface;
     }
-    case kGLImplementationDesktopGL: {
+    case kGLImplementationDesktopGL:
+    case kGLImplementationDesktopGLCoreProfile: {
       scoped_refptr<GLSurface> surface(new PbufferGLSurfaceGLX(size));
       if (!surface->Initialize())
         return NULL;