Bug 695912: implemented antialiasing blocklisting r=jgilbert

Antialiasing can be blocked through the downloaded blocklist now, as well as
static analysis compiled into the OS-specific handlers for graphics features.

content/canvas/src/WebGLContext.cpp

@@ -608,9 +608,14 @@ WebGLContext::SetDimensions(PRInt32 width, PRInt32 height)
         format.minAlpha = 0;
     }
 
-    if (mOptions.antialias) {
+    PRInt32 status;
-        PRUint32 msaaLevel = Preferences::GetUint("webgl.msaa-level", 2);
+    nsCOMPtr<nsIGfxInfo> gfxInfo = do_GetService("@mozilla.org/gfx/info;1");
-        format.samples = msaaLevel*msaaLevel;
+    if (mOptions.antialias && 
+        NS_SUCCEEDED(gfxInfo->GetFeatureStatus(nsIGfxInfo::FEATURE_WEBGL_MSAA, &status))) {
+        if (status == nsIGfxInfo::FEATURE_NO_INFO) {
+            PRUint32 msaaLevel = Preferences::GetUint("webgl.msaa-level", 2);
+            format.samples = msaaLevel*msaaLevel;
+        }
     }
 
     if (PR_GetEnv("MOZ_WEBGL_PREFER_EGL")) {
@@ -621,9 +626,7 @@ WebGLContext::SetDimensions(PRInt32 width, PRInt32 height)
     bool useOpenGL = true;
     bool useANGLE = true;
 
-    nsCOMPtr<nsIGfxInfo> gfxInfo = do_GetService("@mozilla.org/gfx/info;1");
     if (gfxInfo && !forceEnabled) {
-        PRInt32 status;
         if (NS_SUCCEEDED(gfxInfo->GetFeatureStatus(nsIGfxInfo::FEATURE_WEBGL_OPENGL, &status))) {
             if (status != nsIGfxInfo::FEATURE_NO_INFO) {
                 useOpenGL = false;

gfx/thebes/GLContextProviderCGL.mm

@@ -579,7 +579,6 @@ GLContextProviderCGL::CreateOffscreen(const gfxIntSize& aSize,
                                       const ContextFormat& aFormat)
 {
     ContextFormat actualFormat(aFormat);
-    actualFormat.samples = 0;
 
     nsRefPtr<GLContextCGL> glContext;
     

widget/public/nsIGfxInfo.idl

@@ -108,6 +108,8 @@ interface nsIGfxInfo : nsISupports
   const long FEATURE_WEBGL_OPENGL = 6;
   /* Whether WebGL is supported via ANGLE (D3D9 -- does not check for the presence of ANGLE libs). */
   const long FEATURE_WEBGL_ANGLE = 7;
+  /* Whether WebGL antialiasing is supported. */
+  const long FEATURE_WEBGL_MSAA = 8;
 
   /*
    * A set of return values from GetFeatureStatus

widget/src/cocoa/GfxInfo.mm

@@ -358,6 +358,12 @@ static GfxDriverInfo gDriverInfo[] = {
   //  GfxDriverInfo::vendorATI, GfxDriverInfo::allDevices,
   //  GfxDriverInfo::allFeatures, nsIGfxInfo::FEATURE_BLOCKED_OS_VERSION)
 
+  // Block all ATI cards from using MSAA, except for two devices that have
+  // special exceptions in the GetFeatureStatusImpl() function.
+  IMPLEMENT_MAC_DRIVER_BLOCKLIST(DRIVER_OS_ALL,
+    GfxDriverInfo::vendorATI, GfxDriverInfo::allDevices,
+    nsIGfxInfo::FEATURE_WEBGL_MSAA, nsIGfxInfo::FEATURE_BLOCKED_OS_VERSION)
+
   GfxDriverInfo()
 };
 
@@ -466,6 +472,16 @@ GfxInfo::GetFeatureStatusImpl(PRInt32 aFeature,
       status = nsIGfxInfo::FEATURE_BLOCKED_DEVICE;
   }
 
+  if (aFeature == nsIGfxInfo::FEATURE_WEBGL_MSAA) {
+    // Blacklist all ATI cards on OSX, except for
+    // 0x6760 and 0x9488
+    if (mAdapterVendorID == GfxDriverInfo::vendorATI && 
+          (mAdapterDeviceID == 0x6760 || mAdapterDeviceID == 0x9488)) {
+      *aStatus = nsIGfxInfo::FEATURE_NO_INFO;
+      return NS_OK;
+    }
+  }
+
   if (aOS)
     *aOS = os;
   *aStatus = status;

widget/src/xpwidgets/GfxInfoBase.cpp

@@ -157,6 +157,9 @@ GetPrefNameForFeature(PRInt32 aFeature)
     case nsIGfxInfo::FEATURE_WEBGL_ANGLE:
       name = BLACKLIST_PREF_BRANCH "webgl.angle";
       break;
+    case nsIGfxInfo::FEATURE_WEBGL_MSAA:
+      name = BLACKLIST_PREF_BRANCH "webgl.msaa";
+      break;
     default:
       break;
   };
@@ -315,6 +318,8 @@ BlacklistFeatureToGfxFeature(const nsAString& aFeature)
     return nsIGfxInfo::FEATURE_WEBGL_OPENGL;
   else if (aFeature == NS_LITERAL_STRING("WEBGL_ANGLE"))
     return nsIGfxInfo::FEATURE_WEBGL_ANGLE;
+  else if (aFeature == NS_LITERAL_STRING("WEBGL_MSAA"))
+    return nsIGfxInfo::FEATURE_WEBGL_MSAA;
 
   return 0;
 }
@@ -771,6 +776,7 @@ GfxInfoBase::EvaluateDownloadedBlacklist(nsTArray<GfxDriverInfo>& aDriverInfo)
     nsIGfxInfo::FEATURE_OPENGL_LAYERS,
     nsIGfxInfo::FEATURE_WEBGL_OPENGL,
     nsIGfxInfo::FEATURE_WEBGL_ANGLE,
+    nsIGfxInfo::FEATURE_WEBGL_MSAA,
     0
   };