2 files changed, 23 insertions, 0 deletions
diff --git a/src/classes/com/sun/opengl/impl/x11/X11GLContext.java b/src/classes/com/sun/opengl/impl/x11/X11GLContext.java
index b6c4fbfcd..0ed5eaebb 100644
--- a/src/classes/com/sun/opengl/impl/x11/X11GLContext.java
+++ b/src/classes/com/sun/opengl/impl/x11/X11GLContext.java
@@ -298,6 +298,11 @@ public abstract class X11GLContext extends GLContextImpl {
     throw new GLException("Should not call this");
   }
 
+  public boolean isOptimizable() {
+    return (super.isOptimizable() &&
+            !X11GLDrawableFactory.getX11Factory().isVendorATI());
+  }
+
   //----------------------------------------------------------------------
   // Internals only below this point
   //
diff --git a/src/classes/com/sun/opengl/impl/x11/X11GLDrawableFactory.java b/src/classes/com/sun/opengl/impl/x11/X11GLDrawableFactory.java
index 257fdab6e..9ba591e5f 100644
--- a/src/classes/com/sun/opengl/impl/x11/X11GLDrawableFactory.java
+++ b/src/classes/com/sun/opengl/impl/x11/X11GLDrawableFactory.java
@@ -56,6 +56,11 @@ public class X11GLDrawableFactory extends GLDrawableFactoryImpl {
   // There is currently a bug on Linux/AMD64 distributions in glXGetProcAddressARB
   private static boolean isLinuxAMD64;
 
+  // ATI's proprietary drivers apparently send GLX tokens even for
+  // direct contexts, so we need to disable the context optimizations
+  // in this case
+  private static boolean isVendorATI;
+
   static {
     // See DRIHack.java for an explanation of why this is necessary
     DRIHack.begin();
@@ -444,6 +449,13 @@ public class X11GLDrawableFactory extends GLDrawableFactoryImpl {
           System.err.println("!!! GLX client version: " +
                              GLX.glXGetClientString(display, GLX.GLX_VERSION));
         }
+
+        if (staticDisplay != 0) {
+          String vendor = GLX.glXGetClientString(staticDisplay, GLX.GLX_VENDOR);
+          if (vendor != null && vendor.startsWith("ATI")) {
+            isVendorATI = true;
+          }
+        }
       } finally {
         getX11Factory().unlockToolkit();
       }
@@ -493,6 +505,12 @@ public class X11GLDrawableFactory extends GLDrawableFactoryImpl {
     return (X11GLDrawableFactory) getFactory();
   }
 
+  /** Workaround for apparent issue with ATI's proprietary drivers
+      where direct contexts still send GLX tokens for GL calls */
+  public static boolean isVendorATI() {
+    return isVendorATI;
+  }
+
   private void maybeDoSingleThreadedWorkaround(Runnable action) {
     if (Threading.isSingleThreaded() &&
         !Threading.isOpenGLThread()) {