Removing Xgl support from KWin.

Xgl has been removed from the X tree in 2008. It does not make sense
to still support it in KWin.

compositingprefs.cpp

@@ -36,8 +36,7 @@ namespace KWin
 {
 
 CompositingPrefs::CompositingPrefs()
-    : mXgl( false )
-    , mRecommendCompositing( false )
+    : mRecommendCompositing( false )
     , mEnableVSync( true )
     , mEnableDirectRendering( true )
     , mStrictBinding( true )
@@ -348,11 +347,6 @@ void CompositingPrefs::detectDriverAndVersion()
     GLPlatform *gl = GLPlatform::instance();
     gl->detect();
     gl->printResults();
-
-    mXgl = detectXgl();
-
-    if( mXgl )
-        kWarning( 1212 ) << "Using XGL";
 #endif
     }
 
@@ -370,11 +364,5 @@ void CompositingPrefs::applyDriverSpecificOptions()
 #endif
     }
 
-
-bool CompositingPrefs::detectXgl()
-    { // Xgl apparently uses only this specific X version
-    return VendorRelease(display()) == 70000001;
-    }
-
 } // namespace
 

compositingprefs.h

@@ -46,13 +46,10 @@ public:
 
     void detect();
 
-    bool xgl() const { return mXgl; }
-
 protected:
 
     void detectDriverAndVersion();
     void applyDriverSpecificOptions();
-    static bool detectXgl();
 
     bool initGLXContext();
     void deleteGLXContext();
@@ -61,8 +58,6 @@ protected:
 
 
 private:
-    bool mXgl;
-
     bool mRecommendCompositing;
     bool mEnableVSync;
     bool mEnableDirectRendering;

scene_opengl_glx.cpp

@@ -726,18 +726,6 @@ void SceneOpenGL::Texture::findTarget()
     unsigned int new_target = 0;
     if( tfp_mode && glXQueryDrawable && glxpixmap != None )
         glXQueryDrawable( display(), glxpixmap, GLX_TEXTURE_TARGET_EXT, &new_target );
-    // Hack for XGL - this should not be a fallback for glXQueryDrawable() but instead the case
-    // when glXQueryDrawable is not available. However this call fails with XGL, unless KWin
-    // is compiled statically with the libGL that Compiz is built against (without which neither
-    // Compiz works with XGL). Falling back to doing this manually makes this work.
-    if( new_target == 0 )
-        {
-        if( NPOTTextureSupported() ||
-            ( isPowerOfTwo( mSize.width()) && isPowerOfTwo( mSize.height())))
-            new_target = GLX_TEXTURE_2D_EXT;
-        else
-            new_target = GLX_TEXTURE_RECTANGLE_EXT;
-        }
     switch( new_target )
         {
         case GLX_TEXTURE_2D_EXT: