* some linux fixes

uglcContextGtk2GLX.pas

@@ -60,10 +60,7 @@ type
 
 {$region messages -fold}
 procedure TRenderControl.WndProc(var Message: TLMessage);
-var
-  handled: Boolean;
 begin
-  handled := false;
   case Message.msg of
     //LM_ACTIVATEITEM,
     //LM_CHANGED,
@@ -269,10 +266,8 @@ begin
     CN_SYSCHAR,
     CN_NOTIFY:
     begin
-      if Assigned(fTarget) then begin
+      if Assigned(fTarget) then
         Message.Result := fTarget.Perform(Message.msg, Message.wParam, Message.lParam);
-        handled := true;
-      end;
     end;
   end;
   inherited WndProc(Message);
@@ -422,6 +417,7 @@ procedure TglcContextGtk2GLX.OpenContext;
 var
   Attribs: array of GLint;
   tmpContext: GLXContext;
+  glxID: GLXDrawable;
 begin
   inherited OpenContext;
 
@@ -453,7 +449,8 @@ begin
     SetLength(Attribs, 1);
     Attribs[High(Attribs)] := 0;
 
-    glXMakeCurrent(FDisplay, GDK_DRAWABLE_XID(GTK_WIDGET(FWidget)^.window), tmpContext);
+    glxID := GDK_DRAWABLE_XID(GTK_WIDGET(FWidget)^.window);
+    glXMakeCurrent(FDisplay, glxID, tmpContext);
     ReadImplementationProperties;
     if not Assigned(glXCreateContextAttribsARB) or not GLX_ARB_create_context then begin
       glXDestroyContext(FDisplay, tmpContext);
@@ -500,6 +497,8 @@ begin
 end;
 
 procedure TglcContextGtk2GLX.Activate;
+var
+   glxID: GLXDrawable;
 begin
   if not Assigned(FWidget) then exit;
   // make sure the widget is realized
@@ -507,30 +506,36 @@ begin
   if not GTK_WIDGET_REALIZED(FWidget) then exit;
 
   // make current
-
-  glXMakeCurrent(FDisplay, GDK_DRAWABLE_XID(GTK_WIDGET(FWidget)^.window), FContext);
+  glxID := GDK_DRAWABLE_XID(GTK_WIDGET(FWidget)^.window);
+  glXMakeCurrent(FDisplay, glxID, FContext);
 end;
 
 procedure TglcContextGtk2GLX.Deactivate;
+var
+   glxID: GLXDrawable;
 begin
   if not Assigned(FWidget) then exit;
-  glXMakeCurrent(FDisplay, GDK_DRAWABLE_XID(GTK_WIDGET(FWidget)^.window), nil);
+  glxID := GDK_DRAWABLE_XID(GTK_WIDGET(FWidget)^.window);
+  glXMakeCurrent(FDisplay, glxID, nil);
 end;
 
 function TglcContextGtk2GLX.IsActive: boolean;
+var
+  glxID: GLXDrawable;
 begin
+  glxID := GDK_DRAWABLE_XID(GTK_WIDGET(FWidget)^.window);
   Result:= (FContext = glXGetCurrentContext()) and
            Assigned(FWidget) and
-           (GDK_DRAWABLE_XID(GTK_WIDGET(FWidget)^.window) = glXGetCurrentDrawable());
+           (glxID = glXGetCurrentDrawable());
 end;
 
 procedure TglcContextGtk2GLX.SwapBuffers;
 var
-  drawable: PGdkDrawable;
+  glxID: GLXDrawable;
 begin
   if not Assigned(FWidget) then exit;
-  drawable:= GTK_WIDGET(FWidget)^.window;
-  glXSwapBuffers(FDisplay, GDK_DRAWABLE_XID(drawable));
+  glxID := GDK_DRAWABLE_XID(GTK_WIDGET(FWidget)^.window);
+  glXSwapBuffers(FDisplay, glxID);
 end;
 
 procedure TglcContextGtk2GLX.SetSwapInterval(const aInterval: GLint);
@@ -547,7 +552,7 @@ begin
   raise Exception.Create('not yet implemented');
 end;
 
-class function TglcContextGtk2GLX.ChangeDisplaySettings(const aWidth, aHeight,
+class function TglcContextGtk2GLX.{%H-}ChangeDisplaySettings(const aWidth, aHeight,
   aBitPerPixel, aFreq: Integer; const aFlags: TglcDisplayFlags): Boolean;
 begin
   raise Exception.Create('not yet implemented');
@@ -559,4 +564,4 @@ begin
 end;
 
 end.
-
+