Kirill: Fixed Mac issue where canvas wouldn't render anything when framebuffers were used

git-svn-id: https://jmonkeyengine.googlecode.com/svn/trunk@7447 75d07b2b-3a1a-0410-a2c5-0572b91ccdca

engine/src/lwjgl-ogl/com/jme3/renderer/lwjgl/LwjglRenderer.java

@@ -202,8 +202,14 @@ public class LwjglRenderer implements Renderer {
 
         // Fix issue in TestRenderToMemory when GL_FRONT is the main
         // buffer being used.
-        initialDrawBuf = glGetInteger(GL_DRAW_BUFFER);
+//        initialDrawBuf = glGetInteger(GL_DRAW_BUFFER);
-        initialReadBuf = glGetInteger(GL_READ_BUFFER);
+//        initialReadBuf = glGetInteger(GL_READ_BUFFER);
+        
+        // XXX: This has to be GL_BACK for canvas on Mac
+        // Since initialDrawBuf is GL_FRONT for pbuffer, gotta
+        // change this value later on ...
+        initialDrawBuf = GL_BACK;
+        initialReadBuf = GL_BACK;
 
         int spaceIdx = versionStr.indexOf(" ");
         if (spaceIdx >= 1) {