A basic test (TODO, if this is accepted I should make a new shader for only this effect

git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@14601 178a84e3-b1eb-0310-8ba1-8eac791a3b58

data/shaders/flip.frag

@@ -5,5 +5,13 @@ void main()
 	vec2 texc = gl_TexCoord[0].xy;
 	texc.y = 1.0 - texc.y;
 
-	gl_FragColor = texture2D(tex, texc);
+
+	vec4 col = texture2D(tex, texc);
+	
+	//col = col * 256;
+	//col = (1 - col);
+	
+	col = col / (1 - col);
+	
+	gl_FragColor = vec4(col.rgb, 1.0);
 }