// AA shader v1.0
// by guest(r)
// license: GNU-GPL

uniform sampler2D OGL2Texture;

void main()
{
	vec3 c00 = texture2D(OGL2Texture, gl_TexCoord[5].xy).xyz; 
	vec3 c10 = texture2D(OGL2Texture, gl_TexCoord[1].xy).xyz; 
	vec3 c20 = texture2D(OGL2Texture, gl_TexCoord[2].zw).xyz; 
	vec3 c01 = texture2D(OGL2Texture, gl_TexCoord[3].xy).xyz; 
	vec3 c11 = texture2D(OGL2Texture, gl_TexCoord[0].xy).xyz; 
	vec3 c21 = texture2D(OGL2Texture, gl_TexCoord[4].xy).xyz; 
	vec3 c02 = texture2D(OGL2Texture, gl_TexCoord[1].zw).xyz; 
	vec3 c12 = texture2D(OGL2Texture, gl_TexCoord[2].xy).xyz; 
	vec3 c22 = texture2D(OGL2Texture, gl_TexCoord[6].xy).xyz; 
	vec3 dt = vec3(1.0,1.0,1.0); 

	float d1=dot(abs(c00-c22),dt)+0.001;
	float d2=dot(abs(c20-c02),dt)+0.001;
	float hl=dot(abs(c01-c21),dt)+0.001;
	float vl=dot(abs(c10-c12),dt)+0.001;
	
	float k1=0.5*(hl+vl);
	float k2=0.5*(d1+d2);
	
	vec3 t1 = (hl*(c10+c12) + vl*(c01+c21) + k1*c11)/(2.5*(hl+vl));
	vec3 t2 = (d1*(c20+c02) + d2*(c00+c22) + k2*c11)/(2.5*(d1+d2));

	k1 = dot(abs(t1-c11),dt) + 0.001; k1*=k1;
	k2 = dot(abs(t2-c11),dt) + 0.001; k2*=k2;
	
	gl_FragColor.xyz = (k1*t2 + k2*t1)/(k1+k2);
}