#version 150

uniform sampler2D t0, ts, tg1;
uniform float radius = 2;
uniform vec2 dt;

vec4 getTexel(vec2 tc, vec4 fp, vec4 fps) {
	vec4 ct = max(texture(t0, tc), vec4(0)), st = max(texture(ts, tc), vec4(0));
	ct = mix(ct, fp, step(1, abs(fps.w - ct.w)));
	return ct;
}

void main(void) {
	ivec2 itc = ivec2(gl_FragCoord.xy);
	vec4 vg1 = texelFetch(tg1, itc, 0);
	vec2 tc = qgl_FragTexture.xy;
	float o = radius, o2 = radius * 2;
	vec4 fps = max(texture(ts, tc), vec4(0));
	vec4 fp = max(texture(t0, tc), vec4(0));
	vec4 scol = (fp * 3. +
				 getTexel(tc + dt * vec2(  o,  0 ), fp, fps) * 2. +
				 getTexel(tc + dt * vec2(  0,  o ), fp, fps) * 2. +
				 getTexel(tc + dt * vec2( -o, 0  ), fp, fps) * 2. +
				 getTexel(tc + dt * vec2(  0,  -o), fp, fps) * 2. +
				 getTexel(tc + dt * vec2(  o,  o ), fp, fps) * 1.5 +
				 getTexel(tc + dt * vec2(  o,  -o), fp, fps) * 1.5 +
				 getTexel(tc + dt * vec2( -o, -o ), fp, fps) * 1.5 +
				 getTexel(tc + dt * vec2( -o, o  ), fp, fps) * 1.5 +
				 getTexel(tc + dt * vec2( o2,  0 ), fp, fps) +
				 getTexel(tc + dt * vec2(  0,  o2), fp, fps) +
				 getTexel(tc + dt * vec2(-o2, 0  ), fp, fps) +
				 getTexel(tc + dt * vec2(  0, -o2), fp, fps)) / 21.;
	/*vec4 scol = fp;
	scol = min(scol, getTexel(tc + dt * vec2(  o,  0 ), fp, fps));
	scol = min(scol, getTexel(tc + dt * vec2(  0,  o ), fp, fps));
	scol = min(scol, getTexel(tc + dt * vec2( -o, 0  ), fp, fps));
	scol = min(scol, getTexel(tc + dt * vec2(  0,  -o), fp, fps));
	scol = min(scol, getTexel(tc + dt * vec2(  o,  o ), fp, fps));
	scol = min(scol, getTexel(tc + dt * vec2(  o,  -o), fp, fps));
	scol = min(scol, getTexel(tc + dt * vec2( -o, -o ), fp, fps));
	scol = min(scol, getTexel(tc + dt * vec2( -o, o  ), fp, fps));
	scol = min(scol, getTexel(tc + dt * vec2( o2,  0 ), fp, fps));
	scol = min(scol, getTexel(tc + dt * vec2(  0,  o2), fp, fps));
	scol = min(scol, getTexel(tc + dt * vec2(-o2, 0  ), fp, fps));
	scol = min(scol, getTexel(tc + dt * vec2(  0, -o2), fp, fps));*/
	qgl_FragData[0].rgba = vec4(vg1.z);
}