// imitation of the Unreal Engine 1.x ambient glow effect
// plus brightmapping
vec4 ProcessLight( vec4 color )
{
	float bright = texture(brighttex,vTexCoord.st).x;
	vec2 gs = texture(ambglow,vec2(.5)).xy;
	if ( gs.x > .5 ) return vec4(min(color.rgb+vec3(bright),1.0),color.a);
	if ( gs.y > .5 )
	{
		float glow = max(0.,sin(timer*4)-.5);
		return vec4(min(color.rgb+vec3(bright)+vec3(glow),1.),color.a);
	}
	float glow = 0.25+0.2*sin(timer*8);
	return vec4(min(color.rgb+vec3(bright)+vec3(glow),1.0),color.a);
}

vec4 ProcessTexel()
{
	vec2 gs = texture(ambglow,vec2(.5)).xy;
	if ( gs.x > .5 ) getTexel(vTexCoord.st);
	if ( gs.y > .5 )
	{
		float glow = max(0.,sin(timer*4)-.5);
		vec4 col = getTexel(vTexCoord.st);
		return vec4(min(col.rgb+vec3(glow),1.),col.a);
	}
	return getTexel(vTexCoord.st);
}