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

// imitation of the Unreal Engine 1.x bMeshEnviroMap effect, not 1:1 but gets close
// with the addition of a mask for blending the environment map with the base texture
vec4 ProcessTexel()
{
	vec4 base = getTexel(vTexCoord.st);
	float mask = texture(masktex,vTexCoord.st).x;
	vec3 eyedir = normalize(uCameraPos.xyz-pixelpos.xyz);
	vec3 norm = reflect(eyedir,normalize(vWorldNormal.xyz));
	vec2 gs = texture(ambglow,vec2(.5)).xy;
	if ( gs.x > .5 ) return vec4(base.rgb+texture(envtex,norm.xz*0.5+0.5).rgb*mask,base.a);
	if ( gs.y > .5 )
	{
		float glow = max(0.,sin(timer*4)-.5);
		vec3 col = base.rgb+texture(envtex,norm.xz*0.5+0.5).rgb*mask;
		return vec4(min(col+vec3(glow),1.),base.a);
	}
	return vec4(base.rgb+texture(envtex,norm.xz*0.5+0.5).rgb*mask,base.a);
}