precision lowp float;

uniform sampler2D Texture;
uniform sampler2D NormalMap;
uniform vec3 LightDirection;
varying vec2 texCoord;

varying vec3 camVec;
varying vec3 normVec;

void main() 
{

	vec3 cVec = normalize(camVec);
	
	float parallax = 0.035;

	//double refinement
	float height = texture2D(NormalMap, texCoord.xy).a;
	float offset = parallax * (2.0 * height - 1.0);
	vec2 parallaxTexCoord = texCoord.xy + offset * cVec.xy;
	height += texture2D(NormalMap, parallaxTexCoord).a;
	
	offset = parallax * (height - 1.0);
	
	parallaxTexCoord = texCoord.xy + offset * cVec.xy;
	
	vec3 nvec = normalize(normVec);
	
	
	float cosf = max(0.0, dot(nvec, -LightDirection));
	
	gl_FragColor =  vec4((texture2D(Texture, parallaxTexCoord).rgb * (cosf * 0.75 + 0.25)), 1.0);
}
