stk-code_catmod/data/shaders/normalmap.frag

uniform sampler2D normalMap;

#if __VERSION__ >= 130
in vec3 tangent;
in vec3 bitangent;
in vec2 uv;
out vec2 EncodedNormal;
#else
varying vec3 tangent;
varying vec3 bitangent;
varying vec2 uv;
#define EncodedNormal gl_FragColor.xy
#endif



vec2 EncodeNormal(vec3 n);

void main()
{
	// normal in Tangent Space
	vec3 TS_normal = 2.0 * pow(texture(normalMap, uv).rgb, vec3(1./2.2)) - 1.0;
	// Because of interpolation, we need to renormalize
	vec3 Frag_tangent = normalize(tangent);
	vec3 Frag_normal = normalize(cross(Frag_tangent, bitangent));
	vec3 Frag_bitangent = cross(Frag_normal, Frag_tangent);

	vec3 FragmentNormal = TS_normal.x * Frag_tangent + TS_normal.y * Frag_bitangent - TS_normal.z * Frag_normal;	
	EncodedNormal = 0.5 * EncodeNormal(normalize(FragmentNormal)) + 0.5;
}