#version 450 core
//! type fragment

//! include chunks/raymarcher.glsl
//! include lib/shading-pbr.glsl
//! include lib/shading-blinnphong.glsl


T_BPMaterial BPMaterials[1] = {
	{ vec3( 1 , 1 , .4 ) * .1 , vec3( 1 , 1 , .4 ) , 40 , .1 }
};

T_PBRMaterial PBRMaterials[1] = {
	{
		// Albedo color
		vec3( 1 , 1 , .4 ) ,
		// Roughness , metallic , subsurface , anisotropy
		.4 , .7 , 1 , .1 ,
		// Specular strength / tint%
		.5 , .5
	}
};

vec3 Glow[1] = {
	vec3( 2 , .4 , 5 ) * 4
};

void mapMaterial(
	in int matIndex ,
	out int type ,
	out int tIndex ,
	out int glowIndex )
{
	if ( matIndex == 0 ) {
		glowIndex = -1;
	} else {
		//type = 1;
		glowIndex = 0;
	}
	type = 1;
	tIndex = 0;
}

vec2 RM_Map( vec3 pos )
{
	pos = pos - vec3( 0 , 0 , 0 );
	vec3 q = pos;
	q.xy = mod( q.xy + 4. , 8. ) - 4.;
	return vec2( length( q ) - 1.8 , step( 0. , 1.9 - length( pos.xy ) ) );
}


void main( )
{
	vec2 uv = ( gl_FragCoord.xy / u_Resolution ) * 2 - 1;
	vec3 camDir = normalize( u_LookAt - u_CamPos );
	vec3 side = normalize( cross( u_CamUp , camDir ) );
	vec3 up = normalize( cross( camDir , side ) );
	vec3 rayDir = normalize( camDir * u_NearPlane
			+ uv.x * side * u_Resolution.x / u_Resolution.y
			+ uv.y * up );

	vec3 r = RM_Advanced( u_CamPos , rayDir ,
			int( u_Render.x ) , u_Render.y ,
			u_Render.z , .001 , u_Render.w );
	vec3 hitPos = u_CamPos + rayDir * r.x;

	vec3 bc = vec3( 0 );
	if ( r.y >= 0. ) {
		const int midx = int( r.y );
		const vec3 normal = RM_GetNormal( hitPos );
		const vec3 lightDir = normalize( -u_LightDir );

		// Remap materials through mapMaterials
		int mtype , mtidx , glowidx;
		mapMaterial( midx , mtype , mtidx , glowidx );
		if ( mtype == 0 ) {
			bc = BP_Shade( BPMaterials[ mtidx ] ,
					-rayDir , normal , lightDir );
		} else {
			bc = PBR_Shade( PBRMaterials[ mtidx ] ,
					-rayDir , normal , lightDir );
		}

		if ( glowidx >= 0 ) {
			bc += Glow[ glowidx ];
		}
	}

	o_Color = bc;
	o_Z = r.x;
}