//======= Copyright (c) 2015-2020 Vera Visions LLC. All rights reserved. =======
//
// Purpose: 
//
// Alternative way of blending/masking terrain between to diffuse textures.
//==============================================================================

!!ver 110
!!permu FOG
!!permu BUMP
!!permu DELUXE
!!samps diffuse normalmap

!!samps lightmap
!!samps =LIGHTSTYLED lightmap1 lightmap2 lightmap3
!!samps =DELUXE deluxemap
!!samps =LIGHTSTYLED =DELUXE deluxemap1 deluxemap2 deluxemap3

!!permu FAKESHADOWS
!!cvardf r_glsl_pcf
!!samps =FAKESHADOWS shadowmap

!!cvardf dev_skipnormal

#include "sys/defs.h"

varying vec2 tex_c;
varying vec4 vex_color;

varying vec2 lm0;
#ifdef LIGHTSTYLED
varying vec2 lm1, lm2, lm3;
#endif

#ifdef FAKESHADOWS
	varying vec4 vtexprojcoord;
#endif

#ifdef VERTEX_SHADER
	void lightmapped_init(void)
	{
		lm0 = v_lmcoord;
		#ifdef LIGHTSTYLED
		lm1 = v_lmcoord2;
		lm2 = v_lmcoord3;
		lm3 = v_lmcoord4;
		#endif
	}

	void main ( void )
	{
		lightmapped_init();
		tex_c = v_texcoord;
		vex_color = v_colour;

		gl_Position = ftetransform();
		
		#ifdef FAKESHADOWS
		vtexprojcoord = (l_cubematrix*vec4(v_position.xyz, 1.0));
		#endif
	}
#endif

#ifdef FRAGMENT_SHADER
	#include "sys/fog.h"
	#include "sys/pcf.h"

	vec3 lightmap_fragment (vec3 normal_f)
	{
		vec3 lightmaps;

#ifdef LIGHTSTYLED
		lightmaps  = texture2D(s_lightmap0, lm0).rgb * e_lmscale[0].rgb * dot(normal_f, (texture2D(s_deluxemap0, lm0).rgb - 0.5) * 2.0);
		lightmaps += texture2D(s_lightmap1, lm1).rgb * e_lmscale[1].rgb * dot(normal_f, (texture2D(s_deluxemap1, lm1).rgb - 0.5) * 2.0);
		lightmaps += texture2D(s_lightmap2, lm2).rgb * e_lmscale[2].rgb * dot(normal_f, (texture2D(s_deluxemap2, lm2).rgb - 0.5) * 2.0);
		lightmaps += texture2D(s_lightmap3, lm3).rgb * e_lmscale[3].rgb * dot(normal_f, (texture2D(s_deluxemap3, lm3).rgb - 0.5) * 2.0);
#else
		lightmaps  = texture2D(s_lightmap, lm0).rgb * e_lmscale.rgb * dot(normal_f, (texture2D(s_deluxemap, lm0).rgb - 0.5) * 2.0);
#endif
		return lightmaps;
	}

	void main ( void )
	{
		vec3 diffuse_f = texture2D( s_diffuse, tex_c ).rgb;
		vec3 normal_f = normalize(texture2D(s_normalmap, tex_c).rgb - 0.5);
		float bw = (diffuse_f.r + diffuse_f.g + diffuse_f.b) / 3.0;
		vec4 vcol = vex_color;
		float alpha = 1.0;

		if (vcol.a < 1.0) {
			if (bw > vcol.a) {
				discard;
			}
		}
		
		if (bw > (vcol.a * 0.25))
			alpha = vcol.a;

		diffuse_f *= lightmap_fragment(normal_f);

		#ifdef FAKESHADOWS
		diffuse_f *= ShadowmapFilter(s_shadowmap, vtexprojcoord);
		#endif

		gl_FragColor = fog4( vec4(diffuse_f, alpha) );
	}
#endif