X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=shaderlib%2Fcooktorrance.glsl;h=f8aed8267273fcb4f1ac97c929e3823ba29dbcb0;hb=e05c77d2e3582a6962f42dcec0fc5f7845ff448d;hp=6a7ebb387fdf3e39aa772940b22b9a5b02007da9;hpb=96c0341d421136d57f4d1a1405e1f61e10656821;p=libs%2Fgl.git

diff --git a/shaderlib/cooktorrance.glsl b/shaderlib/cooktorrance.glsl
index 6a7ebb38..f8aed826 100644
--- a/shaderlib/cooktorrance.glsl
+++ b/shaderlib/cooktorrance.glsl
@@ -2,17 +2,37 @@ import msp_interface;
 import common;
 import shadow;
 
-const bool use_base_color_map = false;
-const bool use_metalness_map = false;
-const bool use_roughness_map = false;
-const bool use_occlusion_map = false;
-const bool use_emission = false;
-const bool use_emission_map = false;
+struct PbrMaterialParameters
+{
+	vec4 base_color;
+	vec4 emission;
+	float metalness;
+	float roughness;
+};
+
+uniform PbrMaterial
+{
+	PbrMaterialParameters pbr_material;
+};
+
+uniform sampler2D base_color_map;
+uniform sampler2D metalness_map;
+uniform sampler2D roughness_map;
+uniform sampler2D occlusion_map;
+uniform sampler2D emission_map;
+uniform sampler2D fresnel_lookup;
+
+layout(constant_id=auto) const bool use_base_color_map = false;
+layout(constant_id=auto) const bool use_metalness_map = false;
+layout(constant_id=auto) const bool use_roughness_map = false;
+layout(constant_id=auto) const bool use_occlusion_map = false;
+layout(constant_id=auto) const bool use_emission = false;
+layout(constant_id=auto) const bool use_emission_map = false;
 
 const float PI = 3.1415926535;
 
 #pragma MSP stage(fragment)
-vec4 get_base_color()
+virtual vec4 get_base_color()
 {
 	if(use_base_color_map)
 		return texture(base_color_map, texcoord.xy);
@@ -20,7 +40,7 @@ vec4 get_base_color()
 		return pbr_material.base_color;
 }
 
-float get_metalness_value()
+virtual float get_metalness_value()
 {
 	if(use_metalness_map)
 		return texture(metalness_map, texcoord.xy).r;
@@ -28,7 +48,7 @@ float get_metalness_value()
 		return pbr_material.metalness;
 }
 
-float get_roughness_value()
+virtual float get_roughness_value()
 {
 	if(use_roughness_map)
 		return texture(roughness_map, texcoord.xy).r;
@@ -36,7 +56,7 @@ float get_roughness_value()
 		return pbr_material.roughness;
 }
 
-float get_occlusion_value()
+virtual float get_occlusion_value()
 {
 	if(use_occlusion_map)
 		return texture(occlusion_map, texcoord.xy).r;
@@ -44,7 +64,7 @@ float get_occlusion_value()
 		return 1.0;
 }
 
-vec3 get_emission_color()
+virtual vec3 get_emission_color()
 {
 	if(use_emission_map)
 		return texture(emission_map, texcoord.xy).rgb;
@@ -67,7 +87,8 @@ float normal_distribution_ggxtr(vec3 normal, vec3 halfway, float roughness)
 	float rough_q = roughness * roughness;
 	rough_q *= rough_q;
 	float denom = n_dot_h*n_dot_h*(rough_q-1)+1;
-	// Scale by pi to get a result per steradian, suitable for integration
+	/* Scale by pi to normalize the total area of the microfacets as projected
+	to the macrosurface */
 	return rough_q/(PI*denom*denom);
 }
 
@@ -94,7 +115,7 @@ vec3 fresnel_schlick(vec3 halfway, vec3 look, vec3 base_color, float metalness)
 {
 	// 0.04 is a decent approximation for dielectric base reflectivity
 	vec3 f0 = mix(vec3(0.04), base_color, metalness);
-	return mix(f0, vec3(1.0), pow(1.0-dot(halfway, look), 5.0));
+	return mix(f0, vec3(1.0), pow(max(1.0-dot(halfway, look), 0.0), 5.0));
 }
 
 /* Computes the full contribution of a single light */
@@ -107,20 +128,28 @@ vec3 cooktorrance_one_light_direct(vec3 normal, vec3 look, vec3 light, vec3 ligh
 	vec3 k_spec = fresnel_schlick(halfway, light, base_color, metalness);
 	vec3 k_diff = (1.0-k_spec)*(1.0-metalness);
 
-	float denom = max(4.0*max(dot(normal, -look), 0.0)*max(dot(normal, light), 0.0), 0.001);
-	return max(dot(normal, light), 0.0)*light_color*(k_diff*lambert_diffuse(base_color)+k_spec*ndist*geom/denom);
+	float spec_denom = max(4.0*max(dot(normal, -look), 0.0)*max(dot(normal, light), 0.0), 0.001);
+	return max(dot(normal, light), 0.0)*light_color*(k_diff*lambert_diffuse(base_color)+k_spec*ndist*geom/spec_denom);
+}
+
+vec3 cooktorrance_environment(vec3 normal, vec3 look, vec3 base_color, float metalness, float roughness)
+{
+	vec3 f0 = mix(vec3(0.04), base_color, metalness);
+	vec2 scale_bias = texture(fresnel_lookup, vec2(roughness, max(dot(normal, -look), 0.0))).rg;
+	vec3 k_spec = f0*scale_bias.x+scale_bias.y;
+	vec3 k_diff = (1.0-k_spec)*(1.0-metalness);
+
+	return (k_diff*base_color+k_spec)*ambient_color.rgb;
 }
 
 vec3 cooktorrance_lighting(vec3 normal, vec3 look, vec3 base_color, float metalness, float roughness)
 {
-	vec3 light;
-	if(use_normal_map)
-		light = normalize(tbn_light_dir);
-	else
-		light = normalize(eye_light_dir);
+	vec3 light = normalize(world_light_dir);
 
 	float shadow = get_shadow_factor(0);
-	vec3 color = cooktorrance_one_light_direct(normal, look, light, light_sources[0].diffuse.rgb, base_color, metalness, roughness)*shadow;
+	vec3 color = cooktorrance_one_light_direct(normal, look, light, light_sources[0].color, base_color, metalness, roughness)*shadow;
+
+	color += cooktorrance_environment(normal, look, base_color, metalness, roughness);
 
 	color *= get_occlusion_value();
 
@@ -132,18 +161,8 @@ vec3 cooktorrance_lighting(vec3 normal, vec3 look, vec3 base_color, float metaln
 
 void main()
 {
-	vec3 normal;
-	vec3 look;
-	if(use_normal_map)
-	{
-		normal = get_fragment_normal();
-		look = normalize(tbn_look_dir);
-	}
-	else
-	{
-		normal = normalize(eye_normal);
-		look = normalize(eye_look_dir);
-	}
+	vec3 normal = get_fragment_normal();
+	vec3 look = normalize(world_look_dir);
 
 	vec4 base_color = get_base_color();
 	float metalness = get_metalness_value();