Some refactoring of light calculations in shaders

[libs/gl.git] / shaderlib / common.glsl

diff --git a/shaderlib/common.glsl b/shaderlib/common.glsl
index 94237c7acfd3cec3626497c85761db24b00e9106..4d6112d9f2b37a58127f6a5330837b5b55973217 100644 (file)
--- a/shaderlib/common.glsl
+++ b/shaderlib/common.glsl
@@ -8,6 +8,7 @@ uniform EnvMap
 
 uniform sampler2D normal_map;
 uniform samplerCube environment_map;
+uniform samplerCube irradiance_map;
 
 layout(constant_id=auto) const bool use_normal_map = false;
 
@@ -37,7 +38,7 @@ void standard_transform()
        mat4 vertex_tf = get_vertex_transform();
        mat3 normal_tf = get_normal_transform();
 
-       vec4 world_vertex = vertex_tf*get_vertex_position();
+       out vec4 world_vertex = vertex_tf*get_vertex_position();
        vec4 eye_vertex = eye_world_matrix*world_vertex;
        gl_Position = clip_eye_matrix*eye_vertex;
 
@@ -49,10 +50,6 @@ void standard_transform()
        vec3 eye_pos = (inverse(eye_world_matrix)*vec4(0.0, 0.0, 0.0, 1.0)).xyz;
        out vec3 world_look_dir = normalize(world_vertex.xyz-eye_pos);
 
-       out vec3 world_light_dir = light_sources[0].position.xyz-world_vertex.xyz*light_sources[0].position.w;
-
-       out vec3 world_halfway_dir = normalize(world_light_dir-world_look_dir);
-
        out float fog_coord = eye_vertex.z;
 
        if(use_clipping)
@@ -60,8 +57,6 @@ void standard_transform()
                for(int i=0; i<max_clip_planes; ++i)
                        gl_ClipDistance[i] = dot(world_vertex, clip_planes[i].equation);
        }
-
-       shadow_transform(world_vertex);
 }
 
 virtual void custom_transform()
@@ -76,6 +71,12 @@ void main()
 }
 
 #pragma MSP stage(fragment)
+struct IncomingLight
+{
+       vec3 direction;
+       vec3 color;
+};
+
 virtual vec3 get_fragment_normal()
 {
        if(use_normal_map)
@@ -84,15 +85,29 @@ virtual vec3 get_fragment_normal()
                return normalize(world_normal);
 }
 
-virtual vec3 get_environment_sample(vec3 direction)
+virtual IncomingLight get_incoming_light(int index, vec3 world_pos)
 {
-       return texture(environment_map, env_world_matrix*direction).rgb;
+       vec4 light_pos = light_sources[index].position;
+       vec3 rel_pos = light_pos.xyz-world_pos*light_pos.w;
+       float d = length(rel_pos);
+       return IncomingLight(rel_pos/d, light_sources[index].color);
+}
+
+virtual vec3 get_environment_sample(vec3 direction, float roughness)
+{
+       float lod = (2-roughness)*roughness*(textureQueryLevels(environment_map)-1);
+       return textureLod(environment_map, env_world_matrix*direction, lod).rgb;
 }
 
 virtual vec3 get_reflection(vec3 normal, vec3 look)
 {
        vec3 reflect_dir = reflect(look, normal);
-       return get_environment_sample(reflect_dir);
+       return get_environment_sample(reflect_dir, 0.0);
+}
+
+virtual vec3 get_irradiance_sample(vec3 normal)
+{
+       return texture(irradiance_map, env_world_matrix*normal).rgb;
 }
 
 vec3 apply_fog(vec3 color)