diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gles3/shaders/scene.glsl | 60 |
1 files changed, 55 insertions, 5 deletions
diff --git a/drivers/gles3/shaders/scene.glsl b/drivers/gles3/shaders/scene.glsl index df1645db1f..86aac2801a 100644 --- a/drivers/gles3/shaders/scene.glsl +++ b/drivers/gles3/shaders/scene.glsl @@ -165,18 +165,68 @@ uniform int spot_light_count; out vec4 diffuse_light_interp; out vec4 specular_light_interp; + void light_compute(vec3 N, vec3 L, vec3 V, vec3 light_color, float roughness, inout vec3 diffuse, inout vec3 specular) { - float dotNL = max(dot(N, L), 0.0); - diffuse += dotNL * light_color / M_PI; + + float NdotL = dot(N, L); + float cNdotL = max(NdotL, 0.0); // clamped NdotL + float NdotV = dot(N, V); + float cNdotV = max(NdotV, 0.0); + +#if defined(DIFFUSE_OREN_NAYAR) + vec3 diffuse_brdf_NL; +#else + float diffuse_brdf_NL; // BRDF times N.L for calculating diffuse radiance +#endif + +#if defined(DIFFUSE_LAMBERT_WRAP) + // energy conserving lambert wrap shader + diffuse_brdf_NL = max(0.0, (NdotL + roughness) / ((1.0 + roughness) * (1.0 + roughness))); + +#elif defined(DIFFUSE_OREN_NAYAR) + + { + // see http://mimosa-pudica.net/improved-oren-nayar.html + float LdotV = dot(L, V); + + float s = LdotV - NdotL * NdotV; + float t = mix(1.0, max(NdotL, NdotV), step(0.0, s)); + + float sigma2 = roughness * roughness; // TODO: this needs checking + vec3 A = 1.0 + sigma2 * (-0.5 / (sigma2 + 0.33) + 0.17 * diffuse_color / (sigma2 + 0.13)); + float B = 0.45 * sigma2 / (sigma2 + 0.09); + + diffuse_brdf_NL = cNdotL * (A + vec3(B) * s / t) * (1.0 / M_PI); + } +#else + // lambert by default for everything else + diffuse_brdf_NL = cNdotL * (1.0 / M_PI); +#endif + + diffuse += light_color * diffuse_brdf_NL; if (roughness > 0.0) { + // D + float specular_brdf_NL = 0.0; + +#if !defined(SPECULAR_DISABLED) + //normalized blinn always unless disabled vec3 H = normalize(V + L); - float dotNH = max(dot(N, H), 0.0); - float intensity = (roughness >= 1.0 ? 1.0 : pow(dotNH, (1.0 - roughness) * 256.0)); - specular += light_color * intensity; + float cNdotH = max(dot(N, H), 0.0); + float cVdotH = max(dot(V, H), 0.0); + float cLdotH = max(dot(L, H), 0.0); + float shininess = exp2(15.0 * (1.0 - roughness) + 1.0) * 0.25; + float blinn = pow(cNdotH, shininess); + blinn *= (shininess + 8.0) * (1.0 / (8.0 * M_PI)); + specular_brdf_NL = (blinn) / max(4.0 * cNdotV * cNdotL, 0.75); +#endif + + specular += specular_brdf_NL * light_color * (1.0 / M_PI); } + + } void light_process_omni(int idx, vec3 vertex, vec3 eye_vec, vec3 normal, float roughness, inout vec3 diffuse, inout vec3 specular) { |