XtreemNodes/data/shader/MeshF.shader

159 lines
4.2 KiB
GLSL

#version 330 core
in vec3 Normal;
in vec2 TexCoords;
in vec3 FragPosition;
out vec4 FragColor;
#define PI 3.14159265359
#define MAX_LIGHTS 128
struct Material {
float Ao;
vec3 Albedo;
float Metallic;
float Roughness;
};
struct PointLight {
vec3 Color;
vec3 Position;
float Intensity;
};
struct DirectLight {
vec3 Color;
vec3 Position;
vec3 Direction;
float Intensity;
};
struct SpotLight {
vec3 Color;
vec3 Position;
vec3 Direction;
float ICutOff;
float OCutOff;
float Intensity;
};
// uniforms
uniform sampler2D AoMap;
uniform sampler2D AlbedoMap;
uniform sampler2D NormalMap;
uniform sampler2D MetallicMap;
uniform sampler2D RoughnessMap;
uniform vec3 CameraPos;
uniform Material material;
uniform int spotLightCount;
uniform SpotLight spotLights[MAX_LIGHTS];
uniform int pointLightCount;
uniform PointLight pointLights[MAX_LIGHTS];
uniform int directLightCount;
uniform DirectLight directLights[MAX_LIGHTS];
float DistributionGGX(vec3 N, vec3 H, float roughness) {
float a = roughness * roughness;
float a2 = a * a;
float NdotH = max(dot(N, H), 0.0);
float NdotH2 = NdotH * NdotH;
float nom = a2;
float denom = (NdotH2 * (a2 - 1.0) + 1.0);
denom = PI * denom * denom;
return nom / max(denom, 0.001); // prevent divide by zero for roughness=0.0 and NdotH=1.0
}
float GeometrySchlickGGX(float NdotV, float roughness) {
float r = (roughness + 1.0);
float k = (r * r) / 8.0;
float nom = NdotV;
float denom = NdotV * (1.0 - k) + k;
return nom / denom;
}
float GeometrySmith(vec3 N, vec3 V, vec3 L, float roughness) {
float NdotV = max(dot(N, V), 0.0);
float NdotL = max(dot(N, L), 0.0);
float ggx2 = GeometrySchlickGGX(NdotV, roughness);
float ggx1 = GeometrySchlickGGX(NdotL, roughness);
return ggx1 * ggx2;
}
vec3 fresnelSchlick(float cosTheta, vec3 F0) {
return F0 + (1.0 - F0) * pow(1.0 - cosTheta, 5.0);
}
vec3 ProcessLight(vec3 N, vec3 V, vec3 Ld, vec3 color, vec3 F0, float I, float roughness, float metallic, vec3 albedo) {
vec3 L = normalize(Ld);
vec3 H = normalize(V + L);
float distance = length(Ld);
float attenuation = I / (distance * distance);
vec3 radiance = color * attenuation;
// Cook-Torrance BRDF
float NDF = DistributionGGX(N, H, roughness);
float G = GeometrySmith(N, V, L, roughness);
vec3 F = fresnelSchlick(clamp(dot(H, V), 0.0, 1.0), F0);
vec3 nominator = NDF * G * F;
float denominator = 4 * max(dot(N, V), 0.0) * max(dot(N, L), 0.0);
vec3 specular = nominator / max(denominator, 0.001);
vec3 KS = F;
vec3 KD = vec3(1.0) - KS;
KD *= 1.0 - metallic;
float NdotL = max(dot(N, L), 0.0);
vec3 Lo = (KD * albedo / PI + specular) * radiance * NdotL;
return Lo;
}
void main() {
vec3 N = normalize(Normal);
vec3 V = normalize(CameraPos - FragPosition);
float ao = material.Ao + texture(AoMap, TexCoords).r;
vec3 albedo = pow(material.Albedo, vec3(2.2)) + pow(vec3(texture(AlbedoMap, TexCoords)), vec3(5.2));
float metallic = material.Metallic + texture(MetallicMap, TexCoords).r;
float roughness = material.Roughness + texture(RoughnessMap, TexCoords).r;
vec3 F0 = vec3(0.04);
F0 = mix(F0, albedo, metallic);
vec3 Luminance = vec3(0.0);
// Point lights
int count = (pointLightCount > MAX_LIGHTS) ? MAX_LIGHTS : pointLightCount;
for (int i = 0; i < count; i++) {
PointLight light = pointLights[i];
vec3 L = (light.Position - FragPosition);
Luminance += ProcessLight(N, V, L, light.Color, F0, light.Intensity, roughness, metallic, albedo);
}
// Directional lights
count = (directLightCount > MAX_LIGHTS) ? MAX_LIGHTS : directLightCount;
for (int i = 0; i < count; i++) {
DirectLight light = directLights[i];
Luminance += ProcessLight(N, V, light.Direction, light.Color, F0, light.Intensity, roughness, metallic, albedo);
}
// ambient
vec3 ambient = vec3(0.1f) * albedo * ao;
vec3 color = ambient + Luminance;
// HDR correction
color = color / (color + vec3(1.0));
// Gamma correction
color = pow(color, vec3(1.0 / 3.0));
FragColor = vec4(color, 1.0);
}