PlanetEditor/grk/planet-editor/shaders/shader_pbr.frag

239 lines
5.9 KiB
GLSL

#version 430 core
layout (location = 0) out vec4 outColor;
layout (location = 1) out vec4 BrightColor;
float AMBIENT = 0.05;
float PI = 3.14159;
uniform sampler2D colorTexture;
uniform sampler2D textureNormal;
uniform float exposition;
uniform float metallic;
uniform float roughness;
uniform vec3 cameraPos;
uniform vec3 sunDir;
uniform vec3 sunColor;
uniform vec3 lightPos;
uniform vec3 lightColor;
uniform bool atmosphereCheck;
uniform bool toneMappingCheck;
uniform float time;
uniform float cloudIntensity;
uniform float cloudMotion;
uniform float cloudBrightness;
in vec3 vecNormal;
in vec3 worldPos;
in vec2 vtc;
in vec3 viewDirTS;
in vec3 lightDirTS;
in vec3 sunDirTS;
float DistributionGGX(vec3 normal, vec3 H, float roughness)
{
float a = roughness * roughness;
float a2 = a * a;
float NdotH = max(dot(normal, H), 0.0);
float NdotH2 = NdotH * NdotH;
float num = a2;
float denom = (NdotH2 * (a2 - 1.0) + 1.0);
denom = PI * denom * denom;
return num / denom;
}
float GeometrySchlickGGX(float NdotV, float roughness)
{
float r = (roughness + 1.0);
float k = (r * r) / 8.0;
float num = NdotV;
float denom = NdotV * (1.0 - k) + k;
return num / denom;
}
float GeometrySmith(vec3 normal, vec3 V, vec3 lightDir, float roughness)
{
float NdotV = max(dot(normal, V), 0.0);
float NdotL = max(dot(normal, lightDir), 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(clamp(1.0 - cosTheta, 0.0, 1.0), 5.0);
}
vec3 PBRLight(vec3 lightDir, vec3 radiance, vec3 normal, vec3 V, vec3 color)
{
float diffuse = max(0, dot(normal, lightDir));
vec3 F0 = vec3(0.04);
F0 = mix(F0, color, metallic);
vec3 H = normalize(V + lightDir);
// cook-torrance brdf
float NDF = DistributionGGX(normal, H, roughness);
float G = GeometrySmith(normal, V, lightDir, roughness);
vec3 F = fresnelSchlick(max(dot(H, V), 0.0), F0);
vec3 kS = F;
vec3 kD = vec3(1.0) - kS;
kD *= 1.0 - metallic;
vec3 numerator = NDF * G * F;
float denominator = 4.0 * max(dot(normal, V), 0.0) * max(dot(normal, lightDir), 0.0) + 0.0001;
vec3 specular = numerator / denominator;
// add to outgoing radiance Lo
float NdotL = max(dot(normal, lightDir), 0.0);
return (kD * color / PI + specular) * radiance * NdotL;
}
vec3 toneMapping(vec3 color)
{
float exposure = 0.06;
vec3 mapped = 1 - exp(-color * exposure);
return mapped;
}
float random (in vec2 st)
{
return fract(sin(dot(st.xy,
vec2(32.9898,128.233)))*
43758.5453123);
}
float noise (in vec2 st)
{
vec2 i = floor(st);
vec2 f = fract(st);
float a = random(i);
float b = random(i + vec2(1.0, 0.0));
float c = random(i + vec2(0.0, 1.0));
float d = random(i + vec2(1.0, 1.0));
vec2 u = f * f * (3.0 - 2.0 * f);
return mix(a, b, u.x) +
(c - a)* u.y * (1.0 - u.x) +
(d - b) * u.x * u.y;
}
#define OCTAVES 6
float fbm (in vec2 st)
{
// Initial values
float value = 0.0;
float amplitude = .5;
float frequency = 0.;
// Loop of octaves
for (int i = 0; i < OCTAVES; i++) {
value += amplitude * noise(st);
st *= 2.;
amplitude *= .5;
}
return value;
}
vec3 noiseColor()
{
vec2 st = vtc.xy;
vec2 mirroredSt = vec2(1.0 - st.x, st.y);
float timeOffset = time * cloudMotion;
st.x -= timeOffset;
mirroredSt.x += timeOffset; // Inverse direction for mirrored effect
st.x = fract(st.x);
mirroredSt.x = fract(mirroredSt.x);
vec3 color = vec3(fbm(st * cloudIntensity));
vec3 mirroredColor = vec3(fbm(mirroredSt * cloudIntensity));
float blend = smoothstep(0.45, 0.55, st.x);
vec3 noiseColor = mix(color, mirroredColor, blend);
return noiseColor;
}
void main()
{
vec3 normal = normalize(vecNormal);
vec3 viewDir = normalize(cameraPos - worldPos);
vec3 lightDir = normalize(lightPos - worldPos);
vec3 textureColor = texture2D(colorTexture, vtc).rgb;
vec3 N = texture2D(textureNormal, vtc).rgb;
vec3 normalTexture = normalize((N * 2.0 - 1.0));
float diffuseNormal = max(0, dot(normalTexture, lightDir));
if (atmosphereCheck)
{
float atmosphereDot = dot(normal, viewDir);
vec3 atmosphereColor = vec3(0.0, 0.44, 1.0);
textureColor = mix(textureColor, atmosphereColor, pow(1 - atmosphereDot, 3));
}
vec3 diffuseColor = textureColor * min(1, AMBIENT + diffuseNormal);
vec3 toneMappedColor;
if (toneMappingCheck)
{
vec3 distance = lightColor / pow(length(lightPos - worldPos), 2.0) * 10;
toneMappedColor = toneMapping(diffuseColor * distance);
//gamma correction
toneMappedColor = pow(toneMappedColor, vec3(1.0/2.2));
}
else
toneMappedColor = textureColor;
vec3 ambient = AMBIENT * toneMappedColor;
vec3 attenuatedLightColor = lightColor / pow(length(lightPos - worldPos), 2);
vec3 illumination = ambient + PBRLight(lightDir, attenuatedLightColor, normal, viewDir, toneMappedColor);
//sun
illumination = illumination + PBRLight(sunDir, sunColor, normal, viewDir, toneMappedColor);
vec3 pbrColor = vec3(1.0) - exp(-illumination * exposition);
vec3 finalColor;
if (atmosphereCheck)
{
vec3 noiseColor = noiseColor() * min(1, 20.0 * max(0.02, dot(normal, lightDir))) * lightColor * cloudBrightness;
finalColor = mix(pbrColor, noiseColor, noiseColor.r);
}
else
finalColor = pbrColor;
float brightness = dot(finalColor, vec3(0.2126, 0.7152, 0.0722));
if(brightness > 0.2)
BrightColor = vec4(finalColor, 1.0);
else
BrightColor = vec4(0.0, 0.0, 0.0, 1.0);
outColor = vec4(finalColor, 1.0);
}