1
0
Fork 0
fgdata/Shaders/HDR/lighting.frag
2021-09-01 04:26:03 +02:00

119 lines
3.3 KiB
GLSL

#version 330 core
out vec3 fragColor;
in vec2 texCoord;
uniform sampler2D gbuffer0_tex;
uniform sampler2D gbuffer1_tex;
uniform sampler2D gbuffer2_tex;
uniform sampler2D depth_tex;
uniform sampler2D ao_tex;
uniform bool ambient_occlusion_enabled;
uniform bool debug_shadow_cascades;
uniform mat4 fg_ViewMatrixInverse;
uniform mat4 fg_ProjectionMatrix;
uniform vec3 fg_SunDirection;
vec3 decodeNormal(vec2 f);
vec3 positionFromDepth(vec2 pos, float depth);
float getShadowing(vec3 p, vec3 n, vec3 l, mat4 viewToClip);
vec3 debugShadowColor(vec3 p, vec3 n, vec3 l);
vec3 getF0Reflectance(vec3 baseColor, float metallic);
vec3 evaluateLight(
vec3 baseColor,
float metallic,
float roughness,
vec3 f0,
vec3 intensity,
float visibility,
vec3 n,
vec3 l,
vec3 v,
float NdotL,
float NdotV);
vec3 evaluateIBL(
vec3 baseColor,
float metallic,
float roughness,
vec3 f0,
float visibility,
vec3 nWorldSpace,
float NdotV,
vec3 reflected);
vec3 addAerialPerspective(vec3 color, vec2 coord, float depth);
vec3 getSunIntensity();
float GTAOMultiBounce(float x, vec3 albedo)
{
// Use luminance instead of albedo because colored multibounce looks bad
// Idea borrowed from Blender Eevee
float lum = dot(albedo, vec3(0.333));
float a = 2.0404 * lum - 0.3324;
float b = -4.7951 * lum + 0.6417;
float c = 2.7552 * lum + 0.6903;
return max(x, ((x * a + b) * x + c) * x);
}
void main()
{
vec4 gbuffer0 = texture(gbuffer0_tex, texCoord);
vec4 gbuffer1 = texture(gbuffer1_tex, texCoord);
vec4 gbuffer2 = texture(gbuffer2_tex, texCoord);
float depth = texture(depth_tex, texCoord).r;
// Unpack G-Buffer
vec3 n = decodeNormal(gbuffer0.rg);
float roughness = gbuffer0.b;
uint matId = uint(gbuffer0.a * 4.0);
vec3 baseColor = gbuffer1.rgb;
float metallic = gbuffer1.a;
float occlusion = gbuffer2.a;
vec3 pos = positionFromDepth(texCoord, depth);
vec3 v = normalize(-pos);
vec3 l = fg_SunDirection;
float NdotL = dot(n, l);
float NdotV = clamp(abs(dot(n, v)), 0.001, 1.0);
vec3 f0 = getF0Reflectance(baseColor, metallic);
vec3 sunIlluminance = getSunIntensity() * clamp(NdotL, 0.0, 1.0);
float shadowFactor = getShadowing(pos, n, l, fg_ProjectionMatrix);
vec3 color = evaluateLight(baseColor,
metallic,
roughness,
f0,
sunIlluminance,
shadowFactor,
n, l, v,
NdotL, NdotV);
float ao = occlusion;
if (ambient_occlusion_enabled) {
ao *= GTAOMultiBounce(texture(ao_tex, texCoord).r, baseColor);
}
vec3 worldNormal = (fg_ViewMatrixInverse * vec4(n, 0.0)).xyz;
vec3 worldReflected = (fg_ViewMatrixInverse * vec4(reflect(-v, n), 0.0)).xyz;
color += evaluateIBL(baseColor,
metallic,
roughness,
f0,
ao,
worldNormal,
NdotV,
worldNormal);
color = addAerialPerspective(color, texCoord, length(pos));
if (debug_shadow_cascades)
color *= debugShadowColor(pos, n, l);
fragColor = color;
}