armory/Shaders/volumetric_light/volumetric_light.frag.glsl
N8n5h 5509096158 fix volumetric lights not working with shadow map atlas enabled
Added missing code so the shader refers to the correct variable when
using shadow map atlasing.
2021-08-06 18:34:39 -03:00

167 lines
4 KiB
GLSL

// http://sebastien.hillaire.free.fr/index.php?option=com_content&view=article&id=72&Itemid=106
#version 450
#include "compiled.inc"
#include "std/gbuffer.glsl"
#include "std/shadows.glsl"
#ifdef _Clusters
#include "std/clusters.glsl"
#endif
uniform sampler2D gbufferD;
uniform sampler2D snoise;
#ifdef _Clusters
uniform vec4 lightsArray[maxLights * 3];
#ifdef _Spot
uniform vec4 lightsArraySpot[maxLights];
#endif
uniform sampler2D clustersData;
uniform vec2 cameraPlane;
#endif
#ifdef _ShadowMap
#ifdef _SinglePoint
#ifdef _Spot
uniform sampler2DShadow shadowMapSpot[1];
uniform mat4 LWVPSpot[1];
#else
uniform samplerCubeShadow shadowMapPoint[1];
uniform vec2 lightProj;
#endif
#endif
#ifdef _Clusters
uniform samplerCubeShadow shadowMapPoint[4];
uniform vec2 lightProj;
#ifdef _Spot
uniform sampler2DShadow shadowMapSpot[4];
uniform mat4 LWVPSpot[maxLightsCluster];
#endif
#endif
#endif
#ifdef _Sun
uniform vec3 sunDir;
uniform vec3 sunCol;
#ifdef _ShadowMap
#ifdef _ShadowMapAtlas
#ifndef _SingleAtlas
uniform sampler2DShadow shadowMapAtlasSun;
#else
uniform sampler2DShadow shadowMapAtlas;
#endif
#else
uniform sampler2DShadow shadowMap;
#endif
uniform float shadowsBias;
#ifdef _CSM
//!uniform vec4 casData[shadowmapCascades * 4 + 4];
#else
uniform mat4 LWVP;
#endif
#endif // _ShadowMap
#endif
#ifdef _SinglePoint // Fast path for single light
uniform vec3 pointPos;
uniform vec3 pointCol;
#ifdef _ShadowMap
uniform float pointBias;
#endif
#ifdef _Spot
uniform vec3 spotDir;
uniform vec2 spotData;
#endif
#endif
uniform vec2 cameraProj;
uniform vec3 eye;
uniform vec3 eyeLook;
in vec2 texCoord;
in vec3 viewRay;
out float fragColor;
const float tScat = 0.08;
const float tAbs = 0.0;
const float tExt = tScat + tAbs;
const float stepLen = 1.0 / volumSteps;
const float lighting = 0.4;
void rayStep(inout vec3 curPos, inout float curOpticalDepth, inout float scatteredLightAmount, float stepLenWorld, vec3 viewVecNorm) {
curPos += stepLenWorld * viewVecNorm;
const float density = 1.0;
float l1 = lighting * stepLenWorld * tScat * density;
curOpticalDepth *= exp(-tExt * stepLenWorld * density);
float visibility = 0.0;
#ifdef _Sun
#ifdef _CSM
mat4 LWVP = mat4(casData[4], casData[4 + 1], casData[4 + 2], casData[4 + 3]);
#endif
vec4 lPos = LWVP * vec4(curPos, 1.0);
lPos.xyz /= lPos.w;
visibility = texture(
#ifdef _ShadowMapAtlas
#ifndef _SingleAtlas
shadowMapAtlasSun
#else
shadowMapAtlas
#endif
#else
shadowMap
#endif
, vec3(lPos.xy, lPos.z - shadowsBias));
#endif
#ifdef _SinglePoint
#ifdef _Spot
vec4 lPos = LWVPSpot[0] * vec4(curPos, 1.0);
visibility = shadowTest(shadowMapSpot[0], lPos.xyz / lPos.w, pointBias);
float spotEffect = dot(spotDir, normalize(pointPos - curPos)); // lightDir
if (spotEffect < spotData.x) { // x - cutoff, y - cutoff - exponent
visibility *= smoothstep(spotData.y, spotData.x, spotEffect);
}
#else
vec3 ld = pointPos - curPos;
visibility = PCFCube(shadowMapPoint[0], ld, -normalize(ld), pointBias, lightProj, vec3(0.0));
#endif
#endif
#ifdef _Clusters
#endif
scatteredLightAmount += curOpticalDepth * l1 * visibility;
}
void main() {
float pixelRayMarchNoise = textureLod(snoise, texCoord * 100, 0.0).r * 2.0 - 1.0;
float depth = textureLod(gbufferD, texCoord, 0.0).r * 2.0 - 1.0;
vec3 p = getPos(eye, eyeLook, normalize(viewRay), depth, cameraProj);
vec3 viewVec = p - eye;
float worldPosDist = length(viewVec);
vec3 viewVecNorm = viewVec / worldPosDist;
float startDepth = 0.1;
startDepth = min(worldPosDist, startDepth);
float endDepth = 20.0;
endDepth = min(worldPosDist, endDepth);
vec3 curPos = eye + viewVecNorm * startDepth;
float stepLenWorld = stepLen * (endDepth - startDepth);
float curOpticalDepth = exp(-tExt * stepLenWorld);
float scatteredLightAmount = 0.0;
curPos += stepLenWorld * viewVecNorm * pixelRayMarchNoise;
for (float l = stepLen; l < 0.99999; l += stepLen) { // Do not do the first and last steps
rayStep(curPos, curOpticalDepth, scatteredLightAmount, stepLenWorld, viewVecNorm);
}
fragColor = scatteredLightAmount * volumAirTurbidity;
}