@babylonjs/core/ShadersWGSL/iblShadowVoxelTracing.fragment.js

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// Do not edit.
import { ShaderStore } from "../Engines/shaderStore.js";
const name = "iblShadowVoxelTracingPixelShader";
const shader = `#define PI 3.1415927
varying vUV: vec2f;
#define DISABLE_UNIFORMITY_ANALYSIS
var depthSampler: texture_2d<f32>;var worldNormalSampler : texture_2d<f32>;var blueNoiseSampler: texture_2d<f32>;var icdfSamplerSampler: sampler;var icdfSampler: texture_2d<f32>;var voxelGridSamplerSampler: sampler;var voxelGridSampler: texture_3d<f32>;
#ifdef COLOR_SHADOWS
var iblSamplerSampler: sampler;var iblSampler: texture_cube<f32>;
#endif
uniform shadowParameters: vec4f;
#define SHADOWdirs uniforms.shadowParameters.x
#define SHADOWframe uniforms.shadowParameters.y
#define SHADOWenvRot uniforms.shadowParameters.w
uniform voxelBiasParameters : vec4f;
#define highestMipLevel uniforms.voxelBiasParameters.z
uniform sssParameters: vec4f;
#define SSSsamples uniforms.sssParameters.x
#define SSSstride uniforms.sssParameters.y
#define SSSmaxDistance uniforms.sssParameters.z
#define SSSthickness uniforms.sssParameters.w
uniform shadowOpacity: vec4f;uniform projMtx: mat4x4f;uniform viewMtx: mat4x4f;uniform invProjMtx: mat4x4f;uniform invViewMtx: mat4x4f;uniform wsNormalizationMtx: mat4x4f;uniform invVPMtx: mat4x4f;
#define PI 3.1415927
#define GOLD 0.618034
struct AABB3f {m_min: vec3f,
m_max: vec3f,};struct Ray {orig: vec3f,
dir: vec3f,
dir_rcp: vec3f,
t_min: f32,
t_max: f32,};fn make_ray(origin: vec3f,direction: vec3f,tmin: f32,
tmax: f32)->Ray {var ray: Ray;ray.orig=origin;ray.dir=direction;ray.dir_rcp=1.0f/direction;ray.t_min=tmin;ray.t_max=tmax;return ray;}
fn ray_box_intersection(aabb: AABB3f,ray: Ray ,
distance_near: ptr<function,f32>,distance_far: ptr<function,f32>)->bool{var tbot: vec3f=ray.dir_rcp*(aabb.m_min-ray.orig);var ttop: vec3f=ray.dir_rcp*(aabb.m_max-ray.orig);var tmin: vec3f=min(ttop,tbot);var tmax: vec3f=max(ttop,tbot);*distance_near=max(ray.t_min,max(tmin.x,max(tmin.y,tmin.z)));*distance_far=min(ray.t_max,min(tmax.x,min(tmax.y,tmax.z)));return *distance_near<=*distance_far;}
#if VOXEL_MARCH_DIAGNOSTIC_INFO_OPTION
struct VoxelMarchDiagnosticInfo {heat: f32,
voxel_intersect_coords: vec3i,};
#endif
fn hash(i: u32)->u32 {var temp=i ^ (i>>16u);temp*=0x7FEB352Du;temp ^= temp>>15u;temp*=0x846CA68Bu;temp ^= temp>>16u;return temp;}
fn uintBitsToFloat(x: u32)->f32 {return bitcast<f32>(x);}
fn uint2float(i: u32)->f32 {return uintBitsToFloat(0x3F800000u | (i>>9u))-1.0;}
fn uv_to_normal(uv: vec2f)->vec3f {var N: vec3f;var uvRange: vec2f=uv;var theta: f32=uvRange.x*2.0*PI;var phi: f32=uvRange.y*PI;N.x=cos(theta)*sin(phi);N.z=sin(theta)*sin(phi);N.y=cos(phi);return N;}
fn plasticSequence(rstate: u32)->vec2f {return vec2f(uint2float(rstate*3242174889u),
uint2float(rstate*2447445414u));}
fn goldenSequence(rstate: u32)->f32 {return uint2float(rstate*2654435769u);}
fn distanceSquared(a: vec2f,b: vec2f)->f32 {var diff: vec2f=a-b;return dot(diff,diff);}
fn genTB(N: vec3f,T: ptr<function,vec3f>,B: ptr<function,vec3f>) {var s: f32=select(1.0,-1.0,N.z<0.0);var a: f32=-1.0/(s+N.z);var b: f32=N.x*N.y*a;*T= vec3f(1.0+s*N.x*N.x*a,s*b,-s*N.x);*B= vec3f(b,s+N.y*N.y*a,-N.y);}
fn lessThan(x: vec3f,y: vec3f)->vec3<bool> {return x<y;}
#ifdef VOXEL_MARCH_DIAGNOSTIC_INFO_OPTION
fn anyHitVoxels(ray_vs: Ray,
voxel_march_diagnostic_info: ptr<function,VoxelMarchDiagnosticInfo>)->bool {
#else
fn anyHitVoxels(ray_vs: Ray)->bool {
#endif
var stack=array<i32,24>(); 
var invD: vec3f=ray_vs.dir_rcp;var D: vec3f=ray_vs.dir;var O: vec3f=ray_vs.orig;var negD=vec3i(lessThan(D, vec3f(0,0,0)));var voxel0: i32=negD.x | (negD.y<<1) | (negD.z<<2);var t0: vec3f=-O*invD;var t1=(vec3f(1.0)-O)*invD;var maxLod: i32= i32(highestMipLevel);var stackLevel: i32=0;
#if VOXEL_MARCH_DIAGNOSTIC_INFO_OPTION
var steps: u32=0u;
#endif
stack[stackLevel]=maxLod<<24;stackLevel++;while (stackLevel>0) {stackLevel=stackLevel-1;var elem: i32=stack[stackLevel];var Coords: vec4i =
vec4i(elem & 0xFF,(elem>>8) & 0xFF,(elem>>16) & 0xFF,elem>>24);if (Coords.w==0) {
#if VOXEL_MARCH_DIAGNOSTIC_INFO_OPTION
*voxel_march_diagnostic_info.heat= f32(steps)/24.0;
#endif
return true;}
#if VOXEL_MARCH_DIAGNOSTIC_INFO_OPTION
++steps;
#endif
var invRes: f32=exp2(f32(Coords.w-maxLod));var bbmin: vec3f=invRes*vec3f(Coords.xyz+negD);var bbmax: vec3f=invRes*vec3f(Coords.xyz-negD+vec3i(1));var mint: vec3f=mix(t0,t1,bbmin);var maxt: vec3f=mix(t0,t1,bbmax);var midt: vec3f=0.5*(mint+maxt);mint.x=max(0.0,mint.x);midt.x=max(0.0,midt.x);var nodeMask: u32= u32(
round(textureLoad(voxelGridSampler,Coords.xyz,Coords.w).x*255.0));Coords.w--;var voxelBit: u32=u32(voxel0);Coords=vec4i((Coords.xyz<<vec3u(1))+negD,Coords.w);var packedCoords: i32 =
Coords.x | (Coords.y<<8) | (Coords.z<<16) | (Coords.w<<24);if (max(mint.x,max(mint.y,mint.z))<min(midt.x,min(midt.y,midt.z)) &&
((1u<<voxelBit) & nodeMask) != 0) {stack[stackLevel]=packedCoords;stackLevel++;}
voxelBit ^= 0x1;packedCoords ^= 0x00001;if (max(midt.x,max(mint.y,mint.z))<min(maxt.x,min(midt.y,midt.z)) &&
((1u<<voxelBit) & nodeMask) != 0) {stack[stackLevel]=packedCoords;stackLevel++;}
voxelBit ^= 0x2;packedCoords ^= 0x00100;if (max(midt.x,max(midt.y,mint.z))<min(maxt.x,min(maxt.y,midt.z)) &&
((1u<<voxelBit) & nodeMask) != 0) {stack[stackLevel]=packedCoords;stackLevel++;}
voxelBit ^= 0x1;packedCoords ^= 0x00001;if (max(mint.x,max(midt.y,mint.z))<min(midt.x,min(maxt.y,midt.z)) &&
((1u<<voxelBit) & nodeMask) != 0) {stack[stackLevel]=packedCoords;stackLevel++;}
voxelBit ^= 0x4;packedCoords ^= 0x10000;if (max(mint.x,max(midt.y,midt.z))<min(midt.x,min(maxt.y,maxt.z)) &&
((1u<<voxelBit) & nodeMask) != 0) {stack[stackLevel]=packedCoords;stackLevel++;}
voxelBit ^= 0x1;packedCoords ^= 0x00001;if (max(midt.x,max(midt.y,midt.z))<min(maxt.x,min(maxt.y,maxt.z)) &&
((1u<<voxelBit) & nodeMask) != 0) {stack[stackLevel]=packedCoords;stackLevel++;}
voxelBit ^= 0x2;packedCoords ^= 0x00100;if (max(midt.x,max(mint.y,midt.z))<min(maxt.x,min(midt.y,maxt.z)) &&
((1u<<voxelBit) & nodeMask) != 0) {stack[stackLevel]=packedCoords;stackLevel++;}
voxelBit ^= 0x1;packedCoords ^= 0x00001;if (max(mint.x,max(mint.y,midt.z))<min(midt.x,min(midt.y,maxt.z)) &&
((1u<<voxelBit) & nodeMask) != 0) {stack[stackLevel]=packedCoords;stackLevel++;}}
#if VOXEL_MARCH_DIAGNOSTIC_INFO_OPTION
*voxel_march_diagnostic_info.heat= f32(steps)/24.0;
#endif
return false;}
fn linearizeDepth(depth: f32,near: f32,far: f32)->f32 {return (near*far)/(far-depth*(far-near));}
fn screenSpaceShadow(csOrigin: vec3f,csDirection: vec3f,csZBufferSize: vec2f,
nearPlaneZ: f32,farPlaneZ: f32,noise: f32)->f32 {
#ifdef RIGHT_HANDED
var csZDir : f32=-1.0;
#else 
var csZDir : f32=1.0;
#endif
var ssSamples: f32=SSSsamples;var ssMaxDist: f32=SSSmaxDistance;var ssStride: f32=SSSstride;var ssThickness: f32=SSSthickness;var rayLength: f32 =
select(ssMaxDist,(nearPlaneZ-csOrigin.z)/csDirection.z,
csZDir*(csOrigin.z+ssMaxDist*csDirection.z)<csZDir*nearPlaneZ);var csEndPoint: vec3f=csOrigin+rayLength*csDirection;var H0: vec4f=uniforms.projMtx*vec4f(csOrigin,1.0);var H1: vec4f=uniforms.projMtx*vec4f(csEndPoint,1.0);var Z0=vec2f(csOrigin.z ,1.0)/H0.w;var Z1=vec2f(csEndPoint.z,1.0)/H1.w;var P0=csZBufferSize*(0.5*H0.xy*Z0.y+0.5);var P1=csZBufferSize*(0.5*H1.xy*Z1.y+0.5);P1+= vec2f(select(0.0,0.01,distanceSquared(P0,P1)<0.0001));var delta: vec2f=P1-P0;var permute: bool=false;if (abs(delta.x)<abs(delta.y)) {permute=true;P0=P0.yx;P1=P1.yx;delta=delta.yx;}
var stepDirection: f32=sign(delta.x);var invdx: f32=stepDirection/delta.x;var dP: vec2f=ssStride* vec2f(stepDirection,invdx*delta.y);var dZ: vec2f=ssStride*invdx*(Z1-Z0);var opacity: f32=0.0;var P: vec2f=P0+noise*dP;var Z: vec2f=Z0+noise*dZ;var end: f32=P1.x*stepDirection;var rayZMax=csZDir*Z.x/Z.y;var sceneDepth=rayZMax;Z+=dZ;for (var stepCount: f32=0.0; 
opacity<1.0 && P.x*stepDirection<end && sceneDepth>0.0 && stepCount<ssSamples;stepCount+=1) { 
var coords=vec2i(select(P,P.yx,permute));sceneDepth=textureLoad(depthSampler,coords,0).x;sceneDepth=linearizeDepth(sceneDepth,nearPlaneZ,farPlaneZ);sceneDepth=csZDir*sceneDepth;if (sceneDepth<=0.0) {break;}
var rayZMin: f32=rayZMax;rayZMax=csZDir*Z.x/Z.y;opacity+=max(opacity,step(rayZMax,sceneDepth+ssThickness)*step(sceneDepth,rayZMin));P+=dP;Z+=dZ;}
return opacity;}
#if VOXEL_MARCH_DIAGNOSTIC_INFO_OPTION
fn voxelShadow(wsOrigin: vec3f,wsDirection: vec3f,wsNormal: vec3f,
DitherNoise: vec2f,
voxel_march_diagnostic_info: ptr<function,VoxelMarchDiagnosticInfo>)->f32 {
#else
fn voxelShadow(wsOrigin: vec3f,wsDirection: vec3f,wsNormal: vec3f,
DitherNoise: vec2f)->f32 {
#endif
var vxResolution: f32=f32(textureDimensions(voxelGridSampler,0).x);var T: vec3f;var B: vec3f;genTB(wsDirection,&T,&B);var DitherXY: vec2f=sqrt(DitherNoise.x)* vec2f(cos(2.0*PI*DitherNoise.y),
sin(2.0*PI*DitherNoise.y));var Dithering : vec3f=(uniforms.voxelBiasParameters.x*wsNormal +
uniforms.voxelBiasParameters.y*wsDirection +
DitherXY.x*T+DitherXY.y*B) /
vxResolution;var O: vec3f=0.5*wsOrigin+0.5+Dithering;var ray_vs=make_ray(O,wsDirection,0.0,10.0);var voxel_aabb: AABB3f;voxel_aabb.m_min=vec3f(0);voxel_aabb.m_max=vec3f(1);var near: f32=0;var far: f32=0;if (!ray_box_intersection(voxel_aabb,ray_vs,&near,&far)) {return 0.0;}
ray_vs.t_min=max(ray_vs.t_min,near);ray_vs.t_max=min(ray_vs.t_max,far);
#if VOXEL_MARCH_DIAGNOSTIC_INFO_OPTION
return select(0.0f,1.0f,anyHitVoxels(ray_vs,voxel_march_diagnostic_info));
#else
return select(0.0f,1.0f,anyHitVoxels(ray_vs));
#endif
}
@fragment
fn main(input: FragmentInputs)->FragmentOutputs {var nbDirs=u32(SHADOWdirs);var frameId=u32(SHADOWframe);var envRot: f32=SHADOWenvRot;var Resolution: vec2f= vec2f(textureDimensions(depthSampler,0));var currentPixel=vec2i(fragmentInputs.vUV*Resolution);var GlobalIndex =
(frameId*u32(Resolution.y)+u32(currentPixel.y))*u32(Resolution.x) +
u32(currentPixel.x);var N : vec3f=textureLoad(worldNormalSampler,currentPixel,0).xyz;if (length(N)<0.01) {fragmentOutputs.color=vec4f(1.0,1.0,0.0,1.0);return fragmentOutputs;}
var normalizedRotation: f32=envRot/(2.0*PI);var depth : f32=textureLoad(depthSampler,currentPixel,0).x;
#ifndef IS_NDC_HALF_ZRANGE
depth=depth*2.0-1.0;
#endif
var temp : vec2f=(vec2f(currentPixel)+vec2f(0.5))*2.0/Resolution -
vec2f(1.0);var VP : vec4f=uniforms.invProjMtx*vec4f(temp.x,-temp.y,depth,1.0);VP/=VP.w;N=normalize(N);var noise : vec3f=textureLoad(blueNoiseSampler,currentPixel & vec2i(0xFF),0).xyz;noise.z=fract(noise.z+goldenSequence(frameId*nbDirs));
#ifdef VOXEL_MARCH_DIAGNOSTIC_INFO_OPTION
var heat: f32=0.0f;
#endif
var shadowAccum: f32=0.001;var specShadowAccum: f32=0.001;var sampleWeight : f32=0.001;
#ifdef COLOR_SHADOWS
var totalLight: vec3f=vec3f(0.001);var shadowedLight: vec3f=vec3f(0.0);
#endif
for (var i: u32=0; i<nbDirs; i++) {var dirId: u32=nbDirs*GlobalIndex+i;var L: vec4f;var T: vec2f;{var r: vec2f=plasticSequence(frameId*nbDirs+i);r=fract(r+ vec2f(2.0)*abs(noise.xy- vec2f(0.5)));T.x=textureSampleLevel(icdfSampler,icdfSamplerSampler,vec2f(r.x,0.0),0.0).x;T.y=textureSampleLevel(icdfSampler,icdfSamplerSampler,vec2f(T.x,r.y),0.0).y;L= vec4f(uv_to_normal(vec2f(T.x-normalizedRotation,T.y)),0);
#ifndef RIGHT_HANDED
L.z*=-1.0;
#endif
}
#ifdef COLOR_SHADOWS
var lightDir: vec3f=uv_to_normal(vec2f(1.0-fract(T.x+0.25),T.y));var ibl: vec3f=textureSampleLevel(iblSampler,iblSamplerSampler,lightDir,0.0).xyz;var pdf: f32=textureSampleLevel(icdfSampler,icdfSamplerSampler,T,0.0).z;
#endif
var cosNL: f32=dot(N,L.xyz);var opacity: f32=0.0;if (cosNL>0.0) {var VP2: vec4f=VP;VP2.y*=-1.0;var unormWP : vec4f=uniforms.invViewMtx*VP2;var WP: vec3f=(uniforms.wsNormalizationMtx*unormWP).xyz;var vxNoise: vec2f=vec2f(uint2float(hash(dirId*2)),uint2float(hash(dirId*2+1)));
#ifdef VOXEL_MARCH_DIAGNOSTIC_INFO_OPTION
VoxelMarchDiagnosticInfo voxel_march_diagnostic_info;opacity=max(opacity,
uniforms.shadowOpacity.x*voxelShadow(WP,L.xyz,N,vxNoise,
voxel_march_diagnostic_info));heat+=voxel_march_diagnostic_info.heat;
#else
opacity =
max(opacity,uniforms.shadowOpacity.x*voxelShadow(WP,L.xyz,N,vxNoise));
#endif
var VL : vec3f=(uniforms.viewMtx*L).xyz;
#ifdef RIGHT_HANDED
var nearPlaneZ: f32=-2.0*uniforms.projMtx[3][2]/(uniforms.projMtx[2][2]-1.0); 
var farPlaneZ: f32=-uniforms.projMtx[3][2]/(uniforms.projMtx[2][2]+1.0);
#else
var nearPlaneZ: f32=-2.0*uniforms.projMtx[3][2]/(uniforms.projMtx[2][2]+1.0); 
var farPlaneZ: f32=-uniforms.projMtx[3][2]/(uniforms.projMtx[2][2]-1.0);
#endif
var ssShadow: f32=uniforms.shadowOpacity.y *
screenSpaceShadow(VP2.xyz,VL,Resolution,nearPlaneZ,farPlaneZ,
abs(2.0*noise.z-1.0));opacity=max(opacity,ssShadow);
#ifdef COLOR_SHADOWS
var light: vec3f=select(vec3f(0.0),vec3f(cosNL)/vec3f(pdf)*ibl,pdf>1e-6);shadowedLight+=light*opacity;totalLight+=light;
#else
var rcos: f32=1.0-cosNL;shadowAccum+=(1.0-opacity*(1.0-pow(rcos,8.0)));sampleWeight+=1.0;var VR : vec3f=abs((uniforms.viewMtx*vec4f(reflect(-L.xyz,N),0.0)).xyz);specShadowAccum+=max(1.0-(opacity*pow(VR.z,8.0)),0.0);
#endif
}
noise.z=fract(noise.z+GOLD);}
#ifdef COLOR_SHADOWS
var shadow: vec3f=(totalLight-shadowedLight)/totalLight;var maxShadow: f32=max(max(shadow.x,max(shadow.y,shadow.z)),1.0);fragmentOutputs.color=vec4f(shadow/maxShadow,1.0);
#else
#ifdef VOXEL_MARCH_DIAGNOSTIC_INFO_OPTION
fragmentOutputs.color =
vec4f(shadowAccum/sampleWeight,specShadowAccum/sampleWeight,heat/sampleWeight,1.0);
#else
fragmentOutputs.color=vec4f(shadowAccum/sampleWeight,specShadowAccum/sampleWeight,0.0,1.0);
#endif
#endif
}`;
// Sideeffect
if (!ShaderStore.ShadersStoreWGSL[name]) {
    ShaderStore.ShadersStoreWGSL[name] = shader;
}
/** @internal */
export const iblShadowVoxelTracingPixelShaderWGSL = { name, shader };
//# sourceMappingURL=iblShadowVoxelTracing.fragment.js.map