@doegis/core/chunks/Clouds.glsl.js

DOE GIS API

import{lerp as t}from"../core/mathUtils.js";import{isSome as e}from"../core/maybe.js";import{c as a}from"./mat3f64.js";import{s as o}from"./vec2.js";import{a as i}from"./vec2f64.js";import{cloudPresets as s}from"../views/3d/environment/CloudsPresets.js";import{RayMarchingSteps as n}from"../views/3d/environment/CloudsTechniqueConfiguration.js";import{ATLAS_SIZE as r,TILE_ROWS as l,TILE_SIZE as c,TEXTURE_SCALE as d,WEATHER_MAP_SCALE as u}from"../views/3d/environment/NoiseTextureAtlasDimensions.js";import{ScreenSpacePass as f}from"../views/3d/webgl-engine/core/shaderLibrary/ScreenSpacePass.glsl.js";import{Float2PassUniform as m}from"../views/3d/webgl-engine/core/shaderModules/Float2PassUniform.js";import{FloatPassUniform as h}from"../views/3d/webgl-engine/core/shaderModules/FloatPassUniform.js";import{NoParameters as p,glsl as g}from"../views/3d/webgl-engine/core/shaderModules/interfaces.js";import{Matrix3DrawUniform as v}from"../views/3d/webgl-engine/core/shaderModules/Matrix3DrawUniform.js";import{ShaderBuilder as y}from"../views/3d/webgl-engine/core/shaderModules/ShaderBuilder.js";import{Texture2DPassUniform as w}from"../views/3d/webgl-engine/core/shaderModules/Texture2DPassUniform.js";class S extends p{constructor(){super(...arguments),this.cloudRadius=0,this.cloudSize=0,this.detailSize=0,this.absorption=0,this.density=0,this.smoothness=0,this.cloudHeight=0,this.coverage=0,this.raymarchingSteps=s.default.raymarchingSteps,this.weatherTile=i()}}class x extends p{constructor(){super(...arguments),this.viewMatrix=a()}}function b(a){const i=new y;i.include(f,!1);const s=i.fragment;return s.uniforms.add([new h("cloudRadius",(t=>t.cloudRadius)),new h("power",(e=>t(35,120,e.absorption))),new h("sigmaE",(t=>1+t.absorption)),new h("density",(e=>t(0,.3,e.density))),new h("cloudSize",(e=>t(0,.02,Math.max(.01,1-e.cloudSize)))),new h("detailSize",(e=>t(0,.2,Math.max(.01,1-e.detailSize)))),new h("smoothness",(e=>t(0,.5,1-e.smoothness))),new h("cloudHeight",(e=>t(0,1500,e.cloudHeight))),new h("coverage",(t=>t.coverage)),new v("view",(t=>t.viewMatrix)),new w("cloudShapeTexture",(t=>e(t.noiseTexture)?t.noiseTexture.textureAtlas:null)),new m("cloudVariables",(t=>o(D,t.coverage,t.absorption)))]),s.constants.add("halfCubeMapSize","float",.5*a.cubeMapSize),s.code.add(g`
    const int STEPS = ${a.steps===n.SIXTEEN?g`16`:a.steps===n.HUNDRED?g`100`:g`200`};
    const int STEPS_LIGHT = 6;
    const float stepL = 300.0 / float(STEPS_LIGHT);
    const float cloudStart = 1500.0;

    vec3 rayDirection(vec2 fragCoord) {
      vec2 xy = fragCoord - halfCubeMapSize;
      return normalize(vec3(-xy, -halfCubeMapSize));
    }

    float remap(float x, float low1, float high1, float low2, float high2) {
      return low2 + (x - low1) * (high2 - low2) / (high1 - low1);
    }

    float saturate(float x) {
      return clamp(x, 0.0, 1.0);
    }`),s.code.add(g`
    float getCloudShape(vec3 pos, float pOffset) {
      const float textureWidth = ${g.float(r)};
      const float dataWidth = ${g.float(r)};
      const float tileRows = ${g.float(l)};
      const vec3 atlasDimensions = vec3(${g.float(c)}, ${g.float(c)}, tileRows * tileRows);

      //Change from Y being height to Z being height
      vec3 p = float(${g.float(d)}) * pos.xzy;

      //Pixel coordinates of point in the 3D data
      vec3 coord = vec3(mod(p - pOffset * atlasDimensions, atlasDimensions));
      float f = fract(coord.z);
      float level = floor(coord.z);
      float tileY = floor(level / tileRows);
      float tileX = level - tileY * tileRows;

      //The data coordinates are offset by the x and y tile, the two boundary cells between each tile pair and the initial boundary cell on the first row/column
      vec2 offset = atlasDimensions.x * vec2(tileX, tileY) + 2.0 * vec2(tileX, tileY) + 1.0;
      vec2 pixel = coord.xy + offset;
      vec2 data = texture2D(cloudShapeTexture, mod(pixel, dataWidth) / textureWidth).xy;

      return 1.0 - mix(data.x, data.y, f);
    }

    float getCloudMap(vec2 p){
      // Non-power-of-two textures can't be tiled using WebGL1
      // Get fractional part of uv to tile
      // Shift the texture center to origin to avoid seam artifacts
      vec2 uv = fract((${g.float(u)} * p) / ${g.float(r)} + 0.5);

      return texture2D(cloudShapeTexture, uv).a;
    }
    `),s.code.add(g`float clouds(vec3 p) {
float cloud = saturate(0.5 * mix(0.0, 1.0, min(2.0 * coverage, 1.0)));
if (cloud <= 0.0) {
return 0.0;
}
float cloudMap = getCloudMap(cloudSize * p.xy);
cloud = mix(cloud, min(2.0 * (coverage), 1.0) * cloudMap, min(2.0 * (1.0 - coverage), 1.0));
if (cloud <= 0.0) {
return 0.0;
}
float shape = getCloudShape(8.0 * cloudSize * p, 0.0);
cloud = saturate(remap(cloud, smoothness * shape, 1.0, 0.0, 1.0));
if (cloud <= 0.0) {
return 0.0;
}
float heightFraction = saturate((length(p) - cloudRadius - cloudStart) / cloudHeight);
cloud *= saturate(remap(heightFraction, 0.0, 0.25, 0.0, 1.0)) * smoothstep(1.0, 0.25, heightFraction);
if (cloud <= 0.0) {
return 0.0;
}
return density * saturate(remap(cloud, 0.35 * smoothness * getCloudShape(detailSize * p, 0.0), 1.0, 0.0, 1.0));
}`),s.code.add(g`vec2 sphereIntersections(vec3 start, vec3 dir, float radius) {
float a = dot(dir, dir);
float b = 2.0 * dot(dir, start);
float c = dot(start, start) - (radius * radius);
float d = (b * b) - 4.0 * a * c;
if (d < 0.0) {
return vec2(1e5, -1e5);
}
return vec2((-b - sqrt(d)) / (2.0 * a), (-b + sqrt(d)) / (2.0 * a));
}
float HenyeyGreenstein(float g, float costh) {
return (1.0 / (4.0 * 3.1415))  * ((1.0 - g * g) / pow(1.0 + g * g - 2.0 * g * costh, 1.5));
}`),s.code.add("\n    float multipleOctaves(float extinction, float mu, float stepL) {\n      float attenuation = 1.0;\n      float contribution = 1.0;\n      float phaseAttenuation = 1.0;\n      float luminance = 0.0;\n\n      for (int i = 0; i < 4; i++) {\n        float phase = mix(HenyeyGreenstein(0.0, mu), HenyeyGreenstein(0.3 * phaseAttenuation, mu), 0.7);\n        luminance += contribution * phase * exp(-stepL * extinction * sigmaE * attenuation);\n        attenuation *= 0.2;\n        contribution *= 0.6;\n        phaseAttenuation *= 0.5;\n      }\n\n      return luminance;\n    }"),s.code.add(g`float lightRay(vec3 org, vec3 p, float phaseFunction, float mu, vec3 sunDirection) {
float lightRayDensity = clouds(p);
lightRayDensity += clouds(p + sunDirection * 1.0 * stepL);
lightRayDensity += clouds(p + sunDirection * 2.0 * stepL);
lightRayDensity += clouds(p + sunDirection * 3.0 * stepL);
lightRayDensity += clouds(p + sunDirection * 4.0 * stepL);
lightRayDensity += clouds(p + sunDirection * 5.0 * stepL);
float beersLaw = multipleOctaves(lightRayDensity, mu, stepL);
return mix(beersLaw * 2.0 * (1.0 - (exp(-stepL * lightRayDensity * 2.0 * sigmaE ))), beersLaw, 0.5 + 0.5 * mu);
}`),s.code.add(g`float mainRay(vec3 org, vec3 dir, vec3 sunDirection, float distToStart, float totalDistance, out float totalTransmittance) {
if (dir.z < 0.0) {
return 0.0;
}
totalTransmittance = 1.0;
float stepS = totalDistance / float(STEPS);
float cameraHeight = length(org);
float mu = 0.5 + 0.5 * dot(sunDirection, dir);
float phaseFunction = mix(HenyeyGreenstein(-0.3, mu), HenyeyGreenstein(0.3, mu), 0.7);
vec3 p = org + distToStart  * dir;
float dist = distToStart;
float shading = 0.0;
for (int i = 0; i < STEPS; i++) {
float sampleDensity = clouds(p);
float sampleSigmaE = sampleDensity * sigmaE;
if (sampleDensity > 0.0 ) {
float ambient = mix((1.2), (1.6), saturate((length(p) - cloudRadius - cloudStart) / cloudHeight));
float luminance = sampleDensity * (ambient + power * phaseFunction * lightRay(org, p, phaseFunction, mu, sunDirection));
float transmittance = exp(-sampleSigmaE * stepS);
shading += totalTransmittance * (luminance - luminance * transmittance) / sampleSigmaE;
totalTransmittance *= transmittance;
if (totalTransmittance <= 0.001) {
totalTransmittance = 0.0;
break;
}
}
dist += stepS;
p = org + dir * dist;
}
return shading;
}`),s.code.add(g`void main() {
if (coverage ==  0.0) {
gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0);
return;
}
vec3 rayDir = rayDirection(gl_FragCoord.xy);
rayDir = normalize(view * rayDir);
vec3 viewPos = vec3(0, 0, cloudRadius + 1.0);
bool hitsPlanet = rayDir.z < 0.0;
float hazeFactor = smoothstep(-0.01, mix(0.0, 0.075, cloudVariables.x), abs(dot(rayDir, vec3(0, 0, 1))));
float totalTransmittance = 1.0;
float shading = 0.0;
if (hitsPlanet) {
shading = clamp(1.0 - cloudVariables.y, 0.6, 1.0) * (1.0 - hazeFactor);
totalTransmittance = hazeFactor;
gl_FragColor = vec4(shading, totalTransmittance, shading, totalTransmittance);
return;
}
vec2 rayStartIntersect = sphereIntersections(viewPos, rayDir, cloudRadius + cloudStart);
vec2 rayEndIntersect = sphereIntersections(viewPos, rayDir, cloudRadius + cloudStart + cloudHeight);
float distToStart = rayStartIntersect.y;
float totalDistance = rayEndIntersect.y - distToStart;
vec3 sunDirection = normalize(vec3(0, 0, 1));
shading = 0.5 * mainRay(viewPos, rayDir, sunDirection, distToStart, totalDistance, totalTransmittance);
shading = mix(clamp(1.0 - cloudVariables.y, 0.6, 1.0), shading, hazeFactor);
totalTransmittance = mix(0.0, totalTransmittance, hazeFactor);
gl_FragColor = vec4(shading, totalTransmittance, shading, totalTransmittance);
}`),i}const D=i(),T=Object.freeze(Object.defineProperty({__proto__:null,CloudsDrawParameters:x,CloudsPassParameters:S,build:b},Symbol.toStringTag,{value:"Module"}));export{S as C,x as a,T as b,b as c};