three-stdlib/objects/GroundProjectedEnv.js

stand-alone library of threejs examples

import { Mesh, IcosahedronGeometry, ShaderMaterial, DoubleSide } from "three";
import { version } from "../_polyfill/constants.js";
const isCubeTexture = (def) => def && def.isCubeTexture;
class GroundProjectedEnv extends Mesh {
  constructor(texture, options) {
    var _a, _b;
    const isCubeMap = isCubeTexture(texture);
    const w = (_b = isCubeMap ? (_a = texture.image[0]) == null ? void 0 : _a.width : texture.image.width) != null ? _b : 1024;
    const cubeSize = w / 4;
    const _lodMax = Math.floor(Math.log2(cubeSize));
    const _cubeSize = Math.pow(2, _lodMax);
    const width = 3 * Math.max(_cubeSize, 16 * 7);
    const height = 4 * _cubeSize;
    const defines = [
      isCubeMap ? "#define ENVMAP_TYPE_CUBE" : "",
      `#define CUBEUV_TEXEL_WIDTH ${1 / width}`,
      `#define CUBEUV_TEXEL_HEIGHT ${1 / height}`,
      `#define CUBEUV_MAX_MIP ${_lodMax}.0`
    ];
    const vertexShader = (
      /* glsl */
      `
        varying vec3 vWorldPosition;
        void main() 
        {
            vec4 worldPosition = ( modelMatrix * vec4( position, 1.0 ) );
            vWorldPosition = worldPosition.xyz;
            
            gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );
        }
        `
    );
    const fragmentShader = defines.join("\n") + /* glsl */
    `
        #define ENVMAP_TYPE_CUBE_UV
        varying vec3 vWorldPosition;
        uniform float radius;
        uniform float height;
        uniform float angle;
        #ifdef ENVMAP_TYPE_CUBE
            uniform samplerCube map;
        #else
            uniform sampler2D map;
        #endif
        // From: https://www.shadertoy.com/view/4tsBD7
        float diskIntersectWithBackFaceCulling( vec3 ro, vec3 rd, vec3 c, vec3 n, float r ) 
        {
            float d = dot ( rd, n );
            
            if( d > 0.0 ) { return 1e6; }
            
            vec3  o = ro - c;
            float t = - dot( n, o ) / d;
            vec3  q = o + rd * t;
            
            return ( dot( q, q ) < r * r ) ? t : 1e6;
        }
        // From: https://www.iquilezles.org/www/articles/intersectors/intersectors.htm
        float sphereIntersect( vec3 ro, vec3 rd, vec3 ce, float ra ) 
        {
            vec3 oc = ro - ce;
            float b = dot( oc, rd );
            float c = dot( oc, oc ) - ra * ra;
            float h = b * b - c;
            
            if( h < 0.0 ) { return -1.0; }
            
            h = sqrt( h );
            
            return - b + h;
        }
        vec3 project() 
        {
            vec3 p = normalize( vWorldPosition );
            vec3 camPos = cameraPosition;
            camPos.y -= height;
            float intersection = sphereIntersect( camPos, p, vec3( 0.0 ), radius );
            if( intersection > 0.0 ) {
                
                vec3 h = vec3( 0.0, - height, 0.0 );
                float intersection2 = diskIntersectWithBackFaceCulling( camPos, p, h, vec3( 0.0, 1.0, 0.0 ), radius );
                p = ( camPos + min( intersection, intersection2 ) * p ) / radius;
            } else {
                p = vec3( 0.0, 1.0, 0.0 );
            }
            return p;
        }
        #include <common>
        #include <cube_uv_reflection_fragment>
        void main() 
        {
            vec3 projectedWorldPosition = project();
            
            #ifdef ENVMAP_TYPE_CUBE
                vec3 outcolor = textureCube( map, projectedWorldPosition ).rgb;
            #else
                vec3 direction = normalize( projectedWorldPosition );
                vec2 uv = equirectUv( direction );
                vec3 outcolor = texture2D( map, uv ).rgb;
            #endif
            gl_FragColor = vec4( outcolor, 1.0 );
            #include <tonemapping_fragment>
            #include <${version >= 154 ? "colorspace_fragment" : "encodings_fragment"}>
        }
        `;
    const uniforms = {
      map: { value: texture },
      height: { value: (options == null ? void 0 : options.height) || 15 },
      radius: { value: (options == null ? void 0 : options.radius) || 100 }
    };
    const geometry = new IcosahedronGeometry(1, 16);
    const material = new ShaderMaterial({
      uniforms,
      fragmentShader,
      vertexShader,
      side: DoubleSide
    });
    super(geometry, material);
  }
  set radius(radius) {
    this.material.uniforms.radius.value = radius;
  }
  get radius() {
    return this.material.uniforms.radius.value;
  }
  set height(height) {
    this.material.uniforms.height.value = height;
  }
  get height() {
    return this.material.uniforms.height.value;
  }
}
export {
  GroundProjectedEnv
};
//# sourceMappingURL=GroundProjectedEnv.js.map