Cesium 与 Babylon.js 可视化 glsl 特效篇（十七）

Posted 2023-03-15 haibalai

我决定不从Babylonjs 基础来讲了 直接整合cesium与babylonjs可视化来讲

我整合一个类库 后续不断更新中

• npm i @haibalai/cesium-babylonjs

 

初始化cesium -babylonjs 类库， map 是cesium 的viewer对象

• import  BabylonMapManager from "@haibalai/cesium-babylonjs";
• BabylonMapManager.init(map);

 

添加特效

• import BabylonMapManager  from "@haibalai/cesium-babylonjs";
• const fragmentShader = `
• precision highp float;
• uniform float iTime;
• uniform vec2 iResolution;
• varying vec2 vUv;
• // Rand value between 0 and 1
• floatrand(vec2 p)
• return fract(sin(dot(p, vec2(12.543,514.123)))*4732.12);
• // Value noise
• floatnoise(vec2 p)
• vec2 f = smoothstep(0.0, 1.0, fract(p));
• vec2 i = floor(p);
• float a = rand(i);
• float b = rand(i+vec2(1.0,0.0));
• float c = rand(i+vec2(0.0,1.0));
• float d = rand(i+vec2(1.0,1.0));
• return mix(mix(a, b, f.x), mix(c, d, f.x), f.y);
• // Fractal noise
• floatfbm(vec2 p)
• float a = 0.5;
• float r = 0.0;
• for (int i = 0; i < 8; i++)
• r += a*noise(p);
• a *= 0.5;
• p *= 2.0;
• return r;
• // Lasers originating from a central point
• floatlaser(vec2 p, int num)
• float r = atan(p.x, p.y);
• float sn = sin(r*float(num)+iTime);
• float lzr = 0.5+0.5*sn;
• lzr = lzr*lzr*lzr*lzr*lzr;
• float glow = pow(clamp(sn, 0.0, 1.0),100.0);
• return lzr+glow;
• // Mix of fractal noises to simulate fog
• floatclouds(vec2 uv)
• vec2 t = vec2(0,iTime);
• float c1 = fbm(fbm(uv*3.0)*0.75+uv*3.0+t/3.0);
• float c2 = fbm(fbm(uv*2.0)*0.5+uv*7.0+t/3.0);
• float c3 = fbm(fbm(uv*10.0-t)*0.75+uv*5.0+t/6.0);
• float r = mix(c1, c2, c3*c3);
• return r*r;
• voidmain(void)
• vec2 uv = (vUv - 0.4) * 2.0;
• vec2 hs = iResolution.xy/iResolution.y*0.5;
• vec2 uvc = uv-hs;
• float l = (1.0 + 3.0*noise(vec2(15.0-iTime)))
• * laser(vec2(uv.x+0.5, uv.y*(0.5 + 10.0*noise(vec2(iTime/5.0))) + 0.1), 15);
• l += fbm(vec2(2.0*iTime))
• * laser(vec2(hs.x-uvc.x-0.2, uv.y+0.1), 25);
• l += noise(vec2(iTime-73.0))
• * laser(vec2(uvc.x, 1.0-uv.y+0.5), 30);
• float c = clouds(uv);
• vec4 col = vec4(0, 1, 0, 1)*(uv.y*l+uv.y*uv.y)*c;
• gl_FragColor = pow(col, vec4(0.75));
• `;
• const vertexShader = `
• attribute vec3 position;
• attribute vec2 uv;
• varying vec2 vUv;
• uniform mat4 worldViewProjection;
• voidmain()
• vUv = uv;
• gl_Position = worldViewProjection * vec4(position, 1.0);
• `
• let map = baseMapCtrl.getViewer(this.mapId);
• let scene = BabylonMapManager.getScene(map);

Cesium 与 Babylon.js 可视化 glsl 特效篇（十七） － 小专栏