Cesium 自定义Material 系列 （六）

• 对于扩散圆效果 我们先定义一下他的interface, 方便使用的人知道他的调用参数

• export interface PMaterialDiffusionCircle{
• color?: any,
• speed?: number,
• type?: EMaterialDiffusionCircle,
• }
•  
• export enum EMaterialDiffusionCircle {
• normal,//标准
• glow,//辉光
• trail//拖尾
• }

• 对于扩散圆我们叫 MaterialDiffusionCircle

``javascript import { MaterialProperty } from "./MaterialProperty"; const defaultOption: PMaterialDiffusionCircle = { color: new Cesium.Color(1.0, 0.0, 0.0, 0.5), speed: 10, type: EMaterialDiffusionCircle.normal//是否微光 } //扩散圆效果 export class MaterialDiffusionCircle extends MaterialProperty { public _getType(option: PMaterialDiffusionCircle) { // 由于参数需要动态变动，所以count有变动，认为是新着色器 return "MaterialWaterRipple" + option.type } constructor(option = defaultOption) { super(MaterialDiffusionCircle.prototype, defaultOption, option); } protected getSource(option: PMaterialDiffusionCircle): string { const { type = EMaterialDiffusionCircle.normal } = option; if (type === EMaterialDiffusionCircle.glow) { return this._glow(); } else { return this._normal(type); } } //标准的或者拖尾效果 private _normal(type: EMaterialDiffusionCircle) { let trail = -0.01; if (type === EMaterialDiffusionCircle.trail) { trail = -0.1; } return
uniform vec4 color;
uniform float speed;

• float circle(vec2 uv, float r, float blur) {
• float d = length(uv) * 2.0;
• float c = smoothstep(r+blur, r, d);
• return c;
• }
•  
• czm_material czm_getMaterial(czm_materialInput materialInput)
• {
• czm_material material = czm_getDefaultMaterial(materialInput);
• vec2 st = materialInput.st - .5;
• material.diffuse = color.rgb;
• material.emission = vec3(0);
• float time =fract(czm_frameNumber * speed / 1000.0);
• float s = 0.5;
• float radius = smoothstep(.0, s, time) * 0.5;

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