项目需要有一个成果：是当一个光点走过的路径，这个路径的位置就都亮起来的成果。
2、资料内容成果雷同这位大神的橡皮擦成果：https://forum.cocos.org/t/2-0-8/74246
可是，项目标需求还要颠末的路径周围有恍惚的外边——也就是从中心到边沿越来越暗。
所以对付警惕了网上大神的shader例子，雷同以下的示例：
在大神的肩膀上做了一些窜改，来实现项目标需求。
3、项目示例以下是我本身的测试项目标示例：
（请忽略这渣渣的画质，懒得装录屏软件了）
4、项目代码SliderPointLight.ts
const { ccclass, property } = cc._decorator; @ccclass export default class Follow_spot extends cc.Component { @property(cc.Node) bg: cc.Node = null; material: cc.Material = null; center: number[] = [0.5, 0.5]; testArr: number[] = []; onLoad() { this.material = this.bg.getComponent(cc.Sprite).getMaterial(0); this.material.setProperty('wh_ratio', this.bg.width / this.bg.height); this.material.setProperty('center', this.center); //js 中最重要是这一句,这里参数是数组长度*数组里向量的维度 this.material.setProperty('colorArr', new Float32Array(400)); //这里配置的时候需要把数组里向量的分量展开到一个一维数组 this.material.setProperty('colorArr', []); this.bg.on(cc.Node.EventType.TOUCH_MOVE, this.touchMoveEvent, this); } touchMoveEvent(evt: cc.Event.EventTouch) { this.center[0] = evt.getLocation().x / this.bg.width; this.center[1] = 1 - evt.getLocation().y / this.bg.height; console.log(this.center); this.material.setProperty('center', this.center); if (this.testArr.length >= 400) { this.testArr.shift(); this.testArr.shift(); } this.testArr.push(this.center[0]); this.testArr.push(this.center[1]); //js 中最重要是这一句,这里参数是数组长度*数组里向量的维度 this.material.setProperty('colorArr', new Float32Array(this.testArr)); //这里配置的时候需要把数组里向量的分量展开到一个一维数组 this.material.setProperty('colorArr', this.testArr); } } SliderPointLight.effect CCEffect % { techniques: -passes: -vert: vs frag: fs blendState: targets: -blend: true rasterizerState: cullMode: none properties: texture: { value: white } wh_ratio: { value: 1.78, editor: { tooltip: "宽高比" } } blur: { value: 0.35, editor: { tooltip: "光圈恍惚水平" } } radius: { value: 0.5, editor: { tooltip: "光圈半径" } } center: { value: [0.5, 0.5], editor: { tooltip: "光圈起点" } } colorArr: { value: [0.5, 0.5, 0.5, 0.5] } } % CCProgram vs % { precision highp float; #include <cc-global> #include <cc-local> in vec3 a_position; in vec4 a_color; out vec4 v_color; #if USE_TEXTURE in vec2 a_uv0; out vec2 v_uv0; #endif void main() { vec4 pos = vec4(a_position, 1); #if CC_USE_MODEL pos = cc_matViewProj * cc_matWorld * pos; #else pos = cc_matViewProj * pos; #endif #if USE_TEXTURE v_uv0 = a_uv0; #endif v_color = a_color; gl_Position = pos; } } % CCProgram fs % { precision highp float; #include <alpha-test> in vec4 v_color; #if USE_TEXTURE in vec2 v_uv0; uniform sampler2D texture; #endif uniform ARGS { float radius; float blur; vec2 center; float wh_ratio; }; //effect界说 uniform Metaball { vec4 colorArr[100]; }; void main() { vec4 o = vec4(1, 1, 1, 0); o *= texture(texture, v_uv0); o *= v_color; float circle = radius * radius; for (int i = 0; i < 100; i++) { float colorX = colorArr[i].x; float colorY = colorArr[i].y; float rx = colorX * wh_ratio; float ry = colorY; float dis = (v_uv0.x * wh_ratio - rx) * (v_uv0.x * wh_ratio - rx) + (v_uv0.y - ry) * (v_uv0.y - ry); o.a = smoothstep(circle, circle - blur, dis) + o.a; } gl_FragColor = o; } }%