微信小游戏 彩色试管 倒水游戏 逻辑 （二）

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定义一个 Water class

1. **定义接口和枚举**：
   - `WaterInfo` 接口定义了水的颜色、高度等信息。
   - `PourAction` 枚举定义了水的倒动状态，包括无动作、加水、倒水。

2. **类 `Water`**：
   - `Water` 类继承自 `Component`，用于控制水杯中的水。
   - 包含了私有变量 `_action` 用于记录当前倒动状态，`infos` 数组用于存储每一层水的信息，`stopIdx` 和 `curIdx` 分别记录停止倒水和当前水层的索引。
   -初始化方法 `initInfos` 和 `addInfo`，用于设置和添加水层信息。
   - `setPourOutCallback` 和 `setPourInCallback` 方法，用于设置倒水和加水的回调函数。
   - `getPourStartAngle` 和 `getPourEndAngle` 方法，用于计算倒水的起始和结束角度。
   - `onStartPour` 方法，用于开始倒水。
   - `update` 方法，用于每帧更新水的状态。
   - `addStep` 和 `pourStep` 方法，用于每帧增加或减少水的高度。
   - `initSizeColor` 和 `updateAngleHeight` 方法，用于初始化和更新材质属性。
   - showDebugCenter` 方法，用于调试显示水面中心点。

3. **辅助函数**：
   - `angle2radian` 和 `radian2angle` 函数用于角度和弧度的转换。

### 实现原理

- **材质和着色器**：通过 `Material` 和 `EffectAsset` 来应用自定义的着色器效果，模拟水的倒动效果。
- **物理模拟**：通过每帧更新水的高度来模拟水的流动，使用三角函数计算倾斜角度和水面中心点。
- **回调函数**：通过设置回调函数，可以在倒水和加水的特定时刻执行特定的操作。

### 用途

这段代码可以用于游戏或应用中模拟水杯中水的倒动效果，例如在游戏中模拟饮料的倒动，或者在应用中模拟水杯的倒水效果。

import { Color, Component, EffectAsset, Label, Material, Sprite, UITransform, v2,Node, v3, _decorator, Vec4, color, v4, log } from "cc";
import { DEV, EDITOR } from "cc/env";const { ccclass, property, requireComponent, executeInEditMode, disallowMultiple, executionOrder } = _decorator;export interface WaterInfo{colorId:number,color:Color,//颜色height:number,//默认情况下，占杯子的高度
}const MAX_ARR_LEN = 6;enum PourAction{none,/**往里加水 */in,/**向外倒水 */out,
} @ccclass
@requireComponent(Sprite)
@executeInEditMode
@disallowMultiple
@executionOrder(-100)
export default class Water extends Component {private _action:PourAction = PourAction.none;private infos:WaterInfo[] = [];/**到这里停止倒水 */private stopIdx = -1;/**当前是有几层水 */private curIdx = 0;/**节点高宽比 */private _ratio:number = 1;@property(EffectAsset)private effect:EffectAsset = null;@property private _skewAngle: number = 0;@property({ tooltip: DEV && '旋转角度' })public get skewAngle() { return this._skewAngle; }public set skewAngle(value: number) { value = Math.round(value*100)/100;// log("angle",value)this._skewAngle = value; this.updateAngleHeight();}private _material: Material = null;private get material(){if(this._material==null){let sp = this.node.getComponent(Sprite);if(sp){if (sp.spriteFrame) sp.spriteFrame.packable = false;// 生成并应用材质if(this.effect){this._material = new Material();this._material.initialize({effectAsset:this.effect})sp.setMaterial( this._material,0);}this._material = sp.getSharedMaterial(0)this._material.setProperty("mainTexture",sp.spriteFrame.texture)}}return this._material}protected onLoad() {this._ratio = this.node.getComponent(UITransform).height/this.node.getComponent(UITransform).width;}public initInfos(infos:Array<WaterInfo>){this.infos = infos;this.curIdx = this.infos.length-1;this.initSizeColor();this.updateAngleHeight();}private addHeight = 0;public addInfo(info:WaterInfo){this.addHeight = info.height;info.height = 0;this.infos.push(info);this._action = PourAction.in;this.curIdx = this.infos.length-1;this.initSizeColor();}private onOutStart:Function = null;private onOutFinish:Function = null;public setPourOutCallback(onOutStart:Function,onOutFinish:Function){this.onOutStart = onOutStart;this.onOutFinish = onOutFinish;}private onInFInish:Function = null;public setPourInCallback(onInFInish:Function){this.onInFInish = onInFInish;}/*** 倾斜到哪个角度开始往外边倒水*/public getPourStartAngle(){let _height = 0;for(let i=0;i<=this.curIdx;i++){_height+=this.infos[i].height;}return this.getCriticalAngleWithHeight(_height);}/*** 倾斜到哪个角度开始停止倒水（当前颜色的水倒完了）*/public getPourEndAngle(){this.stopIdx = this.curIdx-this.getTopSameColorNum();let _height = 0;for(let i=0;i<=this.stopIdx;i++){_height+=this.infos[i].height;}return this.getCriticalAngleWithHeight(_height);}/**获取某一高度的水刚好碰到瓶口的临界倾斜角度 */private getCriticalAngleWithHeight(_height){let ret = 0;if(_height==0){ret = 90;return ret;}if(_height<0.5){//水的体积小于杯子的一半,先碰到下瓶底let tanVal = this._ratio/(_height*2.0);ret = Math.atan(tanVal);}else{let tanVal = 2.0*this._ratio*(1.0-_height); ret = Math.atan(tanVal);}ret = radian2angle(ret);return ret;}private getTopSameColorNum(){let sameColorNum = 0;let colorId=null;for(let i=this.curIdx;i>=0;i--){if(colorId==null){sameColorNum++;colorId = this.infos[i].colorId;}else if(this.infos[i].colorId==colorId){sameColorNum++;}else{break;}}return sameColorNum}/*** 开始倒水* 一直倒水直到不同颜色的水到达瓶口，为当前最大能倾斜的角度* @returns 返回值为倾斜角度的绝对值*/public onStartPour(){this._action = PourAction.out;this.stopIdx = this.curIdx-this.getTopSameColorNum();}update(){if(this._action==PourAction.out){this.pourStep();}else if(this._action==PourAction.in){this.addStep()}}/*** 每帧调用，升高水面高度*/addStep(){if(this.curIdx<0){return;}let info = this.infos[this.curIdx];info.height = Math.round((info.height + 0.005)*1000)/1000;// log("--------info.height",info.height)if(info.height>=this.addHeight){info.height = this.addHeight;this._action = PourAction.none;if(this.onInFInish){this.onInFInish();this.onInFInish = null;}}this.updateAngleHeight();}/*** * 每帧调用* * 降低水面高度 */pourStep(){if(this.curIdx<0){this._action = PourAction.none;return;}let _height = 0;for(let i=0;i<=this.curIdx;i++){_height+=this.infos[i].height;}let is_top = false;let angle = (this.skewAngle%360) * Math.PI / 180.0let _t = Math.abs(Math.tan(angle));if(_height<0.5){//水的体积小于杯子的一半,先碰到下瓶底is_top = _t>(this._ratio)/(_height*2.0);}else{is_top = _t>2.0*this._ratio*(1.0-_height);}let info = this.infos[this.curIdx];if(!is_top){//没到瓶口，不往下倒if(info.height<0.05){//可能还留了一点点水,要继续倒出去}else{return;}}if(this.onOutStart){this.onOutStart();this.onOutStart = null;}info.height = Math.round((info.height - 0.005)*1000)/1000;if(info.height<0.01){info.height = 0;this.infos.pop();this.curIdx--;// log("------this.curIdx",this.curIdx,this.stopIdx)if(this.curIdx==this.stopIdx){if(this.onOutFinish){this.onOutFinish();this.onOutFinish = null;}this._action = PourAction.none;}}// log("this.curIdx",this.curIdx,"info.height",info.height.toFixed(2),"angle",this.skewAngle.toFixed(2))this.updateAngleHeight();}private initSizeColor(){for(let i=0;i<this.infos.length;i++){const c = this.infos[i].color; this.material.setProperty('color'+i, c);}let size = v2(this.node.getComponent(UITransform).width,this.node.getComponent(UITransform).height)this.material.setProperty('sizeRatio', size.y/size.x);this.material.setProperty('waveType', 0);this.material.setProperty("layerNum",this.infos.length)}private updateAngleHeight() { for(let i=0;i<6;i++){if(i<this.infos.length){let h = this.infos[i].height;this.material.setProperty('height'+i, h);}else{this.material.setProperty('height'+i, 0);}}let radian = angle2radian(this._skewAngle)this.material.setProperty('skewAngle', radian*1.0);let waveType = 0.0;if(this._action==PourAction.in){waveType = 1.0;}else if(this._action==PourAction.out){waveType = 2.0;}this.material.setProperty('waveType', waveType);this.material.setProperty("layerNum",this.infos.length)this.showDebugCenter();}private dot:Node = null;/**显示水面的中心点，调试shader脚本用 */private showDebugCenter(){if(EDITOR){return;}if(this.dot==null){this.dot = new Node();this.dot.parent = this.node;this.dot.addComponent(UITransform)let label = this.dot.addComponent(Label);label.string = "·";label.fontSize = 60;label.color = Color.RED;}let ratio = this.node.getComponent(UITransform).height/this.node.getComponent(UITransform).width;let angle = angle2radian(this.skewAngle);let _height = 0;if(this.curIdx>=this.infos.length){return}for(let i=0;i<=this.curIdx;i++){_height+=this.infos[i].height;}let toLeft = Math.sin(angle)>=0.0;let center = v2(0.5,1.0-_height);//水面倾斜时，以哪个店为中心店let _t = Math.abs(Math.tan(angle));if(_height<=0.5){//水的体积小于杯子的一半,先碰到下瓶底let is_bottom = _t>ratio*2.0*_height;//倾斜角度达到瓶底if(is_bottom){center.x = Math.sqrt((2.0*_height/_t)*ratio)/2.0;center.y = 1.0 - Math.sqrt((2.0*_height*_t)/ratio)/2.0;let is_top = _t>(ratio)/(_height*2.0);//倾斜角度达到瓶口if(is_top){center.y = 0.5;center.x = _height;}}if(!toLeft){center.x = 1.0-center.x;}if(Math.abs(center.x-0.25)<0.01){let i = 0;}// log("aa-------center",center.x.toFixed(2),center.y.toFixed(2));}else{//水比较多，先碰到上瓶底let is_top = _t>2.0*ratio*(1.0-_height);if(is_top){center.x = Math.sqrt(2.0*ratio*(1.0-_height)/_t)/2.0;center.y = Math.sqrt(2.0*ratio*(1.0-_height)*_t)/2.0/ratio;let is_bottom = _t>ratio/(2.0*(1.0-_height));if(is_bottom){center.y = 0.5;center.x = 1.0-_height;}}else{}if(toLeft){center.x = 1.0-center.x;}// log("bb-------center",center.x.toFixed(2),center.y.toFixed(2));}center.x = center.x - 0.5;center.y = -center.y + 0.5;let pt = v3(center.x*this.node.getComponent(UITransform).width,center.y*this.node.getComponent(UITransform).height);this.dot.position = pt;}
}function angle2radian(angle:number){while(angle>360){angle-=360;}while(angle<-360){angle+=360;}return (angle%360) * Math.PI / 180.0;
}function radian2angle(radian:number) {return radian/Math.PI*180;
}