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嗨，对不起，但我的数学和物理太弱了，所以我尝试了很多次，但每次我失败时，我都需要你的帮助来完成我的应用程序，请将此圈子转换为心

import android.graphics.Bitmap;
public class Circle {
float origRadius,deltaRadius,radius,origX,deltaX,x,origY,deltaY,y;
int color,alpha,steps,currentStep;
Bitmap bitmap;

public Circle(float xCenter, float yCenter, float radius,
        int color, int steps) {
    this.x = xCenter;
    this.origX = xCenter;
    this.deltaX = (float) (40.0 * Math.random() - 20.0);

    this.y = yCenter;
    this.origY = yCenter;
    this.deltaY = (float) (40.0 * Math.random() - 20.0);

    this.origRadius = radius;
    this.radius = radius;
    this.deltaRadius = 0.5f * radius;

    this.color = color;
    this.alpha = 0;

    this.steps = steps;
}

void tick() {
    this.currentStep++;

    float fraction = (float) this.currentStep / (float) this.steps;

    this.radius = this.origRadius + fraction * this.deltaRadius;
    this.x = this.origX + fraction * this.deltaX;
    this.y = this.origY + fraction * this.deltaY;

    if (fraction <= 0.25f) {
        this.alpha = (int) (128 * 4.0f * fraction);
    } else {
        this.alpha = (int) (-128 * (fraction - 1) / 0.75f);
    }
}

boolean isDone() {
    return this.currentStep > this.steps;
}
}

提前致谢

4

1 回答 1

2

MathWorld 有一个很棒的心形函数；http://mathworld.wolfram.com/HeartCurve.html

基本上你必须在你的代码中做这样的事情；

float fraction = (float) this.currentStep / (float) this.steps;

-->

float t = this.currentStep * 2.0 * Math.PI / (float) this.steps;

this.x = 16.0 * Math.pow(Math.sin(t), 3.0));
this.y = 13.0 * Math.cos(t) - 5.0 * Math.cos(2.0 * t) -
          2.0 * Math.cos(3.0 * t) - Math.cos(4.0 * t);

希望对你有帮助，我是瞎写的，如有错误请多多包涵。对于半径，您可能想做这样的事情；

this.x *= radius / 16.0;
this.y *= radius / 16.0;
于 2013-01-14T19:04:12.283 回答