processing - 在椭圆路径中旋转一些元素

Question

我正在尝试制作一些对象，比如 12，在 Processing 中以椭圆路径连续旋转。我有一个以圆形旋转的草图，我想让它以椭圆形旋转。我有一些来自处理论坛的指针，但指针中的代码与我发布的代码不同，我还无法理解(三角学弱)。

我用谷歌搜索了一下，发现了一篇试图用这个算法实现这一目标的帖子:

You need to define your ellipse with a few parameters:

x, y: center of the ellipse
a, b: semimajor and semiminor axes

If you want to move on the elipses this means that you change the angle between the major axes and your position on the ellipse. Lets call this angle alpha.

Your position (X,Y) is:

X = x + (a * Math.cos(alpha));
Y = y + (b * Math.sin(alpha));

In order to move left or right you need to increase/decrease alpha and then recalculate your position. Source: http://answers.unity3d.com/questions/27620/move-object-allong-an-ellipsoid-path.html

我如何将它集成到我的草图中？谢谢你。

这是我的草图:

void setup()
{
    size(1024, 768);
    textFont(createFont("Arial", 30));
}

void draw()
{
    background(0);
    stroke(255);

    int cx = 500;
    int cy = 350;
    int r = 300; //radius of the circle
    float t = millis()/4000.0f; //increase to slow down the movement

    ellipse(cx, cy, 5, 5);

    for (int i = 1 ; i <= 12; i++) {
        t = t + 100;
        int x = (int)(cx + r * cos(t));
        int y = (int)(cy + r * sin(t));

        line(cx, cy, x, y);
        textSize(30);
        text(i, x, y);

        if (i == 10) {
            textSize(15);
            text("x: " + x + " y: " + y, x - 50, y - 20);
        }
    }
}

Answer 1

代替

int r = 300; //radius of the circle

和

int a = 350; // major axis of ellipse
int b = 250; // minor axis of ellipse

并替换

int x = (int)(cx + r * cos(t));
int y = (int)(cy + r * sin(t));

和

int x = (int)(cx + a * cos(t));
int y = (int)(cy + b * sin(t));