尝试使用正弦和余弦制作星星

Question

所以我想为我要画一面旗帜的节目做一个明星。我几乎只局限于 Java Applet class。由于每个具有不同中心的恒星的过程应该相同，我想我会将中心传递给具有 X 和 Y 值的方法，然后使用多边形根据与中心的角度绘制它。问题是出现的形状绝不是星星。

public void paint( Graphics g)
{
    super.paint( g );
    Polygon star= new Polygon();
    int radius=20;
    int roundX=(int)Math.round(radius*Math.cos(Math.toRadians(54)));
    int roundY=(int)Math.round(radius*Math.sin(Math.toRadians(54)));
    int originX=100,originY=100;
    //int radius=20;
    int topY=originY+radius;
    int bottomLeftX=originX+roundX;
    int bottomY=originY-roundY;
    int middleY=originY+(int)Math.round(radius*Math.sin(Math.toRadians(18)));;
    int midRightX=originX+(int)Math.round(radius*Math.cos(Math.toRadians(18)));;
    int midLeftX=originX-(int)Math.round(radius*Math.cos(Math.toRadians(18)));
    int bottomRightX=originX+roundX;
    int bottomRightY=middleY-roundY;
    star.addPoint(originX, originY);
    star.addPoint(originX, topY);
    star.addPoint(bottomLeftX, bottomY);
    star.addPoint(midRightX, middleY);
    //star.addPoint(midLeftX, middleY);
    //star.addPoint(bottomRightX, bottomY);
    //star.addPoint(originX, topY);
    g.drawPolygon(star);
}

因此左下角的点应与中心成 234 度角或与 x 轴成 54 度角。当我对其中任何一个进行编码并更改操作（+ 或减号）时，它似乎朝着与我预期相反的方向射击。中间点应该在中心上方 18 度，尽管从外观上看它们几乎与 x 轴对齐。我一直在一个一个地禁用点，看看我是否可以调整它以更接近一颗星星，但此时我意识到这相当于在蒙着眼睛和醉酒时雕刻。

如果你能帮我找出问题所在，我将不胜感激。

Answer 1

也许你想要一个五角星。

private double sin(int degree) {
    return Math.sin(Math.toRadians(degree));
}

private double cos(int degree) {
    return Math.cos(Math.toRadians(degree));
}

@Override
public void paint(Graphics g) {
    super.paint(g);
    Polygon star = new Polygon();

    int radius = 20;
    int originX = 100;
    int originY = 100;
    int innerRadius = (int) Math.round(radius * sin(18) / sin(126));

    Point[] points = new Point[11];
    // top center 
    points[0] = new Point();
    points[0].x = 0;
    points[0].y = -radius;
    // inner top left
    points[1] = new Point();
    points[1].x = -(int) Math.round(innerRadius * cos(54));
    points[1].y = -(int) Math.round(innerRadius * sin(54));
    // top left 
    points[2] = new Point();
    points[2].x = -(int) Math.round(radius * cos(18));
    points[2].y = -(int) Math.round(radius * sin(18));
    // inner bottom left
    points[3] = new Point();
    points[3].x = -(int) Math.round(innerRadius * cos(18));
    points[3].y = (int) Math.round(innerRadius * sin(18));
    // bottom left
    points[4] = new Point();
    points[4].x = -(int) Math.round(radius * cos(54));
    points[4].y = (int) Math.round(radius * sin(54));
    // inner bottom center
    points[5] = new Point();
    points[5].x = 0;
    points[5].y = innerRadius;
    // bottom right
    points[6] = new Point();
    points[6].x = (int) Math.round(radius * cos(54));
    points[6].y = (int) Math.round(radius * sin(54));
    // inner bottom right
    points[7] = new Point();
    points[7].x = (int) Math.round(innerRadius * cos(18));
    points[7].y = (int) Math.round(innerRadius * sin(18));
    // top right
    points[8] = new Point();
    points[8].x = (int) Math.round(radius * cos(18));
    points[8].y = -(int) Math.round(radius * sin(18));
    // inner top right
    points[9] = new Point();
    points[9].x = (int) Math.round(innerRadius * cos(54));
    points[9].y = -(int) Math.round(innerRadius * sin(54));
    // top center
    points[10] = new Point();
    points[10].x = 0;
    points[10].y = -radius;

    for (int i = 0; i < points.length; i++) {
        star.addPoint(originX + points[i].x, originY + points[i].y);
    }
    g.drawPolygon(star);

}

尝试使用正弦和余弦制作星星

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