我正在为L-Systems创建一个Android应用程序,并且在旋转矩阵后得到不同的行长度,这会导致不规则的分形。为什么我在Android中使用矩阵旋转点时会得到不同的行长度,我该如何解决?
实施例:
正如你可以看到,旋转线的长度而变化,以120°的旋转的线比为240°的旋转的线短。
。
对于旋转,我使用这些Android Matrix Operations基于this answer here点。 我正在围绕它的起点旋转一条线的终点。
代码:
Matrix transform;
public Point rotate(Point angleP, Point p, float degrees) {
// This rotates around the previous Point by degrees
transform.setRotate(degrees, angleP.x, angleP.y);
// Create new float[] to hold the rotated coordinates
float[] pts = new float[2];
// Initialize the array with our Coordinate
pts[0] = p.x;
pts[1] = p.y;
// Use the Matrix to map the points
transform.mapPoints(pts);
// NOTE: pts will be changed by transform.mapPoints call
// after the call, pts will hold the new cooridnates
// Now, create a new Point from our new coordinates
Point newPoint = new Point((int)pts[0], (int)pts[1]);
// Return the new point
return newPoint;
}
的对应点+旋转前五个点基于上述代码:
- forward by 30pt, angle is: 0.0°, rotate/translate Point(384, 433) -> Point(384, 433)
- changed rotation by120.0 from 0.0->120.0
- forward by 30pt, angle is: 120.0°, rotate/translate Point(384, 403) -> Point(409, 447)
- changed rotation by-120.0 from 120.0->0.0
- forward by 30pt, angle is: 0.0°, rotate/translate Point(409, 417) -> Point(409, 417)
- changed rotation by-120.0 from 0.0->-120.0
- forward by 30pt, angle is: -120.0°, rotate/translate Point(409, 387) -> Point(383, 431)
- changed rotation by120.0 from -120.0->0.0
- forward by 30pt, angle is: 0.0°, rotate/translate Point(383, 401) -> Point(383, 401)
调试 - 日志中的前五个线(最多 - >右 - >向上 - >左 - >向上,相同的图片):
line# line-start line-end line-length
line0 from 384/463 to 384/433, length: 30.0
line1 from 384/433 to 409/447, length: 28.653097563788805
line2 from 409/447 to 409/417, length: 30.0
line3 from 409/417 to 383/431, length: 29.5296461204668
line4 from 383/431 to 383/401, length: 30.0
有问题IM是,我想/需要的RESU使线条长度相等,但由于某些原因,旋转120°的线比旋转-120°的线要小。
我的猜测是,不同的线路长度舍入误差的结果,但我不知道我怎么会开始修复这一点。
任何帮助或指针,将不胜感激。