操作脚本 3 - 2D 介绍如何将图形包裹在圆柱体周围

Question

我有在 3D 空间中旋转的绘图（具有 x 和 y 坐标的点数组）：http://www.motiondraw.com/md/as_samples/Testing/_mindreader/main.html

就像现在一样，这幅画看起来就像包裹在一个立方体上，角落里有一个令人讨厌的 90° 度。相反，它应该看起来像是包裹在圆柱体上。在开始旋转之前，我调用一个函数（在ActionScript中）"bendDrawing"，为每个点设置一个初始z值：

for （var j = 0; j <numPoints;> 图形居中 – 中心左侧的点<0 var distFromCenter = Math.abs（shape[i].points[j].x）;

var wid = 350;// this could be the radius of the cylinder
// NOTE: suboptimal, as the image gets a 90° corner in the center, at its highest point
// what it should look like: as if the image was wrapped around a cylinder, i.e. in a circular shape
// is that pythagoras? draw triangle, calc distance from base, add to this to c?
var z = wid - distFromCenter;
shape[i].points[j].z =  Math.abs( z);

}

我只是无法解决这个问题;-）任何指示都非常感谢！

安德烈亚斯·韦伯

Answer 1

试试这个：

shape[i].points[j].z  = 
    wid * Math.cos((shape[i].points[j].x / wid) * (0.5 * Math.PI));