// 投影
private Point usingProject(thPoint pjtPoi)
{
int xp, yp;//viewtPoi:视点坐标或者平行投影的方向
try {
if (viewtPoi.Z == pjtPoi.Z)
{
pjtPoi.Z = pjtPoi.Z - 1;
}
//参考了课本58页的式子
if (projWay == 0) //透视投影
{
xp = Convert.ToInt32(viewtPoi.X + (pjtPoi.X - viewtPoi.X) * viewtPoi.Z / (viewtPoi.Z - pjtPoi.Z + 0.0));
yp = Convert.ToInt32(viewtPoi.Y + (pjtPoi.Y - viewtPoi.Y) * viewtPoi.Z / (viewtPoi.Z - pjtPoi.Z + 0.0));
//double xd = viewtPoi.X + (pjtPoi.X - viewtPoi.X) * viewtPoi.Z / (viewtPoi.Z- pjtPoi.Z + 0.0);//double yd = viewtPoi.Y+ (pjtPoi.Y - viewtPoi.Y) * viewtPoi.Z/ (viewtPoi.Z- pjtPoi.Z + 0.0);
return(new Point(xp, yp));
}
else if (projWay == 1) //平行投影
{
xp = Convert.ToInt32(pjtPoi.X - pjtPoi.Z * viewtPoi.X / (viewtPoi.Z + 0.0));
yp = Convert.ToInt32(pjtPoi.Y - pjtPoi.Z * viewtPoi.Y / (viewtPoi.Z + 0.0));
return(new Point(xp, yp));
}
else
{
MessageBox.Show("投影方式有错");
return(new Point(0, 0));
}
}catch (Exception ecp) {
MessageBox.Show(ecp.ToString());
return(new Point(0, 0));
}
}
//旋转；传入三维点，传出三维点 之后考虑float
private thPoint rotateOnce(thPoint iput) // rotate y
{
int alpha = stepLen; //参考课本52页 关于y轴旋转的式子
int outPox = Convert.ToInt32(iput.X * Math.Cos(alpha / 180.0 * Math.PI) + iput.Z * Math.Sin(alpha / 180.0 * Math.PI));
int outPoz = Convert.ToInt32(-iput.X * Math.Sin(alpha / 180.0 * Math.PI) + iput.Z * Math.Cos(alpha / 180.0 * Math.PI));
//将Math.Cos(alpha / 180.0 * Math.PI)用全局变量记录，在传入步长变化时再算可以减少计算量
//旋转部分可以由点进行迭代，有一定误差，也可以递增alpha，后者计算量更大，
return(new thPoint(outPox, iput.Y, outPoz));
}
//对点序列进行旋转，画出旋转后的边，并传出旋转后的点
private thPoint[] rotateDmrCub(thPoint[] dcLst)
{
thPoint[] rdcLst = new thPoint[8];
for (int i = 0; i < 8; i++)
{
rdcLst[i] = rotateOnce(dcLst[i]);
}
dimPlst = projOnebyOne(rdcLst);//降维后的点序列
return(rdcLst);
}
private void projZForm_Load(object sender, EventArgs e)
{
g = CreateGraphics();
Matrix mat = new Matrix(1, 0, 0, -1, 0, 0);//沿X轴翻转
g.Transform = mat;
g.TranslateTransform(300, -260);
//初始化一些默认值
viewtPoi = new thPoint(200, 200, 200);
deftPoi = new thPoint(20, 30, 40);
deftCube = new Cube(new thPoint(20, 30, 40), 80, 50, 40);
rtList = deftCube.PoiList;
}
