public MyLine3D(MyPoint from, MyPoint to, bool ispa)
{
fromNode = from;
toNode = to;
isParallel = ispa;
}
public MyLine3D(float x1, float y1, float z1, float x2, float y2, float z2, bool ispa)
{
fromNode = new MyPoint(x1, y1, z1);
toNode = new MyPoint(x2, y2, z2);
isParallel = ispa;
}
public PointF projectionPerspective(MyPoint viewPoint)
{
return(new PointF(viewPoint.X + (X - viewPoint.X) * viewPoint.Z / (viewPoint.Z - Z), viewPoint.Y + (Y - viewPoint.Y) * viewPoint.Z / (viewPoint.Z - Z)));
}
public PointF projectionParallel(MyPoint direction)
{
return(new PointF(X - Z * direction.X / direction.Z, Y - Z * direction.Y / direction.Z));
}
public PointF projectionPerspective(MyPoint poi)
{
return(new PointF(viewPoint.X + (poi.X - viewPoint.X) * viewPoint.Z / (viewPoint.Z - poi.Z), viewPoint.Y + (poi.Y - viewPoint.Y) * viewPoint.Z / (viewPoint.Z - poi.Z)));
}
public PointF projectionParallel(MyPoint poi)
{
return(new PointF(poi.X - poi.Z * viewPoint.X / viewPoint.Z, poi.Y - poi.Z * viewPoint.Y / viewPoint.Z));
}
private void pictureBoxDown_Paint(object sender, PaintEventArgs e)
{
/* ********************************
* 绘制坐标系
* 主要绘制的是坐标轴
* ***********************/
Graphics g = e.Graphics;
Pen pen = new Pen(Color.Black);
int width = pictureBoxDown.Width, height = pictureBoxDown.Height;
Point pO = new Point(width / 2 - 10, height / 2 + 2);
Point pX = new Point(width - 10, height / 2 + 2);
Point pY = new Point(width / 2 + 1, 0);
Font f = new Font("Arial", 8);
g.DrawString("O", f, Brushes.Black, pO);
g.DrawString("X", f, Brushes.Black, pX);
g.DrawString("Y", f, Brushes.Black, pY);
g.DrawLine(pen, width / 2, 0, width / 2, height / 2);
g.DrawLine(pen, width / 2, 0, width / 2 - 2, 5);
g.DrawLine(pen, width / 2, 0, width / 2 + 2, 5);
g.DrawLine(pen, width / 2, height / 2, width, height / 2);
g.DrawLine(pen, width - 5, height / 2 - 2, width, height / 2);
g.DrawLine(pen, width - 5, height / 2 + 2, width, height / 2);
//接下来是画 z 轴
//投影 z 轴上足够远得一点
PointF pZ;
if (isParallel)
{
//pZ = new MyPoint(0, 0, 50000).projectionParallel(station);
pZ = new MyPoint(0, 0, station.Z / 2).projectionParallel(station);
pZ = getEnd(new PointF(0, 0), pZ, 5000);
}
else
{
pZ = new MyPoint(0, 0, station.Z / 2).projectionPerspective(station);
pZ = getEnd(new PointF(0, 0), pZ, 5000);
}
if (pZ.X >= width / 2 - 20)
{
pZ = new PointF(width / 2 - 20, pZ.Y * (width / 2 - 20) / pZ.X);
}
else if (pZ.X <= -width / 2 + 10)
{
pZ = new PointF(-width / 2 + 20, pZ.Y * (-width / 2 + 20) / pZ.X);
}
if (pZ.Y >= height / 2 - 20)
{
pZ = new PointF(pZ.X * (height / 2 - 20) / pZ.Y, height / 2 - 20);
}
else if (pZ.Y <= -height / 2 + 20)
{
pZ = new PointF(pZ.X * (-height / 2 + 20) / pZ.Y, -height / 2 + 20);
}
//将 pZ 变换到显示坐标系中去
g.DrawLine(pen, width / 2, height / 2, pZ.X + width / 2, -pZ.Y + height / 2);
if (pZ.X == 0 && pZ.Y == 0)
{
g.FillEllipse(Brushes.Red, width / 2 - 1, height / 2 - 1, 2, 2);
g.DrawString("Z", f, Brushes.Black, pZ.X + width / 2, pZ.Y + height / 2);
}
else
{
PointF end = getEnd(pZ, Math.Atan2(pZ.Y, pZ.X) - 0.4 + Math.PI, 8);
g.DrawLine(pen, pZ.X + width / 2, -pZ.Y + height / 2, end.X + width / 2, -end.Y + height / 2);
end = getEnd(pZ, Math.Atan2(pZ.Y, pZ.X) + 0.4 + Math.PI, 8);
g.DrawLine(pen, pZ.X + width / 2, -pZ.Y + height / 2, end.X + width / 2, -end.Y + height / 2);
end = getEnd(pZ, Math.Atan2(pZ.Y, pZ.X), 8);
g.DrawString("Z", f, Brushes.Black, end.X + width / 2, -end.Y + height / 2);
}
}