public PointOnPath AdvancePoint(PointOnPath pt, ref double dist)
{
// assert that we're looking at the same segment
Debug.Assert(Equals(pt.segment));
if (pt.dist + dist <= 0)
{
// handle the case of negative distance going before start point
dist += pt.dist;
return(StartPoint);
}
else if (pt.dist + dist >= cb.ArcLength)
{
// handle the case of positive distance going after end point
dist -= cb.ArcLength - pt.dist;
return(EndPoint);
}
else
{
// we're in the range that we can achieve
double targetDist = pt.dist + dist;
double tValue = cb.FindT(targetDist);
double actDist = cb.PartialArcLength(tValue);
dist = 0;
return(new PointOnPath(this, targetDist, cb.Bt(tValue)));
}
}
public static void DrawBezier(GLPen pen, PointF startP, PointF ctrl1, PointF ctrl2, PointF endP)
{
CubicBezier cb = new CubicBezier(Utility.ToCoord(startP), Utility.ToCoord(ctrl1), Utility.ToCoord(ctrl2), Utility.ToCoord(endP));
pen.GLApplyPen();
Gl.glBegin(Gl.GL_LINE_STRIP);
//iterate this bitch
for (double i = 0; i < 1.0; i += .025)
{
PointF p = Utility.ToPointF(cb.Bt(i));
Gl.glVertex2f(p.X, p.Y);
}
PointF p1 = Utility.ToPointF(cb.Bt(1));
Gl.glVertex2f(p1.X, p1.Y);
Gl.glEnd();
}
public void DrawBezier(IPen pen, PointF pt1, PointF pt2, PointF pt3, PointF pt4)
{
CubicBezier cb = new CubicBezier(Utility.ToCoord(pt1), Utility.ToCoord(pt2), Utility.ToCoord(pt3), Utility.ToCoord(pt4));
ApplyPen(pen);
Gl.glBegin(Gl.GL_LINE_STRIP);
//iterate this bitch
for (double i = 0; i < 1.0; i += .025)
{
PointF p = Utility.ToPointF(cb.Bt(i));
Gl.glVertex2f(p.X, p.Y);
}
PointF p1 = Utility.ToPointF(cb.Bt(1));
Gl.glVertex2f(p1.X, p1.Y);
Gl.glEnd();
}