public static Point GetLineCross(this LineObj l0, LineObj l1)
{
double u;
// do both lines exhist?
if (l0 == null && l1 == null)
{
return(null);
}
// are both lines vertical?
if (double.IsNaN(l0.c) && double.IsNaN(l1.c))
{
// no intersection; is parallel, not vertical
if (l0.a.Equals(l1.a))
{
return(null);
}
// common X value
u = (l1.b - l0.b) / (l0.a - l1.a);
return(new Point(u, l0.a * u + l0.b));
}
// l0.c != undefined
// wasn't fun figuring this out
// should write some notes on this Object usage.
if (!double.IsNaN(l0.c))
{
if (!double.IsNaN(l1.c))
{
// both lines vertical, intersection does not exhist
return(null);
}
else
{
// return the point on l1 with x = l0.c
return(new Point(l0.c, (l1.a * l0.c + l1.b)));
}
}
else if (!double.IsNaN(l1.c))
{
// l0.c as it was tested above
// return the point on l0 with x = l1.c
return(new Point(l1.c, (l0.a * l1.c + l0.b)));
}
return(null);
}
public static Point GetLineCross(this LineObj l0, LineObj l1)
{
double u;
// do both lines exhist?
if (l0==null && l1==null) return null;
// are both lines vertical?
if (double.IsNaN(l0.c) && double.IsNaN(l1.c))
{
// no intersection; is parallel, not vertical
if (l0.a.Equals(l1.a)) return null;
// common X value
u = (l1.b - l0.b) / (l0.a - l1.a);
return new Point(u, l0.a * u + l0.b);
}
// l0.c != undefined
// wasn't fun figuring this out
// should write some notes on this Object usage.
if (!double.IsNaN(l0.c)) {
if (!double.IsNaN(l1.c)) {
// both lines vertical, intersection does not exhist
return null;
}
else
{
// return the point on l1 with x = l0.c
return new Point(l0.c, (l1.a * l0.c + l1.b));
}
}
else if (!double.IsNaN(l1.c)) {
// l0.c as it was tested above
// return the point on l0 with x = l1.c
return new Point(l1.c, (l0.a * l1.c + l0.b));
}
return null;
}
int DrawCubicBézier(IApiDraw api, Vertex pt)
{
Tuple <Point, LineObj> curt = null; // Tangent Object (LineObj)?
Tuple <Point, LineObj> next; // Tangent Object (LineObj)?
int total = 0; // int or long
int nSegment = numSegments < 2 ? 4 : this.numSegments;
double tstep = 1 / nSegment;
curt = new Tuple <Point, LineObj>(pt.p0, LineObj.GetLine(pt.p0, pt.p1));
if (api != null)
{
api.moveTo(pt.p0);
}
for (int i = 1; i < nSegment; i++)
{
next = pt.CubicTangent(Convert.ToInt32(i * tstep)); // next tangent
total += SliceCubicBézierSegments(api, pt, (i - 1) * tstep, i * tstep, curt, next, 0); // current segment
if (total > numSegments)
{
}
curt = next;
}
return(total);
}
