public static SpiroSegment[] setup_path(SpiroControlPoint[] src, int n)
{
int i, ilast, n_seg;
double dx, dy;
SpiroSegment[] r;
#if CHECK_INPUT_FINITENESS
// Verify that input values are within realistic limits
for (i = 0; i < n; i++)
{
if (IsFinite(src[i].X) == 0 || IsFinite(src[i].Y) == 0)
{
return null;
}
}
#endif
n_seg = src[0].Type == SpiroPointType.OpenContour ? n - 1 : n;
r = new SpiroSegment[n_seg + 1];
for (int j = 0; j < n_seg + 1; j++)
r[j].ks = new double[4];
if (r == null)
return null;
for (i = 0; i < n_seg; i++)
{
r[i].X = src[i].X;
r[i].Y = src[i].Y;
r[i].Type = src[i].Type;
r[i].ks[0] = 0.0;
r[i].ks[1] = 0.0;
r[i].ks[2] = 0.0;
r[i].ks[3] = 0.0;
}
r[n_seg].X = src[n_seg % n].X;
r[n_seg].Y = src[n_seg % n].Y;
r[n_seg].Type = src[n_seg % n].Type;
for (i = 0; i < n_seg; i++)
{
dx = r[i + 1].X - r[i].X;
dy = r[i + 1].Y - r[i].Y;
#if !CHECK_INPUT_FINITENESS
r[i].seg_ch = hypot(dx, dy);
#else
if (IsFinite(dx) == 0 || IsFinite(dy) == 0 || IsFinite((r[i].seg_ch = hypot(dx, dy))) == 0)
{
return null;
}
#endif
r[i].seg_th = Math.Atan2(dy, dx);
}
ilast = n_seg - 1;
for (i = 0; i < n_seg; i++)
{
if (r[i].Type == SpiroPointType.OpenContour || r[i].Type == SpiroPointType.EndOpenContour || r[i].Type == SpiroPointType.Corner)
r[i].bend_th = 0.0;
else
r[i].bend_th = mod_2pi(r[i].seg_th - r[ilast].seg_th);
ilast = i;
}
return r;
}
public static SpiroSegment[] run_spiro(SpiroControlPoint[] src, int n)
{
int converged, nseg;
SpiroSegment[] s;
if (src == null || n <= 0)
return null;
s = setup_path(src, n);
if (s != null)
{
nseg = src[0].Type == SpiroPointType.OpenContour ? n - 1 : n;
converged = 1; // this value is for when nseg == 1; else actual value determined below
if (nseg > 1)
converged = solve_spiro(s, nseg);
if (converged != 0)
return s;
}
return null;
}
