public void generateSample(int r, int t)
{
if (t > 1)
{
if (r == rank &&
t == total)
{
return;
}
int uCell, vCell;
if (t != total || r < rank) // [re-]initialization
{
total = t;
uCell = rnd.PermutationFirst(total, ref permU);
vCell = rnd.PermutationFirst(total, ref permV);
}
else
{
uCell = Math.Max(rnd.PermutationNext(ref permU), 0);
vCell = Math.Max(rnd.PermutationNext(ref permV), 0);
}
rank = r;
// point sample will be placed into [ uCell, vCell ] cell:
u = (uCell + rnd.UniformNumber()) / total;
v = (vCell + rnd.UniformNumber()) / total;
}
else
{
u = rnd.UniformNumber();
v = rnd.UniformNumber();
}
// TODO: do something like:
sample = source.position + u * source.width + v * source.height;
}