Algorithm 2:

Fast Variable Density Poisson-Disc Sampling

Inputs: rmin, background array, parameter k

Select a point at random, add it to the list of points, add index 1 to the active list, and set N = 1

While: active list is not empty

Randomly select index i from the active list

Identify the poisson-disc parameter for this point, r(xi)

Create k new points uniformly at random in the spherical annulus between radii r(xi) and 2r(xi) centered on xi

For each: created point yj

If yj is not within domain bounds, continue

Compute the distance to those points with indices in the list of the background grid element that contains yj.

If the minimum computed distance > r(yj)

Add yj to the list of points, add index N + 1 to the active list and the lists of the background grid elements with points that may be within r(yj) according to Fig. 1b, and then increment N by 1.

End If

End For

If none of the k points were valid, remove i from the active list.

End While

Outputs: List of points