add docs

README.md

@@ -404,6 +404,9 @@ These examples incubate dotSCAD and dotSCAD refactors these examples. See [examp
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 [**pp/pp_disk**(radius, value_count[, seed])](https://openhome.cc/eGossip/OpenSCAD/lib3x-pp_disk.html) | generate random points over a disk.
 [**pp/pp_sphere**(radius, value_count[, seed])](https://openhome.cc/eGossip/OpenSCAD/lib3x-pp_sphere.html) | pick random points on the surface of a sphere.
+[**pp/pp_poisson2**(size, r[, start, k, seed])](https://openhome.cc/eGossip/OpenSCAD/lib3x-pp_poisson2.html) | perform poisson sampling over a rectangle area.
+
+[**pp/pp_poisson3**(size, r[, start, k, seed])](https://openhome.cc/eGossip/OpenSCAD/lib3x-pp_poisson3.html) | perform poisson sampling over a cube space.
 
 ## Maze
 

docs/lib3x-pp_poisson2.md

@@ -0,0 +1,26 @@
+# pp_poisson2
+
+Perform poisson sampling over a rectangle area. An implementation of [Fast Poisson Disk Sampling in Arbitrary Dimensions](https://www.cs.ubc.ca/~rbridson/docs/bridson-siggraph07-poissondisk.pdf).
+
+**Since:** 3.3
+
+## Parameters
+
+- `size` : The size `[x, y]` of the rectangle.
+- `r` : The minimum distance between samples.
+- `start` : Optional. The first start point. 
+- `k` : Default to 30. The `k` constant of [Fast Poisson Disk Sampling in Arbitrary Dimensions](https://www.cs.ubc.ca/~rbridson/docs/bridson-siggraph07-poissondisk.pdf).
+- `seed` : Optional. Seed value for random number generator for repeatable results. 
+
+## Examples
+
+    use <pp/pp_poisson2.scad>
+    use <polyline_join.scad>
+
+    points = pp_poisson2([100, 100], 5);
+    for(p = points) {
+        translate(p)
+            circle(1);
+    }
+
+![pp_poisson2](images/lib3x-pp_poisson2-1.JPG)

docs/lib3x-pp_poisson3.md

@@ -0,0 +1,26 @@
+# pp_poisson3
+
+Perform poisson sampling over a cube space. An 3D implementation of [Fast Poisson Disk Sampling in Arbitrary Dimensions](https://www.cs.ubc.ca/~rbridson/docs/bridson-siggraph07-poissondisk.pdf).
+
+**Since:** 3.3
+
+## Parameters
+
+- `size` : The size `[x, y]` of the rectangle.
+- `r` : The minimum distance between samples.
+- `start` : Optional. The first start point. 
+- `k` : Default to 30. The `k` constant of [Fast Poisson Disk Sampling in Arbitrary Dimensions](https://www.cs.ubc.ca/~rbridson/docs/bridson-siggraph07-poissondisk.pdf).
+- `seed` : Optional. Seed value for random number generator for repeatable results. 
+
+## Examples
+
+    use <pp/pp_poisson3.scad>
+    use <polyline_join.scad>
+
+    points = pp_poisson3([50, 50, 50], 10);
+    for(p = points) {
+        translate(p)
+            sphere(5, $fn = 48);
+    }
+
+![pp_poisson3](images/lib3x-pp_poisson3-1.JPG)