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README.md

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+# Pattern filling with OpenSCAD
+
+This OpenSCAD module provides the required mechanisms to spray a pattern on a
+surface.
+
+## Possible usages
+
+Patterns are widely used in common objects, and so are the possible usages of
+this module:
+ - [alveolar reinforcement](examples/reinforcement/)
+ - moucharabieh
+ - decorative patterns
+ - surface texturing
+
+## Examples
+
+In the [examples](examples) folder, common examples are provided to illustrate
+what can be achieved and how to use this module.
+
+## How to use it
+
+First, you will need to get a copy of this module locally:
+```
+git clone https://github.com/nmasse-itix/OpenSCAD-Pattern-Filling.git
+```
+
+In your OpenSCAD file, include this module:
+```
+use <OpenSCAD-Pattern-Filling/pattern.scad>
+```
+
+Then, build your base shape (in this example, an octogon and a square):
+```
+module mypattern(r) {
+  // The octogon
+  rotate([0,0,22.5])
+    circle(r=r, center=true, $fn=8);
+
+  // The square
+  l = 2 * r * sin(22.5);
+  translate([r,r,0])
+    rotate([0,0,45])
+      square([l,l], center=true);
+}
+```
+
+Instanciate it once in order to check it matches your expectations:
+```
+r = 2;
+mypattern(r);
+```
+
+![our base shape](documentation/images/tutorial_base_shape.png?raw=true)
+
+Then, you need to define two things:
+ - a bounding box (the area to spray)
+ - the two moves defining how to spray our pattern
+
+```
+bounding_box = [
+  [0,0],     // Lower left corner
+  [20, 20]   // upper right corner
+];
+moves = [
+  [ 2*r, 0], // For the first move, we will translate on x by two times the radius
+  [ 0, 2*r], // For the second move, we will translate on y by two times the radius
+];
+```
+
+Finally, the pattern can be sprayed:
+```
+spray_pattern(bounding_box, moves)
+  mypattern(r);
+```
+
+![the sprayed pattern](documentation/images/tutorial_sprayed_pattern.png?raw=true)
+
+If you like clean edges, you can cut the sprayed pattern at bounding box size
+by intersecting the pattern with the bounding box:
+```
+intersection() {
+  spray_pattern(bounding_box, moves)
+    mypattern(r);
+  square(bounding_box[1] - bounding_box[0]);
+}
+```
+
+![a clean cut of our pattern](documentation/images/tutorial_clean_cut.png?raw=true)
+
+Check [the complete source code](examples/tutorial.scad) for more information.
+
+## Limitations
+
+Currently, the first move needs to be exclusively on the x axis otherwise
+the pattern may not be sprayed correctly, leaving blank area.