# Demystifying Sevilla’s Parasols: Waffle Structures

Free Tutorials

At a recent Houdini meetup, Luc Morroni came up with quite an interesting tutorial topic: Procedural waffle structures, like the ones used in Sevilla’s Metropol Parasol.

Seems easy enough at first I thought – but as always, the devil’s in the details. In this case in the cutouts where the parts slot into each other. So enjoy hearing me waffle on (see what I did there?) about creating those types of structures and making them intersect realistically(ish).

1. Paul

Nice little tutorial again! Helps me learn so much. Thank you.
Little idea for a small addition to the tutorial. Maybe you could show us how you might nest the components out to a flat sheet so that you could then cnc or laser cut these componets.

• Stefan

You can add another connectivity for-loop at the output.
Inside the loop add a UV-projection per piece (for translation, enter the centroid-expression for every axis ( centroid(0, D_X) ), that way the project is always centered on each piece.
For rotation you need a 90 degree flip on the y-axis after you reach half the iterations.
After the loop add a uvlayout node to place all pieces inside the 0-1 UV range.
Then add a pointwrangle node and just transform the points by uvs with that simple line: @P = @uv;
That would layout all pieces in a square.

2. Stefan

Nice video, I am really a big fan of those experimental recreations. It’s quite fun to find solutions to recreate patterns, sometimes I just get lost in trying different methods for the same result.

One comment for the video:
You can spare the wrangle detail-expression in the forloop and just write this into the Y-axis: centroid(0, D_Y)
That gives you directly the centerpoint in Y-axis.