Stefan Hintz

“Revert to” in the Girih App

With the “Revert to“-feature in the Girih App you can easily browse all previously saved versions of your design and if needed revert to another version.
You will find this function in the menu via: File -> Revert to -> Browse All Versions…

You can even share and old design without reverting it.

“Revert to” in the Girih App

Cube Ring 36

Cube Rings 36
This image was created with the Girh App.

Girih App

To create even easier ornaments, than with the laser cutted Girih tiles, I decided to write a specialized App for it.

An App has some advantages to the physical tiles:

Physical tiles tend to move around a bit, when you release your fingers or add another piece.

Loose tiles can not be durable stored as ornament.

The number of physical tiles is limited.

The look and size of physical tiles is fixed.

You can not seamless join physical tiles.

Download the Girih App Version 1.5 from June 2017.

Requirements: OS X 10.11 El Capitan

Girih App by Stefan Hintz

This App is completely written in Swift.

As an addition to the standard Girih shapes: Decagon, Pentagon, Hexagon, Bow Tie and Rhombus at added some more shapes.

Not all of the shapes can be combined together without gaps.

So this App is also useful for creating Penrose Patterns or Ornaments from regular Polygons.

I am curious to see, what you create with it. If you tweet about it, tag it with: #Girih

Please let me know what you like about my Girih App and what not.


Pattern created with the Girih App

Laser Cutting Girih Tiles

Years after the idea of laser cutting Girih Tiles I attended a laser cutter workshop.

I decided to build upon an existing file rather than using my own old SketchUp files, because of two features:

Engraving and the ‘Teeth’ pattern on the sides.

You can find the file for laser cutting girih tiles in the blog of Johanna Grönqvist.

I had problems to use this file with the software, that came with the laser cutter. Most tiles where absolute correct, but a few did not have the engraving filled. I tried exporting different file formats including PDF, EPS and DXF. With DXF nothing was filled.
The next try was not using that laser software, that could not read PDF correctly. Instead I used just the Windows printer driver to access the laser cutter from the Adobe Acrobat Reader, with can certainly read PDF files correctly. The preview in the print dialog looked OK, but the first output was a big failure. The output had a wrong aspect ratio and wrong scale. So the result was completely unusable.

For the second try I only changed the dimensions of the PDF to the working area of the laser cutter (600 mm x 300 mm), without rescaling the content of the drawing.

And that finally worked well.

Laser1 Laser2 Laser3 Laser4 Laser5 Laser6

Girih Tiles

In 2012, while I was designing my LED installations at home, I started about placing the LEDs in circles in circular arcs.

At that time I had a flexible five meter long LED strip with individually addressable LEDs. (WS2801)
So I came up with five fold symmetries. Later I replaced the circles by regular Decagons.

The shapes I was using where a subset of the Girih Tiles. I like the infinite possibilities to tile a plane without a gap with those tiles. And I also like that each tile has the same side length.

I used SketchUp for my designs. The construction of different variants ornaments with many tiles is quite tedious there. So I wanted to cut those tiles with a laser cutter from acrylic sheets.


3D Modelling

Today I attended a 3D Printing Workshop, where I had to design a 3D object with a for me totally unknown browser based software. After playing around with some shapes builded with polygonal pyramids I decided to start another design using a combination of rings.
I liked my creation so much, that I rebuilded it with a for me totally known text based software.
And this is the result:

3D object build from rings

Epic Fulffy-Duup

3D Print: