A bunch of geometic shapes, desaturated and with opacity reduced.
Attachment:
faded-triangles.jpg [ 72.15 KiB | Viewed 2221 times ]
Triangles (and other shapes) can be generated using the standard Gimp filter Distorts -> Mosaic
Because of the limitations of the GUI these are small when applied to a large canvas.
One way round this is apply the mosaic plugin directly using the python terminal. That allows larger size values.
video demo: 2.5 minutes
https://youtu.be/zWTii9hb6v4Attached my crib sheet with the necessary commands. (remember to unzip it)