OK I’ve tried on PiCrate with processing4, works fine, the same sketch on my very pared down raspberryPI3B+, runs for quite a few frames and then crashes (I’ve tried with 64MB, 128MB and 264MB GPU memory and it makes no difference). My RaspberryPI4 has 4GB Ram with a default 64GB GPU Ram, suggesting perhaps RaspberryPI3B+ with RaspberryPI OS does not have enough muscle? PS contrary to stuff posted on processing RasbberryPI website you should use full KMS mode, and ignore original driver (at least since buster).