@rek Ok, thanks. I agree about the reuse, unfortunately my 3D MMO uses the final OpenGL feature for animation: skin mesh skeletal with VAO that came with 3+, that is not present on my old Thinkpad X61s. So I need something newer, the Pi 4 is my lower requirement. Now I'm thinking I could use some portable display with this keyboard I made last week: http://move.rupy.se/file/last_computer.png