You could also check out James Bowman's "Gameduino" line of graphics boards [0:2] (which includes a Forth-programmable CPU, the J1 [3], implemented on FPGA)

[0] https://excamera.com/sphinx/gameduino/

[1] https://excamera.com/sphinx/gameduino2/

[2] https://excamera.com/sphinx/gameduino3/

[3] https://excamera.com/sphinx/fpga-j1.html