How to Create a new World Map

From Vindkast:

map.dat is 262144 bytes— one for each square on the map (512 by 512)

each byte is (hex) 00, 01, or 02, representing ground, lava, rocks respectively

you can recreate the format using 3 colors in an 8-bit, 512px x 512px BMP

in saaay photoshop, an easy way to do it would be:
- make a map using any 3 colors
- go Image → Mode → Indexed Color
- go to Save As, pick BMP
- select Windows, 8-bit, FLIP ROW ORDER
- save
- switch colors around if 00,01,02 don’t match ground,lava,rock
- remove ~800 byte BMP header/footer
- place in pie dish
- serve