Very good idea Suyono,
Thank you
Donald
I plan to make another small program: "Ground-Replacer.exe". It works
like this. Assume that you have a GBMP.bmp (game bitmap file, 320x192
pixels) and a new ground tile (32x32 pixels); the program will replace
all the ground in GBMP.bmp with the new ground as long as there is no
color conflict. (It's a boring process if you do it manually.) This
program is also useful if you want to separate objects from the ground
it's sitting on. (E.g., you create a dummy monochrome pink ground. The
program will make objects on the pink ground.)