These tools will help you understand, unpack and edit Stunt GP files
Original thread: https://forum.xentax.com/viewtopic.php?f=16&t=16944&p=160266#p160266
Check out the wiki for more information about the game and its file formats.
go build cmd/pc_pack/pc_pack.go
go build cmd/pc_unpack/pc_unpack.go
Or grab compiled .exe here
You can also drag and drop multiple files on pc_pack or pc_unpack
./pc_pack mini.png
./pc_pack mini.png -o output.pc
# pack Dreamcast texture
./pc_pack mini.png --dc
./pc_pack mini.png -o output.dc --dc
# unpack texture (including Dreamcast)
./pc_unpack mini.pc
./pc_unpack mini.pc -o output.png