How can I edit .qvm (Quake Virtual Machine) files?

Question

I was browsing through how to mod a game (Urban Terror, a Quake 3 mod). I found that it can be done by editing .qvm files in the game. Under the file named zpak000.pk3. That file contains other files named

ui.qvm
qagame.qvm
cgame.qvm

But I can't find a way in which I can edit these files.

Answer 1

You create qvm files using the c-compiler in the Quake SDK.

You can't edit QVM files.

(You could technically modify them using a hex editor, in the same way that you can modify other compiled programs, but this is not useful for your purposes.)

Answer 2

Well, never heared about google :) ?

Look at game-deception it explains how to modificate a qvm (' after it has been compiled '). It just over-compile the certain lines / commands. The only problem ( for you ) is, that you have to work with opcodes ( / assembler ). Well, here's the tutorial made by the great macpunk : http://www.gamedeception.net/threads/19198-Runtime-QVM-Modification

vmHeader_t *hook_VM_LoadQVM( vm_t *vm, qboolean alloc )

{

vmHeader_t *ret = orig_VM_LoadQVM(vm, alloc);

if(!strcmp(vm->name, "cgame")

{

    vm->instructionPointers[0x0FF5E7] = 0x00; //0x00 is the opcode of whatever you want the instruction to be

}

return ret;
}

You need to Quake3 Engine SDK for the structs.

Answer 3

Edit them with a hex editor downloaded somewhere from the 'net.