the weapon model consists of several parts:
1. world model example: mp40.mdc, mp40_1.mdc mp40_2.mdc
2. vertical world model: pu_mp40.mdc
3. view model: v_mp40.mdc, v_mp40_barrel.mdc, v_mp40_barrel2.mdc, v_mp40_barrel3.mdc, v_mp40_flash.mdc, v_mp40_hand.mdc

animations are stored in files _hand.mdc

.mdc are loaded first, if they are not available, .md3 models are loaded

Thanks for reply!

So, to have custom weapons models in md3 format of existing RTCW guns to appear in game i need first to remove the original mdc files with the same names from game pk3 archive? Won't that prevent RTCW from launch or crash the game though? I heard, that editing vanilla RTCW pk3 archives is not recommended and I once broke a game when I messed with pak0.pk3.

You can generally extract everything from the .pk3 archives and delete the .pk3 archives

For example i would like to replace vanilla Thompson with the one from RealRTCW 4.0 for my personal use. So far i tried to do the following:

1) I removed original Thompson weapon folder from pak0.pk3 archive and placed custom Thompson files in a separate pk3 archive (z_realrtcw). However, i got a crash log message upon launching the game saying:

**************************************************
WARNING: main/pak0.pk3 is present but its checksum (1867420855)
is not correct. Please re-copy pak0.pk3 from your
legitimate RTCW CDROM.
**************************************************

OR

2) Directly replaced content of the vanilla Thompson weapon folder from pak0.pk3 archive with custom RealRCTW 4.0 Thompson files. However, that also caused a startup crash.

So, my question is: do i need to edit the game source code in order for the game to recognize those custom Thompson md3 files? I wonder how WolfETPlayer did that in his mod (he created custom launcher and dll files though).

If i choose to unpack the pak0.pk3 what difference that will make and to which directory/path i need to unpack them (i assume Main)? What i should do next? Just replace the default content of the unpacked Thompson weapon folder with custom files (including models in md3 format)?

Sorry for all those questions, but i already asked on ModDB forums few people and they didn't know. I also checked Splash Damage forums and other places.

Regards

Jakub

RealRtCW checks pak0.pk3 for originality
try renaming .md3 to .mdc in separate pk3 archive (z_realrtcw)

Meanwhile I followed your advice and unpacked the content of original pak0.pk3 archive to RTCW/Main directory and then removed the pak0.pk3. That caused startup error saying that pak0.pk3 is missing and the game didn't launch.

If I just convert RealRTCW 4.0 md3 weapon models to mdc format and put in separate pk3 archive the game will give me a warning that total vertices amount is more than 3999. That is why I would like to use md3 models instead, because they are not affected with this max vertices limit.

EDIT:

Meanwhile I solved the problem by dividing a weapon model into few smaller parts in Gmax 1.2. Also md3 format does not allow more vertices on a model in RTCW by default. WolfETPlayer (author of RealRTCW 4.0 mod) said that he needed to edit source code in order to increase vertices limit in game.