For Example, in some 1st person shooting game, when a person get shot, we can see some blood painted on the body. Actually, how to do it? Is it using multi texture? Or just drawing on the existing texture?

That would typically be done with a "scar", or a patch texture applied on top of the original using multi-texturing. The same method is used to make explosion marks on hillsides, etc.

As an alternative, some games will use full skins that represent full health, medium damage and severe damge just to give the effect of bloodmarks and bruises as the target takes more and more damage. Once the target reaches a critical amount of damage, the skin suddenly changes to reflect the next damage level.

There could easily be other ways to do it, but I think multitexturing is the most straightforward, from my point of view.

If the original texture were modified, then ALL characters using that texture would show the damage. I suppose, if there is enough memory, each character could use a separate, individual texture, and those textures could be modified on the fly, allowing anything to be applied to a skin without needing to use multitexturing to render it.


[edited by - Waverider on November 12, 2002 10:47:57 PM]

multitexture is normally not used (ie quake3/UT dont it)
just draw another texture over the already existing geometry (u might want to clip this texture to the already exist geometry)
sometimes this is called ''decals'' search that + u might get some hits

http://uk.geocities.com/sloppyturds/kea/kea.html
http://uk.geocities.com/sloppyturds/gotterdammerung.html

quote: Original post by zedzeek
multitexture is normally not used (ie quake3/UT dont it)
just draw another texture over the already existing geometry (u might want to clip this texture to the already exist geometry)
sometimes this is called ''decals'' search that + u might get some hits

This sounds like multipass multitexturing. I believe that''s a lot slower than actual multitexturing.