Trail Effect

[Zappa]

Time ago I saw this trail effect in FAKK2 and American McGee's Alice (both games uses id Tech 3 engine)
And I wanted to try it in mohaa.

So, looking the Client Game Module Classes (tempmodels documentation) says:

trail( String shader, String startTag, String endTag, Float life )
    Set the tempmodel to have a swipe that follows it

I'm not sure if I was doing something wrong, but is seems like the "trail" command is broken. I only got 2 results when I try to use it
1- It does nothing.
2- The game crashes.


Fortunately, there is another command called swipeon/swipeoff, (for sword swipe effects) that does almost the same thing.
Client Game Module Classes says:

swipeon( String shader, String startTagName, Float endTagName, Float life )
    Signal the start of a swipe from the current tag

swipeoff
    Signal the end of a swipe

So yes, it is possible to make a trail effect in mohaa. I've never seen it being used before, but the 'swipeon' command is there.
You just need a model with at least 2 bones, a nice texture (the texture will look stretched, not tiled) and the swipeon command.
Most Swords models in Fakk2 have this effect, you can take a look to those models to see how the 'swipeon' command is used.

I'm also posting this "Rainbow Trail" test model.
Zappa_trail_test.pk3
A simple "dummy model" that generates a Rainbow Trail effect.

It looks like in this video:




And another video of the trail effect used in a "Pipe Bomb" model from Left 4 Dead 2