Rocket projectile shader

[eq]

Hi all,

I've been trying to improve my rocket trail fx and decided there was a limit to what can be done without using a shader. I threw something together quickly to get an idea, and then stumbled upon a problem back in the scripting department.

I obviously need the shader to be displayed fixed, not camera aligned, so the plan was to make maybe 2 or 4 "quad" shaders as part of the rocket projectile. However quad is perpendicular to "dir", and I needed it parallel to "dir".


I have 2 alternative but equally frustrating problems:


shader RLtrailEQ
rotate 90
size 8
interval 0.001{
normalize velocity v0
perpendicular v0 dir
inverse dir
scale velocity parentvelocity 1
emitter 0.001{
quad
}
   }



For some odd reason the shader is aligned to the map's axis (I think)...Not to velocity!

shader RLtrailEQ
rotate 90
size 8
interval 0.001{
perpendicular dir dir
scale velocity parentvelocity 1
emitter 0.001{
quad
}
   }


I guess the script is run for both values of "dir", before and after being made perpendicular.


The only other solution is to delve into "rotatearound" which seems overcomplicated. I've been using "rotate" but it only works in one axis, I have no idea how to rotate in a different axis.

Any suggestions MUCH appreciated!

[eq]

Problem solved.

////////////////////////////////////////////////////////////////earth_quake flame trail, just behind rocket (requires RLtrailEQ.shader)
shader RLtrailEQ
width 12
interval 0.001{
normalize velocity v0
inverse v0
addscale origin v0 origin 0.5
inverse dir
emitter 0.001{
size 30
spark
}
   }

Now time to draw a shader that doesn't look entirely like a child drew it with some crayola pens....

[eq]

Hmm new issues. Because I've drawn it as a spark (I think) it does not display as an animation, or perhaps I've made the shader wrong. Also, is there a way to reposition the origin that isn't affected when the demo starts getting choppy (e.g. lots of players), I saw mention of the token "once" but have no idea how to use it, what I want to do is:


once {
normalize velocity v0
inverse v0
addscale origin v0 origin 0.4
}

But wolfcam doesn't seem to support it, I suspect I'm using it wrong