UDK Notes - Particles and Materials For Them
To Make Smoke
Draw a texture of a puff of smoke (with an alpha channel) and save it as a 32bit TGA file.
Make a material like below:
material
diffuse
multiply
color - vector parameter
texture(r)
opacity
multiply
density - scalar parameter
texture(g)
For non tiling textures, such as a smoke puff, set the textures wrap mode:
double click a texture, set the address x and y to "clamp"
Ramp/Gradients based on the age of the particle
You can edit the ramp to effect how the particle changes over
it's lifetime.
Use the "color over life" node in the particle editor (Cascade)
to see the curve, click the button right beside the checkbox on the node (that button makes it show in the curve editor).
Use the vertex color node, in the particles section, to get/use the vertex colors from the individual particles
in value usually means time
out is whatever color or number you want to make
When keyframing, "in" means "time"
To key the smoke fading in and out, use a points system like the following:
Keys:
0
in: 0
out: 0
1
in: 0.25
out: 1
2
in: 0.75
out: 1
3
in: 1
out: 0