Catching an Object on Fire

Imatk

So let's say I want to catch a tree on fire and I want that tree to burn black after the fire moves up the tree like in real life.

I figure I can accomplish this with matinee and kismet, but was wondering if there was a more efficient way to go about catching a tree or something like that on fire.

Thanks for any advice

imbueFX

Well you could spawn the tree itself inside of Cascade (if your level permits it), and use a dynamic parameter in your material to animate the transition between the normal tree material and the burnt tree material.

If you want the fire the follow the contours of the tree precisely, I'd recommend making it a skeletal mesh and using a Skel Vert/Suft Loc module. You could even use multiple emitter then and have different flame types on different areas. Meaning you could have a set of joints for smaller branches, then one emitter that only emits from those joints with smaller flames. Then the trunk could have bigger flames emitting from different joints placed in the trunk.

Hope this helps!

Imatk

Yeah that definitely helps thanks man. I'm trying to figure out how exactly I would get my fire emitters to follow my transition material. Not sure how I could get that to work.

It would be cool if there was a way to spawn particles by texture.

imbueFX

Yeah that would be VERY nice! Put that on my Cascade wishlist

Vailias

perhaps drive the material transition with the distance between the object world position and another 3 vector parameter, then set that parameter to be the world location of the particle emitter center via script/kismet? So as you move your emitter the burn effect follows?

EmAr

If you are not stuck with dx9/dx10 you can go crazy with tessellation/displacement. It took me a good deal of time to work this out but it's not extremely complicated math-wise:

[ame="http://www.youtube.com/watch?v=SK6j-554CW8"]UDK fire effect with tessellation update - YouTube[/ame]

It works on a copy of the mesh. There are some panning/rotating textures which define the displacement amount and the rest is mostly colors and lots of emmissive

The best thing is that you can adjust precisely where the flames are and what areas are completely burnt.

The downside is you cannot have large flames. You can use sprites for that maybe and mix them together.