Real time snow accumulation

NAIMA

Hi I am just out of curiousity asking if there is any engine out there that allows for a realistic real time snow cumulation in game world effect.

I do not mean a layer overshader of objects that pasts over a white or snow texture according to the mesh orientation but something that increases over time the thickness of snow and cumulates over meshes.

Thats the only I found

http://www.ep.liu.se/ecp/013/007/ecp01307.pdf

ZacD

For solid meshes in UDK, world position offset would work well and be extremely cheap performance wise.

NAIMA

Duplicating meshes? Any sample videos?

NAIMA

So no game engine is yet able to perform this ?

passerby

Someone already game you a possible solution, use a shader that blends snow into the up-vector, that also does a world position offset in the vertex shader to deform the geometry, than you can drive the material with a multiplier that is hooked in variable that is animated over time.

Der Hollander

Would ObjectWorldPosition work better? The last time I used Transform World Position, it did not discriminate object space, so the parameters only worked at a given world height, rather than applying a up-vector transform on a per-object basis.

passerby

Der Hollander wrote: »

Would ObjectWorldPosition work better? The last time I used Transform World Position, it did not discriminate object space, so the parameters only worked at a given world height, rather than applying a up-vector transform on a per-object basis.

i just got the object postion, and used that to offset the value im doing the worldpostion offset by.

Eric Chadwick

For example

[ame="http://www.youtube.com/watch?v=Q6h4onjwYDM"]Snow Build-up shader - YouTube[/ame]

BARDLER

Hope this helps
[ame="http://www.youtube.com/watch?v=lH6SIFQ0ROE"]UDK Tutorial SnowRock (Z-ax Orientated material) - YouTube[/ame]

NAIMA

Hi that looks interesting and promising , but do you have a video of ingame performance? like a scene with snow cumulating over time? How would that perform overtime?

passerby

not expensive at all since all your doing is animating a material parameters with matinee, in the video he uses a time node, but you could simply just animate the needed material paramaters