Force field shader/material for our game

[Prea]

Hi guys,

Just wanted to show the material I've been working on today. It's a WIP forcefield shader.
It's something we use in our game to prevent attackers from reaching certain areas until they have completed an objective.



The upward scrolling effect may be tweaked a bit further. It takes a lot of attention away from the rest of the scene as it's quite bright.

I hope you guys like it, feedback on the material is welcome

(our game: http://grim.morepolygons.com)

[Private Tux]

The effect is very well and unique. I bet some UDK users will do the same thing as the video for working a new game/environment (like you).

[ambershee]

It's pretty reasonable - your level design means you're going to have a lot of layered alpha behind them though, which is a bit of a performance nasty

[Prea]

It's pretty reasonable - your level design means you're going to have a lot of layered alpha behind them though, which is a bit of a performance nasty

What do you mean exactly? They're just 3 planes/layers with a not even that complex material shader. Where do you think the performance becomes an issue?

[ambershee]

I can see four layers in the video. Unreal 3 doesn't handle transparency very elegantly (it's actually a problem in many renderers) - these forcefields occupy a large quantity of screen space and can become pretty expensive to render (take a look at shader complexity in the editor, you'll probably find there are angles at which there are large areas of red / white performance). Throw gameplay in there and things can become worse; eg smoke particle systems and the like.

[Prea]

There is a lot of RED (and some white) going on in the scene, most of it seems to be caused by some kind of effect I hadn't event noticed on the ground (something like a height fog but with particles) I'll let the level designer know to make sure it gets optimized/cleaned a bit.

[ambershee]

One option regarding forcefields could be to disable a number forcefields that are currently behind other forcefields, this would mean there is only ever one requried layer.

[Prea]

One option regarding forcefields could be to disable a number forcefields that are currently behind other forcefields, this would mean there is only ever one requried layer.

Yeah depending on the performance tests we could disable all but one at the time. Gameplay-wise there is usually 1 or 2 active fields at most so we could disable the fields if necessary.