Unless you posted the link to that second video, I couldn't understand what exactly you wanted. Heh, I may still not be entirely sure, but here's what I think:
I've never tried anything like this before, but it certainly seems pretty cool if you got it working. Here's how I would first approach it:
O.K. I would have to make all the brushes with the affected texture applied to them a
func_brush, or some kind of brush-based-entity. I would use a
material_modify_control point entity (read up on how to use it). I would then need to make an animated texture that I would not want to repeat to give that blood vein effect all over the walls. I would tell that
material_modify_control entity to switch to that texture for all the brush based entities applied with the first static "normal" texture. It would be a smooth blend between textures. Essentially starting with a static image of plaster walls, it would then blend to the plaster walls with blood dripping down from the top, then a completely blood-ridden wall.
Now animated textures automatically repeat, so you would need to time when that animated texture would finish its first loop, and then have it on que change to the final static texture for those brushes, (it should blend from the animated one).
Another solution: In order to get that more intense feel but dynamically (say if your player would walk back out of the town, the effect would fade away to normal again); I would make a texture for a brush that would be slightly transparent with the desired effect and place a thin brush coated with it over a brush that has the "normal" or beginning texture already on it. As the player would progress through the town, or hall, each trigger that they would pass would begin setting the FX amount (0-225) of the thin brush coated with the blood effect eventually becoming completely opaque, and as the player would back up, the "OnStartTouch" trigger would apply, subtracting an FX amount one at-a-time making for a pretty smooth transition.
The rest with the damage, sound, lights and stuff is pretty strait forward IMO...
Does any of this make sense?
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Eric Lancon
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