Quote from Brainstone on June 14, 2011, 1:02 pm

Create a thin Brush slightly above the surface you want no paint on, then press ctrl + t and choose trigger_paint_cleanser. Now any sort of paint will not be able to pass the trigger.

Quote from Dr_D1cK_H4nDleR on June 14, 2011, 11:54 pm

Thank you very much!

Quote from The Irate Pirate on June 15, 2011, 8:33 am

If I had thought this possible I would have solved quite a few Conversion Gel related exploits in my map.

Quote from Hober on June 15, 2011, 10:17 am

TBH, giving your player conversion gel and then only letting them put it where you want it is one of the most frustrating ways to make a puzzle.

Quote from {SOAP} Pm@c on June 15, 2011, 12:45 pm

How would this be accomplished using a grating texture (such that the gel would go through the grate and down below the grating)?

Quote from Vordwann on June 15, 2011, 2:36 pm

Grating textures are programmed to allow paint to go through them, as is seen in many of the old aperture maps.

Quote from Mevious on June 15, 2011, 4:18 pm

Hober wrote:

TBH, giving your player conversion gel and then only letting them put it where you want it is one of the most frustrating ways to make a puzzle.

This. If you must block paint on a normally paintable surface, then please make it very obvious to the player which surfaces are paintable and which aren't.

Quote from The Irate Pirate on June 15, 2011, 4:30 pm

It wouldn't be everywhere, it was just on a wall where you shouldn't be able to get to without a great deal of trial and error.

Quote from Mevious on June 15, 2011, 4:47 pm

The Irate Pirate wrote:

It wouldn't be everywhere, it was just on a wall where you shouldn't be able to get to without a great deal of trial and error.

And then if the player spends time and effort trying to get paint to that surface and it magically doesn't stick, that player is rightfully going to be really pissed off. This is exactly the kind of thing you should avoid.