Controlling portals

Controlling portals is nearly the basis for any puzzle-based Portal map. If your player can create portals anywhere, most puzzles become trivial and not fun. Here we will tell you how to force the player into using portals on certain areas and also how to help them control their portals.

Textures

Textures which have $noportal 1 set in their .vmt file will be non-portable. For the default Portal texture set, most textures that are concrete are portable while metal ones are not. This is the main way to prevent players from putting a portal on a wall.

func_noportal_volume

This brush entity stops any portals from being made within it. To create one, just cover an area you wish to disallow portals (like the ceiling and floors of an elevator room) in a brush textured with tools/toolsinvisible and tie it to the entity.

func_portal_bumper

This brush entity is used on the edges of portable and non-portable textures. If the player shoots his/her portal not fully onto the portable surface, this entity will "bump" it so the portal is fully on the portable surface. To create one, create a brush just in front of the edge where the two surfaces meet, cover it with the texture tools/toolsinvisible and tie it to the entity.

trigger_portal_cleanser

When a player passes through this trigger, all of the current portals on the map will vanish. It can also be set to dissolve any physics objects (like cubes, spheres or cameras). To create one, make a brush across the area where you want it to trigger, apply the tools/toolstrigger texture to it and tie it to the entity. This is mostly used in creating a fizzler.

func_portal_orientation

This brush entity rotates portals based in it's volume so they are always facing a certain direction. To create one, make a brush textured with tools/toolsinvisible and tie it to the entity. Then set the AnglesToFace value to whichever direction you want the bottom of the portal facing.