✔️ Download example fileVolumetric lighting
, also known as light shafts
or god rays
, is a lighting effect that can add depth and realism to the visuals of your map.
Creating the effect
Skew a brush to closely match the angle of your light source. Since the base faces of the brush are meant to be invisible, they should be textured with CONTENTWATER
in order to mirror the side faces of the brush, making it more realistic. Lastly, the brush should be an entity, such as func_illusionary
, with Render Mode
set to Additive
. The translucency can be set with FX Amount (1 - 255)
. If you use NULL
, not all of the side faces will be rendered at the same time, and the effect is invisible from some angles (i.e. inside or directly below the volume). Here are a couple examples of volumetric lighting with and without the use of CONTENTWATER
. A scrolling texture could also be used with a func_conveyor
Volumetric lighting textures
is basically how water is rendered in the HL engine. When the player is submerged in water and looking up, you still see the surface of the water from below. The surface has both sides of the faces visible to give this effect. It would certainly look strange without it. CONTENTWATER
gives the same effect but without the water physics and swimming, rendering all faces adjacent to it to have both sides appear. It must to be used with brush entities and not any world brushes. It is very optimized compared to hollowed out brushes to achieve the same effect. Light shafts is one of the many perfect uses for it. It can also be used for brush based plants or leaves and other things that need to be perfectly thin.