Invisible brush that blocks light?

I’ve been making a map and there is a cave with displacements and the light will bug out and draw light through some of the edges. Is there any invisible brush that blocks light?

Theres a texture called light block or block light. Just cover a brush with it.

blocklight texture

From what I recall, “tools/blocklight” applied to a world brush will cut world geometry at compile time. May I suggest instead creating a world brush, applying nodraw to it (instead of blocklight), tying it to a func_brush, and setting it to cast shadows?

Sure its an extra entity, but this way your world geometry doesn’t needlessly get chopped up - you’re also using the efficient nodraw texture to boot.

I dearly hope you aren’t saying: ‘use nodraw whenever humanely possible because it helps’

I’m merely saying that nodraw applied to a face is a face not rendered - as opposed to say invisible, as technically its still rendered by the engine, despite it being not visible like nodraw.

Setting the func_brush to cast shadows tells the compiler to look at the physical shape of the brush for raycasting simulation. No need to actually render the surfaces of the brush if you don’t need to.

That’s not to say that I completely understand the blocklight texture - it may be like nodraw, in that it too isn’t rendered either, however I can’t say that for certain.

Your nodraw and func_brush idea is basically what blocklight does anyway, with less use of ent_data.

Except that blocklight applied to a world brush will cut other world brushes at compile time, convoluting your polycount. Using a func_brush with nodraw applied to it ensures your polycount does not increase due to extra unnecessary cuts, while achieving the same result of blocking light without being seen (and ensuring the faces of said func_brush aren’t rendered).

If blocklight isn’t rendered (like nodraw), then substituting that onto the func_brush is essentially the same thing. The main idea here is to reduce cuts in geometry by tying the brush you want to block light to an entity. I’d rather a small bump in my entdata count than extra unnecessary polys - especially if your brushes blocking light are at odd angles or aren’t cuboid in shape.

Edit: Come to think of it, you would be generating more visleafs as well as creating extra faces. The point I’m trying to make is that entities don’t cut geometry, but can still block light.


Tying it to an entity is uneccessary as it doesn’t break visleafs, I can’t think of any other reason why you would tie it to an entity.

I think the word I’m looking for is: zing!

Here’s a reason to tie it to an entity, when you don’t know what you’re talking about :v:

From the last time I used Hammer with blocklight, it cut up my world brushes as if it were any other solid unbound to an entity. It may have changed, and I could be wrong.

Edit: Turns out I was wrong, blocklight has changed since the very early HL2 days - it no longer cuts world geometry. Ignore my previous suggestion, you learn something new everyday. :slight_smile:

The VDC page for blocklight even says it cuts world geometry, looks like it needs to be updated.


God damnit stop bolding random words.

Either it’s just random, or if you are actually inferring something it could make you sound like a prick. :v:


Deal with it.

I don’t like it when you talk in bold.

Best avipost combo yet.