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Trees are hollow

The Dudinator

Grizzled Veteran
Aug 20, 2011
62
10
Netherlands
2qb6o07.jpg


Why are trees hollow :p
 
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Same reason that everything is hollow. They're made up of polygons, which are two dimensional constructs projected into a three dimensional mathematical space.

They have a height, and width, but no depth. So if you want a square box? You stick six square polygons together, and put a texture on them. Boom, you have a box. However, nothing is actually inside that box.


And to make things even more interesting, you often only have a texture visible from one direction. That is, from outside you will see the box, but if you stuck your head inside, the box would disappear as you would see right through it.



The bigger question is, how are you able to look at it from that angle?
 
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I think the question is rather why are there textures inside the tree at all? Sound like bad map optimizing to me..

because I believe with objects like that the texture is just mirrored on both sides regardless, I don't think they could do it any other way. If so I doubt it would be much of a performance gain since there are only a few trees around.
 
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because I believe with objects like that the texture is just mirrored on both sides regardless, I don't think they could do it any other way. If so I doubt it would be much of a performance gain since there are only a few trees around.

Amazing that OP has never seen this before, it is in every game that I have ever played.

IT JUST IS, it is not an error, if you want to know more about it do some research on the subject.
 
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because I believe with objects like that the texture is just mirrored on both sides regardless, I don't think they could do it any other way. If so I doubt it would be much of a performance gain since there are only a few trees around.
At least on some game engines all textures that cant be seen by players should be removed to reduce the impact on performance, very basic mapping knowledge, although I dont know about Unreal Engine
 
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It's because the tree models have flat branches that need to be seen from both sides. So the entire tree texture can be seen from both sides of the polygons. It's referred to as 'nocull', when the back/inward facing sides of polygons are allowed to render and are not 'culled' from view like normal geometry and models.

Nocull is pretty much always used on things like plants, bushes and trees to save on the polycount.
 
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