How much brush cutting is worth the improvement of nodraw?

Discussion in 'Mapping Questions & Discussion' started by Armadillo of Doom, Oct 7, 2008.

  1. Armadillo of Doom

    aa Armadillo of Doom Group Founder, Lover of Pie

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    Simple example, I have a brush against the skybox wall. Since nobody can see the back or bottom of said brush, it should be nodraw. What if however, I have 2 brushes next to the first, aligned on the side. One goes from the ground to the middle of the original, while the second goes from 3/4 of the original height to up past it. Since nobody can see the areas where brush number 1 touches the other two, in theory those parts should be nodraw. But that would involve cutting up your 3 brushes into 6. My crude picture;

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    As opposed to;
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    So which is better? In the first, you'll have textures being drawn that cannot be seen. While in the second, you have removed the excess textures in favor of chopping up the brushes like sushi. Provided the brushes line up (edges touching) the visleafs should be exactly the same. Which leads back to the original question, lol. How much of this is worth it for nodraw/hiding unseen textures?
     
  2. Earl

    Earl L6: Sharp Member

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    If the big brush is skybox, there's no point in splitting it up. If I'm not mistaken, the entire 3D skybox is rendered before, and everything else is just rendered on top of it.

    However, if it was a normal textured brush, it would be good to split it up, not only to slightly improve performance but to improve your lighting at the corners.
     
  3. Open Blade

    Open Blade L7: Fancy Member

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    Either way works - one way is less work.
     
  4. Big Lou

    Big Lou L3: Member

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    I just set my default texture to nodraw, build the geometry, and use the face edit tool to texture only what's visible.
     
  5. Armadillo of Doom

    aa Armadillo of Doom Group Founder, Lover of Pie

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    OpenBlade- yes they both work, but it's not a question of effort, it's about performance. And Earl, I was just using the skybox as an example backdrop. Though I wasn't aware that splitting brushes in such a fashion improves the light at corners.
     
  6. Earl

    Earl L6: Sharp Member

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    Another thing: My second comment only applies if the smaller brushes are func_detail. If all brushes are world brushes, they are sliced up automatically, and the hidden part is removed/not rendered with no extra effort on your part.
     
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  7. Armadillo of Doom

    aa Armadillo of Doom Group Founder, Lover of Pie

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    For reals? I did not know that. Thanks for the info m8 :D
     
  8. Earl

    Earl L6: Sharp Member

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    Yeah, if you've ever noclipped through the walls in you map, you'll notice that superfluous faces are automatically clipped and removed from world brushes.