Feralidragon wrote:...invisible surfaces (which get rendered only when you're not looking at them, thus an inverse situation)... but that's the general stuff about semi-solids: use them, but wisely.
well said ferali (seems i missed another good "semisolid" party, lol
the collision error issues are imo the biggest pain-in-the-ass aspect of semisolid use, these are sometimes difficult to figure out . once you figure out whats happening with the "local bsp" and make a change to fix the problem another can pop up elsewhere, lol (so it can be like chasing ghosts for a while) that spaceport thingy will show the "rescue" aspect of semi-solid use regarding bsp cuts and hom/collision error fixes - that map (the way it was made, which is very badly btw) would not work at all if only solid brushes were used ...
some other thoughts, not yet mentioned -
1. CTF-Orbital (epic bp map) demonstrates Semi-solid use fairly well, however, the mapper's usage is debatible in some places (like the buried supports in the curved hallways ). Generally speaking though, that map shows what its intended for. notice it's not used for occlusion (view-blocking) purposes, just deco or curved corner wedges etc. things that would otherwise introduce bunches of cuts (and thus increase chance of homs and collision errors etc). there is an example of a ss causing a hom - i thought it was in this map, but i could not find it (may be in another product map) -
the mapper had a burried suuport or some such thing in the wall in a low area, right near a lift - the hom was right there, plain as day (in an epic product map, lol
2. Remember also that ss make cuts with each other, affect collision, affect light maps, have the same texture /surface properties, and can be poly-merged, etc. so they could be thought of as just another "bsp" type - only one that does not occlude, cannot be subtracted from, and will only ADD polys to a scene, and not add NODES. I always order all ss to last , and then all non-solid to last after that before i build a map)... that's just me
3. ss sometimes develop dissapearing polys on one or more parall surfaces (aka disappearing coplaner surface) ferali hints at this cuse of this - but can be fixed usually by slightly moving the bad surface off plane with the other ss brushes it is interacting with - sometimes hard to find because you have to trial and error to find the other surface since you can't use the bsp's cuts (zone portal viewport) to "find the cut lines" ... hop that makes sense, lol!
4. ss use is hinted at by the options available in the prefab list of the add brush dialog in the editor - for example, "add semi solid pillar" - well pillars are usually cylinders, and we know what those do to your cuts, lol
another one is "add invisible collision hull" - yeah, that's also a ss brush - just set to be invisible surfaces. Interstingly, when i started mapping i noticed people referring to things like "add a deco brush..." - I thought at first they were referring to "decorations" which are meshes, lol. Later i found out they were talking about ss brushes.
5. best advice, as ferali mentions, is to use them when you need to - just have eyes wide open and try and be wise about it ...
cheers
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