Quote from Michael GreenwoodI have a couple conceptual questions that should be easy to answer:
1) Should I avoid the use of trees in mid as cover/props as they are unpredictable for cover, grenades and clipping?
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4) Should metal railings (like the ones on inferno balcony) be set to not block bullets? Or be really easy to penetrate? I like metal railings for the visibility (and theme) but I don't like the unpredictability of the clipping.
1) You should be aware that trees can have a collision model that is sometimes not accurate to the tree model itself at all (especially some of the older stock models). Other than that, it's not something that should be avoided per se, although it probably depends on the situation. You can check out the collision model in Hammer by clicking on the CM button ([Blocked Image: http://i.imgur.com/J501858.jpg]).
2) + 3) Can't really comment on them as they're map specific and I didn't playtest your map yet.
4) Always make railing non-solid to bullets (and possibly grenades). It's really frustrating if your shots don't hit the target because of small bits of a railing.