skip navmesh generation on many situations

[illwieckz]

• skip navmesh generation in playerclip content but still generate on playerclip surface
• skip navmesh generation in nodrop content (usually used in bottom of pits-of-death where players cannot go without dying)
• skip navmesh generation in lava and slime content (and their surface should already not be solid so already skipped)
• skip navmesh generation on common/outside material even if using a playerclip surface

[illwieckz]

We may also want to skip navmesh generation on lava and slime content, one problem is that bot may need a navmesh to get out of the lava/slime, but on the other hand if we generate navmesh on lava or slime, bots will run into them.

[illwieckz]

Having a bot being trapped and then dying in lava (or slime) is less a problem than having it running into lava (or slime), so I added them to content exclusion.

We may also trigger bot escape code in gameplay as soon a bot touches lava or slime anyway.

[illwieckz]

Ah no, something is wrong in my patch, it skips a surface from a brush having playerclip (which is not wanted) instead of skipping a surface from a brush inside a playerclip brush (which is wanted).

[illwieckz]

This patch is totally wrong and does not do what it claims to do.