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it'll b another 1 on my todo list but i'm getting through themThis is better than the tuturial lolTheStorm wrote:During compile the map will be split up into "a lot of" portals. Portals are like boxes and when you are in game you move between these invisible boxes. You don?t see them but you are always inside a portal.
It is the structural brush faces that cause the split. The Vis process then calculates what the portals can see. It calculates which other portals that can be seen from one portal. This is important for FPS later on in the game! Because when the player are inside a portal only that portal and the others that the compile process have calculated as seen from that portal will be drawn. The rest will not be drawn! The thing that blocks the view between portals is the structural brush. As I said, if you pretend that a portal is a box and you from that box can draw a straight line to an other box without passing through a structural brush then that box (portal) will be able to see the other box (portal). If it?s not possible to draw a straight line between them then it will not be able to see it.
ALL structural brushes causes split, even if the brush is only 1x1x1 units. The problem for most mappers is that they don't have a clue about this and in 99% of the cases they will end up with a map where every portal can see (almost) every other portal. That basically means that the whole map will be rendered wherever you are, that will of course give you low FPS.
More structural brushes will cause more splits that will rapidly increase VIS data. VIS data is not a bad thing but you will need the "right" VIS data. With some knowledge of this you can plan your map so that the structural brushes will cause splits into portals (boxes) in such way that you know that they won?t see to many other portals (boxes). Some brushes will never create portals that help your FPS, example a small sign on the wall (1 unit thick placed in front of the actual wall). That brush will cause a split for each side except the backside, which are aligned against the wall. The portals created will never help the map and the sign brush will never block the view between portals.
In such a case as mentioned above the brush should be turned into a ?detailed? brush. That brush will be ignored during compile. It will no longer cause any splits (new portals) but it will not be able to block any views either. That doesn?t matter in the case above since it would not have blocked any views if it were left as a structural brush either. You will never notice any difference in game?the sign will look the same!
Bah!! It?s difficult to write something in a post and make sense?I tried to make a tutorial about this. Still most people have problems understanding it. It?s really difficult to explain, I did not understand anything of this either but one day it suddenly became clear! As soon as it happens to a person?they will have no problem understanding my tutorial (but then it?s to late. he he). I really tried to write the tutorial without using to many difficult terms. Still there is a part in it that have some of these terms and that should be read too! Read it several times!
There is also a link in the tutorial to a site ?spog?s? where you can read more advanced stuff about it.
Newer game engines don?t work in the same way as the quake3 so hopefully it will be easier to map in the future. There is no VIS process; it?s a real time calculation of what can be seen and what can?t be seen.
Below is a link to my tutorial about VIS, it also have a part about detail brushes! For Vis_leafgroups check the documentation about manual vis that came with Spearhead SDK. But don?t use it to the same extent as they have in their example map ?Berlin?.
VIS For Dummies
