Hints and what they actually do
The compiled map contains invisible areas called portals, the
purpose of these are to split up the world into sections to allow
for VIS to calculate weather you can or cant see an area, in or
out of your view.
When compiling map with bsp.exe,you will see .prt created, this
is the invisible portals/areas created
Most of the time a portal will be created as simple as can be,
usually to long, the longest portal you will find is 1024 units
This is because bsp automatically divides map along the X,Y axis
every 1024 units, it also makes tris (triangles) along these lines.
I have also noticed that if a lot of brushes have been made in
same direction, bsp will split the portals in those directions
In pic 1 you can see the portals (purple) with players in them
(red) . Even though the players cannot see 1 another, the portals
that they are in can see each other so tris around the corner
will get rendered (see pic 6), if I place a hint brush to split
the portals (purple ones)along the inner wall, it will make VIS
think that the portal than I am standing in CANNOT see the portal
the other payer is standing in, thus not rendering what's contained
in that portal and beyond. Players, weapons, armor and most importantly
triangles wont get rendered, this is what causes bad frame rates,
especially when it can be avoided
Sometimes with a hint placed, you will notice it made tris different,
its not designed to effect tris directly, but because it changes
the map structure it will compile brushes in a different order.
Also note if a HINT brush it placed threw a detail brush, it WILL
split it (make tris).
pic 2 is with q3rad's portal viewer portraying the purple portals,
that are in pic 1
pic 3 is my hint placement to brake up the guilty portal that's
way to long
In pic 6 you are standing in a portal that can see were the bin
is, after we split it with a hint(as in pic 3), you can see in
pic 7 that the bin doesn't get rendered.
There is a different technique I prefer to use when I am getting
pushed for r_speeds, In pic 8 you can see that the hint is placed
on an angle, the principle is still the same, were the purple
portals still cannot see 1 another but it allows player to move
further towards the next room
With pic 10 I have walked just past the hint brush, also note that
it DIDNOT create tris along the hint placement. The next picture
shows how effective my hint placement was, I can almost walk up
to corner and its still not rendering the bin. If there was a huge
and detailed room after bin, then yo understand how effective this
will be on gameplay .