Hello!
I want to render indoor scenes using portals and sectores. I just started and already have problem. I want to use portals as teleportes.
now:
wanted:
The blue quad is the portal and the rest is the sector. I only want to see the lines/triangles/objects inside the portal.
Is there a easy and fast way to do this? I looked for tutorials, but they couldn't help, because the used portals as doors and windows and because of this they don't have the problem.
Berion
Well isn't your blue quad a "door"? If the effect you wish to achieve is seeing something only through a certain object on screen, you could just use that door technique (probably stencil buffer + clipping plane). In more complex cases you might render the stuff on the other side of the portal to a texture and then use it on your quad or other shape.
any particular reason why you are doing it in wireframe? is this a hardware or software engine?
My own portal engine is hardware accelerated, consequently.... I just use the Z-Buffer, and don't really care about getting the specifics of clipping stuff against portals, I only test if Any portion of the next sector is visible thru the portal, then render the whole thing
One way to do this (in hardware) is to draw a quad of your portal, and use the stencil buffer... specifically:
draw your quad for the portal with writing to the stencil buffer, say value=1 then draw stuff "on the other side" but enable stencil testing with value==1.
Note: you need to draw the full quad, not jsut the outline (and of course clear all the buffers including stencil between frames).
Best Regards
-Kevin
Close this Gamedev account, I have outgrown Gamedev.
wanted: 
The blue quad is the portal and the rest is the sector. I only want to see the lines/triangles/objects inside the portal.
Is there a easy and fast way to do this? I looked for tutorials, but they couldn't help, because the used portals as doors and windows and because of this they don't have the problem.
Berion
