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Fantasio

bsp visibility

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I read on the net all dcocument on bsp vibility. I dont want to implement potal in my engine, but it''s THE ONLY thing that talk about. there are an other solution than the portal to determine visibility ? or, anyone have an idea ? maybe with z-buffer of something else ?

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Part of the problem of visibility is that you need to be able to determine if one particular set of polygons totally hides another set of polygons from view no more where the viewpoint is in a given region.

From what I understand so far, there are only approximations of that. It can''t be formally calculated. How true that is I don''t know.

So a portal methodology helps to approximate what absolutely can and can''t be seen. It also helps to limit exactly what polygons you need to send to the renderer when you know they are being viewed through a portal.

I wish I understood more about it myself.

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If you don''t like portals (what I can fully understand, far too limiting), then look into occlusion culling. A good occlusion culler can totally replace a portal system, and will probably even be more efficient. And it will also work in environments where portals fail, eg. outdoor scenery.

/ Yann

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Not sure if this is what you''re asking, but BSP ususally goes with a PVS system for it''s type of occulsuion system

~Main

==
Colt "MainRoach" McAnlis
Programmer
www.badheat.com/sinewave

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Guest Anonymous Poster
I dont want to make a standard engine like quake3 or unreal... my engine is based on a bsp-tree in each octree nodes.The bsp is usefull for backface culling, frustum culling and Collision Acceleration

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I dont want to make a standard engine like quake3 or unreal... my engine is based on a bsp-tree in each octree nodes.The bsp is usefull for backface culling, frustum culling and Collision Acceleration

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