   worldcraft map files.. but not a question about intersecting planes!!
  hi,having a weird problem loading a MAP file into my OpenGL app...Basically, all vertices are being deemed as illegal after the test to see if the intersecting vertex is behind all planes.at the moment my MAP file is a simple box.iv checked to make sure my planes are being created from 3 vertices correctly, and they definitly are.iv checked that my planes arent all facing ''in'' instead of ''out'' and am sure thats not the problem.i have a funny feeling that not all my planes are facing out OR in, and that in fact some are facing in whilst others face outwards, but cannot b sure about this, although my testing suggests this is a possibility.this has been frying my brain for hours now  desperate for sum help/suggestions wot cud b wrong!!thanks in advance!Rich 
  that looks like you have some planes in the wrong direction. a simple way to do it, calcualte the centre of the box, which you KNOW should be inside, so front facing all planes. if you found a plane that is back facing the centre, here is one of the culprit, that you need to fix. for the direction of the plane, it should only depends on the winding order of your vertices in the triangle or polygon. triangle [0, 1, 2] will be back-facing triangle [0, 2, 1], because the order of the vertices is different.  ;  hi, i have a question related to quake map files, is there anywhere a document on how the data should be threaten and how to read and transform it into 3D world objects?  ;  there are loads of tutorials on quake3 bsp formats in the web, and how to use them for rendering and collision detection. google -> "quake 3 bsp format tutorial". the game tutorials site looks a good bet. http://www.gametutorials.com/Tutorials/OpenGL/Quake3Format.htmhttp://www.nathanostgard.com/tutorials/quake3/collision/the cypher engine as a few useful links regarding quake3 style rendering and dynamic plane shifting collisionshttp://www.cipherengine.com/credits.php;  hey, cheers for the advice oliii - made me find a way of checking my planes were all facing right way - turned out they were, but that led me onto looking at the vertex my intersection function was creating.. and.. after some testing, realised it was returning vertices with one or more of the xyz values inverted to what they should be... and all because of a missing ''-'' sorted now anyway ta :D ;  good good ;  "bsp"  i meant editor .MAP files.. ;  Excellent piece of documentation:http://folk.uio.no/stefanha/MAPFiles.pdfAnd some information that I found usefull (maybe not as usefull to you but anyway):http://collective.valve-erc.com/index.php?go=map_formatRead the last couple of posts on that page, specifically by nem.