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# Tri-Strips Texture Coordinate PROBLEM!!!

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Hi! That''s my first time so...don''t hurt me I''m working on a 3DS Max 4 Exporter plug-in and after coding ... well, debuging a way to build triangle strips, a PROBLEM came across: ¿How do I get Texture Coordinates correctly to match triangle strips? Little explanation (Taken from an exported cube with "Box - UVWMapping"): - Suppose that my resulting strip is: 4 5 7 1 3 0 2 ... - When you send those vertex indices to OpenGL with "glBegin(GL_TRIANGLE_STRIP)", it builds: face 4 5 7 face 5 7 1 face 7 1 3 face 1 3 0 face 3 0 2 .... . . . - Suppose that texture indices to this faces are: face 4 5 7 - 14 15 16 face 5 7 1 - 5 23 1 face 7 1 3 - 22 20 21 face 1 3 0 - 12 11 13 face 3 0 2 - 10 8 9 .... . . . - . . . - So, ie: vertex 7 has 3 different texture indices {16, 23, 22} while in my strip structure it''s only called once... I hope to make me understood, with my 2 most powerful weapons: my poor kindergarten english and my privileged crashed apple like IQ I know that Quake2 model files have tri-strip info, but I don''t understand the way it works to get texture coords. It saves again the UV coords? Any volunteers? And the question is: ¿ How can I assign those different texture coordinates to the same vertex (with OpenGL) ? Any brighter (happy face, happy face) idea... Thanks!

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Quake 2 model uses a sort of ''compiled rendering''that''s to say a mesh is optimized to be rendered using triangle strips and fans,
when a vertex joining a side of a triangle in the case of a strip or an origin of a triangle fan is duplicated along its own texture coordinates, so there are 2 ways to overcome this probelm using the immediate mode where each vertex has its own texture coordinates, but this increases by a 3 magnitude the number of vertices to be rendered for each triangle, or writing a stripping library ( or use an already done like nvida or stripe )
but also you may want to use compiled vertex arrays.
the explanation of a stripping function is long,very long to post here. if you want contact me and request the code

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if the verts are the same but the texture coordinates arent
unfortunately u need to make multiple vertices (even though theyre the same vertex)

http://uk.geocities.com/sloppyturds/gotterdammerung.html

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