# How to obtain all polygons?

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tiegudanxin    122
Hi all! How to obtain all polygons of a mesh(all polygons in a same plane,the mesh is a plane)?The mesh consist of sorts of polygons that owns n edges(n may be 3,4,5,6 and 7.... and so on) thanks [Edited by - tiegudanxin on November 21, 2007 7:33:33 PM]

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Einstone    126
There are only triangles in a mesh, no other polygons. The triangle informations are stored in the mesh's index buffer. For example, if the data in the index buffer is 4, 6, 2, 3, 2, 5, 1, 3, 5. the mesh has three triangles (4, 6, 2), (3, 2, 5) and (1, 3, 5). the number represents the corespondent vertex's poisition in the mesh's vertex buffer.

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superpig    1825
Quote:
 Original post by EinstoneThere are only triangles in a mesh, no other polygons.
No, not necessarily.

tiegudanxin, I'm not quite sure what you're asking. You've got a mesh, and you want to extract the individual polygons from it? That depends on the format you've got the mesh in.

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tiegudanxin    122
Quote:
Original post by superpig
Quote:
 Original post by EinstoneThere are only triangles in a mesh, no other polygons.
No, not necessarily.

tiegudanxin, I'm not quite sure what you're asking. You've got a mesh, and you want to extract the individual polygons from it? That depends on the format you've got the mesh in.

I draw a graphics in my graphics program,It consist of vertexs and edges between vertexs,I know position of all vertexs,I want to obtain all polygons(concave and protrude) that the graphics owns.The graphics is a 2D graphics.
Sorry,My english is not good!
Thanks!

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superpig    1825
Ah, right. Read this. What you're looking to do is to extract all the minimum cycles from your set of vertices and edges, because each minimum cycle is a single polygon.

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tiegudanxin    122
Quote:
 Original post by superpigAh, right. Read this. What you're looking to do is to extract all the minimum cycles from your set of vertices and edges, because each minimum cycle is a single polygon.

Ah, great! Thanks!