   Creating triangles from line strips
  Hi all,I have written a rudimentary .dxf converter (to DX), and have come to the problem of taking my line strips and creating triangles for rendering in DX.  I have had a quick look around for tripling algorithms but I haven''t found anything which I can use (most google results telling me that wonderful products can triple for me!).Could someone please help me out - provide some other key-words to search on.Thanks,Steele. 
  Ok, I have come along a bit with this so I can be a bit more specific.  The part I am having trouble with is, given a particular line, how to determine which side of the line is "inside" the polygon.  C+--+  +------+|  |  | || A+--+B||  ||   +--+  +--+|   |  |  |+---+  +--+So that working around my line strip in clockwise order (this is arbitrary) from A to B, how can I tell that the triangle ABC is not within the polygon?Thanks for any help,Steele.   [edited by - Crow-knee on February 9, 2004 7:03:46 PM];  Your problem is linked to the convexity of your object.Look for tesselation of concave polygon on google.For your particular question, test if B is back facing or front facing segment [AC].- in 2d this should be testing the sign of the line equation applied on B : a*xB + b*yB +c (I dont remember how to compute a, b & c coeffs).- in 3d, the same with the plane equation : a*xB + b*yB + c*zB + d, where a,b,c are the coordinates of the normal vector, d can be found with one point of the plane 