   sword trailing in games
  I would like to know how sword trailing is done in games..Is the bone position of the sword calculated and a polygon is rendered ? or what other techniques r used? 
  You can have a trail model, and move it''s vertices so they follow the sowrd with different time delays. You could also record the sword movement per frame into a buffer or something, and move each vertex pair in the trail model a few frames after the sword has moved. ;  probably quadstrips. Get two vertices on the sword (the one on the tip, on further down the blade), as it moves, build a quad strip from previous stored vertices, fade quads further down the list according to time. Like skidmarks, and other trailing effects. You might want to interpolate the vertices along a spline, for extra prettyness.  //  [t = t0]//|\//   -----------------||_____//   P0-------P1------||------//   +--------+  |/////////  [t = t1]//|\//   -----------------||_____//   P2-------P3------||------//   +--------+  |///   \    \//    \    \//\    \// +---------+//P0    P1//////  [t = t2]//|\//   -----------------||_____//   P4-------P5------||------//   +--------+  |///   |   |//   |   | //   |   | //   +--------+//   P2   \P1//\   \ // \   \//  \   \//   .- - - - . //  P0   P1 (fading away);  just like med10n said, basically ;  I noticed Prince of Persia.... what i saw was that the prince slashing of the sword looked very smooth... as of in many games... they seemed so seamless... could they have been done with the same concept of generating polygons on the fly...;  I don''t really see any other way, given the complexity of the animations. Quadstripping is a proven technique. It''s efficient enough and easy to implement. It''s all stack management, You can try it quickly, with triangle lists, on a falling and spinning object for example. They can possibly interpolate the points with a cubic spline or others, to get extra smoothness. But given the already high quality of the animation, and the fact that it''s already interpolating bones (for slow motion), i don''t think it would be necessary.  ;  i completely agree with the quadstripping concept... it sounds completely logical to me on how trailing is done...  ;  Almost always, though, you will need to do some kind of curve interpolation on the points you get, then use those to build the strip.  Swords tend to move very fast, so even sampling at 1/60fps often isn''t enough.  You still need to interpolate between them to make things smooth. 