   Casting shadows on a 2D image..!
  Hey all,I''m currently making an adventure game which features pre-rendered 2D images as the scenes.I''ve made it so, however, that I have 3D characters and 3D interactive objects in the scene as well.Anyways, my concern is how one would cast shadows from the 3D characters onto the 2D image.If anybody have the slightest idea, don''t hestitate to say it out loud.. heh Thanks in advance, 
  If you provide a z-buffer along with the scene image you can use it to make shadows just as if it were a regular 3D scene.  You said they were pre-rendered backgrounds.  So you should be able to create a z-buffer from the original geometry.  Also, a z-buffer would help with testing whether an object is behind or in front of part of the background image. 