I'm working in XNA on a 2d isometric world/game and I'm using DrawUserPrimitives to draw some geometric figures...
I saw some tutorials about creating dynamic shadows but I didn't understood why they use a "3d" matrix to control the transformations since the figure I'm drawing is in 2d perspective.
I know I'm drawing a 2d figure in 3d but I still can't understand if I really need to work with the matrix.
Is there any advantage in using a 3d Matrix to control camera and view?
Any reason why I can't just update my vertex's positions by using a regular method since the view is always the same... And since I want to work only with single figures, won't this cause all the geometric figures have the same transformations simultaneously?
To understand better what I mean here's a video http://www.youtube.com/watch?v=LjvsGHXaGEA&feature=player_embedded