let's begin

http://docs.unity3d.com/Manual/ObliqueFrustum.html http://docs.unity3d.com/ScriptReference/Camera-projectionMatrix.html Build one camera with an off-center projection Calculate an off-center projection matrix for each camera depending on position of each camera. https://www.khanacademy.org/math/linear-algebra/alternate_bases/orthogonal_projections/v/lin-alg-another-example-of-a-projection-matrix https://www.cs.unm.edu/~angel/AW/chap05d.pdf