Contains the information about the projection of 3D-Data to the screen The matrix will be influenced by setting the FieldOfView. But you can set this directly for example:
// initialize ProjectionMatrix by a frustum ProjectionMatrix = Math.Matrix.Frustum(-10, 10, -10, 10, 2, 50); // or ProjectionMatrix = Matrix.Orthogonal(left,right,bottom,top,-20,20);