   How do I change this orthographic projection into a perspective FOV?
  Folks,  I have a top-down spaceship shooter that is rendered in 3D using an orthographic projection.  The camera is always centered on the player's ship.  Because the projection is orthographic, all of the ships are flat on the screen as if it were a 2D game.I want to experiment with adding some perspective to ships that are distant from the player's ship.  I cannot figure out how to make a perspective projection matrix and corresponding view matrix to achieve this effect.Here is my current view, and projection: Matrix worldMatrix = Matrix.Identity;   Matrix view;   Matrix viewInit = Matrix.CreateLookAt(new Vector3(0, 0, 500), new Vector3(0, 0, 0), Vector3.Up);   Matrix projection = Matrix.CreateOrthographicOffCenter(0, 1280, 720, 0, -100000, 100000);I know I need a tight Field of View and a camera pulled back pretty far to achieve the same effect.  How do I do that?   
  first off, i don't like the use of new in your CreateLookAt() function. If your not explicitly deleting these vectors you have a memory leak. the D3DX docs are a great resource for matrix related info. You can see how the persective matrices are created, and then use numbers that work for you. The screen size of your orthographic matrix is equivalent to the size of the near plane for a perspective projection. You can use trig to find a suitable FOV angle to give the desired width/height of the near plane, based on the distance the nearplane is from the origin of viewspace.   ;  First, as Burnt_Fyr implies, you'll just have create a perspective projection with some parameters you like.Quote:..to achieve the same effect. How do I do that?You can't, at least, not "the same." An orthographic projection maps a box in the world to the screen. A perspective projection maps a truncated pyramid in the world to the screen. They don't (and can't) represent the same volume of world space. The perspective volume can be smaller or larger than the box, but it can't be the same.E.g., if a ship wanders outside the box and disappears from the ortho view, it may still be in the perspective volume and be mapped to the screen.   