Thin Blue Line: 3d Camera

Wednesday, 26 December 2012

3d Camera

To get a better understanding of 3D cameras, imagine you are shooting a movie. You have to set up a scene that you want to shoot and you need a camera. To get the footage, you'll roam through the scene with your camera, shooting the objects in the scene from different angles and points of view.The same filming process occurs with a 3D camera. You need a "virtual" camera, which can roam around the "virtual" scene that you have created.Two popular shooting styles involve watching the world through a character's eyes (also known as a first person camera) or pointing the camera at a character and keeping them in view (known as a third person camera).This is the basic premise of a 3D camera: a virtual camera that you can use to roam around a 3D scene, and render the footage from a specific point of view.Understanding world space and view space To code this kind of behavior, you'll render the contents of the 3D world from the camera's point of view, not just from the world coordinate system point of view, or from some other fixed point of view.Generally speaking, a 3D scene contains a set of 3D models. The models are defined as a set of vertices and triangles, referenced to their own coordinate system. The space in which the models are defined is called the model (or local) space.