OpenGlToCameraHelper

Helper class to convert matrices used by OpenGL to draw a scene into its corresponding pinhole camera.

Typically, when using OpenGL, a projective matrix defines the projective geometry (i.e. frustum) of the scene, using parameters such as field of view, near and far planes.

OpenGL typically also uses a model-view matrix, which defines the amount of translation and rotation between the camera and vertices to be drawn in the scene.

Using both a projective matrix and a model-view matrix, the corresponding pinhole camera can be estimated.

If a pinhole camera to convert to Android view coordinates (where y coordinates increase downwards), please use one of the methods provided in OrientationHelper.