Analysis and Research of Dynamic Observation Transformation Based on the Size of 3D Scene

In the actual project, when the three-dimensional scene is observed, the three-dimensional scene and the observer appear in the different observation matrix (viewpoint position, projection center and its upward direction), because the size of the observed object is not completely surrounded. Dislocation relationship, resulting in the view display is missing, not the ideal projection view, to the development of the system to bring confusion and interference. Therefore put forward a feasible method: in the first place, according to the actual size of 3d scene, define a completely view sphere to surround the scene, spherical reference point as the point of view, its center point as center of view, this two points decided the projection direction; Finally on the projection direction, according to the 3d scene actual size y determining the minimum observation volume to surround the 3d scene. Experimental results show that the transformation method for 3d scene observation, can easily determine the view matrix and projection matrix, improve the efficiency of the development of 3d graphics system.