网格化[tessellation]即把凹多边形,包含洞,岛的多边型,或者自交叉多边型划分为简单凸多边形的过程.OpenGL为了能快速渲染多边形，只能直接显示简单凸多边形[多边形中任意两点的连线上的所有点仍属于此多边形],对凹多边或者自交叉多边形渲染结果将不确定。在渲染复杂多边形时，常常需要将复杂多边形分解成容易渲染的简单多边形，OpenGL中的使用函数库中提供网格化的函数以通过多边型轮廓线生成简单多边形，从而渲染复杂多边形。

-Grid [tessellation] that is concave polygon contains holes, the island of multilateral type, or from cross-multilateral-type convex polygon is divided into easy process. OpenGL for fast rendering polygon, can only directly show that a simple convex polygon [arbitrary polygon two points to connect all the points still to this polygon], the multilateral or concave polygon rendering results from the cross will be uncertain. In rendering complex polygons, it is often required complex polygon into simple polygon rendering easier, OpenGL use library provides a function of grid through multilateral type contour line generates simple polygon, thereby rendering the complexity of the polygon.