One of the greatest things about tessellation shaders is how easy it is to implement level-of-detail (LOD) algorithms. LOD is a general term in computer graphics that refers to the process of increasing/decreasing the complexity of an object's geometry with respect to the distance from the viewer (or other factors). As an object moves farther away from the camera, less geometric detail is needed to represent the shape because the overall size of the object becomes smaller. However, as the object moves closer to the camera, the object fills more and more of the screen, and more geometric detail is needed to maintain the desired appearance (smoothness or lack of other geometric artifacts).
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