TESSELLATION METHOD USING DISPLACEMENT FACTORS

摘要

A tessellation method uses both vertex tessellation factors and displacement factors defined for each vertex of a patch, which may be a quad, a triangle or an isoline. The method is implemented in a computer graphics system and involves calculating a vertex tessellation factor for each corner vertex in one or more input patches. Tessellation is then performed on the plurality of input patches using the vertex tessellation factors. The tessellation operation involves adding one or more new vertices and calculating a displacement factor for each newly added vertex. A world space parameter for each vertex is subsequently determined by calculating a target world space parameter for each vertex and then modifying the target world space parameter for a vertex using the displacement factor for that vertex.

主权项

1. A method of performing tessellation in a computer graphics system, the method comprising:
calculating a vertex tessellation factor for each corner vertex in one or more input patches representing one or more surfaces to be rendered by said computer graphics system; performing tessellation on the one or more input patches using the vertex tessellation factors to generate a plurality of primitives defined by vertices, the tessellation comprising adding one or more new vertices and calculating a displacement factor for each newly added vertex; and generating a world space parameter for each vertex by calculating a target world space parameter for each vertex and modifying the target world space parameter for a vertex using the displacement factor for that vertex, wherein the modified target world space parameter is used in rendering an input patch in a display space of said system.