A Geometry Engine Interface for 'grid'

This report describes a new function in 'grid' called grobCoords and a new package called 'gridGeometry' that combines grobCoords with the 'polyclip' package to provide a geometry engine interface for 'grid'.本报告介绍了'grid'包中一款名为grobCoords的全新函数，以及一款名为gridGeometry的全新扩展包。该扩展包将grobCoords与'polyclip'包相结合，为'grid'包提供几何引擎接口。