Patent ID: 7061501

Claim:
A method of rendering a pencil-sketch image from three-dimensional data, comprising: determining a pencil-sketch texture for a polygon defined by the three-dimensional data, wherein the pencil-sketch texture is comprised of tiles, and wherein determining the pencil sketch texture comprises obtaining texture values for vertices of the polygon and, in a case where all vertices do not have the same texture value, assigning the pencil-sketch texture to the polygon based on a texture value of a majority of the vertices of the polygon; projecting the polygon onto a two-dimensional surface; and mapping the pencil-sketch texture onto the polygon to render the pencil-sketch image, wherein mapping comprises arranging the tiles so that there is substantial continuity between pencil-sketch markings in selected tiles, and wherein the substantial continuity is determined based on at least one of tangents to the pencil-sketch markings in the selected tiles and approximations of derivatives of the pencil-sketch markings in the selected tiles, the approximations being obtained by wrapping the pencil sketch marking in the selected tiles around edges of the selected tiles.