Patent ID: 7847798

Claim:
A computer-implemented method, comprising: receiving artwork input at a graphics processing unit (GPU), wherein the artwork input comprises one or more dirty regions and one or more clip paths, and wherein the GPU comprises a depth buffer and a stencil buffer; performing a culling operation on the artwork input, comprising configuring the depth buffer to reject pixels located outside a union of the one or more dirty regions, wherein configuring the depth buffer to reject pixels located outside the union of the one or more dirty regions comprises: setting bounds of a viewport to a smallest rectangle comprising the union of the one or more dirty regions; assigning a first value to pixels in the depth buffer corresponding to pixels in the viewport; assigning a second value to pixels in the depth buffer corresponding to pixels in the union of the one or more dirty regions; and rejecting the pixels marked with the first value after assigning the second value; and performing a clipping operation on the artwork input, comprising configuring the stencil buffer to reject pixels located outside an intersection of the one or more clip paths.