Patent ID: 6236410
Filing Date: 2001-05-22
Classification: G06F,G06T

Abstract:
A method of rendering an image, the method comprising the steps of:creating an expression tree representing the image, wherein the expression tree comprises leaf nodes and group nodes comprising graphical elements and operators, respectively;converting the expression tree to a corresponding list of instructions;maintaining an active list of the instructions and graphical elements of those instructions and graphical elements that effect a currently scanned scan line; andrendering the image on a scan line basis in accordance with the active list of instructions and graphical elements for the currently scanned scan line, wherein said creating step includes a step of:optimizing the expression tree by constructing, for each node in the tree, a bounding box of those areas of the graphical elements of the node and its descendent nodes of the expression tree which are active in the production of the image, and wherein said converting step includes a step of:generating from the optimized expression tree the list of instructions and graphical elements sorted in scanline order.