Patent attributes
According to one aspect, a printer supports transparency operations by generating mask data at interpretation stage which indicates whether each bit of a page content would be determined by the result of a raster operation or a prior destination value. The mask data can be used to complete quickly rendering of a page image once the rendering starts. Another aspect enables color fills of objects to be performed efficiently. A raster operations engine may determine whether all the points (pixels) of the object would have the same value if the raster operation is performed. If all pixels would have the same value, the value for only one pixel is computed and used for multiple pixels of the object. According to another aspect, when a pattern is to be tiled on an entire image portion, the pattern data is stored in a memory and provided as an input to rendering operation multiple times.