| 摘要 |
<p>A video picking and clipping method and apparatus are described. The picking method and apparatus comprise: A CPU and a direct memory access (DMA) circuit which is used with a graphics microprocessor (G mu P) for virtually redrawing a display list from a system memory of objects in a bit map. A starting address and a number corresponding to the number of instructions in a segment comprising a plurality of display lists are sent to the DMA for this purpose. When the coordinates of a pointer match the coordinates of a selected data object, a pick interrupt signal and special pick instruction is sent to the CPU. The CPU then uses the starting address of the display list of a selected object from a table to generate a new display list to perform a pre-selected operation on the selected data project. The clipping method and apparatus comprise a plurality of data planes for storing data objects, a match plane for storing a clipping object and a one-bit register. In use, the pixels in the data and match planes are scanned. When a match occurs between a pixel in the match plane and the contents of the one-bit register, a match signal is generated. The match signal enables the data planes to re-store the corresponding pixels of the data objects in the match planes.</p> |
