| 摘要 |
PROBLEM TO BE SOLVED: To reduce the overhead of the saving and replacement of values of registers by providing instructions and hardware mechanism for variably controlling the switching of register values used to access memory areas and the conversion of the register numbers according to an object of processing. SOLUTION: The registers R1 to R3 which can be set by software are used to indicate addresses of attribute data of 1st, 2nd, and 3rd vertexes of a polygon and selectors SEL1 to SEL3 select data to be set in the registers R1 to R3. Select signals S1 to S3 and write enable signal We1 to We3 are outputted from an instruction decoder. Then an instruction for setting the values in the registers R1 to R3, an instruction for switching the values of the registers R1 to R3 at the time of a strip type polygon process, and an instruction for switching the values of the registers R2 to R3 at the time of a fan type polygon process are prepared in an instruction set. |
