| 摘要 |
PURPOSE:To draw a picture having an optional transparent rate at a high speed by using an arithmetic operation designation means to generate a picture drawn data while changing the content of the arithmetic operation so as to generate the drawn picture data thereby executing the arithmetic operation with different content for each picture element by one command. CONSTITUTION:The titled unit is provided with two arithmetic operation designation registers 15a, 15b to designate the type of arithmetic operation in a drawn picture data arithmetic unit 11. The arithmetic operation designated by the register 15a or 15b is executed by the drawn picture data arithmetic unit 11 in response to the bit information read out of a selection information RAM 16. Thus, a different arithmetic operation is executed alternately or once for plural times by one command and the picture drawing with a high degree of freedom is executed at a high speed. |
