| 摘要 |
PURPOSE:To reduce the load of a CPU and to rapidly form an input parameter by expanding or contracting a vector to be drawn at magnification indicated by a scale and finding out a direction code and an inclination parameter by referring an inclination table. CONSTITUTION:A multiplier 14 multiplies a line length l by a scale 128 s and a shifter 15 shifts the multiplied result by 7 bits to the right. On the other, an adder adds an inclination angle theta to a rotating angle delta and extracts the previously registered direction code and inclination parameter (a), (b) by refer ring an angle table and the inclination table 20. A larger value out of previously registered 2<10>-fold cosine value 1024 costheta ' and 2<10>-fold sine value 1024 sintheta ' is extracted, a multiplier 18 multiplies the extracted value by the shifted result l.s and a shifter 19 shifts the multiplied result by 10 bits to the right. The output of the shifter 19 is inputted to a vector drawing device 11 together with the direction code, inclination parameter (a), (b) and the start coordinates X, Y of the vector to be drawn and the vector is drawn on a drawing memory 12. |
