| 摘要 |
<p>PURPOSE:To eliminate the generation of a part which is not drawn when the storage contents of a memory are rotated by an optional angle by providing a dot generator which generates the same information with drawn dot coordinates adjoining coordinates of a dot absent part. CONSTITUTION:The storage contents of a display memory 7 are drawn while rotated by the optional angle. An optional area in the memory 7 is regarded as a source area S, an area generated by the rotation of the area S is regarded as a destination area D, and two crossing lines on the memory 7 are X and Y coordinate axes. The storage contents of the memory 7 are read out by a processor 1, coordinate variation on the side of the area D corresponding to an angle theta of rotation is calculated by an X-directional straight line generator 2 and a Y-directional straight line generator 3, and an adder 4 outputs the coordinates of a next are D. If there is a dot absent part every time the generator 2 generates an output, a dot generator 5 outputs the coordinates of the dot absent part and outputs an indication signal for drawing the same dot information with the coordinates of the adjacent area D for the coordinates of the dot absent part to the memory 7.</p> |
