| 摘要 |
PURPOSE:To simplify the processing and to improve the drawing efficiency. CONSTITUTION:A control point generation part 1 generates four control points which decides the shape of the three-dimensional curve. A part 2 calculating the outline of curve obtains the outer and inner curves when a line width is taken from each control point. A curve conversion part 4 converts it into plural three-dimensional Bezier curve by using the allowable approximate error of the part 3. A part 5 calculating the straight line groups makes the three- dimensional Bezier curve obtained by the part 4 straight and calculates the outline consisting of the divided straight line groups. The part surrounded by the calculated outline is developed to a drawing memory 6 and is represented by polygon and then it is painted over. |
