| 摘要 |
PURPOSE:To simplify image drawing processing and to improve the image drawing efficiency further. CONSTITUTION:Four control points used to decide a shape of a cubic Bezier curve are generated from a control point generating section 1, a curve outline calculation section 2 obtains an outer curve and an inner curve of a thick line having a line width from each control point and a curve conversion section 4 converts each curve into plural quinary Bezier curves by using an allowable approximate error by an approximate error setting section 3. Then the quinary Bezier curves obtained from the curve conversion section 4 are given to a straight line group calculation section 5, in which the curves are converted into an outline comprising straight line groups and a part surrounded by the calculated outlines is expanded in an image drawing memory 6, the result is expressed as a polygon and the inside is filled in. |
