| 摘要 |
PURPOSE:To remarkably decrease the number of times of input/output access required for a graphic operation of once, by constituting graphic data of relative coordinates from a reference point having each component element of a graphic form, etc. CONSTITUTION:A vector P regarding an original point G of an absolute coordinate system of an optional point f1 on a two-dimensional graphic form F is constituted of the following 4 elements and is stored in a storage file. (1) an absolute coordinate value of an original point (g) of a relative coordinate system, which becomes a reference point of graphic data, that is to say, a vector 0;(2) a scale value (s) showing size of the graphic form; (3) a rotary matrix R showing the extent of rotation of the graphic form; and (4) a relative coordinate value from the reference point (g), that is to say, a vector C. Each point f2, f3 is also stored in the same way. Accordinly, the parallel movement, magnification, reduction, rotational movement, etc. are executed if only the elements 0, (s) and R are changed, for which the central processor accesses only the block in which the elements 0 (s) and R have been stored. |
