| 摘要 |
PURPOSE:To process only an objective block and to shorten an analysis time compared with the analysis of all contents in a window by adding information bits indicating whether data are contacted with the window or not to the data of respective lines of a graphic. CONSTITUTION:When a block other than an object is laid over an area set up by the window and its outside area, a differential signal of a window signal is written in a memory on the boundary of the window. In case of analyzing a block, a block other than the objective one is removed and analyzed while observing the contents of the memory. Namely, the whole screen is scanned and the analysis of connection is executed based on data in each line on the screen. At that time, a status bit indicating a block laid over the window is remarked out of the processing data, and when the bit is set up, the data of the block are not analyzed. Thus only a necessary block is analyzed. In case of simultaneously analyzing a block laid over the window, analysis is executed by neglecting the status bit. Even when a block is laid over the horizontal boundary of the window, the differential signal of a differential circuit coincides with the window signal. |
