Window control device for displaying a plurality of windows on a display screen

摘要

The window control device of this invention for displaying a plurality of window regions superimposed on one another on a display screen includes: mask data production means for producing mask data so that whether or not pixel data for displaying a predetermined window region among the plurality of window regions should be displayed on a predetermined pixel of the display screen is determined before the predetermined window region is displayed, and subsequently whether or not pixel data for displaying the predetermined window region should be displayed on at least one pixel which is consecutive to the predetermined pixel is determined, so that the mask data can indicate whether or not the respective pixel data should be displayed on the predetermined pixel and the at least one pixel; and pixel data renewing means for renewing the pixel data for the predetermined pixel based on the mask data, as well as the pixel data for the at least one pixel which is consecutive to the predetermined pixel based on the mask data.