Figure displaying device

A device for displaying plural fundamental figures comprising:

• first means for generating the start and end point coordinate data and the gradient data of the respective vectors of fundamental figures which are formed by a preset number of vectors;
• first memory means for storing the start and end point coordinate data;
• second memory means for storing the gradient data;
• display means for displaying the fundamental figures in a raster scan of horizontal lines;
• arithmetic operation means, operative during the scanning operation of a first horizontal scanning line on said display means prior to the scanning operation of a second horizontal scanning line thereon, for examining whether or not the vectors forming each fundamental figure are located on said second scanning line on the bases of the data from said first memory means and for feeding out the start point coordinate data and adding the gradient data from said second memory means to the start point coordinate data from said first memory means, when the vector is located on said second scanning line, thereby to renew the start point coordinate data of said first memory means in accordance with the sum of the gradient data and the start point coordinate data;
• third memory means having the capacity corresponding to the number of picture elements in said second horizontal scanning line and being operative to store preset data in an address corresponding to the start point coordinate data provided by said arithmetic operation means;
• and control means for displaying, during the scanning operation of the second horizontal scanning line, the data from said third memory means on said display means.