Display data memory

A graphic display data memory device comprising:

• a plurality of interconnected modules, each controlling a pixel (i, j), and each said interconnected module for pixel (i,j) comprising:
• (a) interface means, connected to receive input from all adjacent modules which includes a control digit, said adjacent modules including module (i-1, j), module (i+1, j), module (i, j-1) and module (i, j+1) and to provide output to all of said adjacent modules, said interface means further comprising a first terminal adapted to receive said control digit thereon, and a second terminal for receiving a boundary indicative signal thereon, said boundary indicative signal having a boundary state which indicates that said module (i, j) is a boundary module, and a non-boundary state indicating that said module (i, j) is not a boundary module;
• (b) a plurality of means for selecting an active control digit, among any of said inputs from said adjacent modules;
• and
• (c) latch gating means, receiving input from said control digit selecting means and from said interface means, for receiving said control digit from either of said first terminal or from said control digit selecting means, and responsive to said boundary indicative signal for:
• (a) producing a signal to control said pixel (i, j) when said boundary indicative signal is in said non-boundary state;
• (b) producing an output signal indicative of said control digit and passing said output signal to said interface means when said boundary indicative signal is in said non-boundary state, thereby passing said output signal to all of said adjacent modules (i-1, j);
• (i+1, j);
• (i, j-1);
• 1;l );
• (i, j+1);
• and
• (c) when said boundary indicative signal indicates a boundary state, not passing said digit to said output.

A method of controlling the values of a two-dimensional array of connected pixels defining an image area comprising the steps of:

• labelling a plurality of pixels in the array and bordering a selected region of the image area with boundary indicative signals;
• applying a pixel value control signal to one of the pixels within the region;
• subsequently propagating said pixel value control signal to all pixels connected to said one of the pixels and all pixels connected to those and so on to propagate the pixel value control signal to all pixels within the image area except those pixels labelled with boundary indicative signals and beyond;
• continuing said propagating until all pixels labelled with boundary indicative signals have been reached;
• and
• setting all pixels to which the pixel value control signal has been propagated and applied to a predetermined regional value, to fill the whole of said selected region of the image area with pixels having said predetermined regional value.