Abstract: A circuit for generating a plurality of moving or fixed objects on a video screen, more specifically for a video game. The circuit uses a topological memory 20 which represents the picture element by element, and an object memory 31 in which objects are defined by consecutive line segments. The addresses of the line segments are sequentially loaded into the topological memory. A picture generator 26 scans the contents of the object memory 31, under control of the topological memory 20, to define at each instant the colors to be displayed on the screen. Updating the topological memory every field with new line segment addresses changes the display positions of the objects every field thus giving motion to the objects.

Abstract: A system for generating color video signals, such as a game and a removable cartridge intended for such a system. Signal generating system comprising a storage cartridge (1), manual control (2), a data handling microprocessor (3), a main generator (4) for generating a synthesized picture and producing color signals R, V, B in the form of quantized values and producing synchronizing signals S together defining a main picture. Added to the main generator (4) is an additional generator (6) which is synchronized by S and produces the signals R.sub.1, V.sub.1, B.sub.1 which form an additional background picture in synchronism with the main picture. Portions of the main picture are replaced by complementary portions of the additional image by means of a selection device (19) when the portions of the main picture have a color which is identical to the color stored in a register (7).