Abstract: A joystick actuator for controlling the positioning of objects, for instance, displays on CRTs, having a pivotally mounted control stick operatively engaging and driving a pair of optical-mask members. The optical-mask members are retained for rectilinear sliding motion relative to fixed mounted opto-switches and include spaced fins positioned to interrupt light communication within respective opto-switches. Positioning of the opto-switches and spacing of the mask fins are selected to provide successive unblocking of the interrupted light communication as the control column is displaced from neutral thereby encoding both the direction and magnitude of stick deflection.

Abstract: A video game or the like including a real-time interactive video disk game-play background generation system. The disk player incorporates track skipping capability which is under the direct control of the game processor, on a frame-by-frame basis, whereby substantially instantaneous jumps to alternative video scenes can be effected in response to changing game play. Video scene data is stored on the disk in horizontally compressed format. A video expander/scroller effectively stretches the compressed video from the disk by a factor of two and selects, under game processor control, one frame width, or one-half the expanded background scene, for display. A color programmable read-only-memory (PROM) having at least two pre-programmed color pallets is provided to redefine color relationships of game symbols stored in read-only-memory (ROM) thereby reducing the storage of redundant game symbol data in this ROM.

Abstract: A video display system is provided for a video game or the like including a computer, a CRT, and mechanism for displaying images on the CRT under control of the computer. An image memory receives image data from the computer for subsequent display on the CRT. A mechanism causes the image data to be written into the image memory in one of two selectable modes, namely, left to right or right to left. Another mechanism causes the image data to be read from the memory for subsequent display on said CRT in one of two modes, namely, top to bottom or bottom to top. A mechanism controls the selection of the writing and reading modes wherein the image displayed on the CRT may be normal or inverted when viewed from a fixed position.