Synthetic terrain generators
AssigneeTector Limited
InventorJohn Philip Adrian Race
Life of this patent
Estimating the term…
Abstract
A method and means for generating a synthetic terrain which is displayed on the screen of a cathode ray tube as a simulated landscape visible to an observer, and for use in conjunction with a vehicle simulator to provide a moving perspective view of a landscape. The scanning beam of the cathode ray tube is modulated with a video signal which is representative of the visual characteristics of the landscape at a point which at any instant is defined by the intersection of the line of sight passing from the observer's eye through the instantaneous scanning point on the cathode ray tube screen with the plane of the simulated landscape.
Claims17
A method of generating a synthetic terrain which is displayed on the screen of a cathode ray tube as a simulated landscape visible to an observer, which method includes modulating the scanning beam of a rectilinear raster scanned cathode ray tube with a video signal which is representative of the visual characteristics of the landscape at a point which at any instant is defined by the intersection of the line of sight passing from the observer's eye through the instantaneous scanning point on the cathode ray tube screen with the plane of the simulated landscape, said rectilinear raster appearing to said observer as a simulated window through which he views the landscape, said method further comprising:
- generating first electrical signals representative of the instantaneous horizontal deviation angle and instantaneous vertical deviation angle of the line of sight from a predetermined reference line from the observer's eye generally parallel to and above the simulated landscape, said signals representing pure angles, and being of different frequency and being generated from ramp signals derived from the vertical and horizontal scanning signals producing said rectilinear raster,
- generating from said vertical deviation angle signal a distance signal representative of the distance between a point on the simulated landscape defined by the vertical projection of the observer onto said simulated landscape and the intersection of the observer's line of sight with said simulated landscape,
- generating further electrical signals from said first electrical signals and said distance signal, said further signals being representative of vectors defining said intersection of the observer's line of sight with the simulated landscape, in a two coordinate system,
- generating signals defining features on said terrain,
- detecting coincidence in amplitude between the signals representing said intersection and said features, and
- modulating the scanning beam of said cathode ray tube with video signals indicative of said coincidence.
A synthetic terrain generator for generating a video signal which can be displayed on the screen of a rectilinear raster scanned cathode ray tube as a simulated landscape visible to an observer, said generator comprising circuit means for producing a video signal which is representative of the visual characteristics of the landscape at a point which at any instant is defined by the intersection of the line of sight passing from the observer's eye through the instantaneous scanning point on the cathode ray tube screen with the plane of the simulated landscape, said rectilinear raster appearing to said observer as s simulated window through which he views said landscape, said circuit means comprising:
- means for generating first electrical signals representative of the instantaneous deviation angles, in two planes of a coordinate system, of said line of sight from and with respect to a reference line from the observer's eye generally parallel to and above the simulated landscape, said signals representing pure angles and being of different frequency and being generated from ramp signals derived from the vertical and horizontal scanning signals producing said rectilinear raster,
- means for generating from said deviation angle signals, and a height above the simulated landscape of the observer's eye signal electrical signals representative of component vectors in one plane to define the intersection of said line of sight with said simulated landscape,
- means to generate signals defining features on said terrain,
- means to detect coincidence in amplitude between the signals representing said intersection and said features, and
- means to modulate the scanning beam of said cathode ray tube with video signals indicative of said coincidence.
Dependencies are inferred from the claim text.