Method and apparatus for generating moving objects on a video display screen

• US 4,112,422 A
• Filed: 12/13/1976
• Issued: 09/05/1978
• Est. Priority Date: 12/13/1976
• Status: Expired due to Term

• Current Assignee: Atari Holdings Incorporated
• Original Assignee: Atari Incorporated (Infogrames Entertainment SA)
• Inventors: Mayer, Steven T., Milner, Ronald E.
• Primary Examiner(s): Curtis, Marshall M.
• Application Number:
  US05/749,725
• Time in Patent Office: 631 Days
• Field of Search: 273/102.2 R, 273/102.2 B, 273/DIG. 28, 273/85 R, 340/324 AD, 340/337, 358/93, 358/133, 358/138, 364/900 MS File, 364/200 MS File
• US Class Current: 345/682
• CPC Class Codes: A63F 13/00 Video games, i.e. games using an electronically generated display having two or more dimensions gaming systems which provide a financial reward G07F17/32
• CPC Class Codes: A63F 13/55 Controlling game characters or game objects based on the game progress
• CPC Class Codes: A63F 2300/203 Image generating hardware
• CPC Class Codes: G06T 13/00 Animation

Abstract

A method and apparatus for generating moving objects for a video game display. Common apparatus including a microprocessor with RAM provides vertical motion for all objects and separate horizontal position counting hardware horizontal motion for each object. The microprocessor operating on a horizontal line pair basis drives a parallel to serial converter which stores one eight bit line portion of the object to be displayed which in turn is connected to a shift register. When the converted data is read out to the video display by action of the appropriate horizontal position hardware, it is recirculated to provide a repeat on the next horizontal line of the identical data. An effective one line moving resolution is obtained by utilizing another shift register for a one line delay by means of a switch which is set by a latch driven by the microprocessor.

Claims

1. A method of generating an object on a video display screen scanned in successive frames by an image forming beam traversing the screen along a plurality of horizontal lines in response to horizontal and vertical synchronizing signals and where a microprocessor has stored in its associated memory graphics data said method comprising the following steps:

sensing the current vertical position of said scan and the desired vertical object position and storing a plurality of data bits, representing said graphics data, in a first memory under control of said microprocessor if an object is to be displayed;

one horizontal line later shifting said data to a second memory while recirculating such data back into said first memory;

sensing the horizontal window of said horizontal line where said data is to be displayed and causing said data from one of said first and second memories to be displayed on said screen in response to the vertical object position starting on the first or second line of a horizontal line pair; and

in response to the next horizontal line repeating the display of the data in the previous line.

2. A method as in claim 1 including the step of timing the processing of said microprocessor in response to a horizontal sync signal.

3. A method as in claim 1 where said first memory also converts parallel data bits from said microprocessor into a serial format.

4. A method as in claim 1 where said plurality of stored data bits is equivalent to the horizontal length of an object displayed.

5. A method as in claim 1 where the processing time required by said microprocessor is always more than one horizontal line time but less than two.

6. A method as in claim 1 where in the horizontal blanking interval after the end of a line pair new data is stored in said first memory.

7. A method of generating an object on a video display screen scanned in successive frames by an image forming beam trasversing the screen along a plurality of horizontal lines in response to horizontal and vertical synchronizing signals and where a microprocessor has stored in its associated memory graphics data for said plurality of horizontal lines, said method comprising the following steps:

sensing the current vertical position of a line pair and the desired vertical object position and storing a plurality of data bits, representing said graphics data, in a memory under control of said microprocessor if an object is to be displayed at such position;

sensing whether said object is to be displayed in the first or second line of said pair; and

sensing the horizontal window of said horizontal line pair where said data is to be displayed and causing said data from said memory to be immediately displayed on said screen in response to the vertical object position starting on the first line of a horizontal line pair or delaying such display one line if the display position starts on the second line; and

repeating the display of the data in the previous line.

8. Apparatus for generating a plurality of moving objects on a video display screen scanned in successive frames by an image forming beam traversing the screen along a plurality of horizontal lines in response to horizontal and vertical synchronizing signals and where manual control inputs are provided for a plurality of game players said control inputs determining the motion of said objects said apparatus comprising:

random access memory means for storing data indicative of the vertical positions at which the objects are to be displayed on said screen as determined by said control inputs;

a plurality of horizontal position means each corresponding to one of said plurality of objects for storing data indicative of the horizontal position of the corresponding object and responsive to said control inputs for changing said position;

video adder means;

a plurality of horizontal storage register means connected to said video adder means each corresponding to one of said plurality of objects for storing graphics data in response to the actual vertical position of said beam coming within range of said stored vertical position and responsive to an output signal from a horizontal position means corresponding to such objects for transferring said graphics data to said video adder means.

9. Apparatus as in claim 8 together with a microprocessor where said horizontal position means is connected to and controlled by said microprocessor.