Object oriented video framework system

• US 5,471,675 A
• Filed: 07/27/1993
• Issued: 11/28/1995
• Est. Priority Date: 07/27/1993
• Status: Expired due to Term

• Current Assignee: Apple Inc.
• Original Assignee: Taligent, Inc. (HP Inc.)
• Inventors: Zias, Jeff
• Primary Examiner(s): Powell, Mark R.
• Assistant Examiner(s): CHAUHAN, ULKA J
• Application Number:
  US08/097,507
• Time in Patent Office: 854 Days
• Field of Search: 395/162-166,500, 395/600
• US Class Current: 345/501
• CPC Class Codes: G06F 8/24 Object-oriented
• CPC Class Codes: G06F 8/38 for implementing user interfaces

Abstract

A video framework for use in a data processing system provides parallel hierarchies of video device drivers and video device handles, which are created by video device driver objects, and a hierarchy of data encapsulators contained by a subclass of the hierarchy of video device handles to encapsulate configuration information describing the functionality of a display device connected to a data processing system. Applications access video device drivers through ones of the video device handles at respective levels of the video device handle hierarchy. When a change of configuration is made or requested in for the data processing system or any display connected thereto, corresponding video display handles issue a signal to lock down drawing tasks before video handles are created or altered to carry out the configuration change. The video framework thus allows changes to be made in configuration of the system and/or functionality of the display devices without loss of information displayed to a user and maintains a default functionality of displays connected to the data processing system.

Claims

1. A video framework for processing graphic information, comprising:

(a) processor;

(b) a memory;

(c) a class of video device drivers having at least one subclass derived therefrom in memory;

(d) a class of video device handle objects having a subclass derived therefrom, each subclass of device handle objects corresponding to a subclass from the class of video device drivers stored in the memory; and

(e) a class of data encapsulators having at least one video device data encapsulator subclass derived therefrom, wherein the class of video device handle objects includes means for instantiating a corresponding video device data encapsulator object to be used by the processor for processing the graphic information.

2. A video framework as recited in claim 1, including:

(a) a configuration access manager class contained by the video device driver class, and

(b) a class of bus access objects contained by the configuration access manager class.

3. A video framework as recited in claim 2, including a class of objects contained by the class of bus access objects representing display devices which are connectable to a bus accessed by objects of the class of bus access objects.

4. A video framework as recited in claim 1, including means for identifying, to the processor, a video device handle object, instantiated from the class of video device handle objects.

5. A video framework as recited in claim 1, including means for recording status information.

6. A video framework as recited in claim 1, including means for reporting status changes to the processor.

7. A video framework as recited in claim 1, including means for managing a plurality of video frameworks by the processor.

8. A video framework as recited in claim 7, including means for activating a video framework.

9. A video framework as recited in claim 7, including means for deactivating a framework.

10. A method for processing graphic information in a memory of a processor, including the steps of:

(a) creating a video device driver object from a configuration access manager object in the memory under control of the processor;

(b) creating a video device handle object from the video device driver object in the memory under control of the processor;

(c) creating a video device data encapsulator object from the video device handle object in the memory;

(d) sending parameters of the video device handle object to a layer server in the memory under control of the processor; and

(e) associating the video device handle object with the video device driver object.

11. The method as recited in claim 10, including the step of sending parameters of the video device data encapsulator object to a hardware configuration server.

12. The method as recited in claim 10, including the step of identifying a video device handle object, instantiated from the class of video device handle objects to the processor.

13. The method as recited in claim 10, including the step of recording status information in the memory.

14. The method as recited in claim 10, including the step of reporting status changes to the processor.

15. The method as recited in claim 10, including the step of managing a plurality of Video frameworks by the processor.

16. The method as recited in claim 15, including means for activating a video framework.

17. The method as recited in claim 15, including means for deactivating a framework.

18. A method for processing graphic information in a memory of a processor, including the steps of:

(a) creating a video device data encapsulator object in response to detection of at least one of a configuration change of the processor;

(b) sending a parameter of the configuration change to a video device handle object which contains the video device data encapsulator object;

(c) locking drawing tasks on at least one display device in response to a signal generated by the video device handle object;

(d) changing a configuration of the processor by altering or creating a video device handle, and

(e) issuing a command to a video device handle to cause the video device handle to regenerate a display corresponding to the drawing tasks as locked, and to release the locking of the drawing tasks.

19. A video framework for allowing a client to manipulate video devices, the framework comprising:

a hierarchy of video device subclasses derived from a base video device class, each of the video device subclasses comprising a device data component and device control methods for manipulating a predetermined type of video device;

a hierarchy of video device handle subclasses derived from a base class of video device handle class, the hierarchy of video device handle subclasses including a subclass corresponding to each of the video device subclasses, each of the video device handle subclasses comprising a data component and methods for interfacing with the client;

and wherein each of the video device subclasses comprises object methods for instantiating a video device handle object from a corresponding subclass and an object method for copying at least one of the device control methods into the video device handle object.

20. The video framework of claim 19 further comprising a hierarchy of data encapsulator subclasses derived from a base data encapsulator class, each of the data encapsulator subclasses comprising a data component and methods for storing and manipulating video data and wherein at least one of the video device handle subclasses comprises object methods for instantiating a data encapsulator object from one of the data encapsulator subclasses.

21. The video framework of claim 19 wherein the framework operates within an operating system and wherein each of the video device handle subclasses comprises methods for identifying a video device handle object instantiated from the each video device handle subclass to the operating system.

22. The video framework of claim 19 wherein the hierarchy of video device handle subclasses comprises a frame buffer video device handle subclass and wherein the hierarchy of video device subclasses comprises a frame buffer video device driver subclass having a control data component and control methods for manipulating a video frame buffer and a method for instantiating a frame buffer video device handle object from the frame buffer video device handle subclass.

23. The video framework of claim 22 wherein the hierarchy of video device handle subclasses comprises a color lookup table frame buffer video device handle subclass derived from the frame buffer video device handle subclass and wherein the hierarchy of video device subclasses comprises a color lookup table frame buffer video device driver subclass derived from the frame buffer video device driver subclass, the color lookup table frame buffer video device driver subclass having a control data component and control methods for manipulating a color lookup table and a method for instantiating a color lookup table frame buffer video device handle object from the color lookup table frame buffer video device handle subclass.

24. The video framework of claim 23 further comprising an interrupt handler class and wherein the color look up table frame buffer video device driver subclass contains a reference to at least one interrupt handler object instantiated from the interrupt handler class.

25. The video framework of claim 19 wherein at least one of the video device handle subclasses includes a method for instantiating a graphics device object that provides a minimal set of graphical functions.

26. A method of using a video framework to create a video device driver hierarchy accessible to a client, the video flamework having a base video device class and a base video device handle class, the method comprising the steps of:

(a) deriving a hierarchy of video device subclasses from the base video device class such that each of the video device subclasses comprises a device data component and device control methods for manipulating a predetermined type of video device;

(b) deriving a hierarchy of video device handle subclasses from the base video device handle class to include a video device handle subclass correspond to a video device subclass, and such that each of the video device handle subclasses comprises a data component and methods for interfacing with the client; and

wherein each of the derived video device subclasses comprises object methods for instantiating a video device handle object from a corresponding video device handle subclass and further comprises an object method for copying at least one of the device control methods into the video device handle object.

27. The method of claim 26, wherein the framework further comprises a base data encapsulator class, and the method further comprises a step of:

(c) deriving a hierarchy of video device data encapsulator subclasses such that each comprises a data component and methods for storing and manipulating video data, and

wherein step (b) includes deriving at least one video device handle subclass comprising object methods for instantiating a data encapsulator object from one of the video data encapsulator subclasses.

28. The method of claim 26 wherein the framework operates within an operating system and wherein step (b) includes:

(b1) deriving each of the video device handle subclasses so as to comprise methods for identifying to the operating system a video device handle object instantiated from the each video device handle subclass.

29. The method of claim 26 wherein step (b) includes:

(b2) deriving a frame buffer video device handle subclass within the hierarchy of video device handle subclasses,

and wherein step (a) includes the step of;

(a1) deriving a frame buffer video device driver subclass within the hierarchy of video device subclasses such that the frame buffer video device driver subclass includes control data component and control methods for manipulating a video frame buffer and a method for instantiating a frame buffer video device handle object from the frame buffer video device handle subclass.

30. The method of claim 29 wherein step (b) includes the step of:

(b3) deriving a color lookup table frame buffer video device handle subclass within the hierarchy of video device handle subclasses from the frame buffer video device handle subclass, and

wherein step (a) includes the step of;

(a2) deriving a color lookup table frame buffer video device driver subclass within the hierarchy of video device subclasses from the frame buffer video device driver subclass, such that the color lookup table frame buffer video device driver subclass includes a control data component and control methods for manipulating a color lookup table and a method for instantiating a color lookup table frame buffer video device handle object from the color lookup table frame buffer video device handle subclass.

31. The method of claim 30 further comprising a step of

(d) deriving an interrupt handier class, and wherein step (a2) includes the step of:

(a2.1) deriving the color look up table frame buffer video device driver subclass to contain a reference to at least one interrupt handler object instantiated from the interrupt handler class.

32. The method of claim 26 wherein step (b) includes the step of:

(b4) deriving at least one of the video device handle subclass to include a method for instantiating a graphics device object that provides a minimal set of graphical functions.