Updating graphical objects based on object validity periods

• US 5,841,439 A
• Filed: 04/24/1997
• Issued: 11/24/1998
• Est. Priority Date: 07/22/1994
• Status: Expired due to Term

• Current Assignee: Monash University
• Original Assignee: Monash University
• Inventors: Pose, Ronald David, Regan, Matthew James
• Primary Examiner(s): Nguyen, Phu K.
• Assistant Examiner(s): BUCHEL JR, RUDOLPH JOHN
• Application Number:
  US08/847,567
• Time in Patent Office: 579 Days
• Field of Search: 345/418-9, 345/421-22, 345/433, 345/436, 345/441, 345/112-114, 345/520, 345/189-91, 345/201
• US Class Current: 345/418
• CPC Class Codes: G05B 2219/32014 Augmented reality assists operator in maintenance, repair, programming, assembly, use of head mounted display with 2-D 3-D display and voice feedback, voice and gesture command
• CPC Class Codes: G06T 15/005 General purpose rendering architectures

Abstract

A graphic display system includes a set of rendering engines and a plurality of data storage units. Each data storage unit in the set of data storage units is coupled to at least one rendering engine in the set of rendering engines. A selection means is included in the graphic display system for selecting a data storage unit in the plurality of data storage units. The selected data storage unit is to be used for storing data representing an object to be displayed by the graphic display system and is selected based on a validity period of the object. The selection means includes means for determining a size validity period of the object and means for determining a translational validity period of the object. The translational validity period is a time required for the object to change by a predetermined translational threshold, wherein the predetermined translational threshold is a first angle extending from a line that passes through both a reference point and the object. The size validity period is a time required for the object to change by a predetermined size threshold, wherein the predetermined size threshold is a second angle extending from the line.

Claims

1. A graphic display system comprising:

a set of rendering engines;

a plurality of data storage units, wherein each data storage unit in said set of data storage units is coupled to at least one rendering engine in said set of rendering engines; and

a selection means for selecting a data storage unit in said plurality of data storage units, wherein said selected data storage unit is to be used for storing data representing an object to be displayed by said graphic display system and said selected data storage unit is selected based on a validity period of the object,

wherein said selection means includes means for determining the validity period of the object, said means for determining the validity period of the object including;

means for determining a size validity period of the object, and

means for determining a translational validity period of the object according to the following equation;

##EQU5## wherein the translational validity period is a time required for the object to change by a predetermined translational threshold, wherein said predetermined translational threshold is a first angle extending from a line, wherein the line passes through both a reference point and the object, wherein;

τ

_trans is the translational validity period,

distance is a length of a portion of the line, wherein the portion extends from the reference point to a center of the object,

relative speed is a speed of the object relative to the reference point, and

θ

₁ is the predetermined translational threshold.

2. The graphic display system of claim 1, wherein each data storage unit in said plurality of data storage units has an update rate that is either equal to or a harmonic of a predefined update rate.

3. The graphic display system of claim 1, wherein said selected data storage unit has an update period that is less than or equal to the validity period.

4. The graphic display system of claim 1, wherein the predetermined translational threshold is equal to a pixel spacing.

5. The graphic display system of claim 1, wherein the size validity period is a time required for the object to change by a predetermined size threshold, wherein the predetermined size threshold is a second angle extending from the line.

6. The graphic display system of claim 5, wherein said means for determining the size validity period includes:

means for calculating the size validity period, according to the following equation;

##EQU6## wherein;

τ

_size is the size validity period,

radius is a length extending from the center of the object to a perimeter of a bounding sphere for the object, and

θ

₂ is the predetermined size threshold.

7. The graphic display system of claim 6, wherein the predetermined size threshold is equal to a pixel spacing.

8. The graphic display system of claim 6, wherein the radius extends from the center of the object to an outer periphery of the object.

9. The graphic display system of claim 6, wherein the object has an animation validity period, and wherein said means for determining said validity period of the object includes:

means for selecting a smallest one of the translational validity period, the size validity period, and the animation validity period to be the validity period.

10. A method implemented by a graphical display system for rendering an object in at least one of a plurality of data storage units in said graphical display system, said method comprising the steps of:

(a) determining a validity period of the object;

(b) selecting a data storage unit in the plurality of data storage units based on the validity period; and

(c) rendering the object in the data storage unit selected in said step (b),

wherein said step (a) includes the steps of;

determining a size validity period of the object, and

calculating a translational validity period of the object according to the following equation;

##EQU7## wherein the translational validity period is a time required for the object to change by a predetermined translational threshold, wherein the predetermined translational threshold is a first angle extending from a line, wherein the line passes through both a reference point and the object, wherein;

τ

_trans is the translational validity period,

distance is a length of a portion of the line, wherein the portion extends from the reference point to a center of the object,

relative_-- speed is a speed of the object relative to the reference point, and

θ

₁ is the predefined translational threshold.

11. The method of claim 10, wherein the data storage unit has an update period that is less than or equal to the validity period.

12. The method of claim 10 wherein the predetermined translational threshold is equal to a pixel spacing.

13. The method of claim 10, wherein the size validity period is a time required for the object to change by a predetermined size threshold, wherein the predetermined size threshold is a second angle extending from a line, wherein the line passes through a reference point and the object.

14. The method of claim 13, wherein said step of determining the size validity period of the object includes the step of:

calculating the size validity period, according to the following equation;

##EQU8## wherein;

τ

_size is the size validity period,

distance is a length of a portion of the line, wherein the portion extends from the reference point to a center of the object,

relative_-- speed is a speed of the object relative to the reference point,

radius is a length extending from the center of the object to a perimeter of a bounding sphere for the object, and

θ

₂ is the predetermined size threshold.

15. The method of claim 14, wherein the predetermined size threshold is a pixel spacing.

16. The method of claim 14, wherein the radius extends from the center of the object to an outer periphery of the object.

17. The method of claim 10, wherein the object has an animation validity period and wherein said step (a) further includes the step of:

selecting a smallest one of the translational validity period, the size validity period, and the animation validity period to be the validity period of the object.

18. A method for determining a validity period for an object to be rendered by a graphic display system, wherein the object has an animation validity period, said method comprising the steps of:

calculating a translational validity period of the object according to the following equation;

##EQU9## wherein the translational validity period is a time required for the object to change by a predetermined translational threshold and the predetermined translational threshold is a first angle extending from a line passing through both a reference point and the object, wherein;

τ

_trans is the translational validity period,

distance is a length of a portion of the line, wherein the portion extends from the reference point to a center of the object,

relative_-- speed is a speed of the object relative to the reference point; and

θ

₁ is the predetermined translational threshold;

determining a size validity period of the object according to the following equation;

##EQU10## wherein the size validity period is a time required for the object to change by a predetermined size threshold and the predetermined size threshold is a second angle extending from the line, wherein;

τ

_size is the size validity period,

radius is a length extending from the center of the object to a perimeter of a bounding sphere for the object, and

θ

₂ is the predetermined size threshold; and

selecting a smallest one of the translational validity period, the size validity period, and the animation validity period to be the validity period of the object.

19. The method of claim 18, wherein the radius extends from the center of the object to an outer periphery of the object.

20. The method of claim 18 wherein the predetermined translational threshold is equal to the predetermined size threshold.

21. The method of claim 20, wherein the predetermined size threshold is equal to a pixel spacing.

22. A method implemented by a graphical display system for rendering an object in at least one of a plurality of data storage units in said graphical display system, said method comprising the steps of:

(a) determining a validity period of the object;

(b) selecting a data storage unit in the plurality of data storage units based on the validity period; and

(c) rendering the object in the data storage unit selected in said step (b),

wherein said step (a) includes the steps of;

determining a translational validity period of the object, and

calculating a size validity period of the object according to the following equation;

##EQU11## wherein the size validity period is a time required for the object to change by a predetermined size threshold, wherein the predetermined size threshold is a second angle extending from a line, wherein the line passes through a reference point and the object, wherein;

τ

_size is the size validity period,

distance is a length of a portion of the line, wherein the portion extends from the reference point to a center of the object,

relative_-- speed is a speed of the object relative to the reference point,

radius is a length extending from the center of the object to a perimeter of a bounding sphere for the object, and

θ

₂ is the predetermined size threshold.

23. The method of claim 22, wherein the translational validity period is a time required for the object to change by a predetermined translational threshold, wherein the predetermined translational threshold is a first angle extending from a line, wherein the line passes through both a reference point and the object.

24. Th method of claim 23, wherein said step of determining the translational validity period of the object includes the step of:

calculating the translational validity period, according to the following equation;

##EQU12## wherein;

τ

_trans is the translational validity period,

distance is a length of a portion of the line, wherein the portion extends from the reference point to a center of the object,

relative_-- speed is a speed of the object relative to the reference point, and

θ

₁ is the predefined translational threshold.

25. The method of claim 22, wherein the radius extends from the center of the object to an outer periphery of the object.

26. The method of claim 22, wherein the object has an animation validity period and wherein said step (a) further includes the step of:

selecting a smallest one of the translational validity period, the size validity period, and the animation validity period to be the validity period of the object.