Articulated figure animation using virtual actuators to simulate solutions for differential equations to display more realistic movements

• US 6,184,899 B1
• Filed: 03/31/1997
• Issued: 02/06/2001
• Est. Priority Date: 03/31/1997
• Status: Expired due to Term

• Current Assignee: Activision Publishing Incorporated (Microsoft Corporation)
• Original Assignee: Treyarch Invention LLC (Microsoft Corporation)
• Inventors: Akemann, Peter
• Primary Examiner(s): Zimmerman, Mark
• Assistant Examiner(s): Vo, Cliff N.
• Application Number:
  US08/829,404
• Time in Patent Office: 1,408 Days
• Field of Search: 345/473, 345/474, 345/475, 345/949, 345/953
• US Class Current: 345/473
• CPC Class Codes: A63F 13/10 Control of the course of the game, e.g. start, progess, end
• CPC Class Codes: A63F 13/45 Controlling the progress of the video game
• CPC Class Codes: A63F 13/577 using determination of contact between game characters or objects, e.g. to avoid collision between virtual racing cars
• CPC Class Codes: A63F 2300/643 by determining the impact between objects, e.g. collision detection
• CPC Class Codes: A63F 2300/6607 for animating game characters, e.g. skeleton kinematics
• CPC Class Codes: A63F 2300/8029 Fighting without shooting
• CPC Class Codes: G06T 13/40 of characters, e.g. humans, animals or virtual beings
• CPC Class Codes: Y10S 345/949 Animation processing method
• CPC Class Codes: Y10S 345/953 Geometric processing

Abstract

A computer, such as a PC, includes a memory having an imaging program stored in it and a display unit, such as a raster scan CRT are all operatively connected together so that the computing unit can generate a signal that will result in an image being displayed on the display unit. The image includes a moveable figure that moves in response to inputs being provided via an input terminal, towards a set of targets. In response to the inputs from the input terminal, the computer initiates a set of actuators to move the figure wherein each actuator defines the movement in a given plane.

Claims

1. An imaging system comprising:

a computing apparatus including a memory apparatus having an imaging program stored therein, a display apparatus and an input terminal, the computing apparatus being operably connected to the input terminal and the display apparatus; and

wherein the display apparatus displays an image generated by the computing apparatus executing the program stored in the memory apparatus and including a means for generating a sequence of frames, the image includes a moveable figure having a first and second element connected together at a first union and wherein at least the second element moves in response to inputs provided by the input terminal via the computing apparatus and wherein the computing apparatus in response to an input from the input terminal includes a virtual actuator means for defining the movement in a first plane of the second element according to a first simulation of the solution for a first equation of motion for a damped oscillator, the first equation of motion defines a first change in position of the second element in the first plane of each frame of the sequence of frames and includes a first acceleration value equal to a negative first predetermined constant times a first position value representing a displacement from a target of the second element minus a second predetermined constant times a first velocity value wherein the first velocity value is defined as the rate of change in the displacement of the second element in the first plane between frames.

2. The imaging system according to claim 1 wherein the first velocity value further comprises:

the sum of the first velocity value of a previous frame plus the first acceleration value of the current frame.

3. The imaging system according to claim 2 wherein the first position value is equal the first position value of a previous frame plus the first velocity value of the current frame.

4. The imaging system according to claim 1 further including a means for generating a sequence of frames and wherein the second element has a variable length and further comprises:

a second virtual actuator means for defining the length of the second element in a ray according to the second simulation of the solution for a second equation of motion for the damped oscillator.

5. The imaging system according to claim 4 wherein the second simulation of the solution of the second equation of motion defines a second change in length of the second element in the ray of each frame of the sequence of frames and the second equation of motion includes a second acceleration value as being equal to a negative third predetermined constant times a second position value representing a displacement of the length of the second element, minus a fourth predetermined constant times a second velocity value wherein the second velocity value is defined as the rate of change in the displacement of the length of the second element along the ray between frames.

6. The imaging system according to claim 5 wherein the second velocity value further comprises:

the sum of the second velocity value of a previous frame plus the second acceleration value of the current frame.

7. The imaging system according to claim 6 wherein the second position value is equal the second position value of a previous frame plus the second velocity value of the current frame.

8. The imaging system, according to claim 5 wherein the first simulation of the solution for a first equation of motion defines a first change in position of the second element in the first plane of each frame of the sequence of frames and the first equation of motion comprises:

a first acceleration value as being equal to a minus first predetermined constant times a first position value representing a displacement from a target of the second element minus a second predetermined constant times a first velocity value wherein the first velocity value is defined as the rate of change in the displacement of the second element in the first plane between frames and wherein the first predetermined constant is equal to the third predetermined constant and the second predetermined constant is equal to the fourth predetermined constant.

9. The imaging system according to claim 4 further comprising:

a third virtual actuator means for controlling the movement of the second element at the union between the first and the second elements in a second plane according to a third simulation of the solution to a third equation of motion for the damped oscillator.

10. The imaging system according to claim 9 wherein the third simulation of the solution for the third equation of motion defines a third position of the second element in the second plane of each frame of the sequence of frames and the third equation of motion comprises:

a third acceleration value as being equal to a negative fifth predetermined constant times a third position value representing the displacement of the second element, minus a sixth predetermined constant times a third velocity value wherein the third velocity value is defined as the rate of change in displacement of the second element between frames in the second plane.

11. The imaging system according to claim 10 wherein the third velocity value further comprises:

the sum of the third velocity value of a previous frame plus the third acceleration value of the current frame.

12. The imaging system according to claim 11 wherein the third position value is equal the third position value of a previous frame plus the third velocity value of the current third frame.

13. The imaging system, according to claim 10 wherein the first predetermined constant is equal to the fifth predetermined constant and the second predetermined constant is equal to the sixth predetermined constant.

14. The imaging system according to claim 1 including a means for generating a sequence of frames and the imaging system further comprises:

a second virtual actuator means for defining the movement of the second element at the union between the first and the second elements in a second plane according to a second simulation of the solution for a second equation of motion for the damped oscillator.

15. The imaging system according to claim 14 wherein the second simulation of the solution for a second equation of motion defines a second change in displacement of the second element in the second plane of each frame of the sequence of frames and the second equation of motion includes a second acceleration value as being equal to a minus third predetermined constant times a second position value representing the displacement of the second element in the second plane, minus a fourth predetermined constant times a second velocity value wherein the second velocity value is defined as the rate of change in displacement of the first element between frames in the second plane.

16. The imaging system according to claim 15 wherein the second velocity value further comprises:

the sum of the second velocity value of a previous frame plus the second acceleration value of the current frame.

17. The imaging system according to claim 16 wherein the second position value is equal the second position value of a previous frame plus the second velocity value of the current frame.

18. The imaging system, according to claim 15 wherein the first predetermined constant is equal to the third predetermined constant and the second predetermined constant is equal to the fourth predetermined constant.

19. The imagining system according to claim 14 further comprising:

a third virtual actuator means for defining the movement of the second element at the union between the first and the second elements in a third plane according to a third simulation of the solution for a third equation of motion for the damped oscillator.

20. The imagining system according to claim 19 wherein the third simulation of the solution for a third equation of motion defines a third position of the second element in the third plane of each frame of the sequence of frames and the third equation of motion comprises:

a third acceleration value as being equal to a negative fifth predetermined constant times a third position value representing the displacement of the second element, minus a sixth predetermined constant times a third velocity value wherein the third velocity value is defined as the rate of change in displacement of the second element between frames in the third plane.

21. The imaging system according to claim 20 wherein the third velocity value further comprises:

the sum of the third velocity value of a previous frame plus the third acceleration value of the current frame.

22. The imaging system according to claim 21 wherein the third position value is equal the third position value of a previous frame plus the third velocity value of the current frame.

23. The imaging system, according to claim 20 wherein the first predetermined constant is equal to the fifth predetermined constant and the second predetermined constant is equal to the sixth predetermined constant.

24. The imagining system according to claim 14 further comprising:

a third element joined to the second element at a second union separated from the first union and including a fourth virtual actuator means for defining the movement of the second and third elements at the second union according to a fourth simulation of the solution for a fourth equation of motion for the damped oscillator.

25. The imagining system according to claim 24 wherein the fourth simulation of the solution for a fourth equation of motion defines a first change in displacement of the second and third elements in the first plane of each frame of the sequence of frames and the fourth equation of motion comprises:

a fourth acceleration value as being equal to a negative seventh predetermined constant times a fourth position value representing the displacement of the first and third elements, minus a eighth predetermined constant times a fourth velocity value wherein the fourth velocity value is defined as the rate of change in displacement of the first and third elements in the first plane between frames.

26. The imaging system according to claim 25 wherein the fourth velocity value further comprises:

the sum of the fourth velocity value of a previous frame plus the fourth acceleration value of the current frame.

27. The imaging system according to claim 26 wherein the fourth position value is equal the fourth position value of a previous frame plus the fourth velocity value of the current frame.

28. The imaging system, according to claim 25 wherein the first predetermined constant is equal to the seventh predetermined constant and the second predetermined constant is equal to the eight predetermined constant. frames in the first plane.

29. The imaging system according to claim 24 further comprising:

a fourth element joined to the third element at a third union separated from the first and second unions and a fifth virtual actuator means for defining the movement of the third union according to a fifth simulation of the solution for a fifth equation of motion for the damped oscillator.

30. The imagining system according to claim 29 wherein the fifth simulation of the solution for a fifth equation of motion further defines a position of the second, third and fourth elements in the first plane of each frame-of the sequence of frames and the fifth equation of motion comprises:

a fifth acceleration value as being equal to negative ninth predetermined constant times a fifth position value representing the displacement of the second, third and fourth elements, minus a tenth predetermined constant times a fifth velocity value wherein the fifth velocity value is defined as the rate of change in displacement of the second, third and fourth elements in relation to the first element between frames in the first plane.

31. The imaging system according to claim 30 wherein the fifth velocity value comprises:

a sum of the fifth velocity value of a previous frame and the fifth acceleration of the current frame.

32. The imaging system according to claim 31 wherein the fourth position value is equal the fourth position value of a previous frame plus the fourth velocity value of the current frame.

33. The imaging system, according to claim 30 wherein the first predetermined constant is equal to the ninth predetermined constant and the second predetermined constant is equal to the tenth predetermined constant.

34. The imagining system according to claim 29 further comprising:

a sixth virtual actuator means for defining the movement of the fourth element at the third union in the second plane according to the sixth simulation of the solution for a sixth equation of motion for the damped oscillator.

35. The imagining system according to claim 34 wherein the sixth simulation of solution for a sixth equation of motion defines a second change in displacement of the second, third and fourth elements in the second plane of each frame of the sequence of frames and the second equation of motion includes a sixth acceleration value as being equal to a negative eleventh predetermined constant times a sixth position value representing a change of displacement of the first, third and fourth elements, minus a twelfth predetermined constant times a sixth velocity value wherein the sixth velocity value is defined as the rate of change in displacement of the second, third and fourth elements between frames in the second frame.

38. The imaging system, according to claim 35 wherein the first predetermined constant is equal to the eleventh predetermined constant and the second predetermined constant is equal to the twelfth predetermined constant.

36. The imaging system according to clam 35 wherein the sixth velocity value further comprises:

the sum of the sixth velocity value of a previous frame plus the sixth acceleration value of the current frame.

37. The imaging system according to claim 36 wherein the sixth position value is equal the sixth position value of a previous frame plus the sixth velocity value of the current frame.

39. A method of generating with a computer an image having a moveable figure comprising the steps of:

displaying on a display a sequences of frames such that for each current frame there is a preceding frame with each frame illustrating the moveable figure having a first and second element connected together at a first union;

identifying a target;

advancing at least the second element towards the identified target for each frame of the sequence of frames;

wherein the step of advancing at least the second element further comprises the step of advancing at least a first virtual actuator that defines the movement of the second element according to a first simulation of the solution for a first equation of motion for the damped oscillator in a first plane between a first preceding frame and a first current frame in the sequence of frames wherein for each frame the first simulation of the first equation of motion includes a first acceleration value, a first velocity value and a first position value and the step of advancing at least the first virtual actuator includes the steps of;

simulating the solution of the first equation of motion of the damped oscillator for the first acceleration value, modifying the first velocity value according to the sum of the first velocity value of the preceding frame plus the first acceleration value of the current frame, and modifying the first position value according to the first position value of the preceding frame plus the first velocity value of the current frame.

40. The method according to claim 39 wherein the first and second elements have a first predefined boundary further comprising:

verifying that the first position value is within the first predefined boundary; and

adjusting the first position value when the first position value is not within the predefined boundary.

41. The method according to claim 40 wherein the step of adjusting the first position value further comprises:

applying an impulse to the first element.

42. The method of generating an image according to claim 39 further comprising the steps of:

advancing a second virtual actuator wherein the second virtual actuator defines the movement in a second plane of the second element according to a second simulation of the solution for a second equation of motion for the damped oscillator.

43. The method according to claim 42 wherein for each frame the second simulation of the solution for a second equation of motion includes a second acceleration value, a second velocity value and a second position value and the step of advancing the second virtual actuator includes the steps of:

simulating the solution of the second equation of motion of the damped oscillator for the second acceleration value;

modifying the second velocity value according to the sum of the second velocity value of the preceding frame plus the second acceleration value of the current frame; and

modifying the second position value according to the second position value of the preceding frame plus the second velocity value of the current frame.

44. The method according to claim 43 wherein the first and the second elements have a second predefined boundary further comprising:

verifying that the second position value is within the second predefined boundary; and

,

adjusting the second position value when the second position value is not within the predefined boundary.

45. The method according to claim 44 wherein the step of adjusting the second position value further comprises:

applying an impulse to the first element.

46. The method of generating an image according to claim 42 further comprising the steps of:

advancing a third virtual actuator wherein the third virtual actuator defines the movement in a third plane of the second element according to a third simulation of the solution for a third equation of motion for the damped oscillator.

47. The method according to claim 46 wherein for each frame the third equation of motion includes a third acceleration value, a third velocity value and a third position value and the step of advancing the third virtual actuator includes the steps of:

simulating the solution of the third equation of motion of the damped oscillator for the third acceleration value;

modifying the third velocity value according to the sum of the third velocity value of the preceding frame plus the third acceleration value of the current frame; and

modifying the third position value according to the third position value of the preceding frame plus the third velocity value of the current frame.

48. The method according to claim 47 wherein the first and second elements have a third predefined boundary further comprising:

verifying that the third position value is within the third predefined boundary; and

,

adjusting the third position value when the third position value is not within the third predefined boundary.

49. The method according to claim 48 the step of adjusting the first, second and third position values further comprises:

applying an impulse to the first element.

50. The method of generating with a computer an image according to claim 46 wherein the moveable figure further includes at least a third element connected to the second element at a second union the method comprising the steps of for each frame:

advancing the third element towards the identified target for each frame of a sequence of frames;

advancing at least a fourth virtual actuator wherein the fourth virtual actuator defines the movement along a ray between the first current frame and the first preceding frame of the third element according to a fourth simulation of the solution for a fourth equation of motion for the damped oscillator.

51. The method according to claim 50 wherein for each frame the fourth equation of motion includes a fourth acceleration value, a fourth velocity value and a fourth position value and the step of advancing the fourth virtual actuator includes the steps of:

simulating the solution of the fourth equation of motion of the damped oscillator for the fourth acceleration value;

modifying the fourth velocity value according to the sum of the fourth velocity value of the preceding frame plus the fourth acceleration value of the current frame; and

modifying the fourth position value according to the fourth position value of a the preceding frame plus the fourth velocity value of the current frame.

52. The method according to claim 51 wherein the first, second and third elements have a predefined boundary further comprising:

verifying that the fourth position value is within the predefined boundary; and

adjusting the fourth position value when the fourth position value is not within the predefined boundary.

53. The method according to claim 52 wherein the step of adjusting the fourth position value further comprises:

applying an impulse to the second element.

54. The method of generating with a computer an image according to claim 46 wherein the moveable figure further includes at least a third element connected to the second element at a second union the method comprising the steps of for each frame:

advancing the third element towards the identified target for each frame of a sequence of frames;

advancing at least a fourth virtual actuator wherein the fourth virtual actuator defines the movement in a first plane between the first current frame and the first preceding frame of the third element according to a fourth simulation of the solution for a fourth equation of motion for the damped oscillator.

55. The method according to claim 54 wherein for each frame the fourth equation of motion includes a fourth acceleration value, a fourth velocity value and a fourth position value and the step of advancing the fourth virtual actuator includes the steps of:

simulating the solution of the fourth equation of motion of the damped oscillator for the fourth acceleration value;

modifying the fourth velocity value according to the sum of the fourth velocity value of the preceding frame plus the fourth acceleration value of the current frame; and

modifying the fourth position value according to the fourth position value of the preceding frame plus the fourth velocity value of the current frame.

56. The method according to claim 55 wherein the first, second and third elements have a predefined boundary further comprising:

verifying that the fourth position value is within the fourth predefined boundary; and

,

adjusting the fourth position value when the fourth position value is not within the predefined boundary.

57. The method according to claim 56 wherein the step of adjusting the second position value further comprises:

applying an impulse to the second element.

58. The method of generating with a computer an image according to claim 54 wherein the moveable figure includes at least a fourth element connected to the third element at a third union and wherein the method comprising the steps of:

advancing the fourth element towards the identified target for each frame of a sequence of frames;

advancing a fifth virtual actuator wherein the fifth virtual actuator defines the movement in the first plane between the first current frame and the first preceding frame of the fifth element according to a fifth simulation of the solution for a fifth equation of motion for the damped oscillator.

59. The method according to claim 58 wherein for each frame the fifth equation of motion includes a fifth acceleration value, a fifth velocity value and a fifth position value and the step of advancing the fifth virtual actuator includes the steps of:

simulating the solution of the fifth equation of motion of the damped oscillator for the fifth acceleration value;

modifying the fifth velocity value according to the sum of the fifth velocity value of the preceding frame plus the fifth acceleration value of the current frame; and

modifying the fifth position value according to the fifth position value of the preceding frame plus the fifth velocity value of the current frame.

60. The method according to claim 59 wherein the first, second, third and fourth elements have a predefined boundary further comprising:

verifying the fifth position value is within the predefined boundary; and

adjusting the fifth position value when the fifth position value is not within the predefined boundary.

61. The method according to claim 60 wherein the step of adjusting the fifth position value further comprises:

applying an impulse to the third element.

62. The method of generating an image according to claim 58 further comprising the steps of:

advancing a sixth virtual actuator wherein the sixth virtual actuator defines the movement in the second plane between the first current frame and the first preceding frame of the fourth element according to a sixth simulation of the solution for a sixth equation of motion for the damped oscillator.

63. The method according to claim 62 wherein for each frame the sixth equation of motion includes a sixth acceleration value, a sixth velocity value and a sixth position value and the step of advancing the sixth virtual actuator includes the steps of:

simulating the solution of the sixth equation of motion of the damped oscillator for the sixth acceleration value;

modifying the sixth velocity value according to the sum of the sixth velocity value of the preceding frame plus the sixth acceleration value of the current frame; and

modifying the sixth position value according to the sixth position value of the preceding frame plus the sixth velocity value of the current frame.

64. The method according to claim 63 wherein the first, second, third and fourth elements have a second predefined boundary further comprising:

verifying that the sixth position value is within the predefined boundary; and

,

adjusting the sixth position value when the sixth position value is not within the predefined boundary.

65. The method according to claim 64 wherein the step of adjusting the sixth position value further comprises:

applying an impulse to the third element.

66. An apparatus for generating with a computer an image having a moveable figure having a first and second element connected together at a first union and wherein at least the second element is displayed advancing towards an identified target for each frame wherein for each current frame there is a preceding frame of a sequence of frames the apparatus comprising:

means for identifying the target; and

,

means for advancing at least a first virtual actuator wherein the first virtual actuator defines the movement in a first plane of the second element according to a first simulation of the solution for a first equation of motion for a damped oscillator and wherein for each frame the first equation of motion includes a first acceleration value, a first velocity value and a first position value 68 and the means for advancing at least the first virtual actuator includes;

means for simulating the solution of the first equation of motion of the damped oscillator for the first acceleration value, means for modifying the first velocity value according to the sum of the first velocity value of the preceding frame plus the first acceleration value of the current frame, and means for modifying the first position value according to the first position value of the preceding frame plus the first velocity value of the current frame.

67. The apparatus according to claim 66 wherein the first and second elements have a predefined boundary and the apparatus further comprising:

means for verifying that the first position value is within the first predefined boundary; and

means for adjusting the first position value when the first position value is not within the predefined boundary.

68. The apparatus according to claim 67 wherein the means for adjusting the first position value further comprises:

means for applying an impulse to the first element.

69. The apparatus for generating an image according to claim 66 further comprising:

advancing a second virtual actuator wherein the second virtual actuator defines the movement in a second plane of the second element according to a second simulation of the solution for a second equation of motion for the damped oscillator.

70. The apparatus according to claim 69 wherein for each frame the second equation of motion includes a second acceleration value, a second velocity value and a second position value and the apparatus for advancing the second virtual actuator includes:

means for simulating the solution of the second equation of motion of the damped oscillator for the second acceleration value;

means for modifying the second velocity value according to the sum of the second velocity value of the preceding frame plus the second acceleration value of the current frame; and

means for modifying the second position value according to the second position value of the preceding frame plus the second velocity value of the current frame.

71. The apparatus according to claim 70 wherein the first and the second elements have a predefined boundary further comprising:

means for verifying that the second position value is within the predefined boundary; and

,

means for adjusting the second position value when the second position value is not within the predefined boundary.

72. The apparatus according to claim 71 wherein the apparatus for adjusting the second position value further comprises:

means for applying an impulse to the first element.

73. The apparatus for generating an image according to claim 69 further comprising:

means for advancing a third virtual actuator wherein the third virtual actuator defines the movement in a third plane of the second element according to a third simulation of the solution for a third equation of motion for the damped oscillator.

74. The apparatus according to claim 73 wherein for each frame the third equation of motion includes a third acceleration value, a third velocity value and a third position value and the apparatus for advancing the third virtual actuator includes:

means for simulating the solution of the third equation of motion of the damped oscillator for the third acceleration value;

means for modifying the third velocity value according to the sum of the third velocity value of the preceding frame plus the third acceleration value of the current frame; and

means for modifying the third position value according to the third position value of the preceding frame plus the third velocity value of the current frame.

75. The apparatus according to claim 74 wherein the first and second elements have a predefined boundary further comprising:

means for verifying that the third position value is within the third predefined boundary; and

,

means for adjusting the third position value when the third position value is not within the third predefined boundary.

76. The apparatus according to claim 75 the step of adjusting the third position values further comprises:

means for applying an impulse to the first element.

77. The apparatus for generating with a computer an image according to claim 73 wherein the moveable figure further includes at least a third element connected to the second element at a second union and wherein the third element is displayed advancing towards the identified target for each frame of a sequence of frames, the apparatus comprising:

means for advancing at least a fourth virtual actuator wherein the fourth virtual actuator defines the movement of alone a ray the third element according to a fourth simulation of the solution for a fourth equation of motion for the damped oscillator.

78. The apparatus according to claim 77 wherein for each frame the fourth equation of motion includes a fourth acceleration value, a fourth velocity value and a fourth position value and the step of advancing the fourth virtual actuator includes:

means for simulating the solution of the fourth equation of motion of the damped oscillator for the fourth acceleration value;

means for modifying the fourth velocity value according to the sum of the fourth velocity value of the preceding frame plus the fourth acceleration value of the current frame; and

means for modifying the fourth position value according to the fourth position value of the preceding frame plus the fourth velocity value of the current frame.

79. The apparatus according to claim 78 wherein the first, second and third elements have a predefined boundary further comprising:

means for verifying that the fourth position value is within the predefined boundary; and

means for adjusting the fourth position value when the fourth position value is not within the predefined boundary.

80. The apparatus according to claim 79 wherein the means for adjusting the fourth position value further comprises:

means for applying an impulse to the second element.

81. The apparatus for generating an image according to claim 73 further comprising:

means for advancing a fourth virtual actuator wherein the fourth virtual actuator defines the movement in a first plane of the third element according to a fourth simulation of the solution for a fourth equation of motion for the damped oscillator.

82. The apparatus according to claim 81 wherein for each frame the fourth equation of motion includes a fourth acceleration value, a fourth velocity value and a fourth position value and means for advancing the fourth virtual actuator includes:

means for simulating the solution of the fourth equation of motion of the damped oscillator for the fourth acceleration value;

means for modifying the fourth velocity value according to the sum of the fourth velocity value of the preceding frame plus the fourth acceleration value of the current frame; and

means for modifying the fourth position value according to the fourth position value of the preceding frame plus the fourth velocity value of the current frame.

83. The apparatus according to claim 82 wherein the first, second and third elements have a predefined boundary further comprising:

means for verifying that the fourth position value is within the fourth predefined boundary; and

,

means for adjusting the fourth position value when the fourth position value is not within the predefined boundary.

84. The apparatus according to claim 83 wherein the means for adjusting the fourth position value further comprises:

means for applying an impulse to the second element.

85. The apparatus for generating with a computer an image according to claim 77 wherein the moveable figure includes a fourth element connected to the third element at a third union and wherein the fourth element is displayed advancing towards the identified target for each frame of a sequence of frames the apparatus comprising:

means for advancing a fifth virtual actuator wherein the fifth virtual actuator defines the movement in the first plane of the fifth element according to a fifth simulation of the solution for a fifth equation of motion for the damped oscillator.

86. The apparatus according to claim 85 wherein for each frame the fifth equation of motion includes a fifth acceleration value, a fifth velocity value and a fifth position value and the means for advancing the fifth virtual actuator includes:

means for simulating the solution of the fifth equation of motion of the damped oscillator for the fifth acceleration value;

means for modifying the fifth velocity value according to the sum of the fifth velocity value of the preceding frame plus the fifth acceleration value of the current frame; and

means for modifying the fifth position value according to the fifth position value of the preceding frame plus the fifth velocity value of the current frame.

87. The apparatus according to claim 86 wherein the first, second, third and fourth elements have a predefined boundary further comprising:

means for verifying the fifth position value is within the predefined boundary; and

means for adjusting the fifth position value when the fifth position value is not within the predefined boundary.

88. The apparatus according to claim 87 wherein the means for adjusting the fifth position value further comprises:

means for applying an impulse to the third element.

89. The apparatus of generating an image according to claim 88 further comprising:

means for advancing a sixth virtual actuator wherein the sixth virtual actuator defines the movement in the second plane of the fourth element according to a sixth simulation of the solution for a sixth equation of motion for the damped oscillator.

90. The apparatus according to claim 89 wherein for each frame the second equation of motion includes a sixth acceleration value, a sixth velocity value and a sixth position value and means for advancing the sixth virtual actuator includes:

means for simulating the solution of the sixth equation of motion of the damped oscillator for the sixth acceleration value;

means for modifying the sixth velocity value according to the sum of the sixth velocity value of the preceding frame plus the sixth acceleration value of the current frame; and

means for modifying the sixth position value according to the sixth position value of the preceding frame plus the sixth velocity value of the current frame.

91. The apparatus according to claim 90 wherein the first, second, third and fourth elements have a predefined boundary further comprising:

means for verifying that the sixth position value is within the predefined boundary; and

,

means for adjusting the sixth position value when the sixth position value is not within the predefined boundary.

92. The apparatus according to claim 91 wherein the means for adjusting the sixth position value further comprises:

means for applying an impulse to the third element.