1. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Chapter 15: Working with the Camera

2. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 This Chapter: we will learn about One example of implementing Computer Graphics Camera Working with multiple Cameras Examples of interactive camera manipulation Select primitive in 3D scenes

3. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Changes to Library: 2D to 3D No changes: Primitive: 2D primitives drawn in 3D SceneNode: continue to load M W Matrix Model: continue to be application main class Changes: WindowHandler When loading matrices!

4. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 WindowHandler: 2D vs 3D

5. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Lib14: Support for 3D New classes: Camera PrimitiveAxisFrame: Drawing x,y,z axis frame Modifications: WindowHandler Support Camera Load View and Projection Matrices XformInfo Support 3D rotation

6. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Lib14: New Classes and Changes

7. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Lib14: The Camera Class

8. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Lib14: WindowHandler changes

9. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Lib14: XformInfo Changes Xform Operator in 2D Scale, Translate, Pivot: all 3D quantity Problem: Rotation: θ rotates wrt to z-axis! Xform Operator in 3D (for now) Rotation: (θ x θ y θ z ) Three rotations with respect to each axes

10. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Lib14: XformInfo details … Xform Operator:

11. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Tut 15.1: Working with Lib14 Using: Camera and WindowHandler

12. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Tut 15.1: WindowHandler details

13. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Lib14: D3D_WindowHandler

14. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Tut 15.1: DrawHandler

15. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Tut 15.1: Application CTutorialDlg

16. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Tut 15.2: Working with 2 Cameras CTutorialDlg class

17. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Interactive Manipulation of Camera Parameters under explicit user control Camera position Look at position Parameters implicitly controlled Up Vector: try to maintain sense of “up” Parameters typically not controlled Near/Far planes (no real-world correspondence) FOV – zooming control via camera position movement

18. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Notation and Terminology

19. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Tut 15.3: Camera Manipulation with the Mouse Left Mouse Button (LMB) Orbit Middle (MMB) Pan Right (RMB) Zoom

20. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 LMB: Tumble or Orbit the Camera

21. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Left/Right Orbiting Axis of rotation: The “Up” Direction

22. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Up/Down Orbiting Axis or rotation: Side Vector

23. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Orbit: Idea Orbit or Rotate Need Matrix: Camera Position:

24. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Orbit: Alternatively

25. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Orbit: Implementation Rotate the World when compute M V Instead of: Compute: Compute and load:

26. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Lib14: Orbit Support Camera: mouse movement to radians And … using in WindowHandler

27. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Lib14: Using camera orbit info In WindowHandler:: ComputeViewMatrix

28. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 MMB: Pan or Track the camera

29. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Vertical Tracking: (Along UpVector)

30. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Tracking: Implementation Horizontal/Vertical mouse movements dx and dy Computer Movement vector: Left/Right tracking: along side-vector Up/down tracking: along up-vector Update both camera and at positions:

31. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Lib14: Tracking Support Camera Class:

32. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 RMB: Dolly or Zoom the Camera

33. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Zoom: Implementation Mouse movement: d Move camera eye position in the viewing direction! Watch out!

34. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Lib14: Mouse Zoom support Camera class

35. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Drawing the Camera Requires at least two Views! View-A cannot draw the camera of View-A! Can only draw the camera for another view! i.e., View-A draws camera of View-B

36. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Drawing camera: View Matrix Details Recall: for “orbiting”, we computed and loaded M V with: To properly draw camera-B, from view-A Include camera-B orbiting! Un-do view-A’s camera orbiting ( )

37. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Implementation: Load into the WORLD matrix

38. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 3D DC to WC Transformation Must: DC  NDC  EC  WC

39. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Transform: DC to NDC Assume Recall: Or: In 3D:

40. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 DC Points and NDC Ray

41. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 NDC Ray to EC Ray Transform

42. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 NDC  EC If: In general: or: Given: Then:

43. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Reconstruct the ray in EC: Given: In general, NDC Point: is a line in EC: Or:

44. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 EC to WC Transform: Given: Choose convenient z e values z e = 0 and z e = 1 Use to compute WC positions:

45. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Tut 15.4: Mouse Click to WC Shift-LMB to see the selection ray

46. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 15 Tut 15.4: Device to WC Xform