1. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Chapter 3: Simple Graphics Program

2. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 We will learn Review coordinate systems Simplest drawing program Graphics API drawing procedure Abstraction of drawing with graphics API

3. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Take a photograph Paper: cut to right size Position: place at right palce

4. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Coordinate system The origin The X/Y Axes Directions Units on axes

5. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Paper: size and location

6. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Vertex Positions Order of specification: V a  V b  V c  V d Clockwise vs Counterclockwise Either is ok, but consistent ! Choice of origin Convenience!

7. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Tutorial 3.1: Computer graphics solution

8. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Tutorial 3.1: Frontend Main application window and Drawing Window

9. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Tutorial 3.1: Backend programming Main window (CTutorialDlg) Has an instance of drawing window At runtime: place the drawing window into the application window

10. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Tutorial 3.1: Drawing Window CGrfxWindowD3D … A MFC CWnd object Knows how to replace itself onto an application window Allows D3D drawing (OnPaint()) …

11. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 GrfxWindow: OnPaint() function Drawing … 4 steps …

12. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 GrfxWindow: Drawing …

13. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Lesson learned: Computer graphics: Draws geometry: Render Must measure and design before coding Coordinate system Choose a convenient system: Origin, and units for measurement

14. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Graphics API independent drawing

15. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Graphics objects: Rectangle

16. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Graphics objects: Circle Center: (0,0) Radius: r If center at (x c,y c ) x = x c + r sin(θ) y = y c + r cos(θ)

17. Essentials of Interactive Computer Graphics: Concepts and Implementation K. Sung, P. Shirley, S. Baer Chapter 3 Circle: implementation