CSE328:Computer Graphics OpenGL Tutorial

1. CSE328:Computer GraphicsOpenGL Tutorial Dongli Zhang Department of Computer Science, SBU dozhang@cs.stonybrook.edu Department of Computer Science, Stony Brook University (SUNYSB)

2. TA Information Department of Computer Science, Stony Brook University (SUNYSB) • TA Schedule: • Time: Tuesday: 4:30~6:00pm; • Location: Computer Science Building, 2110; • Email: dozhang@cs.stonybrook.edu

3. Introduction to OpenGL CSE328 What is OpenGL? • Industrial standard library for doing computer graphics. • Developed by Silicon Graphics Inc.(SGI) in 1992. • Latest version: 4.3 (released at Aug 6, 2012). • Features: • Keep developing. More functions,GLSL,64-bit support. • OpenGL is a Graphic rendering API (software interface to graphics • hardware) • consists of lots of commands. for example: GL_BEGIN(GLint TYPE) • Operating system independent. • References: • http://en.wikipedia.org/wiki/Opengl • http://www.opengl.org/

4. Introduction to OpenGL CSE328 • If you want to be a Software Engineer in Computer graphics area, • OpenGL is a MUST! • Giant Companies: NVidia, ATI(AMD),Google, Adobe, Pixar, Blizzard, • Siemens Medical…

5. Introduction to OpenGL CSE328 • Other 3D Graphics APIs: • Direct3D --- a competitor to OpenGL. • Mesa 3D --- an open source implementation of OpenGL. • Open Inventor --- C++ object oriented 3D graphics API in higher layer • of programming. • RISpec --- Pixar’s open API for photorealistic off-line rendering. • Other 2D graphics APIs: • GTK+. • Java 2D, QT

6. OpenGL programming guide CSE328 • Things you should know before coding: • OpenGL was designed be graphic output-only. • Provide rendering functions only. • Core API has no concept of windowing systems, audio, printing to • screening, keyboard/mouse or other input devices. • OpenGL need add-on APIs to interact with the host system. • GLX --- X11 • WGL --- Microsoft Windows • CGL --- Mac OS X • For convenient, people developed libraries to provide • functionality for basic windowing using OpenGL, such as GLUT. OpenGL need a GUI in window system.

7. Tools for programming: • C/C++ compiler and debugger: MS, gcc. • IDE: MS Visual studio, Dev-C++, Eclipse+cdt, Xcode, … • GUI: GLUT + GLUI, QT, MFC… • Recommendation: • VS2010 + GLUT + GLUI(QT) • Reasons: free, easy for debug. OpenGL programming guide

8. A state machine • You put OpenGL into various states that then remain in effect until you change them • State is encapsulated in contexts. Each OpenGL window has its own, separate, state. • Think of each context as a C/C++ struct with fields for each OpenGL state variable. • Generally, there are two operations that you do with OpenGL: • Draw something • Change the state of how OpenGL draws • OpenGL has two types of things that it can render: • Geometric primitives: points, lines and polygons • Image Primitives: bitmaps and graphics image • Additionally, OpenGL links images and geometric primitives together using Texture Mapping. OpenGL language

9. OpenGL language

10. OpenGL language

11. OpenGL language

12. OpenGL language

13. OpenGL language

14. OpenGL language

15. OpenGL geometric primitives

16. OpenGL geometric primitives

17. OpenGL geometric primitives

18. OpenGL geometric primitives

19. OpenGL geometric primitives

20. OpenGL geometric primitives

21. OpenGL geometric primitives

22. OpenGL geometric primitives

23. OpenGL geometric primitives

24. Rendering

25. Rendering

26. Controlling current state

27. GLUT

28. What can GLUT do? GLUT

29. GLUT programming

30. Initialization

31. Initialization

32. Open a window

33. Open a window

34. Handle Events

35. Handle Event

36. Handle events

37. GLUT

38. GLUT

39. GLUT

40. GLUT

41. GLUT

43. Enter event processing loop

44. GLUT summary

45. GLUT Menu

46. GLUT Menu

47. Put together

50. GLUI