168 471 Computer Graphics, KKU. Lecture 10

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Introduction to OpenGL

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OpenGL/GLU/GLUT/GLUI

• OpenGL v1.4 (latest) is the “core” library that is platform independent

• GLUT v3.6 or v3.7 (beta) is an auxiliary library that handles window creation, OS system calls (mouse buttons, movement, keyboard, etc), callbacks.

• GLU is an auxiliary library that handles a variety of graphics accessory functions

• GLUI v1.0 or v2.0 (beta)is a GUI manager written by Paul Rademacher (rademach@cs.unc.edu).

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GLUT 3D Primitives

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Double Buffer

• Graphics card scans out the image on the frame buffer. What rate is this done at?

• So what is the problem with this?• You might be in the middle of drawing a frame

when it decides to scan out the image• What is a solution?• Have two separate frame buffers, one that

the card scans out of, and the other you draw into. When you are done drawing a frame, you switch their roles

• What are the memory requirements?

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Double Buffering

...

glVertex3f(0.1,0.1,0.1)

glutSwapBuffers();

...

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Double Buffering...

glVertex3f(0.1,0.1,0.1)

glutSwapBuffers();

...

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