Lecture 3/3

OpenGL: Lighting

Download.

Please download gl.cpp for today's lecture, and create a new Visual C++ .Net project for it.

Programming

• Lighting: The Geometry

  A vertex is specified with something like,

     glVertex3f(1.,1,1)
  

  and the position is under a series of transformation, and the final position is projected.

  The position of the first character in a character series is specified by something like,

     glRasterPos3f(1, 0, 0);
  

  and again, the character position (in 3D space) goes under a series of transformation, and the final position is projected.

  Now, the position of a light source is specified by something like,

     GLfloat position[] = { 3.0, .0, .0, 1.0 };
     glLightfv(GL_LIGHT0, GL_POSITION, position);
  

  and it also goes under a series of transformation, and the final position of the light source is used for lighting computation, but NOT projected.

• Lighting: The Physics

  Three types light computation:

  • diffuse lighting
  • specular lighting
  • ambient lighting

  You also have to specify the color of both the lighting source and the object material.

• Homework: Interactively Transform Your Model With Lighting

  Continue yesterday's homework but with lighting enable. Submit your source code to zh2001 AT columbia DOT edu, cc copy xchen AT cs DOT utah DOT edu, before the end of the afternoon class.

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