Pre-Midterm Course Review

• Vectors, dot products, cross products, and vector equations
• Overall structure of an OpenGL/GLUT program
• glutInit, glutCreateWindow, glutDisplayFunc, glutMainLoop
• Rendering in an OpenGL/GLUT program
• glClearColor, glClear, glBegin, glVertex3f, glEnd, glutSwapBuffers
• Programmable graphics hardware
• glewInit, glUseProgramObjectARB, glUniform3fvARB, glGetUniformLocationARB
• Camera setup and field-of-view
• Camera orientation control via mouse
• General coordinate system setup
  
• glMatrixMode, glLoadIdentity, gluPerspective, gluLookAt
• glTranslatef, glScalef, glMultMatrixf
• Diffuse and specular lighting
• Procedural texturing: computing  color from  location via an equation
  
• 2D textures, texture coordinates
• glGenTextures, glActiveTexture, glBindTexture, glTexImage2D
  
• Texture wrapping and clamping
• glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_CLAMP_TO_EDGE);
• glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
• glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_CLAMP);
• Nearest-neighbor, linear filtering, mipmapping, and anisotropic filtering
• glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST);
  
• glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
• glTexParameteri(GL_TEXTURE_2D,GL_GENERATE_MIPMAP_SGIS, GL_TRUE);
• glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_LINEAR);
  
• glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
• glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAX_ANISOTROPY_EXT,32);
• Multiple texture layers: reflected, refracted, etc
  
• Volume rendering: stepping through a 3D texture, summing up image brightness
  
• Copying rendered data back to a texture for further processing: blurring, shadowing, fractals, etc
  
• The depth buffer
• Shadow maps
  
• Alpha blending, and using alpha blending to antialias object edges
• glEnable(GL_BLEND);
  glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
  
• Raytracing planes, spheres, and arbitrary objects
• Recursive raytracing (for shadows and reflections)
  

• Builtin functions like dot, cross, length, fract, clamp, min, max, step, etc.
• uniform float overallBrightness;
• uniform vec3 cameraLoc;
• uniform mat4 shadowMat;
• uniform sampler2D myTex; ...  vec4 c = texture2D(myTex,vec2(worldCoords));
  
• varying vec3 worldCoords; ... worldCoords = vec3(gl_ModelViewMatrix * gl_Position);
  
• varying vec3 worldNormal; ... worldNormal = gl_NormalMatrix * gl_Normal;
• When to use a "uniform" (constant for a whole block of geometry), when a "varying" (linear across each piece of geometry), and when a per-pixel value (changing quickly/nonlinearly).
• gl_FragColor = worldCoords;
• gl_FragColor = worldNormal;
• gl_FragColor = (a+d)*reflectance + vec4(s);