Graphics Rendering Pipeline

• Computer graphics is generally, the representation of a 3D scene on a 2D plane.
• Traditionally accomplished using a pipeline to compose transformations from object space to screen space.
  

Object Space (3D)

• Also called modeling space
• Object of unit size centered at origin
• Model of object constructed using, typically, triangle strips
• glVertex3f(-0.25, 0, 0)

World Space (3D)

• Position, rotate, scale object in relation to other objects
• Light object
• glMatrixMode(GL_MODELVIEW)

Eye Space (3D)

• Also called normalized viewing space
• Position, rotate, scale object as seen by camera
• Clip, remove, objects not visible within camera frustrum
• glMatrixMode(GL_PROJECTION)

Viewport Space (3D)

• Also called image space
• Project objects onto camera's 2D viewport
• Clip, remove, hidden surfaces

Screen Space (2D)

• Scale object to device coordinates, based on dimensions of window on screen
• Scan convert, rasterize, object from geometry to pixels
• Color object based on capabilities of hardware
• glViewport(0, 0, theWindowWidth, theWindowHeight)

References

• Notes on 2D transforms by Steve Marschner
• Notes on 3D transforms by Steve Marschner
• Notes on 2D and 3D transforms by Pankaj Agarwal
• Notes on OpenGL Matrix Structure by Robert Cox
• The transformation game from Brown University
• Scenegraph games from Brown University