Application Programming Interfaces

Application Programming Interfaces (APIs)

provide access to rendering hardware:

X:

2D rasterization.

PostScript:

2D transformations, 2D rasterization

Phigs+, GL, OpenGL, Direct3D:

3D pipeline

APIs hide which parts are implemented in hardware by simulating missing pieces in software.

For 3D interactive applications, we might modify the scene or a model directly or just the viewing information.

After each modification, usually the image needs to be regenerated.

We need to interface to input devices in asynchronous and device independent fashion. APIs also defined for this task; we will be using X11 through Tcl/Tk.