Draw, Clear and Flip Operations

These are the basic graphics operations for drawing to a viewport. Each function takes a viewport as its argument and returns a function operating within that viewport. Further arguments, if any, are curried. For example, (draw-line viewport) returns a function, that can then be applied to the proper arguments to draw a line in the viewport corresponding to viewport descriptor viewport. An example follows.

Where ``draw-'' commands make pixels black, ``clear-'' commands make them white.

Where ``draw-'' commands make pixels black, a ``flip-'' commands cause them to change.

• Viewports
• Pixels
• Lines
• Rectangles
• Ellipses
• Polygons
• Strings
• Pixmaps