grafx - Extensible Java Graphics Package Code

Adding a line with 2 pixels at start major and 2 at end major, and pasting the
expected program output. We're ready to edit the line-drawing code.

Correcting some comments in code, very slightly.

Fixing a comment.

Exposing zIndex() and using that inside of setPix() and setPixCust().

Adding huge comment explaining colors and degenerate lines.

Implementing and using drawSinglePixelConstantColorLine().

Defining and using drawSinglePixelColorInterpolatedLine().

Tidying up some line-drawing issues in 3D rendering library. Still need to
handle the cases of degenerate lines, where only one pixel gets turned on, and
also need to handle the optimization of line-drawing, where the endpoints pairs
are given special attention w.r.t. z and color bounds, and the inner pixels
are rendered faster.

Adding some comments to RasterFloatGraphics.

Besides modification of some comments, revising pixel() slightly to keep
functionality the same but having the code match code in alias() more closely.