How to Draw a Line at Non Integer Pixel Coordinates on an Image I have lines (or segments really) I want to draw into a new image I.
Let's define the intensity of the pixel at row = r and col = c as I(r,c).  However, the lines are defined by 2 points whose coordinates are not integers.

For example, one line might be from point A (with row = 2.2 and col = 3.5) and to point B with (row = 10.8 and col = 30.4).

What is the algorithm or method for filling in the intensity values of image I at the integer rows and cols?
A long time ago I wrote an article on drawing lines with the Wu-Line algorithm. This can be used to draw lines from non-integer coordinates. The effect is very nice to see when animated. You can still find it in the Wayback Machine:



Wu Anti-aliased Lines from The good-looking textured light-sourced bouncy fun smart and stretchy page

There's also some pseudo-code to get you started.