Re: pdfcairo terminal; seams between bars in the colorbox

[Dima K. <gn...@di...>]

Oh, and two more notes, where the old code had off-by-one errors

- There old code was set up to overlap each colorbox by extending the
  bottom/right edge of each slice: GPMIN(xy_to,xy2+1)

  But that logic applies to all the slices, even the last one. This
  resulted in the last slice being one unit out-of-bounds

- The old code was computing the colors for each slice like this:

    for (i = 0; i < steps; i++)
      gray = i / (double)steps;

  This is another off-by-one error. The colors in the colorbox spanned
  [0,1-1/steps] instead of [0,1]. My patch fixes this one.

  There's some funky logic in quanize_gray() that maybe is trying to
  deal with this in the limited-max-colors case, but it's not commented,
  and applies to only this case. Code:

    qgray = floor(gray * sm_palette.use_maxcolors)
		        / (sm_palette.use_maxcolors-1);

  That should be made unnecessary