Bottom margin vs. descenders question
doug at mathemaesthetics.com
Mon Jul 6 21:43:21 CEST 2020
In the screenshot that I posted, I failed to mention that the program actually adjusts the margin line(s) outwards by half the linewidth, so that the true content area within the margins is not visually covered by drawing the margin lines. The analysis of whether a margin is breached is done in a 72 pixels per inch pixmap built in memory from the PDF, but the added margin drawing and announcements are done in floating point view coordinates, which allows the nicety of moving the margin lines by half a linewidth. What this means is that in the screenshot, the parts of the descending parentheses >covered< by the thin red margin line are actually >outside< of the 7.5" x 10" content bounds. Not that it matters much, because the size of the descending parts of the parentheses are a whole lot larger.
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