player sprites will retain the same precision they had when they were
rendered as part of the 3D view. (needed for propery alignment of flashes
on top of weapon sprites) It worked just fine for D3D, but software
rendering was another matter. I consequently did battle with imprecisions
in the whole masked texture drawing routines that had previously been
partially masked by only drawing on whole pixel boundaries. Particularly,
the tops of posts are calculated by multiplying by spryscale, and the
texture mapping coordinates are calculated by multiplying by dc_iscale
(where dc_iscale = 1 / spryscale). Since these are both 16.16 fixed point
values, there is a significant variance. For best results, the drawing
routines should only use one of these values, but that would mean
introducing division into the inner loop. If the division removed the
necessity for the fudge code in R_DrawMaskedColumn(), would it be worth it?
Or would the divide be slower than the fudging? Or would I be better off
doing it like Build and using transparent pixel checks instead, not
bothering with skipping transparent areas? For now, I chop off the
fractional part of the top coordinate for software drawing, since it was
the easiest thing to do (even if it wasn't the most correct thing to do).
SVN r1955 (trunk)
4ebfdac887
