[racket-dev] [plt] Push #28945: master branch updated

On Fri, Jun 27, 2014 at 2:23 PM, Matthew Flatt <mflatt at cs.utah.edu> wrote:
> At Fri, 27 Jun 2014 13:43:46 -0400, Sam Tobin-Hochstadt wrote:
>> On Fri, Jun 27, 2014 at 12:30 PM, Matthew Flatt <mflatt at cs.utah.edu> wrote:
>> > At Fri, 27 Jun 2014 11:56:39 -0400, Sam Tobin-Hochstadt wrote:
>> >> On Fri, Jun 27, 2014 at 11:45 AM, Matthew Flatt <mflatt at cs.utah.edu> wrote:
>> >> > For some reason, the way that PDF fragments are pulled in by `pdflatex`
>> >> > makes the fragments look worse in some PDF viewers/machines than the
>> >> > way that PS fragments are pulled in by `latex` plus `dvips`. I think it
>> >> > has to do with heuristics in PDF viewers, and I think there's no
>> >> > difference when going to a printer.
>> >>
>> >> My impression was that PDF was supposed to be a pixel-accurate format,
>> >> at least when self-contained and not using system fonts, and thus
>> >> there wouldn't be any such heuristics. Is that not true?
>> >
>> > PDF is a vector-graphics format, not a raster-graphics format (so it
>> > doesn't really say anything about pixels).
>>
>> Right -- what I meant was that at a given size, rendering should be
>> pixel-accurate, so that you shouldn't see differences between
>> different viewers (unlike, say, HTML, which doesn't prescribe layout
>> nearly as precisely).
>
> Maybe the alignment problem (now fixed) in Robby's example obscured the
> issue. It's just about the smoothness of the rendering.
>
> That is, PDF specifies exactly where things should be on a cartesian
> plane, but renderers draw the same image with different pixels
> depending on the display resolution, how much time the renderer spends
> on anti-aliasing, and so on. The "look worse" part above was meant only
> about the appearance of shape edges, and not about shapes being in the
> wrong location.

In the particular `e ::= ...` example, this is an issue of font
rendering, right? IOW, the shapes being drawn differently between
dvipdf and pdflatex are fonts placed in particular spots on the page.

Sam