#45 Slight graph rendering difference with/wo Cairo (4.2.4-rc1)
I installed the new rc1 build (on Windows7) and I was playing with the new "Render with Cairo" option.
I did 2 PDF exports of the same GLE script, one without Cairo and the other with, and I noticed a slight, but visually noticeable (when displaying the pdf full screen at least), rendering difference.
The attached pdf includes both renderings, the first page is the "non-cairo" version, the second page is the "cairo" version. If you display this pdf full screen (e.g. with Acrobat) and then go back and forth between page 1 and 2 you should see the difference.
I guess this can be considered a bug, yet maybe not a very urgent one.
BUT, what I would like to know as soon as possible, is which version is (most) correct? (i.e. which exported pdf should I use in my publications)
I guess there are two options:
- either there was always some rendering in accuracy in the non-cairo mode, which is not there in cairo; in which case I would go with the cairo version
- or there is an accuracy issue in the cairo renderer which the original did not have; in which case I would go for the non-cairo version
(a third possibility is of course that both renderers have their own intrinsic rendering quirks, in which case it may be hard to say which one is "most correct")
If possible, please tell me which one it is :-)
Cheers,
Matthias
PDF containing a non-cairo rendering (page 1) and a cairo rendering (page 2) of the same GLE script
Typo: "rendering in accuracy" should of course be "rendering inaccuracy"
Dear Matthias,
The original GLE rendering is the correct one.
The problem is the marker "dot", which GLE takes from a font PostScript font that is not available when using Cairo. GLE fallsback to texcmr, but the position of the dot in this font is slightly different.
Can you replace your marker with "fcircle"? This should yield identical and correct output in both versions.
Can you let me know if this helps?
Best Regards,
Jan
I'm sorry about the late response (super busy week), but your suggestion works: when using "fcircle" instead of "dot" I no longer see any difference between the original GLE rendering and the Cairo rendering. Also I noticed the filesizes of the exported PDF are much closer to each other when using "fcircle" instead of "dot".
Thanks!
I did have to play with the msize parameter a bit to get the "fcircle"s at the same size of the "dot"s. At 0.18 the fcircles and the dots (without msize) appeared to have the same size.
Regards,
Matthias
fcricle msize 0.18 (cairo)
fcricle msize 0.18 (non cairo)
Marker "dot" and most other markers are now the same with or without using Cairo. Most have been converted to using the GLEMARK font, which is available in both cases.