Re: [yt-dev] Default colormap

> Hi Stuart and everyone else, > > This is great info. I appreciate everyone's thoughtful replies. > > Having both a sequential colormap (which would replace algae) and a > diverging colormap, would be awesome. The Paraview devs shipped the > new matplotlib ones (like Inferno) in 5.0. I think it would be a fun > experiment to see if we can come up with something sufficiently > "branded" or different. And then if we can't, fall back on something > like Inferno? > > -Matt > > On Wed, Jan 6, 2016 at 12:48 PM, Levy, Stuart A salevy@illinois.edu wrote: >> There was a fair bit of discussion about colormaps - terrible, useful, >> beautiful - at IEEE Vis last October. The viridis colormap was a featured >> one. So was the traditional rainbow, which lots of info-vis and perceptual >> people piled on to criticize. >> >> Among design criteria for a continuous-valued colormap is whether it's >> "sequential" (like the typical yt colormap, or viridis) or "diverging". >> You'd want a diverging colormap to show signed deviations from a norm - >> where the eye should be caught by places where a value is either much less >> than, or much more than, something in the middle. Is it worth offering a >> typical divergent colormap, as well as a new typical sequential one, in yt? >> >> Note that among the Stefan van der Walt & Nathaniel Smith writeup ( >> http://bids.github.io/colormap/ ) on their development of better cmaps, they >> use Nathan Goldbaum's galaxy evolution as a test case for six (sequential) >> examples! => http://vorpus.org/~njs/goldbaum-galaxies-all-colormaps.mkv >> >> A neat web site with sample colormaps - aimed at mapping discrete values on >> geographic maps, so not directly applicable but cool - is this, by Cynthia >> Brewer and Mark Harrower at PSU: >> http://colorbrewer2.org/ >> It has a library of predesigned cmaps, and lets you sift them by being >> colorblind-safe, photocopy safe, etc. >> ________________________________ >> From: yt-dev [yt-dev-bounces@lists.spacepope.org] on behalf of B.W. Keller >> [kellerbw@mcmaster.ca] >> Sent: Wednesday, January 06, 2016 12:13 >> To: yt-dev@lists.spacepope.org >> Subject: Re: [yt-dev] Default colormap >> >> There is a really excellent paper on designing color maps called "Color >> Sequences for Univariate Maps: Theory, Experiments, and Principles" that you >> can get here: >> http://ccom.unh.edu/sites/default/files/publications/Ware_1988_CGA_Color_seq... >> >> If we design a new colormap, this would be a good reference along with those >> scipy resources. I personally would love to have an accessible, yt-custom >> colormap. >> >> On Wed, Jan 6, 2016 at 11:50 AM, Erik Schnetter schnetter@gmail.com wrote: >>> >>> I think there are several colourmaps that were created when Viridis >>> was invented. I personally like Inferno. >>> >>> -erik >>> >>> On Wed, Jan 6, 2016 at 11:34 AM, Nathan Goldbaum nathan12343@gmail.com >>> wrote: >>>> I would also be for coming up with our own colormap. That said, I think >>>> simply modifying algae won't be enough, since it is too perceptually >>>> nonlinear. >>>> >>>> On Wed, Jan 6, 2016 at 10:32 AM, John ZuHone jzuhone@gmail.com wrote: >>>>> >>>>> I would go for modifying algae. >>>>> >>>>>> On Jan 6, 2016, at 11:30 AM, Matthew Turk matthewturk@gmail.com >>>>>> wrote: >>>>>> >>>>>> Hi folks, >>>>>> >>>>>> For a long time we've used "algae," which was designed by Britton >>>>>> about eight years ago, as the default colormap. This has been really >>>>>> nice for "branding" yt -- if you see an algae plot, it's probably >>>>>> (not >>>>>> definitely) made with yt. But it's also not accessible from a >>>>>> colorblindness perspective. Stefan van der Walt has been giving some >>>>>> really great talks lately about building a better colormap for >>>>>> matplotlib (e.g., https://www.youtube.com/watch?v=xAoljeRJ3lU ) which >>>>>> culminated in viridis, which is shipping in recent versions of >>>>>> matplotlib and will become the default. >>>>>> >>>>>> In support of this, he built a tool called viscm which can generate >>>>>> reduced versions of colormaps to show what they would be like with >>>>>> varying degrees of insensitivity to color. I've generated outputs >>>>>> from viscm of three of the custom colormaps we ship with yt: >>>>>> >>>>>> Algae: https://images.hub.yt/u/fido/m/d275d5e1-png/ >>>>>> Cubehelix: https://images.hub.yt/u/fido/m/8e698928-png/ (I believe >>>>>> this is now also shipped with MPL) >>>>>> Kamae: https://images.hub.yt/u/fido/m/e0e40efa-png/ >>>>>> >>>>>> I love algae, but it's not the best from an accessibility >>>>>> perspective. >>>>>> >>>>>> I'd like to propose that we use a new default colormap. If we do >>>>>> this, I see two options: >>>>>> >>>>>> Retain a "branding" by developing a new one either by using the >>>>>> techniques used by matplotlib (or one of the maps they opted not to >>>>>> use) or by modifying algae to be more accessible; looking at the >>>>>> response functions, I suspect it would be reasonably possible to >>>>>> modify it. (Modifying algae is my preference.) >>>>>> Use viridis (which we may then have to ship if we have older >>>>>> versions of matplotlib to support) >>>>>> >>>>>> -Matt >>>>>> _______________________________________________ >>>>>> yt-dev mailing list >>>>>> yt-dev@lists.spacepope.org >>>>>> http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org >>>>> >>>>> _______________________________________________ >>>>> yt-dev mailing list >>>>> yt-dev@lists.spacepope.org >>>>> http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org >>>> >>>> >>>> >>>> _______________________________________________ >>>> yt-dev mailing list >>>> yt-dev@lists.spacepope.org >>>> http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org >>>> >>> >>> >>> >>> -- >>> Erik Schnetter schnetter@gmail.com >>> http://www.perimeterinstitute.ca/personal/eschnetter/ >>> _______________________________________________ >>> yt-dev mailing list >>> yt-dev@lists.spacepope.org >>> http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org >> >> >> >> _______________________________________________ >> yt-dev mailing list >> yt-dev@lists.spacepope.org >> http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org >> _______________________________________________ yt-dev mailing list yt-dev@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org