by CliffStoll on 6/18/24, 10:23 PM
In the 1970's, I had the honor of working with Bill Hartmann, Bob Strom, Gerard Kuiper, Clark Chapman and Ewen Whittaker, at Tucson's Lunar & Planetary Labs. They used large earthbased telescopes to photograph the moon's surface at many illumination angles and libation angles. The images were captured on glass plates.
They physically projected these images onto a large plaster sphere; in turn, they rephotographed the images from different angles, to remove foreshortening and show the lunar surface as seen from directly above a crater.
One result of this is the Rectified Lunar Atlas -- one of the guiding maps of the Apollo missions:
https://sic.lpl.arizona.edu/collection/rectified-lunar-atlas
by malshe on 6/18/24, 3:06 PM
Looking forward to reading this post but just wanted to say that the work Tyler has done on ray tracing in R is phenomenal. I highly recommend checking out this package website:
https://www.rayshader.comby pneumic on 6/18/24, 3:23 PM
Nice post. R's quirks seem to put some people off but I've found that it's a relative joy for exploratory analysis and visualization like this, especially within RStudio.
Recently I was tasked with grouping a large number of DNA oligonucleotides, and exploring the criteria by which to group them was a lot of fun using various R libraries. In the span of a few days I learned how to use k-means clustering, how to employ an UpSet plot, and how to build a phylogenetic tree.
by Blahah on 6/18/24, 3:40 PM
Absolutely beautiful - both the clear explanation and the idiomatic (tidyverse style) R packages and code walkthrough. The combination of the two allowed me to read through and understand in one go. And I have immediate uses for the packages. Thanks!
by evilturnip on 6/18/24, 5:13 PM
In planetary rendering circles, the cubified sphere is a great method and I'm glad he went over that here.
I should say you do get distortion where the cube faces meet at the edges. May or may not be a problem depending on how your texturing.
by washedup on 6/18/24, 5:52 PM
Amazing work. Simple, easy-to-use code. This must have been quite the effort. It's honestly stunning work. Also, good to see R is still alive and well!
by pixelpoet on 6/18/24, 7:58 PM
I would just directly ray trace it, no subdivision. Then it becomes something like 100 lines of code total, and is probably still faster than the subdiv approach.
BTW I like to call that singularity at the pole god, because I often notice it in env maps as an arsehole in the sky :P
by condwanaland on 6/19/24, 8:49 AM
Tyler, your work in R is always incredible! I love reading about what you've been creating - a lot goes over my head but it's always a blast to read
by zippyman55 on 6/18/24, 2:40 PM
Nice! Love R!
by phkahler on 6/18/24, 8:39 PM
Opensubdiv should be able to do this too. I wonder how much work it would be to glue that on. Maybe there's no benefit at this point? ;-)
by kaeptnkrunch on 6/18/24, 3:25 PM
Nice