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.<p>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.<p>One result of this is the Rectified Lunar Atlas -- one of the guiding maps of the Apollo missions:
<a href="https://sic.lpl.arizona.edu/collection/rectified-lunar-atlas" rel="nofollow">https://sic.lpl.arizona.edu/collection/rectified-lunar-atlas</a>
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: <a href="https://www.rayshader.com" rel="nofollow">https://www.rayshader.com</a>
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.<p>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.
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!
In planetary rendering circles, the cubified sphere is a great method and I'm glad he went over that here.<p>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.
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!
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.<p>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
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