Mars Topography in the Clear Line Style
September 8, 2020
If your childhood was blessed by journeys alongside Tintin and Captain Haddock, then the Clear Line (Ligne Clair) style of illustration will be somewhere in your visual memory. If not, go check out this introduction: Ligne Claire then come back.
This projects attempts to portray topographic data from the Mars Reconnoissance Orbiter in the Clear Line style, using non-photorealistic rendering processes.
We start at the source: DTM files provided by the brilliant group at University of Arizona Lunar and Planetary Laboratory: HiRISE (High Resolution Imaging Science Experiment). On that page, anyone can access gigas and gigas of digital terrain models (DTMs) as well as the original images that the height maps are derived from.
A favorite spot for martian tourism is Candor Chasma, a canyon within the Valles Marineris system of canyons. It is known for its distincitive terrains that suggest erosion by flowing water.
The basic raw data is shown on the left panel below.
The heights are mapped to grayscale values in the image and can be rendered in many ways to communicate the shape as we are accustomed to.
After some importing related scripting and data reductions (the raw data is too much for my machines to handle) we can design some custom shaders and rendering settings to give the heightmaps a style not too far off from that of the Tintin graphic novels.
Just to make it very clear, this is real topographic data from the Martian surface, rendered in a cartoony way. Here are two renders, of the same area, one using the Clear Line Style, and the other done with OpenSpace, showing a more photorealistic version of Candor Chasma. Both use the same HiRISE data sets.
And since our camera is movable, we can adjust positions and field of views easily. Here is a more panoramic view showing the entrance to Tithonium Chasma off in the distance.
Candor Chasma isn’t the only fun place on Mars. In just a few weeks from now (Feb 18, 2021), the Perseverance rover will land in Jezero crater and begin its search for rocks and other specimens that might help us understand more about the history of Mars. If Tintin and Snowy managed to stow aboard, they might see something like this when they arrive.
And, one more just for the fun of it:
Notes: All images on the page are CC BY-NC, Please credit James Hedberg if you reuse for non-commercial use. For any other inquires please contact.