Topic: Creating the world

Moving out of the chat where BDA got me back on track...

Here are two pretty high res bump maps of the Earth, one from sea level up (0 to +6400 meters), the other down (-8000 to 0 meters):

https://eoimages.gsfc.nasa.gov/images/i … x10800.png
https://eoimages.gsfc.nasa.gov/images/i … x10800.png

My first instinct is to open these in photoshop, use adjustment layers to slide the 0 point to the middle (say RGB=142, which puts zero at roughly the same proportion as the 6400/8000 meter numbers) and then do a color select to grab the below-sea-level stuff and paste it onto the above. Having done this, it seems to create some sharp edges in a few places where I don't think the topography should be very steep. Like the arctic north of Norway & Russia.

If anybody has a few minutes to review my work, I'd appreciate the sanity check.


https://www.visibleearth.nasa.gov/image … topography
https://www.visibleearth.nasa.gov/image … bathymetry


Chat:
"
drewjmore: But this is progress, thanks BDA.
drewjmore: and make some arbitrary decisions about where one map ends and the other begins.
drewjmore: which means I need to shop them together
drewjmore: Argh, seems to be hard to find both the land and the seafloor in the same map.
drewjmore: This might be a good one. https://www.visibleearth.nasa.gov/image … topography
drewjmore: Their stuff is in some odd formats, too. https://solarsystem.nasa.gov/resources/ … -3d-model/
BigDamnArtist: I remember it being a bit of a pain to find when I was looking a cpl years back. But if you google around for CG nasa earth maps it should pop up. Pretty sure they also have the other planets in there too.
drewjmore: I've been to usual places, GIS data and whatnot, but maybe I didn't check NASA specifically. brb
BigDamnArtist: I cant look it up right now, but if you google around NASA has super high res maps available, and I'm pretty sure there was a bump map in there when I was looking.
drewjmore: #4: profit!
drewjmore: ...
drewjmore: Then I tessellate the crap out of it and export to OBJ which I import into Fusion 360.
drewjmore: I've got a pretty low-res map on a globe in Max which looks okay.
drewjmore: *want to
drewjmore: My router-table robot thingy is working well, and I wan tot try making a hollow wooden globe with it.
drewjmore: Anyone know of a good place to find one?
drewjmore: CG assets question: a really good bump map of a topographical earth.
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Re: Creating the world

Still at work so I cant actually try it, but heres what my workflow would be based on what I think is going on:

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ZangrethorDigital.ca

Re: Creating the world

How do you mask an area to Alpha?
I was using selection tools to achieve this, (color select (pick the 142 color that indicates 0m, invert selection, now all the seafloor is selected, copy-paste) but an alpha blend sounds more flexible.

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Re: Creating the world

Hmm, weird. The preview image I had on mobile was the colour version with the landmasses all as solid black that would have been pretty easy to pull a colour selection on, but it looks like the actual map has them as solid white which is not particularly useful.

You could try this site: http://planetpixelemporium.com/earth8081.html

Grab the specular mask, and just do a colour selection > mask, I have no idea if the map lines up with the Nasa ones, but it's worth a shot just to get a bulk mask of land masses to use as a mask.

ZangrethorDigital.ca

Re: Creating the world

The eyedropper in the color select tool seems to do what  I need in place of explicitly making an alpha mask. Self taught, so I may not grok the terminology, but I think when I copy-paste from the seafloor image onto the land image PS creates a new layer with the masking I need based on the color selection.

So now in Max I've got a nice bump/displacement mapped mesh.
Odd to look at the planet this way. The political divisions are sooooo not there; Russia and Alaska are one thing, Europe is unified. Florida is barely recognizable.

https://photos.smugmug.com/ForWeblinks/i-WRjB6Np/0/e273e6f4/X3/Max-cap01-X3.jpg

Next, importing this into Fusion360. Exporting an OBJ from Max with triangular faces was a bust, Fusion can see the mesh as a mesh but can't convert it to usable solid geometry. So after much trial and error I used a MeshSmooth modifier on the base sphere, before the mesh-map displacement, to convert the faces to quads instead. Now Fusion agrees it would like to convert that mesh into BREP's, but it's been choking on it for like 4 hours now. It's a lot of faces, so either we'll get there eventually, or I need to cut back on my face count a bunch. Looking into mesh optimizations in Max now...

Last edited by drewjmore (2021-05-12 21:35:16)

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Re: Creating the world

Tweaked the Sphere's parameters and only needed to Tesselate on the polygons to export->import a usable mesh into Fusion. Dropped the face count from 500k to 35k which has made Fusion much happier. For reasons that are not clear to me, now I can use T-splines to sculpt the mesh onto my solid geometry which eliminates the B-rep conversion that was taking so much processor time. Fusion seems to make some decisions behind the scenes (without my input) about the imported mesh which affect the usability of the result.

So I've got the mesh intersected with the 'real' physical tiles that I'll be machining, but now I need to figure out how to re-orient them into an unfolded flat piece. It was easy enough with the original 'bodies,' but somehow the intersected 'Components' don't respond the same to the move commands. Tutorial vids here I come.

https://photos.smugmug.com/ForWeblinks/i-jgsK3rS/0/86925a19/X3/Unfolding-01-X3.png

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Re: Creating the world

How it's going:

https://photos.smugmug.com/ForWeblinks/i-pdDkqWc/0/f9bb2154/M/2%20Tris%20w%20toolpaths-M.png

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