Creating a Heightfield that wraps around the entire planet

Started by elsyid, March 12, 2012, 04:56:08 PM

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elsyid

Hi all,

So I'm trying to make a procedural planet. I'm able to generate the landscape, but it's created in the form of a square that doesn't wrap around the curves of the planet. Is there any trick to making it wrap around the sphere as opposed to just being a flat plain?


elipsis1

Try using the "Power Fractal" in the "add terrain" section.  This should make what you are looking for I believe.

FrankB

check this out: http://en.tgblog.de/?p=40#more-40

this should help you achieve what you are looking for.

Frank

elsyid

Quote from: FrankB on March 12, 2012, 06:10:29 PM
check this out: http://en.tgblog.de/?p=40#more-40

this should help you achieve what you are looking for.

Frank

Thanks! That is exactly what i was looking for!

jo

Hi,

If you're getting a square block of terrain you're not really creating a procedural planet. The square block more than likely represents a heightfield, which is not procedural.

If you want to create a procedural planet you should be looking at using something like the Power fractal or Alpine fractal as a jumping off point. As ellipsis1 says, you can create these using the "Add Terrain" button in the Terrain project view. These are true procedural methods that cover the entire planet. You can then start modifying the basic planet using other nodes to create different shapes and types of landscape. That's a big topic though!

Regards,

Jo

WAS

#5
Bumping old topic for relevancy in searches and not to create a ruckus of "use search".

Anyways; how would you go about applying a MOLA which is seamless? This deals with blending a section of height map, for, lets say a series. But what about a 2GB+ MOLA which is meant to be seamless on a sphere?

Must you really tile it and figure out all the positions?

Oshyan

It's best to actually create a new topic unless your question/reply is specifically to do with the original poster's questions/text. I'll answer here for now, but may split this off if it creates a less related discussion.

"MOLA" is a specific format - Mars Orbiter Laser Altimeter - that is not otherwise used or creatable by the average person, as far as I'm aware. The MOLA data set is already contiguous (no stitching needed, at least with the MOLA loader in TG). There are various tools in the Geog data loaders in TG to create seamless results, depending on whether your source data is truly seamless. So what is the source of your data?

- Oshyan

WAS

HiRise. It's a mars MOLA. Seamless. "A a seamless GDAL dataset for a spherical projection" or w/e it says in file description when opening in OpenEV or similar.

My question is the same as the original poster. Creating a seamless wrap on a planet.

However I now have a problem where all data is lost in .tiff format. Niether MOLA shader or Heightmap shader can load georeference data. Wish TG had .cub support like most GDAL sets from source.

Oshyan

HiRise is Mars data, but not *MOLA* data. MOLA is a specific instrument. Just so that's clear, in case you get any other confusion from mixing those terms. When dealing with GIS data it's good to be as specific as possible because there are so many data and file types and variations.

Creating a seamless wrap on a planet *with a single file*, especially a non-georeferenced one (i.e. manually-created rather than real-world sampled), is quite different than dealing with a real-world tiled data set with georeferencing. But I do understand why you might have thought it was a more related question.

In any case, my first question would be whether you have tried loading the data directly in TG. If so, what problems are you seeing? Keep in mind that HiRise data is *not* planet-wide and contiguous for Mars. It's quite patchy actually.

- Oshyan

WAS

#9
The file specifically says it was "HiRise" from what I downloaded, however the file is "Mars_MGS_MOLA_DEM_mosaic_global_463m.cub" (download) which was then opened in OpenEV and exported as GeoTiff with original information passed to the GeoTiff (or at least option checked).

The outcome, in a MOLA shader, and Heightmap is blank, or flat with no indication of the terrain being loaded after a extremely long loading time and loading percentage prompt window. Is there another format OpenEV supports that I can convert to since cub is not listed as supported by TG?

For years now I've been tryign to decipher what editors and users have said. And have been trying to get a full seamless planet textured with Mars height information. To play with terraforming it.

Oshyan

Try turning off (unchecking) Georeference and see if your terrain shows up then (after loading in TG).

- Oshyan