Simulate curvature of the earth

hi there,

maybe it´s possible to add some curvature to a terrain, so that very large extents can be curved a bit, just like real earth?
A parameter like “add curvature scale dependent or scale - independent” would be awesome.

And of course some artistic setting for a “little-big-planet” kind of terrain for creating a round planet would be also nice!

Kind regards

The curvature would mean the terrain is bent as per the earth’s surface, which in turn would mean that features would be distorted accordingly. But since bent features would mean defying the gravity vector or simply “normals”, it would not be possible using the present architecture of wm, since it works on heightfield data.

How about you curve a plane in 3ds max or maya and start building on that?

But you have to build the world flat, export heightmap and masks, bend the plane in max or maya, apply displacement on it (taking computed normals into account. But that would still mean stephen cannot add that feature to world machine. (Yet?)

I dont think that the WM scripts are ment to do those kinda calculations

I think about it this way:

Since it works with heightfield data and can produce a height/displacement map - where every pixel gets a value - why not add
a calculation to modify the values of a map? Like in first pass, calculation as always. Then (if “add curvature” is selected) go on and do this steps:

  1. Get size of extent
  2. Calculate, how much distorted this extent would get, when projecting it to an “earth-like” sphere (1,96 m for 5000 m, taking this formular y = L² / (2 * 6371000)
  3. Change the “height-value” for every pixel/point by interpolation for every point on extent (assuming center of extent is “Zero” distortion)
  4. You get an extent/heightfield with curvature

Cheers!

That won’t look right, since the features still point on up axis, rather than the normals on your curved plane.

Yes you would only get curved distortion
Sinds you cannot bend axis…iff im correct

Best way is to bend in a secundairy program

Ok I see - was just a quick thought 8)

It would be a mayor calculation
Not only z axis like what you explained
But also x and y have to be recalculated very strict

Else you wil ripp you world/terrain apart
Like any displacement