Landscape Projection with Blender?

polyp2000 asks: "I am working on a project that requires me to generate 3D terrain maps from bitmapped contour files. I need to then be able to apply a texture over the top of the terrain. I've been looking for a utility that will enable me to convert from bitmap to 3D landscape projection that can be imported into Blender (either VRML or DXF). After googling around I haven't really come up with anything useful. Might seasoned Slashdot readers know of a solution?"

Comments

Height Modeling

[glk572]

http://www.linuxgraphic.org/section3d/blender/page s/didacticiels/paysages/index-ang.html

Is, I think, exactly what you're looking for, just replace his step of generating the map, with your own to create the image that you need, and out pops your image ready to be textured.

Re:blender won't work

[Vizionary]

BTW, the 64k limit was resolved back in v2.32

Here's an excerpt from the release notes for Blender 2.32...

"- Blender Meshes now have a limit of 2 Billion faces (instead of 64k). This doesn't break backward or upward compatibility, but will cause .blend files to grow about 30% in size. "

Also, in case you're interested, they've recently released Blender 2.33a which can be downloaded here.

There are TONS of new features...

Enjoy!

I think I have some expertise here...

[XenonOfArcticus]

Considering this is what I do for a living.

I won't be able to give you much advice for doing this on Linux, or with Open Source software, since I'm actually not aware of anything that meets both those criteria. I know you didn't stipulate those criteria, but this is Slashdot.

The first issue you face is converting bitmapped contour data into a heightfield. This is not the same as converting greyscale to heightfields, which is a trivial matter. Most of the links proposed already cover using a greyscale image.

A helpful site for you will be http://terrainmap.com/. He has an application (Windows, $free) called Blackart that tries to extract meaning from scanned topo map contours and build a DEM/heightfield out of it. A commercial app (Windows, $1500) that does the same thing is R2V. I've not used either so I can't comment on what you get for your $1500.

Once you have a DEM, you can probably find a way to convert it into a file format that Blender can use as a 3D object and apply texturing to.

The next step is, what kind of texturing? If you just want to be able to slap some pretty-looking colors or natural-looking dirt/rock/grass/snow effects onto it, you can probably do that in Blender. If Blender can't do everything you want, you might try Terragen (Windows/Mac, $free), which is a little more landscape-oriented. I would not recommend VistaPro at this point, it's pretty outdated. TG is at least still being developed, although it's going commercial.

If you need to be able to place real-world image information onto the terrain (airphoto or satellite images, GIS databases, other scanned maps, etc) then Blender is really becoming a poor choice for your needs. (What were your criteria for choosing Blender anyway? It's not known for its landscape capabilities.) The trouble becomes that data like these are usually stored in a different Coordinate System (read the whole VTP site while you're there, Ben's got GREAT info). This means that lining up the position, size and rotation of the two pieces of data is difficult if your software doesn't know how to do it for you. Even most low-end landscape software (Terragen, VistaPro, more free here) can't do this. This is the realm of typically fairly expensive commercial 3D landscape software with a GIS tie-in, such as ESRI's 3D Analyst (Windows, $3500) read info on commercial page above) and my company's Visual Nature Studio (Windows/Mac, $2500).

I won't pretend that my company's product meets your needs, but I have to mention it. I suspect that you'll be able to meet your requirements using some of the tools I outlined first. If however, you find yourself doing this sort of stuff a lot, that's where the polish, integration, support and other frills of commercial software like mine may start to become valuable to you.

Hope you find what you're looking for. If you (or anybody else) have more questions about this, I'd be happy to answer them privately or publicly. As you can see from the above, despite selling my software, I try to be objective and don't always tell you my product is what you need. ;)