7 replies to this topic

[Bjorn]

Hi,

I just discovered this great shaded relief map with oblique view and snow cover:


http://www.finse1222...-i-spotmap.html

What tools and data would I need to create such a map?

Bjørn

[Hans van der Maarel]

In terms of data, you'll need a digital elevation model (DEM), or contour lines from which a DEM can be generated.

As far as software goes, a 3D rendering package is necessary to do something like this. There's plenty of those, with each their own pros and cons (and price range). A partial list:

• Visual Nature Studio
• Vue
• Natural Scene Designer
• Maya
• 3D Studio Max
• ArcGIS with the 3D Analyst extension

[dsl]

Tom Patterson's excellent site has a couple of articles/tutorials about these types of maps.

http://www.shadedrelief.com/
http://www.shadedrel...etric/plan.html
http://www.shadedrel...lan_oblique.pdf

Cheers,
David

Edit:

Also you can probably do something like this in Sketchup. Here's a way to get terrain data into sketchup.
http://www.boxshaped...om/Blog/post/27

[Lui]

Hi!
I think that the main problem is how to recreate a valid and believable snow cover. I'm currently working on one of winter-spring natural looking maps and it is not simple to calculate snow accumulation,... Anyway, I would go with VNS or Vue.

[Bjorn]

Many thanks! I'll have a closer look at the tools you're recommending.

Ideally, the map should be rotatable like the NY Times Vancouver map:
http://www.nytimes.c...-venue-map.html
http://www.cartotalk...p...371&hl=snow

Lui, please notify me if you succeed in creating a realistic snow cover.

Bjørn

[Adam Wilbert]

Two other 3D packages that I've been toying with are Planetside's "Terragen 2" and e-on software's "Vue 9". They may be entirely overkill for this type of map, as they're geared mainly towards cinema visual effects production, but their terrain generation, atmospherics, vegetation algorithms, and lighting models are amazingly sophisticated. Both offer unrestricted trials for non-commercial work. As far as snow-cover goes, they both have built in models for accumulation, melt, runoff, and defining micro-climate zones that can affect the scene. Basically, it comes down to how much time you can spend with the software!

[Lui]

I will, Bjorn. I'm working on ArcGIS implementation because I don't like non georeferenced nature of Vue. Is it possible in newer versions of Vue directly import&export georeferenced data? BTW has anyone seen in the wild a realistic ArcGIS snow accumulation algorithm?

[Nicholas_C]

To my knowledge there is no ArGIS model thus far that could accurately render an "average" snow cover for a given location. But i could very well be wrong.

One of the key problems with studying snow is the extreme spatial variability. The main factors to take into account are a. actual snowfall (varies greatly w/ orographic effects, b. elevation, c. wind erosion/deposition, and d. slope aspect, and e. slope angle; and there's a host of other factors as well. It's quite the complex problem, and the relative influence of said factors varies greatly mountain range to mountain range.

There's certainly been a lot of work done on this, but no "quick fix that I'm aware of. Check out past ISSW proceeding and journals of hydrology/glaciology.

Without local knowledge, I've found the best way to approach this is to find an photo taken at the time of interest, then use it to manually digitize snow-covered areas. , using a bit of artistic license as necessary to achieve the desired look. I draw a polygon covering the greater snow-covered area, then cut out wind-stripped ridgelines, steep faces, sun-melted slopes, etc. Probably not the answer you want, but it's worked for me in small areas of interest.