Monday, March 30, 2009

Presentation: Hillshading and Draping

Hillshading and draping are tools that take a map to a whole new level. Hillshading makes the map look three dimensional and can be useful when identifying certain objects, such as river valleys and lowland areas, on a map. Draping means literally draping an image, such as a satellite image, over a terrain. Here are some examples of both tools.

This is a nice example of hillshading of the San Francisco Bay Area. If you look at a regular map of the same area, you might wonder why the bigger population centers are located in certain places. But when you see this map, you can tell how the topographic setting of the area affects where towns are located at. If you zoom close enough, you can tell that major roads are located in either valleys or on relatively flat ground.

This example map of Mile Creek Natural Area in Ithaca, New York shows a hillshaded map from an interesting angle. Digital raster graphics are combined with hillshading based on DEM. It is nice to see the effect of the contour lines, how the cartographer didn't get rid of them but chose to keep them in the map.  

Here is a nice black and white map of the Easter Island from the Australian National University. This shows how effective hillshading can be even without the use of color.

This is a geological map draped over a topographic map. Combining geological data with the elevation makes sense since you can distinguish the different geological "categories" (sorry, I have no background in geology) and where they are located in the topographical setting.

A satellite image, such as Landsat image in this map can be draped over a digital elevation model. The nice thing about this map is that the way it is displayed, it looks more three dimensional than draping the same image over a "flat" map. 

My last example is perhaps the most dramatic one of what draping can do. This is another Landsat image draped over a topographic map (from NASA's Shuttle Radar Topography Mission). It displays a part of Southern California. This map is perhaps the most life-like and illustrates the difference between elevations.  

Wednesday, March 25, 2009

Lab 7

Whew!! Operation Barbarossa finished. Was it a success? Not for the Germans but for the one Finn who wanted to map it - YES!! What I really like about my map is:

1) it's DONE!!
2) the pop-ups are pretty neat and (in my opinion) easy to read
3) the colors are nice, although I haven't taken the time to figure out how to post the map without the browser background changing as well
4) the basemap is nice, it took forever to do but I'm very happy with the result!
5) did I mention it's DONE?? Well it is! And I cannot believe it! 

Sure there are some things that are not so perfect but who cares. I'll try to work on the shape tween a bit when I have the time (?!?) and there is a tiny shift in the basemap in the last frame I couldn't quite figure out how to fix. Oh details..

"Drawing" this map gave me some ideas for my final project. I wasn't sure how to do this one thing but figured it out and now I know how to take it a step or two further in the final project. 

Wednesday, March 18, 2009

Wild fire progression in San Diego

This was a pretty neat map I found on the internet. Not the first one on the page, you'll have to scroll down to the other ones. The maps are 3D and I think they've done a great job showing the terrain of the area and how the fires spread. The maps have lots of potential (it would be great if the user could control the timeline, for example). 

Lab5.. Take two

So I know we're supposed to post lab 6 by now but surprise! I'm still in lab 5. Had some major difficulties with the buttons and wasn't paying enough attention so the map shifts a little in the last frame of the movie. But anyway, this is it so far. 

The buttons still don't work like they're supposed to. What's really weird is that you can only choose the date buttons (such as August25) when the movie is stopped in the beginning and not while the movie is playing. 

I've been working on this map on a 20" screen and when I'm trying to load it up on a 17" screen it is just too big. :( 

Something positive about the map? I actually like the basemap. It took a loooong time to "re-draw" all the country boundaries and I wish I had changed it to represent what Europe looked like in 1941. I like my caret and I think the flags are good representations of German troops. 

Off to lab #6..

Wednesday, March 4, 2009

lab5..

Yikes. Something is wrong with my timeline. So I ended up doing only one army unit for now to because I think it moves waaaaaay too slow. I used 10 frames to represent a day. Anyway, here is my "lab" or what I've done so far. No controls or timeline, just a box moving across the screen. I want to change the symbols to tanks (for the tank units) and really get the timeline right. Sorry for the horrible lab, I'll work on it during the break.
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