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New Raster Map System
Complete List of all Changes
Change Id: 604 Written: 2017.10.02

There are two new links on every Mountain, Town and Feature page called "Raster1" and Raster2. These launch the new raster map system that allows you to customize various layers on the map. It has been worked on for the past month. The control form allows you to quickly customize a huge variety of maps. For example, to quickly see where all the big peaks are within 500 km of Vancouver. The GMap system is still best for investigating specific peak, but this gives you a big picture.

Hundreds of hours of work have gone into this system in the past 2 months. Please have a quick look and read at least the introduction of Raster Form - Help. Some of the uses I have found interesting are:

 - turn off various layers so you can see at a glance where items of interest lie. Eg: All the campgrounds.
 - turn on the "Huts" or Car Camp Layers for 100 km radius
 - list all the peaks within 500km of Vancouver, and see where the big ones and most prominent are located
 - set the town labels to be only the first letter. Saves
 - with 300km radius, set ShowHeight to show only the 100m height class of a mountain. In the rockies, look at where all the "30's" are located, and their relative heights to nearest 100m.

Anybody using this new feature, please send me an email telling me what sort of maps you made that you found useful or interesting.

To get the spacing of the mountains to work, I added a "separation" field to the mountain record which contains the distance to the first peak that is both higher and more prominent thana given peak. This is called the "Greater Parent" as opposed to the familiar "Line Parent". The "Greater Parent" is often more meaningful than the line parent. For example, the greater parent of Mount Robson is Mount Whitney, whereas the line parent is just the less familiar Francs peak.

These separation from the Greater parent is used on the new Raster maps to determine which peaks are plotted on the map. This is better than just using a height or prominence cutoff because it makes sure that every part of the map canvas will show the important peaks in that area.

Comments

#6124 - 2017.10.07 Robin Tivy - Distribution of High prominence peaks
In looking at the distribution of high prominence peaks, Glenn mentioned that you can use either GMap or Raster map. He mentioned that sometimes you run into peak limits with GMap. However, you can avoid hitting the limit if you set Minimum Prominence to 1000m. For example, go to Prince George, and launch the new GMap Form. Set the radius to 500 km, and the basemap to t1 and MinProm to 1000m. Now you see the distribution. But if you set the radius to 1000, then you need to set the MinProm to 1500 to avoid the limits.

But the Raster map gives you a nice clean picture because the number of peaks is automatically controlled by the spacing threshold. In areas where there are a lot of concentrated peaks, only the highest will show.

And now, I just added the ability to turn off the labels on mountains. So you can really see the distribution. See the new "Labels" control field.

#6123 - 2017.10.05 Glenn Woodsworth - This should be very useful
I have played around with this a bit. For me, it extends the analytical usefulness of the site. At the moment I am interested in the regional distribution of high-prominence peaks, and this makes it easy to see. GMap Form has the same capability, but if I set the radius to, say, 300 km, it bogs down because of the peak limits.

With this raster map, if you set the radius to 1000, the min prominence to 1000 metres, and spacing to "more", then you see an interesting map that shows a broad, NE-trending band with a paucity of high and prominent peaks running from about Bella Coola to Grande Prairie. This is nothing that can't be seen with a GIS program such as ArcGIS, but most of us don't have ArcGIS.

Good work, Robin.