Map-Viewer
Many users of the 'CPT Designer' program utilize it to create CPT files that will then be employed to color a hypsometric map. When you are designing or editing a CPT file for that purpose, it is very handy to be able to instantly test your CPT file, and see what it looks like when used with real topographic data, from a Digital Elevation Model. That is exactly what the Map-Viewer does. The CPT File does not need to be saved beforehand. Once you have a CPT loaded into the 'CPT File Window', just go to the 'Map-Viewer', which is located in the tabbed-pages to the upper-right of the program window. Click it's 'Go' button, leaving the other settings at default, and the map-creation routine starts. Its progress is shown on the Status Bar. When finished, a world map will be shown in the 'Map-Viewer' panel.
Click 'Save' if you wish to export the map as an image. This can be very useful for archival purposes, if you save it in the same directory as your CPT file. You can choose from Jpg, Gif, Png, Bitmap, or Tif image-types when saving a map.
The program has five levels of elevation data included, but can cope with up to 11 levels. The levels are selected with the control adjacent to 'ArcMin', where level 60 is the coarsest, derived from a 60 arc minute global relief dataset, and level 01 is the finest, derived from a 1 arc minute global relief dataset. The following table shows the parameters for each 'Scale' setting:
ETOPO1 Global Elevation Dataset
ArcMin Natural Size Resolution Included
60m 361 x 181 px 111 km Yes
30m 721 x 361 px 55 km Yes
20m 1081 x 541 px 37 km Yes
15m 1441 x 721 px 28 km Yes
10m 2161 x 1081 px 18 km Yes
06m 3601 x 1801 px 10 km No
05m 4321 x 2161 px 9 km No
04m 5401 x 2701 px 7.5 km No
03m 7201 x 3601 px 5.6 km No
02m 10801 x 5401 px 3.7 km No
01m 21601 x 10801 px 1.8 km No
Datasets for levels 60-10 are included with the program. Levels 06-01 are available as a separate 479 MB download. When they are requested, the program will open a file window so you can navigate to them.
The data was processed from datasets provided by the GMT program (LGPL License) at http://gmt.soest.hawaii.edu/doc/latest/datasets.html (Link will open in your Browser) which in turn was processed from ETOPO data (Link will open in your Browser).
NB: the world datasets have values in metres, not feet. If your data has values greater than 8848, then you will need to convert it from feet to metres, using the options on the 'Values 1' tool-page.
The 'Resize' control sets the magnification factor of the map, over the range: 0.1 to 3.0. A magnification factor of '1.0' leaves the map-size unchanged, and will produce the sharpest image.
After clicking the 'Go' button, a new window will open that lets you set the bounds of the map. A world map is shown, with a dashed rectangle that shows the currently chosen bounds. Left-click within the rectangle and then drag it to another location to re-position it. Click and drag the green handle in the bottom-right corner to resize it. You can also adjust the bounds by altering the values in the NSEW controls.
When using the Datasets '02m' and '01m', a maximum size of 180 degrees wide by 90 degrees high is allowed. This is to stop the program using more than the 2GB allowed in 32bit applications.
Click 'OK' to process your settings.
For quick archival purposes, a Scale of '2' and a 'Multiplier' of '1' is recommended. For larger maps, a Scale of '5' and a 'Multiplier' to suit the desired size is recommended, though of course the larger the Scale, the longer the map will take to make.