Measure Menu
This article and much of our Knowledge Base now lives at the CalTopo training site. This specific page can be found here. Please go there for the most up to date information, as well as more comprehensive instructions for using CalTopo.
The Measure menu provides tools for displaying information about points, lines and polygons drawn on the fly.
This menu has three sections:
Point
For tools in this section, click on the tool name and then click the map for the desired point.
Some of these tools are also available for previously drawn markers via the Marker Tool Menus.
Position & Elevation
Display elevation and coordinates for this point in various coordinate systems. You can toggle between the "Read As" and "Coordinates - NAD27 CONUS" to see the coordinates in either the WGS84 or NAD27 datum.
Sun Exposure
Graph of sun exposure for this point by day of the year and time. Move the cursor over the graph to change the date and time. In this example the cursor cross-hair is at April 10th at 1:00 PM GMT.
NOAA Forecast
Display current conditions and forecast for this point. The following image is just a portion of the information that will be displayed.
Simulated View / View From Here
Display a simulated view from this point. This tool opens in a new tab with lots of options for changing the view. The default view is to the north with a wide angle and middle level of view. Using the cursor, you can pan side-to-side to rotate around the point, and up-and-down to raise or lower the view.
The locator in the lower right corner shows the level and direction of the view. You can hide it by clicking "hide locator". The "+" / "-" buttons in the locator zoom the locator view in and out.
On the top bar, you can change the coordinates, the quality of the view, whether to show a wireframe, topo, image, combination of image / wireframe or a combination of topo / wireframe, and what level the view is from.
The "+" / "-" buttons in the upper left corner zoom the view angle in and out
In the left bar, there is a list of peaks (where applicable). Clicking on a peak name will direct the view towards that peak.
Here's an example of an imagery view.
If you see a spot on the view that you'd like to pinpoint its location, right-click the spot and then click "Map This Spot" and a map of the location will be displayed.
Line
For tools in this section, click on the tool name and then draw the desired line. See the "Lines and Polygons" article for help Drawing Lines.
Some of these tools are also available for previously drawn shapes via the Line and Polygon Tool Menus.
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Measure Distance: Measure the distance of a line.
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Take Bearing: Measure the distance and bearing between the beginning and end of a line.
Profile
A graph of the elevation changes of a line or the perimeter of a polygon. Moving the mouse along the graph shows data for the point at the cursor.
Clicking "Expand" to view Terrain Statistics display, see below.
Terrain Statistics
Display elevation, slope, aspect, tree and land cover data for a line or a polygon. If the object being measured is a polygon, the terrain statistics shown are for the interior of the polygon.
Click "Resample" to improve Gain / Loss Numbers.
Click the following file types to export the information:
1. png: Generates a PNG image of the profile.
2. pdf: Generates a PDF of all of the terrain statistics.
3. csv: Generates a CSV file of the terrain statistics
Click "collapse" to view the Profile display (see above).
Polygon
For tools in this section, click on the tool name and then draw the desired polygon. See the "Lines and Polygons" article for help Drawing Polygons.
Measure Area
Measure the area of a polygon.
Terrain Statistics
Display elevation, slope, aspect, tree and land cover data for the interior of the polygon. For more information, see Terrain Statistics in the Line section above.
Alternate Access Methods
These tools are also available by right-clicking the map. If the position clicked does not contain an object, this basic menu will appear:
If there is an object, the measure menu will appear below the object specific menu. The example shown here is for a marker:
These same tools are also available for various objects that have been previously drawn through the tool menus for those objects.