BobBooth
commented
6 years ago Line of Sight 3D Analyst core tool has a "use curvature" parameter http://pro.arcgis.com/en/pro-app/tool-reference/3d-analyst/line-of-sight.htm
use_curvature (Optional) Indicates whether the earth's curvature should be taken into consideration for the line-of-sight analysis. For this option to be enabled, the surface needs to have a defined spatial reference in projected coordinates with defined z-units.
CURVATURE —The earth's curvature will be taken into consideration. NO_CURVATURE —The earth's curvature will not be taken into consideration. This is the default.
lfunkhouser
AEversole
This Enhancement is for the interface of the addin tools for Pro provided in the download on the following page. http://solutions.arcgis.com/defense/help/military-tools/
Steps to Demonstrate: Documentation: The following tools do not indicate or document if or how the tool will adjust for the curvature of earth.
Create linear lines of sight - http://solutions.arcgis.com/defense/help/military-tools/arcgis-pro/creating-linear-line-of-sight.htm- - Creating radial line of sight - http://solutions.arcgis.com/defense/help/military-tools/arcgis-pro/creating-radial-line-of-sight.htm
Both tools request "The input surface data must be in a projected coordinate system." This type of system generally represents a flat surface and does not represent any curvature. The tool should be responsible for applying a curvature to the output.
For note, The approximate distance to the horizon from an observer close to the Earth's surface where d is in kilometres and h is height above ground level in metres. The constant 3.57 has units of km/m½. d approx 3.57*{sqrt {h}} - https://en.wikipedia.org/wiki/Horizon
In Addition to applying a equation to the outputs, this issue could also be avoided by documenting the expectation and/or providing guidance via the documentation.
Steps to Reproduce: 1 Open a map with the appropriate elevation surface. 2 Open the Military tools ribbon (install the Solution if not installed) 3 Click visability 4 Using RLOS for example, Set the tool Parameters:
5 Run the tool. 6 The expected horizon should be Apx 5.04 KM based on the listed equation however the map shows visible area past this expected distance.
Workaround: Apply the workflow from the tool box version of the radial line of sight tool in the Military_Tools_pro toolbox as in testing they do account for Horizon.