Intervisibility Line-of-Sight Obstruction Angle Checker
Planar line-of-sight height clearance, tangency counts obstructed; no Earth curvature, atmospheric refraction or radio Fresnel analysis.
Description
Intervisibility Line-of-Sight Obstruction Angle Checker: return signed clearance m, obstructing indices.
A straight line of sight has an interpolated height at each intermediate distance. An obstacle at or above that height blocks or touches the line.
This tool returns signed clearance m, obstructing indices. Use the stated units and model convention when interpreting these fields.
When to use this tool
Use this tool when the supplied inputs match the specific operation described above and you need a repeatable result under its stated convention.
- Check the supported input and output contract against an existing calculation or observation.
- Use the complete example to confirm units, selector spelling and result interpretation.
How to use the tool and how it works
- Enter every field in the input table using the stated units and the exact supported selector spelling where applicable.
- Run the tool. Correct input errors before interpreting an output.
- Read the result fields below; use accompanying flags and the stated sign, boundary or model convention when interpreting a number.
Require obstacles strictly between observer and target. Interpolate the endpoint line, subtract every obstacle height and flag zero-based indices with clearance at most zero.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| observerHeightM | Observer height m. Meters. | Finite number |
| targetHeightM | Target height m. Meters. | Finite number |
| targetDistanceM | Target distance m. Meters. | Finite number; greater than zero |
| obstacleDistancesM | Obstacle distances m. Meters. | List of finite numbers |
| obstacleHeightsM | Obstacle heights m. Meters. | List of finite numbers |
| Output field | Interpretation |
|---|---|
| result | Object containing the following named result fields. |
| result.signedClearanceM | Signed clearance m list, in the ordering described in the calculation. |
| result.obstructingIndices | Obstructing indices list, in the ordering described in the calculation. |
{
"input": {
"observerHeightM": 10,
"targetHeightM": 20,
"targetDistanceM": 100,
"obstacleDistancesM": [
50
],
"obstacleHeightsM": [
16
]
},
"output": {
"result": {
"signedClearanceM": [
-1
],
"obstructingIndices": [
0
]
}
}
}Limitations and assumptions
- All heights need one datum. The calculation omits Earth curvature, atmospheric refraction and unlisted obstacles.
- Every declared field is required and unexpected fields are rejected. Numeric inputs must be finite; input errors are distinct from a valid false result or an explicitly qualified output.
- Extremely large inputs and nonfinite or excessively large outputs are rejected. List positions reported by the tool use zero-based indices unless stated otherwise.
Alternative or Complementary methods
Check the underlying observations, units and conventions independently before using the result in a larger workflow. The tools listed below address nearby tasks; compare their inputs and scope before substituting one for this operation.
References
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