Rising Sun Disc Offset Calculator
Rising-sun disc actual center/horizon offset and ideal circular area above horizontal horizon in top-left y-down frame. Caller independently specifies design fractions/radius; cap clips only at horizon, not rectangular flag sides or rays and no national proportion inferred.
Description
A rising-sun disc can lie partly above a horizontal horizon.
A rising-sun disc can lie partly above a horizontal horizon.1
Its center and radius determine an ideal circular segment area in a top-left coordinate frame with y increasing downward.
When to use Rising Sun Disc Offset Calculator
Use this tool when you need to reproduce the stated calculation from measured records or independently selected model inputs. Establish the flag dimensions, orientation, specification, palette, or visual annotations needed for this particular calculation.
How to use Rising Sun Disc Offset Calculator and understand its results
- Establish the flag dimensions, orientation, specification, palette, or visual annotations needed for this particular calculation.
- Enter hoist, callerVerifiedHorizonYFraction, callerVerifiedDiscCenterYFraction, discRadius, following the field table and rules below, then run the tool.
- Read result. Use the output meanings below to interpret units, signs, flags, and any nested result fields.
- Correct reported input issues and run again. For a successful result, check the stated evidence coverage and assumptions before using it in your review.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| hoist | Hoist | number | Required |
| callerVerifiedHorizonYFraction | Caller verified horizon y fraction | number | Required |
| callerVerifiedDiscCenterYFraction | Caller verified disc center y fraction | number | Required |
| discRadius | Disc radius | number | Required |
Enter positive hoist and radius and horizon/center fractions from zero to one. Scale the fractions by hoist. Clamp (horizon−center)/radius to [−1,1] and use the circular-segment expression, giving zero or full-disc area beyond the horizon limits. Flag-edge and ray clipping are not included.
t=clamp((horizonY−centerY)/r,−1,1); A=r²(acos(−t)+t√(1−t²)) Symbols follow the input and output meanings and the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Calculated observation or reference | object |
| result.horizonY | Horizon Y | number |
| result.discCenterY | Disc Center Y | number |
| result.signedCenterToHorizonOffset | Signed Center To Horizon Offset | number |
| result.visibleDiscArea | Visible Disc Area | number |
{
"input": {
"hoist": 100,
"callerVerifiedHorizonYFraction": 0.8,
"callerVerifiedDiscCenterYFraction": 0.7,
"discRadius": 20
},
"output": {
"result": {
"horizonY": 80,
"discCenterY": 70,
"signedCenterToHorizonOffset": -10,
"visibleDiscArea": 1010.9631217141659
}
}
}Limitations and assumptions
The calculation uses supplied geometry, observations, or annotations. It does not establish an official construction specification, national identity, or universal design quality.
Missing required fields, unknown fields, wrong types, and violated calculation rules are input issues. Numeric values must be finite; nonfinite results are rejected. Extremely large composite outputs are rejected.
Alternative or Complementary methods
For a related review, use Sun Ray Count Angular Spacing Calculator: Evenly spaced sun rays divide a full turn into distinct center directions. A chosen start angle sets their rotation without adding a duplicate direction at the end of the circle. For a complementary step, use Crescent Overlap Geometry Calculator: An ideal crescent can be modeled as an outer disc with the overlapping part of a second disc removed. Containment and disjoint cases need explicit treatment before using the partial-overlap formula.
References
-
Rising Sun Disc Offset Calculator — tool.io
Similar or alternative tools
- Sun Ray Count Angular Spacing Calculator
Evenly spaced sun rays divide a full turn into distinct center directions. A chosen start angle sets their rotation without adding a duplicate direction at the end of the circle.
- Crescent Overlap Geometry Calculator
An ideal crescent can be modeled as an outer disc with the overlapping part of a second disc removed. Containment and disjoint cases need explicit treatment before using the partial-overlap formula.