Per Fess Horizontal Split Position Checker
Audit per-pale/per-fess split against envelope midline, not actual curved-shield area equality.
Description
Per-fess geometry concerns a horizontal division across the field.
Per-fess geometry concerns a horizontal division across the field.1
Comparing its measured y position with half the height gives a signed midline offset.
When to use Per Fess Horizontal Split Position Checker
Use this tool to calculate or review the supplied observations under the stated rules. Establish the source tradition, viewing frame, coordinate units and independently annotated features.
How to use Per Fess Horizontal Split Position Checker and understand its results
- Establish the source tradition, viewing frame, coordinate units and independently annotated features.
- Enter fieldHeight, observedSplitY, using the field meanings and rules below, then run the tool.
- Read result.signedMidlineOffset, using the output meanings and calculation rules below.
- Correct any reported input issue and run again. Before using a successful result, check the stated units, signs, reference scope and observation coverage.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| fieldHeight | Field height | number | Required |
| observedSplitY | Observed split y | number | Required |
Require positive field height and split y between zero and height, inclusive. Return split y minus half the field height.
signedMidlineOffset=splitY−fieldHeight/2 Use the matching field units and the exact boundary, ordering and reference rules above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Calculated observation or reference | object |
| result.signedMidlineOffset | signed Midline Offset; preserve the subtraction order and sign defined in the mechanics | number |
{
"input": {
"fieldHeight": 100,
"observedSplitY": 50
},
"output": {
"result": {
"signedMidlineOffset": 0
}
}
}Limitations and assumptions
Use one explicit y-axis convention. No tolerance, shield contour or heraldic acceptance rule is added.
Missing required fields, unknown fields, wrong types and violated rules return input issues. Numeric values and outputs must be finite. Extremely large composite outputs are rejected.
Alternative or Complementary methods
For a related step, use Per Pale Partition Midline Position Checker: Per-pale geometry concerns a vertical division across the field. For a complementary comparison, use Fess Center Line Offset Calculator: A fess center can be compared with the field's geometric mid-height.
References
Similar or alternative tools
- Per Pale Partition Midline Position Checker
Per-pale geometry concerns a vertical division across the field.
- Fess Center Line Offset Calculator
A fess center can be compared with the field's geometric mid-height.