Description
Return both radius×sweep lengths and offset×sweep difference.
Angle-based pattern calculations distinguish linear intake, chord, arc and unoriented grain direction. Degrees and radians are not interchangeable, and a local geometric relationship does not model fabric deformation or three-dimensional fit.
Return both radius×sweep lengths and offset×sweep difference.
When to use this tool
Use Collar Roll Line Offset Term when you need a stated pattern-angle or arc relationship.
How to use the tool and how it works
- Enter baseRadius, rollOffset, sweepRadians. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read baseLength, offsetLength, difference. Use the output convention below.
Require positive base radius, positive offset radius and nonnegative sweepRadians. Return both radius×sweep lengths and offset×sweep difference.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| baseRadius | Base Radius | Required. Finite number; strictly above 0. |
| rollOffset | Roll Offset | Required. Finite number. |
| sweepRadians | Sweep Radians | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| baseLength | Base Length | Required. Finite number. |
| offsetLength | Offset Length | Required. Finite number. |
| difference | Difference | Required. Finite number. |
{
"input": {
"baseRadius": 10,
"rollOffset": 1,
"sweepRadians": 2
},
"output": {
"baseLength": 20,
"offsetLength": 22,
"difference": 2
}
}Limitations and assumptions
- Offset can be negative and all lengths share units. The concentric-arc model does not account for three-dimensional collar roll or fabric mechanics.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use the full pattern geometry and a suitable construction sample when rotation, grain behavior or fit matters. Verify angle units, branch choice and the meaning of intake before applying an identity.
References
Similar or alternative tools
- Dart Rotation Seam Length Gap
Return each radius×angle arc and (secondRadius-firstRadius)×angle gap.
- Dart Intake Rotation Angle Term
Return 2×asin(intake/(2×radius)).