Ellipsis vs Three Periods Width Compare
Compare measured ellipsis glyph versus three periods including both pair-kerning adjustments and font units; no assumed glyph equivalence or font lookup.
Description
An ellipsis and three periods can have different advances.
An ellipsis and three periods can have different advances. Pair kerning contributes twice to the three-period sequence.1
Enter positive units/em, nonnegative glyph advances and signed kerning producing nonnegative three-period advance. Return both em advances and signed difference.
When to use Ellipsis vs Three Periods Width Compare
Use Ellipsis vs Three Periods Width Compare when you need to evaluate the supplied records under the calculation and evidence rules below. No glyph lookup, shaping or assumed equivalence is supplied.
Prepare measured font or typeset-layout values and the explicit design policy requested. For text or font bytes, use the supported syntax explained below.
How to use Ellipsis vs Three Periods Width Compare and understand its results
- Prepare measured font or typeset-layout values and the explicit design policy requested. For text or font bytes, use the supported syntax explained below.
- Enter ellipsisGlyphAdvanceUnits, periodGlyphAdvanceUnits, measuredPeriodPairKernUnits, unitsPerEm using the field table and calculation rules, then run the tool.
- Read ellipsisAdvanceEm, threePeriodsAdvanceEm, signedEllipsisMinusPeriodsEm. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| ellipsisGlyphAdvanceUnits | Ellipsis glyph advance units | number | Required |
| periodGlyphAdvanceUnits | Period glyph advance units | number | Required |
| measuredPeriodPairKernUnits | Measured period pair kern units | number | Required |
| unitsPerEm | Units per em | number | Required |
Enter positive units/em, nonnegative glyph advances and signed kerning producing nonnegative three-period advance. Return both em advances and signed difference.
threePeriods=3periodAdvance+2pairKern; delta=(ellipsis−threePeriods)/unitsPerEm Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| ellipsisAdvanceEm | Ellipsis advance em | number |
| threePeriodsAdvanceEm | Three periods advance em | number |
| signedEllipsisMinusPeriodsEm | Signed ellipsis minus periods em | number |
{
"input": {
"ellipsisGlyphAdvanceUnits": 800,
"periodGlyphAdvanceUnits": 250,
"measuredPeriodPairKernUnits": -10,
"unitsPerEm": 1000
},
"output": {
"ellipsisAdvanceEm": 0.8,
"threePeriodsAdvanceEm": 0.73,
"signedEllipsisMinusPeriodsEm": 0.07
}
}Limitations and assumptions
No glyph lookup, shaping or assumed equivalence is supplied.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Hanging Punctuation Offset em: Hanging punctuation translates a glyph relative to a margin using its measured bearing and advance. Optical preference remains caller-selected. For a complementary task, use Figure Space Monospace Equal Width Check: Figure-space width can be checked against each measured numeral advance. A monospace name alone does not establish equality.
References
-
Ellipsis vs Three Periods Width Compare — tool.io
Similar or alternative tools
- Hanging Punctuation Offset em
Hanging punctuation translates a glyph relative to a margin using its measured bearing and advance. Optical preference remains caller-selected.
- Figure Space Monospace Equal Width Check
Figure-space width can be checked against each measured numeral advance. A monospace name alone does not establish equality.