Description
For a valid Unicode scalar return plane=floor(point/65536), planeOffset=point%65536, and supplementary when point is at least 65536.
Text positions can be measured in UTF-16 code units, Unicode code points, grapheme clusters, or modeled display columns. These coordinates are not interchangeable. Invisible markers and delimiter policies can also affect interpretation even when a string looks unchanged, so the chosen representation needs to stay explicit.
For a valid Unicode scalar return plane=floor(point/65536), planeOffset=point%65536, and supplementary when point is at least 65536.
When to use this tool
Use Unicode Scalar Supplementary Plane Index when you need the stated marker, coordinate, delimiter, or normalization operation under an explicit text representation.
How to use the tool and how it works
- Enter point. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read plane, planeOffset, supplementary. Inspect supplementary before interpreting the associated values.
For a valid Unicode scalar return plane=floor(point/65536), planeOffset=point%65536, and supplementary when point is at least 65536.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| point | Point | Required. Safe integer. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| plane | Plane | Required. Safe integer. |
| planeOffset | Scalar’s numeric position within its 65536-value plane. | Required. Safe integer. |
| supplementary | Supplementary | Required. Boolean. |
{
"input": {
"point": 128512
},
"output": {
"plane": 1,
"planeOffset": 62976,
"supplementary": true
}
}Limitations and assumptions
- Surrogates and out-of-range values are rejected. A valid scalar can still be unassigned or a noncharacter; this is numeric plane classification, not glyph or character assignment verification.
- The field tables state structural bounds; the mechanics also specify cross-field constraints. Malformed inputs and unsupported domains cause errors. A successful false flag, empty branch value, or zero placeholder has the meaning stated above and is distinct from an input error.
Alternative or Complementary methods
Choose the coordinate system required by the consumer. Use a full parser, renderer, or segmentation method when a local marker or delimiter rule cannot determine the complete text behavior.
References
Similar or alternative tools
- Text: Unicode Private Use Plane Label
Classify the three Unicode private-use areas without assigning character semantics or confusing supplementary-plane terminal noncharacters with private use.
- Unicode Scalar Bidi Isolate Marker
Recognize U+2066–2068 as directional isolates and U+2069 as terminator.