Description
Return available and negative-space area shares.
Artwork measurements distinguish physical dimensions, projected regions and scale conventions. Length, area and volume change with different powers of a scale, while frame overlaps and crop geometry depend on which boundaries were measured. A numerical fit does not identify an artwork or establish its historical interpretation.
Return available and negative-space area shares.
When to use this tool
Use Drawing Exercise Negative Space Share when checking the stated artwork dimension, crop, frame or scale relation.
How to use the tool and how it works
- Enter frameArea, subjectArea, excludedArea. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read availableArea, negativeArea, negativeShare. Use the output convention below.
Return available and negative-space area shares. Require nonnegative excluded area, frameArea > excluded and bounded subjectArea; available = frame-excluded, negative = available-subject, share = negative/available.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| frameArea | Frame Area | Required. Finite number. |
| subjectArea | Subject Area | Required. Finite number; minimum 0. |
| excludedArea | Excluded Area | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| availableArea | Available Area | Required. Finite number. |
| negativeArea | Negative Area | Required. Finite number. |
| negativeShare | Negative Share | Required. Finite number. |
{
"input": {
"frameArea": 100,
"subjectArea": 30,
"excludedArea": 10
},
"output": {
"availableArea": 90,
"negativeArea": 60,
"negativeShare": 0.6666666666666666
}
}Limitations and assumptions
- The areas must already avoid overlap; actual image segmentation and artistic interpretation are not performed.
- 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
Inspect the original object, measured boundaries and appropriate complete geometry or catalog record for physical or historical conclusions.
References
Similar or alternative tools
- Drawing Grid Reference Origin
Return a drawing-grid point from supplied origin and spacings.
- Perspective Exercise Measured Convergence Gap
Return top/bottom perspective-line separations and their difference.