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@pdfa-lab/fontkit / hheaTable / hhea

Interface: hhea ​

Defined in: src/tables/hhea.ts:10

Represents the parsed header data from the OpenType Horizontal Header Table (hhea).

This table contains high-level typographic and layout metrics used for horizontal text positioning, line spacing computations, and structural limits of the font.

Properties ​

advanceWidthMax ​

advanceWidthMax: number

Defined in: src/tables/hhea.ts:37

The maximum advance width value encountered across all glyphs within the hmtx table.

ascent ​

ascent: number

Defined in: src/tables/hhea.ts:20

The distance from the baseline to the highest ascender in the font. Usually matches the highest point of standard capital letters or accent marks.

caretOffset ​

caretOffset: number

Defined in: src/tables/hhea.ts:71

The horizontal offset displacement value for the text layout cursor. Typically set to 0 for non-slanted fonts.

caretSlopeRise ​

caretSlopeRise: number

Defined in: src/tables/hhea.ts:59

The mathematical rise value used to compute the angle/slope of the caret cursor (rise / run). Set to 1 for purely vertical, un-slanted text cursors.

caretSlopeRun ​

caretSlopeRun: number

Defined in: src/tables/hhea.ts:65

The mathematical run value used to compute the angle/slope of the caret cursor (rise / run). Set to 0 for purely vertical, un-slanted text cursors.

descent ​

descent: number

Defined in: src/tables/hhea.ts:26

The distance from the baseline to the lowest descender in the font. Usually a negative value representing the depth of glyph elements dropping below the baseline.

lineGap ​

lineGap: number

Defined in: src/tables/hhea.ts:32

The typographic line gap. Recommended amount of extra space to add between lines of text during layout rendering.

metricDataFormat ​

metricDataFormat: number

Defined in: src/tables/hhea.ts:77

The format specification structure for the horizontal metric data. Set to 0 for current standard OpenType layouts.

minLeftSideBearing ​

minLeftSideBearing: number

Defined in: src/tables/hhea.ts:42

The minimum Left Side Bearing value encountered across all glyphs within the hmtx table.

minRightSideBearing ​

minRightSideBearing: number

Defined in: src/tables/hhea.ts:47

The minimum Right Side Bearing value encountered across all glyphs within the hmtx table.

numberOfMetrics ​

numberOfMetrics: number

Defined in: src/tables/hhea.ts:82

The total number of valid advance width records present inside the matching hmtx table.

version ​

version: number

Defined in: src/tables/hhea.ts:14

The table version number. Typically 0x00010000 for version 1.0.

xMaxExtent ​

xMaxExtent: number

Defined in: src/tables/hhea.ts:53

The maximum extent value along the horizontal layout axis, calculated as: Max(lsb + (xMax - xMin)).