---
name: "fcft_kerning"
section: "3"
platform: "linux"
package: "fcft"
version: "3.3.3-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/fcft_kerning"
---

# fcft\_kerning(3)

calculate kerning distance between two wide characters

## NAME

fcft\_kerning - calculate kerning distance between two wide characters

## SYNOPSIS

**#include \<fcft/fcft.h\>**

**bool fcft\_kerning(**

**struct fcft\_font \****font***, uint32\_t** *left***, uint32\_t** *right***,** **long \*restrict** *x***, long \*restrict** *y***);**

## DESCRIPTION

**fcft\_kerning**() calculates the kerning distances *x* (horizontal) and *y* (vertical) between the two wide characters *left* and *right*, in pixels.

Both characters must exist in the primary font.

**fcft\_kerning**() is just a convenience function around **FT\_Get\_Kerning**() and as such, it only supports legacy *kern* tables. In particular, OpenType fonts' *GPOS* tables are **not** supported. fcft is not a text shaping library.

## RETURN VALUE

On success, **fcft\_kerning**() returns true, and *x* and *y* are updated with the kerning distance, in pixels.

On error, false is returned. This may happen for several reasons:

- •

  The primary font does not have any kerning information.

- •

  One, or both, of the two characters have no corresponding glyph in the primary font.

- •

  There is no kerning information for this character combination.

## EXAMPLE

See **fcft\_from\_name**()