# `GSLayer lsbAtHeight:`

*Instance Method*

Left side bearing measured at a y coordinate.

## Declaration

```swift
func lsb(atHeight height: Int) -> CGFloat
```

```objc
- (CGFloat) lsbAtHeight:(NSInteger) height;
```

```python
lsbAtHeight_(height: int) -> float
```

## Discussion

Returns `NSNotFound` when no outline intersection can be measured at the height.

## See Also

### Horizontal Metrics

- [`GSLayer.width`](/Core/GlyphsCore/GSLayer/width) — Advance width for horizontal text layout.
- [`GSLayer.LSB`](/Core/GlyphsCore/GSLayer/LSB) — Horizontal distance from the origin to the left outline edge.
- [`GSLayer.LSBFast`](/Core/GlyphsCore/GSLayer/LSBFast) — Cached left side bearing without updating metrics.
- [`GSLayer LSBPlain`](/Core/GlyphsCore/GSLayer/LSBPlain) — Left side bearing without normalizing the no-outline value.
- [`GSLayer.RSB`](/Core/GlyphsCore/GSLayer/RSB) — Horizontal distance from the right outline edge to the advance width.
- [`GSLayer.RSBFast`](/Core/GlyphsCore/GSLayer/RSBFast) — Cached right side bearing without updating metrics.
- [`GSLayer RSBPlain`](/Core/GlyphsCore/GSLayer/RSBPlain) — Right side bearing without normalizing the no-outline value.
- [`GSLayer setLsb:atHeight:`](/Core/GlyphsCore/GSLayer/setLsb:atHeight:) — Sets the left side bearing measured at a y coordinate.
- [`GSLayer rsbAtHeight:`](/Core/GlyphsCore/GSLayer/rsbAtHeight:) — Right side bearing measured at a y coordinate.
- [`GSLayer setRsb:atHeight:`](/Core/GlyphsCore/GSLayer/setRsb:atHeight:) — Sets the right side bearing measured at a y coordinate.