# `GSFont copyGlyphs:sourceFontMasterID:targetFontMasterID:addMissing:`

*Instance Method*

Copies glyph layers associated with one master identifier to another master identifier.

## Declaration

```swift
func copyGlyphs(_ sourceFont: GSFont, sourceFontMasterID: String, targetFontMasterID: String, addMissing: Bool)
```

```objc
- (void) copyGlyphs:(GSFont *) sourceFont sourceFontMasterID:(NSString *) sourceFontMasterID targetFontMasterID:(NSString *) targetFontMasterID addMissing:(BOOL) addMissing;
```

```python
copyGlyphs_sourceFontMasterID_targetFontMasterID_addMissing_(sourceFont: GSFont, sourceFontMasterID: str, targetFontMasterID: str, addMissing: bool)
```

## Parameters

- `addMissing` — Pass `YES` to add glyphs that are missing in the receiving font.

## Discussion

The copied layers are added to matching glyphs by glyph name.

## See Also

### Master Content

- [`GSFont addFontMasterAndContent:`](/Core/GlyphsCore/GSFont/addFontMasterAndContent:) — Adds a local master and copies the content associated with it into the font.
- [`GSFont insertFontMasterAndContent:atIndex:`](/Core/GlyphsCore/GSFont/insertFontMasterAndContent:atIndex:) — Inserts a local master and copies the content associated with it into the font.
- [`GSFont removeFontMasterAndContent:`](/Core/GlyphsCore/GSFont/removeFontMasterAndContent:) — Removes a local master and the layer content associated with it.
- [`GSFont replaceFontMasterAtIndex:withFontMaster:`](/Core/GlyphsCore/GSFont/replaceFontMasterAtIndex:withFontMaster:) — Replaces a local master at an index without changing layer content.
- [`GSFont copyLayersFrom:sourceFontMasterID:targetFontMasterID:`](/Core/GlyphsCore/GSFont/copyLayersFrom:sourceFontMasterID:targetFontMasterID:) — Copies layers associated with one master identifier to another master identifier.
- [`GSFont copyInfoFrom:sourceFontMasterID:targetFontMasterID:`](/Core/GlyphsCore/GSFont/copyInfoFrom:sourceFontMasterID:targetFontMasterID:) — Copies master-specific font information from one master identifier to another master identifier.
- [`GSFont addFontAsNewMaster:`](/Core/GlyphsCore/GSFont/addFontAsNewMaster:) — Adds a master from another font as a new local master.
- [`GSFont addMasterFromInstance:error:`](/Core/GlyphsCore/GSFont/addMasterFromInstance:error:) — Adds the generated contents of an instance as a new local master.