# layoutManager(_:shouldGenerateGlyphs:properties:characterIndexes:font:forGlyphRange:) Enables customization of the initial glyph generation process. ``` optional func layoutManager(_ layoutManager: NSLayoutManager, shouldGenerateGlyphs glyphs: UnsafePointer, properties props: UnsafePointer, characterIndexes charIndexes: UnsafePointer, font aFont: NSFont, forGlyphRange glyphRange: NSRange) -> Int ``` ## Parameters `layoutManager` The layout manager doing the layout. `glyphs` A pointer to the layout manager’s glyph cache. `props` A pointer to a buffer containing glyph properties for the glyphs in the cache. `charIndexes` A pointer to the starting index for the characters in the text storage for which glyphs are generated. `aFont` A font to override the font attributes in the text storage for the specified character range. `glyphRange` The range of glyphs in the glyph cache to set. ## Return Value The actual glyph range stored in this method. By returning `0`, it can indicate for the layout manager to do the default processing. ## Discussion This message is sent whenever the layout manager is about to store the initial glyph information via [`setGlyphs(_:properties:characterIndexes:font:forGlyphRange:)`](/documentation/AppKit/NSLayoutManager/setGlyphs(_:properties:characterIndexes:font:forGlyphRange:)). To customize the initial glyph generation process, this method can invoke [`setGlyphs(_:properties:characterIndexes:font:forGlyphRange:)`](/documentation/AppKit/NSLayoutManager/setGlyphs(_:properties:characterIndexes:font:forGlyphRange:)) with modified glyph information. > Note: > Querying glyph information surrounding `glyphRange` could lead to recursion since the data might not be available yet. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)