# CTFontGetOpticalBoundsForGlyphs(_:_:_:_:_:) Calculates the optical bounds for an array of glyphs and returns the overall optical bounds for the run. ``` func CTFontGetOpticalBoundsForGlyphs(_ font: CTFont, _ glyphs: UnsafePointer, _ boundingRects: UnsafeMutablePointer?, _ count: CFIndex, _ options: CFOptionFlags) -> CGRect ``` ## Parameters `font` The font reference. `glyphs` An array of glyphs. `boundingRects` An array of s to receive the computed glyph bounds. This parameter can be `NULL`, in which case the function only calculates the overall bounding rectangle. `count` The capacity of the `glyphs` and `boundingRects` buffers. `options` Reserved, set to zero. ## Return Value This function returns the overall bounding rectangle for an array of glyphs. The `boundingRects` parameter returns the bounding rectangles of the individual glyphs. These rectangles are the design metrics from the font transformed in font space. ## Discussion Fonts may specify the optical edges of glyphs that can be used to make the edges of lines of text line up in a more visually pleasing way. This function returns bounding rectangles that correspond to these specifications if the font provides them; otherwise, it returns typographic bounding rectangles, composed of the font’s ascender and descender and a glyph’s advance width. --- 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)