如何在NSTextView中找到字符的像素位置？

I'm currently using the following code to fetch the logical NSView position of glyphs which is working fine however it seems a bit slow and the positions aren't precisely on the character kerning point and baseline. It very well may be the case that all I need to do is iterate the glyphs themselves one by one and build the rect myself.I'm currently using the following code to fetch