How to set leading in CoreText?

[OMH]

You can get it with CTFontGetLeading(aCTFont), but how do you SET it?

Can anyone please explain?

Is there another way around this? Do you have to set the space between the lines manually, perhaps?

[Elaz]

Originally Posted by OMH

You can get it with CTFontGetLeading(aCTFont), but how do you SET it?

Can anyone please explain?

Is there another way around this? Do you have to set the space between the lines manually, perhaps?

You want want to set the maximum height line of the lines and pass it in the paragraph style attribute of the NSAttributedString you use with CoreText:

CTTextAlignment paragraphAlignment = kCTLeftTextAlignment;
		
		CGFloat maxLineHeight = 13.0;
		
		CTParagraphStyleSetting setting[2] = {
			{kCTParagraphStyleSpecifierAlignment, sizeof(CTTextAlignment), &paragraphAlignment},
			{kCTParagraphStyleSpecifierMaximumLineHeight, sizeof(CGFloat), &maxLineHeight}
		};

				
		CTParagraphStyleRef paragraphStyle = CTParagraphStyleCreate(setting, 2);
		
		NSAttributedString* attrString = [[[NSAttributedString alloc] initWithString:contents attributes:
										   [NSDictionary dictionaryWithObjectsAndKeys:(id)myriadProRegular, (NSString*)kCTFontAttributeName,
											paragraphStyle, (NSString*)kCTParagraphStyleAttributeName, nil]] autorelease];
		
		
		CFRelease(paragraphStyle);

And than continue with the CTFrameSetter.
Not included here is the font creation, frame setter creation etc, but if you know your way around coretext, that should help you.

[OMH]

I needed to adjust _minimum_ line height, but then it worked nicely.

"kCTParagraphStyleSpecifierMinimumLineHeight". I found it in CTParagraphStyle.h, if anyone else are interested in these.

Thank you very much, Elaz!