Hi
I am drawing TextKit2 managed NSAttributedStrings into a NSBitmapImageRep successfully, enumerating the Text Layout Fragments is giving me bogus background drawing
This is the core drawing code, its pretty simple: I manage the flipped property myself since NSTextLayoutManager assumes a flipped coordinate.
if let context = NSGraphicsContext(bitmapImageRep: self.textImageRep!)
{
NSGraphicsContext.current = context
let rect = NSRect(origin: .zero, size: self.outputSize)
NSColor.clear.set()
rect.fill()
// Flip the context
context.cgContext.saveGState()
context.cgContext.translateBy(x: 0, y: self.outputSize.height)
context.cgContext.scaleBy(x: 1.0, y: -1.0)
let textOrigin = CGPoint(x: 0.0, y: 0.0 )
let titleRect = CGRect(origin: textOrigin, size: self.themeTextContainer.size)
NSColor.orange.withAlphaComponent(1).set()
titleRect.fill()
self.layoutManager.enumerateTextLayoutFragments(from: nil, using: { textLayoutFragment in
// Get the fragment's rendering bounds
let fragmentBounds = textLayoutFragment.layoutFragmentFrame
print("fragmentBounds: \(fragmentBounds)")
// Render the fragment into the context
textLayoutFragment.draw(at: fragmentBounds.origin, in: context.cgContext)
return true
})
context.cgContext.restoreGState()
}
NSGraphicsContext.restoreGraphicsState()
I have a mutable string which has various paragraph styles which I add to the layout manager / text storage like so
let titleParagraphStyle = NSMutableParagraphStyle()
titleParagraphStyle.alignment = .center
titleParagraphStyle.lineBreakMode = .byWordWrapping
titleParagraphStyle.lineBreakStrategy = .standard
var range = NSMakeRange(0, self.attributedProgrammingBlockTitle.length)
self.attributedProgrammingBlockTitle.addAttribute(.foregroundColor, value: NSColor(red: 243.0/255.0, green: 97.0/255.0, blue: 97.0/255.0, alpha: 1.0), range:range)
self.attributedProgrammingBlockTitle.addAttribute(.backgroundColor, value: NSColor.cyan, range:range)
self.attributedProgrammingBlockTitle.addAttribute(.font, value: NSFont.systemFont(ofSize: 64), range:range)
self.attributedProgrammingBlockTitle.addAttribute(.paragraphStyle, value:titleParagraphStyle, range:range)
range = NSMakeRange(0, self.attributedThemeTitle.length)
self.attributedThemeTitle.addAttribute(.foregroundColor, value: NSColor.white, range:range )
self.attributedThemeTitle.addAttribute(.backgroundColor, value: NSColor.purple, range:range)
self.attributedThemeTitle.addAttribute(.font, value: NSFont.systemFont(ofSize: 48), range:range)
self.attributedThemeTitle.addAttribute(.paragraphStyle, value:NSParagraphStyle.default, range:range)
range = NSMakeRange(0, self.attributedText.length)
self.attributedText.addAttribute(.foregroundColor, value: NSColor.white, range:range )
self.attributedText.addAttribute(.backgroundColor, value: NSColor.yellow, range:range)
self.attributedText.addAttribute(.font, value: NSFont.systemFont(ofSize: 36), range:range)
self.attributedText.addAttribute(.paragraphStyle, value:NSParagraphStyle.default, range:range)
let allText = NSMutableAttributedString()
allText.append(self.attributedProgrammingBlockTitle)
allText.append(NSAttributedString(string: "\n\r"))
allText.append(self.attributedThemeTitle)
allText.append(NSAttributedString(string: "\n\r"))
allText.append(self.attributedText)
self.textStorage.textStorage?.beginEditing()
self.textStorage.textStorage?.setAttributedString(allText)
self.textStorage.textStorage?.endEditing()
self.layoutManager.ensureLayout(for: self.layoutManager.documentRange)
however, i get incorrect drawing for the background color font attributes. Its origin is zero, and not correctly aligned at all with the text.
How can I get correct rendering of backgrounds from TextKit2?
Here is an image of my output:
