Problem
After scaling and rotating a UITextView using gestures, the text is sometimes fuzzy because the transformations are applied to the rasterized bitmap.
Proposed Solution
Once the gesture is complete, I need to return the transform to the identity transform, resize the frame based on the scale, resize the font based on the scale, and then re-apply the rotation transform.
Implementation Attempts
// Store original center before making changes
CGPoint originalCenter = textView.center;
// Restore transform to identity (frame property is invalid while transform is not identity)
[textView setTransform:CGAffineTransformIdentity];
// Attempt 1 - sizeThatFits /////////////////////////////////////////////////////////////////
// Scale font
[textView setFont:[UIFont fontWithName:textView.font.fontName size:textView.font.pointSize*scale]]; // scale refers to the scale of the pinch gesture that just ended
// Set frame to sizeThatFits
CGSize size = [textView sizeThatFits:maxSize]; // maxSize begins with the view frame size and is scaled at the end of each pinch gesture
[textView setFrame:CGRectMake(0, 0, size.width, size.height)];
// Restore Center
[textView setCenter:originalCenter];
// Re-apply rotation
[textView setTransform:CGAffineTransformMakeRotation(rotation)]; // refers to the total rotation from all rotation gestures
// Attempt 2 - manually scale /////////////////////////////////////////////////////////////////
// Scale font
[textView setFont:[UIFont fontWithName:textView.font.fontName size:textView.font.pointSize*scale]];
// Scale frame
[textView setFrame:CGRectMake(0, 0, textView.frame.size.width*scale, textView.frame.size.height*scale)];
// Restore Center
[textView setCenter:originalCenter];
// Re-apply rotation
[textView setTransform:CGAffineTransformMakeRotation(rotation)];
Notes
Everything I try almost works. In some cases, especially after multiple gestures (compounding the error), the text doesn't fit exactly right and will cause line breaks where there were none before.
