Home/ Questions/Q 62957
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-10T18:33:26+00:00

I am using CGContextShowText to display text, but when rotating it using CGAffineTransformation ,

  • 0

I am using CGContextShowText to display text, but when rotating it using CGAffineTransformation, the rotation axis is located at the left, not at the center of the drawn text, the code I am using is this:

CGContextSaveGState(context);  CGContextSelectFont(context, 'Helvetica', 20, kCGEncodingMacRoman); CGContextSetCharacterSpacing (context, 1); CGContextSetRGBFillColor (context, 0, 0, 0, 1); CGAffineTransform xform = CGAffineTransformMake(     sin(DegreesToRadians(angle)), cos(DegreesToRadians(angle)),     cos(DegreesToRadians(angle)), -sin(DegreesToRadians(angle)),     0,  0);  CGContextSetTextDrawingMode (context, kCGTextFill);   CGPoint degreeDisplayPoint = CGPointMake(100,100); CGContextShowTextAtPoint(context, degreeDisplayPoint.x, degreeDisplayPoint.y, [angleStringWithDegree cStringUsingEncoding:NSMacOSRomanStringEncoding], [angleStringWithDegree length]);   CGContextRestoreGState(context);

Any ideas?

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Translate your object so that its centre is at (0, 0), then rotate it, then translate it back to where you want.

    • 0