Ios – How to use CGAffineTransformMakeRotation

cocoa-touchcore-graphicsiosquartz-2d

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I want to draw text use Quartz 2D. The "menu" direction is wrong. I want "Menu" still readable and have 45 degree with X-axis. Below is my code:

CGContextSelectFont(context, "Arial", 12, kCGEncodingMacRoman);
CGContextSetTextDrawingMode(context, kCGTextFill);

CGContextSetRGBFillColor(context, 0, 0, 0, 1); // 6 
CGContextSetRGBStrokeColor(context, 0, 0, 0, 1);

CGContextSetTextMatrix(context, CGAffineTransformMake(1.0,0.0, 0.0, -1.0, 0.0, 0.0));   
CGContextSetTextMatrix(context, CGAffineTransformMakeRotation(45)); 
CGContextShowTextAtPoint(context,10, 10, "Menu", 4);

Best Answer

CGAffineTransformMakeRotation expects angle in radians, not in degrees. 

#define DEGREES_TO_RADIANS(x) (M_PI * (x) / 180.0)
...

CGAffineTransformMakeRotation(DEGREES_TO_RADIANS(45));
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