Hi Agha,

I'm not too sure what's wrong with the picture so I'm not sure how much I can help you.

But to rotate your image by the centre, first translate your image or context so the centre of the image/context is located at the origin:
1 Translate by negative half width, negative half height,
2 Rotate by theta degrees,
3 Translate by positive half width, positive half height to undo the first transform.

Maybe this helps?

Kiel

On 13/08/2009, at 12:03 PM, Agha Khan wrote:

I have 6 small images which should be rotated in a view. Picture worth 1000 words.


        transform = CGAffineTransformMakeTranslation(0.0, 20);
        transform = CGAffineTransformRotate(transform, M_PI);
        //      transform = CGAffineTransformScale(transform,1, -1);
                
        CGContextConcatCTM(ctx, transform);
                
                
                DigFileName = [NSString stringWithFormat:@"n%d.png",Edges[3]];
                img = [UIImage imageNamed:DigFileName];
                CGContextDrawImage(ctx, CGRectMake(8, 38, 20, 20), img.CGImage);

Because I am rotating the leftside image should be flipped. I know it is wrong and showed you just to explain. I am confused because I want to rotate the image of the center of the image. I am not sure how to rotate image at the center.

Thank you for prompt reply.

Best regards
Agha<Picture 16.png>

On Aug 12, 2009, at 6:49 PM, Kiel Gillard wrote:

Hi Agha,

An appropriate answer depends entirely on what you want to do with the image. Do you want to draw the image into a view? Do you want to save the image to the hard disk?

You'll have to give us more information to help you out.

Kiel

On 13/08/2009, at 11:22 AM, Agha Khan wrote:

HI:
Can someone point me the sample code for image transformation?
You help will be very much appreciated.
Best regards
Agha Khan
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