Change Perspective / Deform an UIImage, possible solutions?

[Dvdkite]

Hi Guys,

I'm actually working on a solution for this problem.
I would like to change the perspective of an UIImage with a finger touch on the corner of interest. This image will explane exactly what I want:



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The best thing could be to give the possibilities to replicate the same function as photoschop (ctrl + T and then hold CTRL and you can deform the image from any corner).
Is there any easy way to do this? Is there any ways(function to provides the coordinates of the four corner points and let it deform/change the perspective of an UIImage?

A normal Frame is a rectangle (rect). Can you set a frame with something that is not a RECT but a sort of "shape" identified by the 4 corner points of an UIImage?

I actually have no idea about create a funtion able to do such transform.

Any help , suggestion or link will be appreciated!
I'll post my search result here.

Thanks ,

David

[nobre84]

Study Affine Transformations, what you want is called shearing... It doesn't have built-in functions in the sdk (it does for scaling, rotation, etc), but is easily doable creating one with CGAffineTransformMake with the correct coefficients

Take a look at this: iPhone Development: CGAffineTransform 1.1 - A little more

[Dvdkite]

Originally Posted by nobre84

Study Affine Transformations, what you want is called shearing... It doesn't have built-in functions in the sdk (it does for scaling, rotation, etc), but is easily doable creating one with CGAffineTransformMake with the correct coefficients

Take a look at this: iPhone Development: CGAffineTransform 1.1 - A little more

Thank you very much!
I'll play with it next days and I'll write here my impression!!

Thanks again!!!

David