Re: NSImage > trapezium...

FROM : glenn andreas
DATE : Sun Mar 23 15:10:14 2008

On Mar 23, 2008, at 8:54 AM, Cathy Shive wrote:
> On Mar 23, 2008, at 2:14 PM, Luca wrote:
>

>> Hello. Do you know how can I transform a rectangular image in a 
>> trapezium?

>
> Seriously?
>
> You aren't going to be able to distort your bitmap like this with 
> NSImage and there is no ready-made CIFilter to do this distortion 
> that I'm aware of.  If I'm wrong about that, then that's the way to 
> go.  But,  I think you've gotta do your own pixel pushing for this 
> one.
>


Actually, the CIPerspectiveTransform will do this perfectly (you even 
just give it the resulting four corner points)

You can't do that will an affine transform though (since perspective 
is, by definition, non-affine), so you'll need to use CoreImage.


Glenn Andreas                      <email_removed>
  <http://www.gandreas.com/> wicked fun!
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