Skewing An Image

Hi,

Total OpenGL user here, I am trying to use it in an iPhone project. Basically I want to let a user skew an image.

I’ve followed the tutorial from here:

http://iphonedevelopment.blogspot.com/2009/05/opengl-es-from-ground-up-part-6_25.html

and get:

which converts to:

How can I get it to skew without the fold in the middle?

I’m guessing it’s due to GL_TRIANGLE_STRIP, but not sure what approach to take next. Do I make a lot of small triangles or is there an easy way?

Thanks

Have a read on this :
http://xyzw.us/~cass/qcoord/