cornerpin / keystoning of data

Torsten Lauschmann's icon

Its simple but I cant get my head around it:
I try to do the classic cornerpin / keystoning of a skewed
rectangular (projection). Instead of skewing video I want incoming
x,y values to be mapped to the new skewed rectangular.
Does that make sense?
Can anyone direct me into the right direction?
Cheers
Torsten

Rob Ramirez's icon

corner pinning is not exactly simple.

here is a patch using gl.nurbs to get you started. you could also use gl.mesh. basic idea is to adjust the celss of a 2x2 matrix to move your corners.

a simple "corner pin" search will turn up a few other techniques.

Max Patch
Copy patch and select New From Clipboard in Max.

Torsten Lauschmann's icon

Thanks a lot for the quick help,
is there any chance to get a patch which works in 4.6?
All the best
Torsten

Rob Ramirez's icon

here's the sreenshot. should be all you need.

Torsten Lauschmann's icon

thank you, will give it a try.

Torsten Lauschmann's icon

Thats great, I made the patch and it does exactly what I meant with a video texture. I wonder if there is any way to send a x,y coordinate (position) of a matrix to the jit.gl.nurbs and get the altered "nurbed" x,y position.
Cheers
Torsten

outoff's icon
Torsten Lauschmann's icon

Cheers, do you have a screenshot or 4.6 patch of that link?
Cheers
Torsten

outoff's icon

May be somebody can convert it to 4.6 ?
Hope it helps!

outoff's icon

another one

Torsten Lauschmann's icon

thanks a lot

DiGiTaLFX's icon

Hello

I have just been experimenting with corner pinning this evening, and would really appreciate it if someone could explain the difference between using nurbs as in this example, compared to a mesh as discussed here: https://cycling74.com/forums/corner-pin-adjustement-of-planequad-with-videotexture

I notice that there isn't a need to scale the control matrix bigger than 2x2 as there is with the mesh, so is it simply that nurbs take care of themselves with regards to mapping properly? Is the outcome mapped identically?

Many thanks

DiGiTaLFX

FP's icon

effectively it seems you don't need more than a matrix 2x2 with jit.gl.nurbs

DiGiTaLFX's icon

Brilliant, thanks for the response :)