i'd like to create a mask with a hole that let only a part of a qt.movie 

be able to move that mask position on the video, and *draw* with that piece

moving a gl object -say a circle- with (*on?*) a texture and putting

the render output in a matrix...pretty heavy solution

I tried to extract a small part of the video with jit.submatrix, but

then I didn't find any way to insert that submatrix in a bigger one

at a specific position (could it be a feature of jit.fill to aslo accept

matrix of a smaller or equal size than the filled matrix?)

Is there any shader/slab capable of doing that?

i'd like to create a mask with a hole that let only a part of a qt.movie 
appear,
be able to move that mask position on the video, and *draw* with that piece
of video to feed a texture.
- 1st solution:
moving a gl object -say a circle- with (*on?*) a texture and putting
the render output in a matrix...pretty heavy solution
- 2 solution:
I tried to extract a small part of the video with jit.submatrix, but
then I didn't find any way to insert that submatrix in a bigger one
at a specific position (could it be a feature of jit.fill to aslo accept
matrix of a smaller or equal size than the filled matrix?)

-3rd solution??
Is there any shader/slab capable of doing that?

mask-over-a-qt-movie

alpha channels in the matrix being drawn by the jit.qt.videoplane 

alpha channels in the matrix being drawn by the jit.qt.videoplane  
with @blend_enable 1.


there's also the quick 'n' dirty jit.lcd. see the help file on 

overlaying lcd-generated graphics over a jitter video matrix.

there's also this nifty thing I cooked up:

there's also the quick 'n' dirty jit.lcd.  see the help file on 
overlaying lcd-generated graphics over a jitter video matrix.
there's also this nifty thing I cooked up:

mask over a qt.movie