Recording

Gem window

Here [pix_record] will be used to make a simple animation of png images (including transparency).

The patch might look a bit complicated but basically:

- the top quarter allows to create a Gem window and import Gem and cyclone/counter

- the lower-right part will mix two pictures at a certain rate given by the [metro] object

- the lower-left part will trigger recoding through [pix_record]

Note that pix_record can (at the time of writing) only record one pix chain - you cannot save a texture projected on a geometry (try with a [cube] for example).