* Compo node backdrop works again.
* Compo node previews and backdrop now get correct color management
float to byte conversion.
* Compo nodes got unecessarily recalculated while moving nodes.
* Fix compo node viewer nodes not getting activated correctly.
* Main compo node preview render computations are now outside of
mutex lock, so better for multithreading.
* Tex node outputs did not work in some files loaded from 2.4.
* Change RNA updates to take into account groups that may be shared
between multiple node trees.
* Rendering twice or more could crash layer/pass buttons.
* Compositing would crash while drawing the image.
* Rendering animations could also crash drawing the image.
* Compositing could crash
* Starting to rendering while preview render / compo was
still running could crash.
* Exiting while rendering an animation would not abort the
renderer properly, making Blender seemingly freeze.
* Fixes theoretically possible issue with setting malloc
lock with nested threads.
* Drawing previews inside nodes could crash when those nodes
were being rendered at the same time.
There's more crashes, manipulating the scene data or undo can
still crash, this commit only focuses on making sure the image
buffer and render result access is thread safe.
Implementation:
* Rather than assuming the render result does not get freed
during render, which seems to be quite difficult to do given
that e.g. the compositor is allowed to change the size of
the buffer or output different passes, the render result is
now protected with a read/write mutex.
* The read/write mutex allows multiple readers (and pixel
writers) at the same time, but only allows one writer to
manipulate the data structure.
* Added BKE_image_acquire_ibuf/BKE_image_release_ibuf to access
images being rendered, cases where this is not needed (most
code) can still use BKE_image_get_ibuf.
* The job manager now allows only one rendering job at the same
time, rather than the G.rendering check which was not reliable.
Added RGB space distance matte Node
Added HSV color matte Node
Fixed Image difference matte Node to use image differences instead of RGB space distance
Fixed luminance node for low end values being read wrong
Fixed CMP_util copy/swap functions not accounting for all channels
Fixed UI for difference matte Node
Added RNA for new nodes
Compositor:
Muting option to temporary disable/enable nodes.
Hotkey: press M on selection. It toggles.
Note: no menu entry yet, and drawing style could be tweakered...
a premul image but that doesn't work correct. Now it depremuls and
premuls again around the gamma correction. Better solution might be
possible, but this gives compatible results.
Crashes in composite; caused by bad bad bug in freeing "passed on" buffers,
only happens with option "Free unused" set though.
Appeared to be mixup of variable names. Code changes with 2 bytes... :)
