bug fix
update openfx
Engine: fix static analysis issues
ViewerGL: fix dark borders on the four sides of the texture
Viewer: don’t refresh texture if RoI has changed
Lock the texture before calling renderRoI
Don’t allow tracking outside of frame range
Adjust int sliders
Same for timeline
Bug fix: don’t pass the wrong rectangle to tiledRenderingFunctor if
node doesn’t support the render scale.

Also start implementing the trimap support. Just set
NATRON_ENABLE_TRIMAP  1 in Global/Macros.h
The implementation is not finished.

Also add 2 warnings in Bitmap:minimalNonMarkedRects for suspicious
behaviour
Be more tolerant when checking fps issues, don’t  warn for  differences
under 0.01 fps
Experimental trimap support: used only for non-abortable renders
Fix unit tests
Trimap: halveRoI: consider pixels of the bitmap with the value of 2 as
pixels 0

Viewer: zoom & pan renders cannot abort
ops
waitForImageBeingRenderedElsewhereAndUnmark some bug fixes.
+ Fix deadlock
+ Viewer: frame range & fps label are clickable
+ Better node render hints
Viewer: separate the cache look-up from the rendering so that the
viewer is always responsive if all the thread-pool is busy.

Disable trimap temporarily because of deadlocks
trimap: fix deadlock, set the flag back to false
trimap: bug fix , we were not always waiting for concurrent renders if
isBeingRenderedElsewhere was true