Blender Git Loki

Fix T78608: Memory leak in Material properties: "Data from SCE".

Caused by recent own refactor of cache presevation handling in readfile,
EEVEE's lightcache are weird birds that can also be saved in .blend
files, need a special handling for those 'persistent' caches...

Cleanup: warning, spelling

Docs: reference bl_rna_get_subclass_py instead of bl_rna_get_subclass

bl_rna_get_subclass only works for Nodes at the moment.

Fix alignment/size issue on ARM/RPi architecture

Addresses 964305 from Debian bug tracker.

Optimization: Don't compute the snap to face on the knife tool twice

Both `knife_find_closest_vert` and `knife_find_closest_edge` call
`knife_find_closest_face`. Thus, running the raycast twice and setting
values like `kcd->curr.bmface` and `kcd->curr.is_space` repeatedly.

So:
- separate `knife_find_closest_face` from `knife_find_closest_vert` and `knife_find_closest_edge`.
- rename `knife_find_closest_vert` to `knife_find_closest_vert_of_face`
- rename `knife_find_closest_edge `to `knife_find_closest_edge_of_face`.
- do not set parameters previously set.

Differential Revision: https://developer.blender.org/D8198

Fix faces disappearing when AutoMerge & Split

Fix UV select separate not refreshing the display

UV: add rip region to toolbar

Cleanup: spelling, comments

Cleanup: rename namespace TimeIt to timeit

According to our style guide, namespaces should have
lower case names.

Use short for tot_col: total materials in an object.

Grammar fixes in comments.

BLI: refactor how buffers for small object optimization are stored

Previously, there was an error when operator-> was returning an
invalid type. See error C2839.

Merge branch 'master' into soc-2020-io-performance

Support modifiers' render and viewport properties

UV: add rip tool

New rip tool matching edit-mesh rip functionality.

Useful as disconnecting UV's, especially for loops is inconvenient
without this.

This uses 'V' to rip, changing stitch to 'Alt-V'.

BMesh: add BM_face_calc_uv_cross

BMesh: add BM_loop_other_vert_loop_by_edge

Fix T78481: Workbench Shadow effects XRay

When in XRay some effects (shadow, cavity & depth of field) aren't supported.
This patch makes sure that these effects aren't enabled.

Cleanup: warnings, spelling