Blender Git Loki

Multires: Fix ownership problem causing crashes

Fixes crash when leaving multires mode.

Fixes T61836: Saving while in multires makes blender crash

Revert "makesrna: Fix build error on windows."

This reverts commit 8b235dd2e3995a61e2a7db1ac2bc9eefe1394456.

C logging: make pthread use optional

There is no need for threading for makesrna/makesdna,
disable it to avoid hassles linking build time utilities.

Cleanup: function wrapping, spelling

Comments: add doxy sections to readfile.c

Some minor changes to arrange code into useful sections too.

readfile: support blend files over 2gb

Should work for 4gb+ files too however I wasn't able to test that.

readfile: reduce memory usage at load time

Delay loading all DATA sections of the blend file until they're needed.

Loading all data-blocks caused high peak memory usage especially with
libraries - since a lot of data may exist which isn't used directly.

In one test (spring project: 10_010_A.anim.blend),
peaked at ~12.5gig, dropping back to ~2.5gig once loaded.
With this change peaks memory usage reaches ~2.7gig while loading.

Besides this there are some minor gains from not having to read data
from the file-system and we can skip an alloc + memcpy reading data
written with the same version of Blender.

Cleanup: rename seek to file_offset

Prepare for seek callback to be added.

Sculpt Overlay: Fix mask drawn as flat shaded when smooth shading enabled

Removes the flat shader variant since the attrib is specified for each vert
loop in flat shaded mode. It was something leftover from the previous
implementation.

GPUBuffers: Fix/cleanup multires implementation

The multires sculpt drawing was a not working in smooth mode.
Also hidding was not supported by the wireframe overlay and flat shaded
faces.

Codewise it is cleaner and index buffers are only updated if the
smoothing changes.

Cleanup: make BHeadN private in readfile.c

Also add macro for accessing BHeadN from BHead.

Missed last commit

Harmless but not renamed as intended.

Cleanup: rename readfile API functions

- blo_bhead_first (was blo_firstbhead)
- blo_bhead_next (was blo_nextbhead)
- blo_bhead_prev (was blo_prevbhead)
- blo_bhead_id_name (was bhead_id_name)
- blo_filedata_free (was blo_freefiledata)
- blo_filedata_from_file (was blo_openblenderfile)
- blo_filedata_from_memory (was blo_openblendermemory)
- blo_filedata_from_memfile (was blo_openblendermemory)

Missed last commit

Cleanup: comments, use bool for 'eof' variable

Also remove unused members headerdone, inbuffer & filedes,
use typed enum for file data flags.

Transform: redo resize now constrains axis values

Before 1bfbfa281046b this wasn't essential because the constraints
prevented the axes from being applied.

Now redo ignores constraints - the input values must be constrained.

makesrna: Remove usage of dynamically linked pthreads4w

With pthreads now being static, there is no more reason to copy the dll.

Windows: Use static pthreads library.

Windows: Use static pthreads library.

UI: enum property menus now expand down, consistent with other menus.

Differential Revision: https://developer.blender.org/D4359