Blender Git Loki

Splash: add first time setup and templates to splash screen.

The first time setup screen only has the interaction preset currently, some
more work is needed to be able to set e.g. the language or compute device
here as in the mockups.

The splash screen stayed the same for now, to make room for the templates
most of the links are now in the Help menu. If there are no recent files yet
the links still show.

The splash screen buttons implementation was fully moved to Python, in the
WM_MT_splash menu.

Workspaces: move 2D Animation, VFX and Video workspaces into own templates.

These can now be acessed from the File > New, Ctrl+N, or the splash screen.
Since these are application templates, users can save a separate startup.blend
for each. User preferences are shared between these templates though.

This also fixes some issues in the default startup.blend (triangulated cube..).

Differential Revision: https://developer.blender.org/D3690

Application Templates: make templates more prominent in the UI.

The goal here is to make app templates usable for default templates
that we can ship with Blender. These only have a custom startup.blend
currently and so are quite limited compared to app templates that fully
customize Blender.

But still it seems like the same kind of concept where we should be
sharing the code and UI. It is useful to be able to save a startup.blend
per template, and I can imagine some scripting being useful in the future
as well.

Changes made:

* File > New and Ctrl+N now list the templates, replacing a separate
Application Templates menu that was not as easy to discover.
* File menu now shows name of active template above Save Startup File
and Load Factory Settings to indicate these are saved/loaded per
template.
* The "Default" template was renamed to "General".
* Workspaces can now be added from any of the template startup.blend
files when clicking the (+) button in the topbar.

* User preferences are now fully shared between app templates, unless
the template includes a custom userpref.blend. I think this will be
useful in general, not all app templates need their own keymaps for
example.
* Previously Save User Preferences would save the current app template
and then Blender would start using that template by default. I've
disabled this, to me it seems it was unintentional, or at least not
clear at all that saving user preferences also makes the current

Differential Revision: https://developer.blender.org/D3690

UI: don't show Redo Unsupported, just hide buttons in that case.

GP: Change isolate layer icon

Subdiv: CCG, implement stitching of given faces

Will speed up (or rather bring speed back to what it is supposed to be)
for brushes like smooth.

Subdiv: CCG, make inner face grids averaging more reusable

Subdiv: CCG, initial grids stitching implementation

Currently is only working on an "inner" grid boundaries.
Need to implement averaging across face edges.

Subdiv: CCG, evaluate final position for multires

This makes it so coordinates and normals for CCG are calculated
with mutires displacement taken into account. This solves issues
with multires displacement being lost when entering sculpt mode.

The missing part is averaging of normals along grid boundaries.
But even then sculpting shows decent results.

The plan to solve that would be to introduce function to stitch
grids, which can also be used by Smooth brush which requires
this.

Merge branch 'master' into blender2.8

Fix T56833: "zoom to cursor" in Clip editor not handling aspect ratio.

Trivial fix, just using same code as in Image editor...

GPUShader: Manually validate sampler count

This happens on NVidia GPUs, using more textures than the maximum allowed
by the gl will NOT trigger a linking issue (maybe because of bindless
texture implementation?).

So in this case we manually count the number of samplers per shader stage
and compare it against the GL limit. We discard the shader if the sampler
count is too high. This shows the user something is wrong with the shader.

Support evaluating simple driver expressions without Python interpreter.

Recently @sergey found that hard-coding evaluation of certain very
common driver expressions without calling the Python interpreter
produces a 30-40% performance improvement. Since hard-coding is
obviously not suitable for production, I implemented a proper
parser and interpreter for simple arithmetic expressions in C.

The evaluator supports +, -, *, /, (), ==, !=, <, <=, >, >=,
and, or, not, ternary if; driver variables, frame, pi, True, False,
and a subset of standard math functions that seem most useful.

Booleans are represented as numbers, since within the supported
operation set it seems to be impossible to distinguish True/False
from 1.0/0.0. Boolean operations properly implement lazy evaluation
with jumps, and comparisons support chaining like 'a < b < c...'.

Expressions are parsed into a very simple stack machine program
that can then be safely evaluated in multiple threads.

Reviewers: sergey, campbellbarton

Differential Revision: https://developer.blender.org/D3698

CMake: remove PYTHON_NUMPY_INCLUDE_DIRS as a cache variable on macOS/Windows.

It's in a fixed location on those platforms, and having it as a cache variable
just means things break when we upgrade to a new Python version.

UI: use monochrome lock icons next to decorators.

Merge branch 'master' into blender2.8

Close OpenEXR thread pool on exit

This partially solves ASAN report about unfreed memory. There is still
something in the report, need to have a closer look with debug version
of OpenEXE library.

Fix T56831: Crash - Transfer Weight & changing it's properties.

Usual Undo/Redo case with operators needing evaluated data...

Cleanup: spelling

Gizmo: de-duplicate poll logic

Checking the active tool or operator was a common way to check
if the gizmo was still in use.