Blender Git Loki

Icons: update to r62155

- Tweaked GP toolbar icons and added Line, Rectangle & Circle.
- Added the remaining toolbar icons for all our paint & sculpt modes.
- Made all the toolbar icons the same simple style.

Cleanup: de-duplicate poll function

Tool System: add grease pencil primitive tool

UI: Decrease the fade in/out time of regions with region overlap on.

UI: tweak object type active state

The state of the objects visibility should only impact
the 'active' display of the select icon, not it's self.

Cleanup: use proportional edit template for keymap

Cleanup: use tuple instead of dict

This just loops over pairs so no mapping is needed.

UI: Tweaks to Object Types Visibility popover.

Replace checkbox for visibility with eye icon instead.
Thanks a.monti and zebus3d for the help.

Closes T57714
Part of UI Paper Cuts T56950

Cleanup: de-duplicate keymap items

UI: Name added LightProbe objects after their type.

Just like Light objects do.

Thanks ThinkingPolygons from DevTalk forums for suggesting this!

See T56950

readme: remove 'game creation'.

Merge branch 'master' into blender2.8

readme: use name 'macOS'

Keymap: skip loading the keymap preset in background mode

Caused a crash on exit and isn't needed.

Keymap: move builtin keymaps from C to Python

This should be purely an implementation change,
for end users there should be no functional difference.

The entire key configuration is in one file with ~5000 lines of code.
Mostly avoiding code duplication and preserve comments and utility
functions from the C code.
It's a bit long but for searching and editing it's also convenient to
have it all in one file.

Notes:

- Actual keymap is shared by blender / blender_legacy
and stored in `keymap_data/blender_default.py`

This only generates JSON-like data to be passed into
`keyconfig_import_from_data`, allowing other presets to load and
manipulate the default keymap.

- Each preset defines 'keyconfig_data'
which can be shared between presets.

- Some of the utility functions for generating keymap items still
need to be ported over to Python.

- Some keymap items can be made into loops (marked as TODO).

See: D3907

Eevee: Fix broken Vector Transform node

The Camera to Object space matrix was not implemented in gpu_codegen.

Eevee: Add partial support for the Light Path Node

This makes it possible to tweak indirect lighting in the shader.

Only a subset of the outputs is supported and the ray depth has not exactly
the same meaning:

Is Camera : Supported.
Is Shadow : Supported.
Is Diffuse : Supported.
Is Glossy : Supported.
Is Singular : Not supported. Same as Is Glossy.
Is Reflection : Not supported. Same as Is Glossy.
Is Transmission : Not supported. Same as Is Glossy.
Ray Length : Not supported. Defaults to 1.0.
Ray Depth : Indicate the current bounce when baking the light cache.
Diffuse Depth : Same as Ray Depth but only when baking diffuse light.
Glossy Depth : Same as Ray Depth but only when baking specular light.
Transparent Depth : Not supported. Defaults to 0.
Transmission Depth : Not supported. Same as Glossy Depth.

Caveat: Is Glossy does not work with Screen Space Reflections but does work
with reflection planes (when used with SSR or not).
We have to render the world twice for that to work.

Eevee: Fix geometry node for environments and support true_normal

Also minor cleanup for the Bump node.

Eevee: Fix refraction materials

Fix refraction depth not working without ScreenSpace Refraction.
Fix ScreenSpace Refraction masking reflections.

Fix wrong selectability icon in viewport menu.