Blender Git Loki

Merge branch 'master' into blender2.8

Fix T52299: X resolution of 4 causes nodes to collapse

Was caused by numeric overflow when calculating preview dimensions.
Now we try to avoid really insance preview resolutions by fitting
aspect into square.

Eevee: SSR: Making ray count a define rather than an uniform.

The branching introduced by the uniform caused problems on mesa + AMD in the resolve stage.
This patch create one shader per sample count without branching.
This improves performance of a single ray per pixel case (3.0ms against 3.6ms in my testing)

Code cleanup: store branch factor in PathState.

Code cleanup: avoid used of uninitialized value in case of precision issue.

Code cleanup: abstract shadow catcher logic more into accumulation code.

Code cleanup: deduplicate some branched and split kernel code.

Benchmarks peformance on GTX 1080 and RX 480 on Linux is the same for
bmw27, classroom, pabellon, and about 2% faster on fishy_cat and koro.

Code cleanup: tweak inlining for 2% better CUDA performance with hair.

Workspace/Engine: Create BKE_render_* calls equivalent to BKE_scene_*

Fix T52140: Align objects centers using origin for text

The issue was caused by operator redo which frees all object's evaluated data,
including bounding box. This bounding box can not be reconstructed properly
without full curve evaluation (need to at least convert font to nurbs, which is
not cheap already).

Cleanup: avoid right-shifted args in RNA register

Node UI: scale cross by pixelsize

Draws a little smaller to fit with 2.8x manipulator.

Manipulator: cage2d option to grab w/ a center handle

Fix T52113: Compositor doesnt mix unrendered render layers well

Compositor was always defaulting to all-zero s output for missing passes.

This was broken in 4cf7fc3.

Compositor: Cleanup, get rid of nested ternary operators

Having single switch statement is much more readable.

Compositor: Cleanup, de-duplicate some code

Compositor: Cleanup, reduce indentation level in render layer node

There is absolute no reason to have such an indentation level, it only causes
readability and maintainability issues. It is really simple to make code more
"streamlined".

Fix UI compatibility to use context.engine

Use workspace engine for draw manager "render preview"

Add basic addition support to create new assets.

Again, very basic and limited, to be fleshed out later.