Blender Git Loki

Manipulator: target property definitions

Changes from custom-manipulator branch.

- use property type definitions.
- add property free callback.
- move properties into the wmManipulator struct (over alloc).
- use array length from property types instead of arg passing.

Fix T51867: Insert Keyframe I - L / I - R / I - S key combos are broken.

Reorder keyingsets registration order, since it also afects order of I
menu options, better show most used ones first, pure alphabetical order
is not great here... Will likely break some muscle memory though. :|

Based on D2720 by Carlo Andreacchio (@candreacchio), thanks.

Fix T51863: CompositorNodeSwitchView have the wrong rna API

Although the original report was about the docs, the real issue was in
the API.

My original commit started from a copy-paste from the Switch
Node. However I don't use custom1 for thew Switch View node.

The docs is slightly incomplete since it would be nice to mention the
views here. Or maybe even expose them via Python. But honestly they are
generated depending on the scene multi-view settings.

Eevee: Ambient Occlusion: Enable Multibounce approximation and Change influence factor.

Making the influence a power for easy tuning. Works like a contrast knob.

Eevee: Ambient Occlusion: Initial implementation.

Implement GTAO (Ground Truth Ambient Occlusion) which is a special case of Horizon Based Ambient Occlusion that is more physically accurate.
Also add a bent normal option to sample indirect irradiance (diffuse lighting) with the least occluded direction.

Eevee: Improve material variation managment.

- Unify variations between default shaders and material shader.
- Only create default shader passes if needed.

Downside is that we have a big array of passes and shading grp in the vedata ... And it will double in size each time a new variation flag is added.

Eevee: Ambient Occlusion: Add UI properties.

Eevee: Minmax Depth Pyramid.

This commit introduce the computation of a depth pyramid containing min and max depth values of the original depth buffer.
This is useful for Clustered Light Culling but also for raytracing on the depth buffer (SSR).
It's also usefull to have to fetch higher mips in order to improve texture cache usage.

As of now, 1st mip (highest res) is half the resolution of the depth buffer, but everything is already done to be able to make a fullres copy of the depth buffer in the 1st mip instead of downsampling.
Also, the texture used is RG_32F which is a too much but enough to cover the 24bits of the depth buffer. Reducing the texture size would make things quite faster.

GPUFramebuffer: Add recursive downsampling function.

This special case function enables rendering to a miplevel while using the miplevels above as texture input.
This is needed for some algorithm (i.e. creating a min-max depth pyramid texture).

GPUTexture: Support for nearest sampling with mipmaps.

Cycles: Fix excessive sampling weight of glossy Principled BSDF components

If there was any specularity in the Principled BSDF, it would get a sampling
weight of one regardless of its actual impact.

This commit makes Cycles estimate the contribution of the component and adjust
the weighting accordingly, which greatly improves the noise characteristics of
the Principled BSDF in many cases.

Note that this commit might slightly change the brightness of areas when using
MultiGGX and high roughnesses, but the new brightness is more accurate and
closer to the result of Branched Path Tracing. See T51836 for details.

Differential Revision: https://developer.blender.org/D2677

Fix T51836: Cycles: Fix incorrect PDF approximations of the MultiGGX closures

The PDF of the MultiGGX sampling is approximated by the singlescattering GGX
term as well as a scaled diffuse term that makes up for the energy in the
multiscattering component that's missed by GGX.

However, there were two problems with the glossy terms: The diffuse term missed
a normalization factor, and the singlescattering term was not properly scaled
down based on the albedo estimate.

The glass term was completely wrong and has been rewritten. It uses the fresnel
factor to weight reflection vs. refraction and uses the glossy MultiGGX model
for reflection.
For refraction, the correct singlescattering term is now used, and a new
albedo approximation is used that was derived by evaluating GGX albedo for
roughnesses from 0 to 1 and IORs from 1 to 3 and fitting numerical
approximations to it. The resulting model has a mean relative error of 9e-5,
but could probably be simplified without losing noticable accuracy in the
final render.

The improved PDFs help with glossy highlights (due to better light sampling vs.
closure sampling MIS) and fix the situation described in T51836 where mixing
MultiGGX with other closures (as it happens in e.g. the Principled
BSDF) causes incorrect darkening.

Fix T51862: principled shader GLSL artifacts in ortho mode.

Fix T51849: change Cycles clearcoat gloss to roughness.

This is compatible with UE4 and more consistent with specular and transmission
roughness, even if it deviates from the original Disney BRDF.

Merge remote-tracking branch 'origin/master' into blender2.8

Fix typo in builtbot config

Fix blenderplayer (tm)

Fix T51856: `BKE_mesh_new_from_object()` would often generate default 'Mesh' named datablock.

This is annoying especially for exporters who do use mesh name, since it
broke any relation with actual Mesh naming in original Blend file.

Unfortunately, we cannot avoid the extra .xxx digits. ;)

Manipulator: edit_properties -> target_properties

Naming was too confusing between properties of a manipulator
and properties it edits.

Manipulator: Move types into their own directory