User notes
----------
Compositing, rendering of multi-layers in Eevee should be fully working now.
Development notes
-----------------
Up until now we were still using the same depsgraph for rendering and viewport
evaluation. And we had to go out of our ways to be sure the depsgraphs were
updated.
Now we iterate over the (to be rendered) view layers and create a depsgraph to
each one, fully evaluated and call the render engines (Cycles, Eevee, ...) with
this viewlayer/depsgraph/evaluation context.
At this time we are not handling data persistency, Depsgraph is created from
scratch prior to rendering each frame. So I got rid of most of the partial
update calls we had during the render pipeline.
Cycles: Brecht Van Lommel did a patch to tackle some of the required Cycles
changes but this commit mark these changes as TODOs. Basically Cycles needs to
render one layer at a time.
Reviewers: sergey, brecht
Differential Revision: https://developer.blender.org/D3073
- Use BLI_threadpool_ prefix for (deprecated)
thread/listbase API.
- Use BLI_thread as prefix for other functions.
See P614 to apply instead of manually resolving conflicts.
Now all the fine-tuning is happening using parallel range settings structure,
which avoid passing long lists of arguments, allows extend fine-tuning further,
avoid having lots of various functions which basically does the same thing.
Since we are ditching layers from Blender (2.8) we need a replacement to
control groups visibility. This commit introduces collections as the building
blocks for groups, allowing users to control visibility as well as overrides
for groups.
Features
========
* Groups now have collections
This way you can change the visibility of a collection inside a group, and add
overrides which are part of the group and are prioritized over other overrides.
* Outliner
Groups can inspect their collections, change visibility, and add/remove members.
To change an override of a group collection, you need to select an instance of
the group, and then you can choose "group" in the collection properties editor
to edit this group active collection instead of the view layer one.
* Dupli groups overrides
We can now have multiple instances of the same group with an original "override"
and different overrides depending on the collection the instanced object is part
of.
Technical
=========
* Layers
We use the same api for groups and scene as much as possible.
Reviewers: sergey (depsgraph), mont29 (read/write and user count)
Differential Revision: https://developer.blender.org/D2892
The RenderResult struct still has a listbase of RenderLayer, but that's ok
since this is strictly for rendering.
* Subversion bump (to 2.80.2)
* DNA low level doversion (renames) - only for .blend created since 2.80 started
Note: We can't use DNA_struct_elem_find or get file version in init_structDNA,
so we are manually iterating over the array of the SDNA elements instead.
Note 2: This doversion change with renames can be reverted in a few months. But
so far it's required for 2.8 files created between October 2016 and now.
Reviewers: campbellbarton, sergey
Differential Revision: https://developer.blender.org/D2927
2.8x branch added bContext arg in many places,
pass eval-context instead since its not simple to reason about what
what nested functions do when they can access and change almost anything.
Also use const to prevent unexpected modifications.
This fixes crash loading files with shadows,
since off-screen buffers use a NULL context for rendering.
We do have an history of those pieces of evil in our code, would be nice
to get fully rid of it, but at the very least let's not add more of them
in new code. :)
Note that some little parts of code have been dissabled because eval_ctx
was not available there. This should be resolved once DerivedMesh is
replaced.
Design Documents
----------------
* https://wiki.blender.org/index.php/Dev:2.8/Source/Layers
* https://wiki.blender.org/index.php/Dev:2.8/Source/DataDesignRevised
User Commit Log
---------------
* New Layer and Collection system to replace render layers and viewport layers.
* A layer is a set of collections of objects (and their drawing options) required for specific tasks.
* A collection is a set of objects, equivalent of the old layers in Blender. A collection can be shared across multiple layers.
* All Scenes have a master collection that all other collections are children of.
* New collection "context" tab (in Properties Editor)
* New temporary viewport "collections" panel to control per-collection
visibility
Missing User Features
---------------------
* Collection "Filter"
Option to add objects based on their names
* Collection Manager operators
The existing buttons are placeholders
* Collection Manager drawing
The editor main region is empty
* Collection Override
* Per-Collection engine settings
This will come as a separate commit, as part of the clay-engine branch
Dev Commit Log
--------------
* New DNA file (DNA_layer_types.h) with the new structs
We are replacing Base by a new extended Base while keeping it backward
compatible with some legacy settings (i.e., lay, flag_legacy).
Renamed all Base to BaseLegacy to make it clear the areas of code that
still need to be converted
Note: manual changes were required on - deg_builder_nodes.h, rna_object.c, KX_Light.cpp
* Unittesting for main syncronization requirements
- read, write, add/copy/remove objects, copy scene, collection
link/unlinking, context)
* New Editor: Collection Manager
Based on patch by Julian Eisel
This is extracted from the layer-manager branch. With the following changes:
- Renamed references of layer manager to collections manager
- I doesn't include the editors/space_collections/ draw and util files
- The drawing code itself will be implemented separately by Julian
* Base / Object:
A little note about them. Original Blender code would try to keep them
in sync through the code, juggling flags back and forth. This will now
be handled by Depsgraph, keeping Object and Bases more separated
throughout the non-rendering code.
Scene.base is being cleared in doversion, and the old viewport drawing
code was poorly converted to use the new bases while the new viewport
code doesn't get merged and replace the old one.
Python API Changes
------------------
```
- scene.layers
+ # no longer exists
- scene.objects
+ scene.scene_layers.active.objects
- scene.objects.active
+ scene.render_layers.active.objects.active
- bpy.context.scene.objects.link()
+ bpy.context.scene_collection.objects.link()
- bpy_extras.object_utils.object_data_add(context, obdata, operator=None, use_active_layer=True, name=None)
+ bpy_extras.object_utils.object_data_add(context, obdata, operator=None, name=None)
- bpy.context.object.select
+ bpy.context.object.select = True
+ bpy.context.object.select = False
+ bpy.context.object.select_get()
+ bpy.context.object.select_set(action='SELECT')
+ bpy.context.object.select_set(action='DESELECT')
-AddObjectHelper.layers
+ # no longer exists
```
Things like `BLI_uniquename` had nothing, but really nothing to do in
BLI_path_util files!
Also, got rid of length limitation in `BLI_uniquename_cb`, we can use
alloca here to avoid overhead of malloc while keeping free size (within
reasonable limits of course).
It is quite likely in a triangulated mesh that the actual island edge
belongs to a different triangle than the current pixel; for example
consider corners of a triangulated axis aligned rectangle face that
have the additional edge: a pixel there will have to be assigned to
one of the triangles, but one of the edges of the original rectangle
can only be accessed through the other triangle.
Thus for robust operation it is necessary to do a recursive search.
The search is limited by requiring that it only goes through edges
that bring it closer to the target point, and also by depth as a
safeguard.
Differential Revision: https://developer.blender.org/D2409
The code requires the pixel on the other side of the seam to be assigned
precisely to the expected triangle. This can cause false negatives around
vertices, where a pixel is likely to touch multiple triangles and thus
cannot be said to unambiguously belong to any one of them, so check
distance to the intended triangle and accept the result if it's close.
1. Forcibly symmetrize the neighbor relations, so that if A is neighbor
of B, B is neighbor of A. The existing code is guaranteed to violate
this if texture resolution is different between the sides of a seam.
2. In texture mode dynamic paint adds a 1 pixel wide border around the
islands. These pixels aren't really part of the dynamic paint domain
and thus by design can't have symmetrical neighbor relations. This
means they can't be treated by effects like normal pixels.
The simplest way to handle it in a consistent way is to exclude
them from effects, but add an additional pass that recomputes them
as average of their non-border neighbors, located on both sides of
the seam.
This splits `interp_weights_face_v3` into `interp_weights_tri_v3` and
`interp_weights_quad_v3`, in order to properly handle three sided polygons
without needing a useless extra index in your weight array. This also
improves clarity and consistency with other math_geom functions, thus
reducing potential future errors.
Reviewed By: mont29
Differential Revision: https://developer.blender.org/D2461
If a very low wetness absolute alpha brush is used with spread and
drying effects enabled, some pixels will rapidly accumulate paint.
This happens because paint drying code applies a minimal wetness
threshold that causes the paint to instantly dry out.
Specifically, every frame the brush adds paint at the specified
absolute alpha and wetness set to the minimal threshold, spread
drops it below threshold, and finally drying moves all paint to
the dry layer. This drastically accelerates the rate of flow of
paint into the affected pixels.
Fortunately, the reason paint spread actually ends up decreasing
wetness turns out to be a simple floating point precision problem,
which can be easily fixed by restructuring the affected expression.
This reverts commit 5aa19be912 and b4a721af69.
Due to postponement of particle system rewrite it was decided to put particle code
back into the 2.8 branch for the time being.
Duplicates can happen at UV seams in case of resolution mismatch
or other complications. It's better not to store them in case it
confuses some math later on.
Reviewers: mont29
Differential Revision: https://developer.blender.org/D2261
1. When adding one pixel border to UV islands prefer grid directions.
This is more logical as it means neighbor pixels will commonly
share a border, opposed to just corners.
2. Don't subtract 0.5 when converting float UVs to int in computing
adjacency across a UV seam. Pixels cover a square with corners
at int positions and adding/subtracting 0.5 is only for dealing
with the center point of a pixel.
3. Use the neighbour_pixel field from the correct pixel, and check
it's not back to the origin point.
4. In the connected UV case, ensure that the returned index actually
refers to a valid active pixel.
This fixes paint spread not traversing some UV seams, while at the
same time spreading to random unrelated points on other seams.
The first problem is primarily fixed by 2, while the second one
is addressed by item 4.
Differential Revision: https://developer.blender.org/D2261
Regression from rBa4a968f, we would adjust current point's wetness without actually protecting it
in new multi-threaded context, leading to concurrent access mess.
Now delay applying wetness reduction to current point to end of function, allows us to avoid having
to lock current point twice together with neighbor one (and reducing spinlock awainting too).
To be backported to 2.78a.
Point cache read code contains checks designed to prevent it reading
stale data when the relevant simulation code should instead compute
the next frame from the previous one. However in some situations like
motion blur subframes the simulation can't possibly do it and just
exits. This causes completely incorrect motion blur at or after the
last cached frame.
To fix, add a parameter that tells the cache code whether it should
apply the checks and exit, or read what it can even if stale (true
means exactly same as old behavior).
Doing this in cache rather than clamping the frame number better in
the caller lets it handle the case of incomplete cache that stops
before the official last frame.
Reviewed By: mont29, lukastoenne
Maniphest Tasks: T49004
Differential Revision: https://developer.blender.org/D2144
