Add new cavity automasking mode based on local mesh
curvature. Cavity masking is a great way to quickly add
detail in crevices and the like. It's meant to be used
with the Paint brush in color attribute mode. It does
work with other brushes but the results can be unpredictable.
{F13131497}
The old "dirty mask" operator has been replace with a new
"mask from cavity" operator that shares the same code with
cavity automasking.
Differences from the sculpt-dev implementation:
* It uses the word "cavity." When I first implemented
this I wasn't aware
this feature existed in other software (and other
paint modes in Blender),
and for reasons that escape me today I initially
decided to call it a concave or
concavity mask.
* The cavity factor works a bit differently. It's
no longer non-linear and functions as a simple
scale around 0.5f.
* Supports custom curves.
* Supports blurring.
Reviewed By: Julian Kaspar, Jeroen Bakker and Campbell Barton
Differential Revision: https://developer.blender.org/D15122
Ref D15122
This adds support for showing geometry passed to the Viewer in the 3d
viewport (instead of just in the spreadsheet). The "viewer geometry"
bypasses the group output. So it is not necessary to change the final
output of the node group to be able to see the intermediate geometry.
**Activation and deactivation of a viewer node**
* A viewer node is activated by clicking on it.
* Ctrl+shift+click on any node/socket connects it to the viewer and
makes it active.
* Ctrl+shift+click in empty space deactivates the active viewer.
* When the active viewer is not visible anymore (e.g. another object
is selected, or the current node group is exit), it is deactivated.
* Clicking on the icon in the header of the Viewer node toggles whether
its active or not.
**Pinning**
* The spreadsheet still allows pinning the active viewer as before.
When pinned, the spreadsheet still references the viewer node even
when it becomes inactive.
* The viewport does not support pinning at the moment. It always shows
the active viewer.
**Attribute**
* When a field is linked to the second input of the viewer node it is
displayed as an overlay in the viewport.
* When possible the correct domain for the attribute is determined
automatically. This does not work in all cases. It falls back to the
face corner domain on meshes and the point domain on curves. When
necessary, the domain can be picked manually.
* The spreadsheet now only shows the "Viewer" column for the domain
that is selected in the Viewer node.
* Instance attributes are visualized as a constant color per instance.
**Viewport Options**
* The attribute overlay opacity can be controlled with the "Viewer Node"
setting in the overlays popover.
* A viewport can be configured not to show intermediate viewer-geometry
by disabling the "Viewer Node" option in the "View" menu.
**Implementation Details**
* The "spreadsheet context path" was generalized to a "viewer path" that
is used in more places now.
* The viewer node itself determines the attribute domain, evaluates the
field and stores the result in a `.viewer` attribute.
* A new "viewer attribute' overlay displays the data from the `.viewer`
attribute.
* The ground truth for the active viewer node is stored in the workspace
now. Node editors, spreadsheets and viewports retrieve the active
viewer from there unless they are pinned.
* The depsgraph object iterator has a new "viewer path" setting. When set,
the viewed geometry of the corresponding object is part of the iterator
instead of the final evaluated geometry.
* To support the instance attribute overlay `DupliObject` was extended
to contain the information necessary for drawing the overlay.
* The ctrl+shift+click operator has been refactored so that it can make
existing links to viewers active again.
* The auto-domain-detection in the Viewer node works by checking the
"preferred domain" for every field input. If there is not exactly one
preferred domain, the fallback is used.
Known limitations:
* Loose edges of meshes don't have the attribute overlay. This could be
added separately if necessary.
* Some attributes are hard to visualize as a color directly. For example,
the values might have to be normalized or some should be drawn as arrays.
For now, we encourage users to build node groups that generate appropriate
viewer-geometry. We might include some of that functionality in future versions.
Support for displaying attribute values as text in the viewport is planned as well.
* There seems to be an issue with the attribute overlay for pointclouds on
nvidia gpus, to be investigated.
Differential Revision: https://developer.blender.org/D15954
This patch replaces the existing transfer attribute node with three
nodes, "Sample Nearest Surface", "Sample Index", and "Sample Nearest".
This follows the design in T100010, allowing for new nodes like UV
sampling in the future. There is versioning so the new nodes replace
the old ones and are relinked as necessary.
The "Sample Nearest Surface" node is meant for the more complex
sampling algorithms that only work on meshes and interpolate
values inside of faces.
The new "Sample Index" just retrieves attributes from a geometry at
specific indices. It doesn't have implicit behavior like the old
transfer mode, which should make it more predictable. In order to not
change the behavior from existing files, the node has a has a "Clamp",
which is off by default for consistency with the "Field at Index" node.
The "Sample Nearest" node returns the index of the nearest element
on a geometry. It can be combined with the "Sample Index" node for
the same functionality as the old transfer node. This node can support
curves in the future.
Backwards compatibility is handled by versioning, but old versions can
not understand these nodes. The warning from 680fa8a523 should make
this explicit in 3.3 and earlier.
Differential Revision: https://developer.blender.org/D15909
For example, allows a custom UV grid size of 4 x 12.
TODO: Fix snapping with custom UV grid sizes.
Manifest Tasks: T78391
Differential Revision: https://developer.blender.org/D16000
