Blender Git Loki

Geometry Nodes: only output new data from Distribute and Instance nodes

This can be recombined with the original data using a
Join node if necessary.

Cleanup: clang tidy

Fix Compilation Error

GCC showed this as a warning, MSVC as an error.

UI: Improvements to interaction with active modifier

This commit includes these improvements to operators and how they
relate to the active modifier:

- Shortcuts performed while there is an active modifier will affect
only that modifier.
- Clicking anywhere on the empty space in a modifier's panel will make
it active.
- Clicking anywhere in the empty properties space will clear the
active.

These changes require some refactoring of object modifier code. First
is splitting up the modifier property invoke callback, which now needs
to be able to get the active modifier separately from the hovered
modifier for the different operators. Second is a change to removing
modifiers, where there is now a separate function to remove a modifier
from an object's list, in order to handle changing the active. Finally
the panel handler neeeds a small tweak so that this "click in panel"
event can be handled afterwards.

Cleanup: Correct node name in definition function

Geometry Nodes: Initial implementation for attribute math node

This provide a simple implementation for basic math operations. Add,
subtract, multiple, and divide are implemented so far. Domain
interpolation is not implemented yet either.

This commit also adds two "Type" options to the node for choosing
explicitly whether to use an attribute or a float value as one of the
inputs. It is not possible to use two floats as inputs, because that
would be a regular math node.

Some cleanup to avoid some code duplication will come in a future
commit.

Geometry Nodes: new Join node

This node creates a new geometry based on two incoming geometries.
In the future the node ui can be extended to support more than two inputs.

The output geometry will have all the attributes of the inputs.
If both inputs have non-matching set of attributes, missing data is either
interpolated, type cast or zeroed.

Ref T82786.

Geometry Nodes: improve geometry component

* It now knows its own component type.
* Add virtual method to check if the component is empty.
* Add virtual methods to find all attribute names.
* Support adding existing components to a geometry set.

Geometry Nodes: disable random attribute node when name is empty

Geometry Nodes: duplicate referenced data layers in attribute api

Cleanup: improve naming convention for geometry node exec functions

Geometry Nodes: Add boilerplate code for attribute math node

This code doesn't actually do anything, but it provides a base for an
implementation and exposes the the necessary interface to the UI.

Cleanup: Doxygen section formatting

Generally doxygen headers are title case and are styled like prose
rather than code.

Merge branch 'master' into geometry-nodes

Merge branch 'master' into geometry-nodes

Geometry Nodes: Switch boolean node inputs

This changes the meaning of the order of the two geometry input sockets
to match the existing boolean modifier. The first socket is now the base
mesh and the second socket is the "cutter" geometry.

Cleanup: Use nullptr instead of NULL in C++ code

Geomtetry Nodes: Set node editor context from the active modifier

Similar to how the node editor context works for materials, this commit
makes the node group displayed in the node editor depend on the active
object and its active modifier. To keep the node group from changing,
just pin the node group in the header.

There are still missing updates when switching the modifier's node group.

Geometry Nodes: Expose the active modifier to the UI

This exposes the operator to set the active modifier as the type icon
in the header of the modifier panels. Tweaks to the widget drawing
code were necessary to use the red alert for non-emboss operator
buttons. Then, the panel for the active modifier gets a border around it
(which currently uses the property search theme color), requiring
an "active property" field in the PanelType struct.

Geometry Nodes: improve boolean node when not both inputs are connected

Previously, it was always outputting an empty geometry in that case.
This was confusing because e.g. the output of a union operation
with a single non-empty mesh is also non-empty.