Under the hood the CurveProfile widget (used for bevel custom profiles)
uses a bezier curve, but right now though it only supports two of the
bezier curve handle types, vector and auto. This patch adds support for
free handles and adds all of the logic for editing them.
This is the first step to the ability to import and export curve objects
in the widget.
There's some code cleanup in curveprofile.c. Movement for handles and
control points is abstracted to functions there rather than happening
in interface_handlers.c.
An "Apply Preset" button is also added, which solves a confusing issue
where you apply a preset, then change the number of samples and the
preset doesn't change. The button makes it clear that the preset needs
to be reapplied.
Reviewed By: Severin
Differential Revision: https://developer.blender.org/D6470
Custom profiles in bevel allows the profile curve to be controlled by
manually placed control points. Orientation is regularized along
groups of edges, and the 'pipe case' is updated. This commit includes
many updates to comments and changed variable names as well.
A 'cutoff' vertex mesh method is added to bevel in addition to the
existing grid fill option for replacing vertices.
The UI of the bevel modifier and tool are updated and unified.
Also, a 'CurveProfile' widget is added to BKE for defining the profile
in the interface, which may be useful in other situations.
Many thanks to Howard, my mentor for this GSoC project.
Reviewers: howardt, campbellbarton
Differential Revision: https://developer.blender.org/D5516
