The roll value may not be as expected when a matrix is not orthogonal
or has a negative determinant.
This can lead to confusion as seen in T82930.
Therefore, make it clear that this is a limitation and that a value for
the roll is somewhat indeterminable in these cases.
This fixes T82930
As an inherent property of matrix-based transformation math, non-
uniform scaling of a parent bone induces shear into the transform
matrix of any rotated child. Such matrices cannot be cleanly
decomposed into a combination of location/rotation/scale, which
causes issues for rigging and animation tools.
Blender bones have options to exclude rotation and/or scale from the
inherited transformation, but don't have any support for removing the
often undesired shear component. That goal requires replacing simple
parenting with a combination of multiple bones and constraints. The
same is true about the goal of inheriting some scale, but completely
avoiding shear.
This patch replaces the old Inherit Scale checkbox with a enum that
supports multiple options:
* Full: inherit all effects of scale, like with enabled Inherit Scale.
* Fix Shear: removes shear from the final inherited transformation.
The cleanup math is specifically designed to preserve the main
axis of the bone, its length and total volume, and minimally
affect roll on average. It however will not prevent reappearance
of shear due to local rotation of the child or its children.
* Average: inherit uniform scale that represents the parent volume.
This is the simplest foolproof solution that will inherit some
scale without ever causing shear.
* None: completely remove scale and shear.
* None (Legacy): old disabled Inherit Scale checkbox.
This mode does not handle parent shear in any way, so the child
is likely to end up having both scale and shear. It is retained
for backward compatibility.
Since many rigging-related addons access the use_inherit_scale
property from Python, it is retained as a backward compatibility
stub that provides the old functionality.
As a side effect of reworking the code, this also fixes a matrix
multiplication order bug in the Inherit Rotation code, which caused
the parent local scale to be applied in world space. In rigger
opinion this option is useless in production rigs, so this fix
should not be a problem.
Reviewers: brecht
Differential Revision: https://developer.blender.org/D5588
BF-admins agree to remove header information that isn't useful,
to reduce noise.
- BEGIN/END license blocks
Developers should add non license comments as separate comment blocks.
No need for separator text.
- Contributors
This is often invalid, outdated or misleading
especially when splitting files.
It's more useful to git-blame to find out who has developed the code.
See P901 for script to perform these edits.
Applying the effect of bone parent is much more complicated than
simple matrix multiplication because of the various flags like
Inherit Scale. Thus it is reasonable to provide access to this
math from Python for complicated rest pose related manipulations.
The simple case of this is handled by Object.convert_space, so
the new method is only needed for complex tasks.
Differential Revision: https://developer.blender.org/D4053
B-Bone shape is a non-trivial computation, so access to
the results would be useful for Python scripts working with
B-Bones, e.g. rig generation.
This exposes both final segment matrices, and the tangent
vectors computed from the custom handle bones.
Since the handle tangents use the axis+roll orientation math
of edit bones, add matrix conversion static methods to Bone.
Reviewers: campbellbarton
Differential Revision: https://developer.blender.org/D3983
- Wasn't clear which functions handle edit-bones.
- Mixed both ebone and edit_bone in names.
- Didn't use ED_armature_* prefix for public API.
See P655 to apply to branches.
This gives us 9 flags available again for properties (we had none anymore),
and also makes things slightly cleaner.
To simplify (and make more clear the differences between mere properties
and function parameters), also added RNA_def_parameter_flags function (and
its clear counterpart), to be used instead of RNA_def_property_flag for
function parameters.
This patch is also a big cleanup (some RNA function definitions were
still using 'prop' PropertyRNA pointer, etc.).
And yes, am aware this will be annoying for all branches, but we really need
to get new flags available for properties (will need at least one for override, etc.).
Reviewers: sergey, Severin
Subscribers: dfelinto, brecht
Differential Revision: https://developer.blender.org/D2400
Note about long lines: I did not touch to two pieces of code (because I don’t see any way to keep a nicely formated, compact code, with shorter lines):
* The node types definitions into rna_nodetree_types.h
* The vgroup name functions into rna_particle.c
from Josh Wedlake (joshwedlake), who provided a reference script used to apply changes in ED_rollBoneToVector().
- Obvious bug fixed where Z-Up didnt work right.
- More align axis options to Recalculate Roll operator: X/Y/Z/View Axis & Negate.
- Axis Only option, ignore the axis direction, use shortest rotation to align bones.
ED_rollBoneToVector() changes:
- would give bad roll when the axis wasn't normalized or perpendicular to the bone.
some callers accounted for this but not all.
- option to align to the axis but not the direction.
from Dan Eicher (dna)
Basically just wraps distfactor_to_bone() and passes the correct head/tail depending on which bone type it's called
from.
note:
renamed envelope() --> evaluate_envelope()
* option to roll the delta of the arm rig.
* fix to copy metarig type
* renamed EditBone.align() --> EditBone.align_roll()
* Added EditBone.align_orientation(other)
* Added bone.vector: same as (bone.tail - bone.head)
