This commit adds a new constraint to Blender: the Transformation Constraint. This constraint gives you more freedom to choose how transforms are copied from one object/bone to another object/bone.
You can assign the Loc/Rot/Scale channels of a source to the Loc/Rot/Scale channels of a destination, specifying the range of motion (per axis) from the source to consider, and the range of motion (per axis) that will be applied to the destination. Also, for each destination axis, you can choose which of the source axes to copy from.
A similar constraint was coded by Jason Blary (snark), as Patch #4991. This constraint is basically rewritten from scratch, although there are some elements of the original patch which may be borrowed in future.
Various notes:
* PyAPI access has been coded.
* Space conversion is also enabled for this constraint.
* Also the useless get_constraint_col function has been removed
* Doing a rotation copy with a ratio that is not 1:1 doesn't always work correctly yet (like for the Copy Rotation constraint).
After just over a week of coding, I've finished doing a major refactor/cleanup of the constraints code. In the process, quite a few old kludges and ugly hacks have been removed. Also, some new features which will greatly benefit riggers have been implemented.
=== What's New ===
* The long-awaited ``ChildOf Constraint'':
This allows you to animate parent influences, and choose which transformation channels the parent affects the child on (i.e. no translation/rotation/scaling). It should be noted that disabling some combinations may not totally work as expected. Also, the 'Set Inverse' and 'Clear Inverse' buttons at the bottom of this constraint's panel set/clear the inverse correction for the parent's effects. Use these to make the owner not stick/be glued to the parent.
* Constraint/Target Evaluation Spaces:
In some constraints, there are now 1-2 combo boxes at the bottom of their panel, which allows you to pick which `co-ordinate space' they are evaluated in. This is much more flexible than the old 'local' options for bones only were.
* Action Constraint - Loc/Rot/Size Inputs
The Action Constraint can finally use the target's location/rotation/scaling transforms as input, to control the owner of the constraint. This should work much more reliably than it used to. The target evaluation should now also be more accurate due to the new space conversion stuff.
* Transform - No longer in Crazy Space (TM)
Transforming objects/bones with constraints applied should no longer occur in Crazy Space. They are now correctly inverse-corrected. This also applies to old-style object tracking.
=== General Code Changes ===
* solve_constraints is now in constraints.c. I've removed the old `blend consecutive constraints of same type' junk, which made the code more complex than it needed to be.
* evaluate_constraint is now only passed the constraint, and two matrices. A few unused variables have been removed from here.
* A tempolary struct, bConstraintOb, is now passed to solve_constraints instead of relying on an ugly, static workobject in some cases. This works much better.
* Made the formatting of constraint code consistent
* There's a version patch for older files so that constraint settings are correctly converted to the new system. This is currently done for MajorVersion <= 244, and SubVersion < 3. I've bumped up the subversion to 3 for this purpose. However, with the imminent 2.45 release, this may need to be adjusted accordingly.
* LocEulSizeToMat4 and LocQuatSizeToMat4 now work in the order Size, Rot, Location. I've also added a few other math functions.
* Mat4BlendMat4 is now in arithb. I've modified it's method slightly, to use other arithb functions, instead of its crazy blending scheme.
* Moved some of the RigidBodyJoint constraint's code out of blenkernel, and into src. It shouldn't be setting its target in its data initialisation function based + accessing scene stuff where it was doing so.
=== Future Work ===
* Geometry to act as targets for constraints. A space has been reserved for this already.
* Tidy up UI buttons of constraints
The BPy Access to PyConstraints. I have not implemented the setter for the PyC-ID-Properties access as I'm not too sure how this should be done.
Also fixed a few typos in the py-docs for the Limit Scale constraint.
At last! The ability to code constraints in Python. This opens up many interesting rigging possibilities, as well as making prototyping constraints easier.
* A PyConstraint script must begin with the line
#BPYCONSTRAINT
* It must also define a doConstraint function, which performs the core actions of the constraint.
* PyConstraints use IDProperties to store custom properties for each PyConstraint instance. The scripter can choose which of these ID-Properties to expose to a user to control the behaviour of the constraint. This must be done using the Draw.PupBlock method.
Credits to Joe Eager (joeedh) for coding the original patch on which this is based. I've made heavy revisions to large parts of the patch.
For more detailed information, and some demo scripts, see the following page:
http://aligorith.googlepages.com/pyconstraints2
Checked every instance of testbase to see this dosnt break anything, also changed TESTBASE and TESTBASELIB, both were used incorrectly in places.
added error_libdata() for library error messages that are everywhere.
added object_data_is_libdata to test if the object and its data's are from a library.
fixed 2 crashs in adding Curve points to a library object (remember to check, verify_ipocurve returns NULL!)
made duplicating and making dupli's real for lib objects possible, disabled joining into lib armatures and meshes.
Adding Python counterparts to the Invert params for Copy Rot and Copy Loc.
I had to align the constants being used, so if you had files using those options (introduced after 2.43), you'll have to modify the INVERT settings for ROTLIKE constraints (didn't feel like making a minor version bump for this, if people thing otherwise, please say so).
Based on a patch by Juho Vepsäläinen (bebraw)
making it much more useful. Requested and taunted for frequently by
Plumiferos folks. Click on "Use Rot" to take target object rotations
into account.
Good for using rotated empties, etc., as a sloped floor.
Moved .up() and .down() methods from Constraint API to Constraint sequence
API (also renamed them to moveUp() and moveDown() ). Again, methods which
modify the "parent" structure didn't seem consistent.
* use CONSTRAINT_LOCAL instead of SELECT in "Copy Rotate" constraint
* remove "LOCAL" key for now from "Copy Size" constraint; not supported
right now in Blender UI
Added NULL constraint (and fixed bug that didn't allow appending FLOOR
constraint), and added support for Constraint.Settings.LOCAL key support in
COPYLOC, COPYROT and COPYSIZE constraints when target object is an armature.
New Constraint API. Constraints are accessible through a "constraints"
attribute in poses and objects. Would be REALLY NICE for armature users to
pound on this code.
