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
of the nodes, I realized I had strayed from the path of enlightened blending
by causing the math node to create an output the size of the larger of the
two inputs.
It has been corrected create the output the size of the
first image, and in its abscense the second image. In the event of
nether input containing image data the node does not function. I also
added some early out checks at the beginning of the function to speed it
up a tad in these cases and commented the code a bit more.
Basically move stuff out of filesel.c and into language.c and changes
when exactly it does the conversion. It was doing it when not needed for
some machines. It probably still needs work but its slowly getting better.
I also removed some commented out code.
Kent
ID Properties weren't being duplicated (by shift-D or any of the other
duplication functions). So now ID properties are duplicated in the
main copy_libblock function, which (as far as I can check) covers all
ID-contained ID properties.
I also updated the constraint system to copy pyconstraint ID properties
on shift-D.
This would probably be a good thing to add to the stable branch, btw.
Resolved Issues:
* My drawing cleanup commit the other day broke shapekey keyframe selection - was using wrong filter for Action Editor data
* Removed the old hack to limit vertical scrolling so that shapekeys were visible. It wasn't really needed anymore, and was causing problems with HomeKey.
Unresolved Issues:
* Vertical placement of sliders is slightly off
* In a test file I obtained, shapekey sliders don't work immediately after the file is loaded.
This commit should fix some seemingly random crashes broken and I have been experiencing while editing armatures.
A backtrace revealed that autosave was choking on the PoseChannels that didn't have a Bone assigned to them. This was caused by the bone duplication code making a new PoseChannel for a duplicated bone, but that new bone not getting assigned to the PoseChannel yet, as the user was still in EditMode.
"Render to image editor" renders to Buttons Window only if no other suitable
windows are available. Other window types are prioritized before Buttons
Window.
Added new defines for the icons used to show this, on the request of Matt Ebb. For now, the eye icons have simply been duplicated to the new spaces, but 'more descriptive' icons should be made.
Some cleanups of the Action Editor drawing methods. These now make use of the filtering stuff I added for the backend cleanup.
Unfortuantely I still cannot get Blender's ui widgets to really work properly, so that toggle icons can have tooltips. There were some severe scaling issues.
