This fixes a precision issue in multi-paint so that near zero values do not cause flickering as you paint.

It also changes multi-paint's "zero weight color" to black again--it was unintentionally changed to red some time late last year when an aspect of the colors were changed.

The locking + multi-paint section of code needed correction and simplification:
The ratios were only being maintained between the altered weights when they were redistributed,
and the resulting weights did not fully respect the locks--now they do.

While reviewing this part of the code for a Blender Proceedings article, I noticed that the lock enforcer was taking several improper steps to redistribute evenly with multi-paint.

Beforehand, a few problems were in view: some of the indexing was changed towards the end to use the more efficient stack structure, but needed to use the correct def group indices.

Also, the designated selected group would use its own value to acquire the standard to base change distributed to the others.

Lastly, the total_change was used rather than -left_overs in the formula to compute the new designated weight within the means of the locks' allowed changes.


Now, while maintaining the ratios of the selection, it correctly returns left over change that could not be redistributed to the unlocked groups.

Merging radish branch into trunk.
http://wiki.blender.org/index.php?title=User:Jason_hays22/GSoC-2011

Merged 40338-40364

vgroup_validmap needed to be assigned when locks were active.

Split do_weight_paint_vertex() to isolate the simple case.

Added a tool-tip to the "fix deforms" op.

Removed code markers:
"Radish"

Changed the branch code markers to say "Radish" in response to a review.
They weren't & aren't meant to show ownership, they just help me navigate my related code.

I made multitude of fixes based on the comments provided online:

Removed the drawSelectedVerts and added drawSelectedVertices, which uses dm->foreachMappedVert.

In calc_weightpaint_vert_color():
Made the weight paint color black and return instead of input=-1

Made the pose bone selection normal when multi-paint is inactive.

Name fix for functions using mv instead of mvert.

Used vector functions provided by the math lib.

Changed some MEM_callocN references to be stacks.

Changed dm_deform_clear to use ob->derivedDeform primarily

Made the variable "float **changes" into "float (*changes)[2]"

Used CTX_data_active_object() in place of CTX_data_pointer_get_type()

Added the invert selection hotkey "Ctrl+I" to weight paint's vertex mask.

Re-added the interface template for vertex groups' checkboxes (they were cut out in a merge conflict)