Maya Blendshape system


#1

Maya 2018.2’s Blendshape system is scaring us… its doing some sort of mystical sorcery in the background and I would like to get some
clarification on it before continuing.

So, by my knowledge/experience (14 years) when creating blendshapes, maya is
basically storing the delta changes of a vertex, and its vertex ID, and
then blending between its base and the target delta, so, in saying that,
if one were to change the vert count…in ANY way, (adding edge,
deleting extruding…anything really) in tern changing the vertex counts
and IDs, this should break all your blendshapes.

with the new shape editor… this does not seem to be the case anymore… what gives O_O
I have created a head, added targets, made a target shapes and then gone
back into my mesh and deleted a mouthbag, made extrusions and cut in a
new edge, deleted non-deformer history and all my blends are still fine.
I’m scared because although all this is really cool and makes life
better… im dreading that it will eventually break somewhere down the
line.

Is maya creating the targets off of the base blend shapes as instance meshes in the background?
Ideally I would like one of the Autodesk devs to answer this… otherwise, does someone have a email or number of a autodesk dev


#2

Been in a middle of a project, so I had no chance to update and try out the blendshape system.
But regarding your concern, how about posting it in the autodesk forum?
They usually give a comprehensive answer.


#3

I have posted it in the official forum and still no proper response on what its doing in the background.
https://forums.autodesk.com/t5/maya-forum/maya-blendshape-system/m-p/8055255/highlight/false
under further tests and investigation… It seems to be a case of maya uses the original shape’s ShapeOrig node and creates all the transforms on top of it (if you look in the node editor) but it still does not explain to me that if I go in and extrude on the original object how nothing breaks.


#4

if autodesk isnt responding maybe contact Chad…
this tech is based on the camD tools…
http://www.chadvernon.com/blog/creature-art-and-mechanics/