can shape keys work with diferant vertex counts?

hey everyone
just a quick question. i have a character who can morph between human and dragon, and i want to animate the morph but realized the human model and the dragon model have two diferant amounts of vertcies, and i’m told that you need the same number for it to work. is there any way around this?

i don’t like to say that i’m certain of anything, but i’m pretty certain what you were told is right. :frowning: shape keys store vertex positions relative to the basis shape, and the results get pretty catastrophic when the number of vertex positions stored in a shape key and that of the basis shape are different. that’s why it’s not advisable to extrude or delete anything from your model after you’ve started creating shape keys.

if i’m wrong, though, i’d love to know!

so is there anything else i can do? surely shape keys aren’t the only way of doing it…
if not i have a sort of back up plan but it’s not as good as haveing the morph there.

i’m really curious, what is your backup plan? i can only think of doing something like this in post, rendering a separate pass of the character and distorting it in video editing software

what i plan to do is use a sphere and make it glow. i’ll animate it getting brighter and brighter then, once got to the point you can’t see what’s inside it, move the character out of ther scene, probably under the scene floor or something and slide the other charater back up, into the position where the first stood, then animate the glow to get dimmer untill it’s no existalant. if i can’t put the characters under the scene, i’ll make one so small, it’s be nearly imposible to see, and have it on a seperate layer so i don’t lose it, and while the sphere is glowing, make that one larger and shrink the other one.

Creating shape morphs using the shrinkwrap mod. Attached is a file with a default cube wrapped onto the monkey. Uses vertex groups for top,left,right etc for faces of the cube. They are then projected onto the shape or the axis=0 plane…

Point of info, not only do shape keys require the same vertex count, but also the same vertex order (an internal property of the mesh), else you can get extremely odd and generally useless results. batFINGER’s Shrinkwrap trick is a good start but you have to be careful when setting it up that the portions of the stage 1 mesh wrap to the proper portions of the stage 2 mesh, for example, human’s head to dragon’s head. Otherwise the morph can end up looking very weird.

One method might be to create a special “morph mesh” of fairly high density (lots of vertices) that would be used only for the shape key progression. Using the mesh-replacement methods you mention, dragongirl, you could swap in the morph mesh, let it change, then swap in the appropriate “end-state” mesh, either human or dragon. The start and end poses of all 3 models would match so there would be no noticeable “twitch” at the transition. Some post work could sweeten things up with cross-fades, effects, etc.

I used something like this in Kata at around 2:51:00 to have one of the shadow dancer creatures change from its “normal” form to one that acts like a sheet of very stretchy fabric. The stage one form used cloth, shape keys and armature animation. A duplicate was created with exactly the same shape at the point where the dancer grabs it, then animated as pure cloth for the next action. This was converted to shape keys and tweaked, then both sequences (pre- and post-grab actions) were rendered with a few overlapping frames that were blended in post.

wow thanks!

OK, so I’m looking to take a simple cube, and extrude it into a basic three-branch tree. I guess this is the same kind of deal–the extrusions of the cube to form the tree can’t be tracked by the Shape Keys, so I’m SOL?