obj sequence / mdd ??

Hey All,

I’m looking for a way to bring Blender into our pipeline…

I’ve had a quick look but can’t see anything related to geometry sequences or mdd’s etc

Is there another way to bring in animated geometry from another app?
(namely houdini)

Maybe you did not look hard enough, in blender 2.49 under File, Import there is “Load MDD to Mesh RVK’s”, and i succesfully tested it with XSI some time ago. The exporter counterpart in the menu is File, Export, “Vertex Keyframe Animation”

As for blender 2.5 there only seems to be an exporter and i have not yet tested it.

aah, only been using 2.5 builds… seems i’ll have to wait for this feature to be brought back :frowning: pity… could’ve started using blender in productionn

wow I was looking at the link for blackginger.tv and that’s some really impressive stuff!

it would be great to hear when and if you integrate blender into your pipeline… I’d love to see the results.

i’m trying my hardest :slight_smile:

a mdd modifier would be much appreciated though, hehe :slight_smile:

artz0r, i converted the importer for 2.5:
(copy it to the .blender/scripts/io )

tell me if it works ok :wink:

sweet, thanks Loolarge :slight_smile:

I’ll test it out when i get back to work and can throw some hefty geometry at it!


hey, it works!!! although it only works about 80% correctly, seems some of the point numbers are messed up so it alters the topology… yet it deforms correctly.

here it is in houdini…

and here it is in blender

thankyou so much for your help!!!

by the way, if there are any devs out there listening to this… a mdd modifier would be INSANELY USEFUL in terms of bringing blender to the party with other applications (houdini / xsi etc)

would also bring a lot more interest from studio environments

The mdd importer uses the given vertices in the mesh. How did you import the mesh to blender?

The way i tested was only exporting a mdd from blender 2.49, reopen that file in 2.5 and import mdd.

in case you used the obj importer, try again with these options:
( this is from the 2.4x obj import script)

    if MORPH_TARGET.val: 
        SPLIT_OBJECTS.val = False 
        SPLIT_GROUPS.val = False 
        SPLIT_MATERIALS.val = False 

(So in the 2.5 file browser, deactivate Object, Group and Material)

maybe it helps

yup, that fixes it. thanks :slight_smile:
this is great for now… but it’s actually a nightmare to manage…
for exampled, what if i want to version up the .mdd file?
hence the need for a modifier,

but thanks very much Loolarge!

Yes, you mean a “live” update, without shape keys. As a modifier, that would be great indeed. I am not the greatest coder and also busy with other things, but some day i might tackle this. I’d have to enter the c realm though, i don’t think you can write modifiers in python. However there will be some other possible way to update only on frame change. Just a matter of time i’d say. (maybe allready exists, i don’t know)

edit: to make updating the cache easier, here is how you can get rid of all shape keys at once:

ob = bpy.data.objects['Mesh']
for n in ob.data.shape_keys.keys:

yeah, it’d have to be C. spoke with one of our devs here, he said it should definitely be written in C

okay guys, two more questions in terms of integrating .mdd animation.

firstly i’m trying to do basic hair simming on an animated character. i see Jahka just commited hair collision with other objects… SWEET!!! but, is there a way to comb the hair and then sim it?
it just seems to reset once you run the sim.

second, cloth. i’m bring in the characters clothes, which are also deformed using a mdd to “run” with the character. if i set them to cloth, and the body to a collision object it doesn’t work. the cloth doesn’t see the deforming body as a collider and just falls through it.

any ideas?

oh, and hair dynamics properties can’t be keyed… bug?

using build 27135 linux x64

another issue i just realised. once i’ve simmed hair, how do i get it out of blender? i want to render in houdini, but if i convert the particle modifier it only works for the current frame. and exporting a mdd exports the hair and the emitter geometry?

i think blender will find a nice place in larger studios once these kinds of issues are well thought out. like what if i only want to use blender for CA… or physics etc, keeping a more modular mindset. that way it will sit nicely next to houdini / maya / xsi etc etc

mdd modifier would be very easy to write, perhaps contract a newer developer for this.

Is there any way to make a modifier using python, or does that still have to be coded i n

it would have to be written in C, a good start would be to take a modifier like ‘Cast’ and adjust it to apply from a float array rather then casting from a shape, after that you can add the actual modifier which is a straightforward copy/paste job.

Hi, searched and thought this was the most suitable thread to post in;

im using svn builds of blender 2.5x to make a shot for an advert, working within a team that is mostly using lightwave… we have established a good set of workflows during this project, syntheyes has proved key, tracking and exporting to our three main routes, blender, lightwave and after effects… but we have also animated models in lightwave and imported the motion as mdds into blender - im putting the scene together right now and it is working really well, with a few workarounds…

the lwo importer seems to correct the 90 degrees offset that you come to expect with importers, nice, but the mdd does not, and it also brings the motion in scaled -1 in z… Im fixing this by rotating 90 in x and then -1 in z, applying the changes and then in edit mode selecting all faces and flipping normals… kinda clunky but a testament to blender’s robust nature…

just a post to be informative but also, does anybody know anything about the flipping / rotation?

and just how much time would it take / cost to make a modifier as described above? (might be interesting to get a bounty out if a good offer is made)



I will give it a try during the weekend.