# Export multiple .MDD at once?

I have 97 MDD files created from different meshes (armature deformed, cloth deformed etc). Is there a way to select multiple meshes and export them as individual MDD files?

I have seen that there's another post which provides an add-on to export selected objects to FBX, but unfortunately I do not have the skills adapting it to work for MDD files: Exporting multiple meshes individually at once

My progress so far: I've found someone trying to export multiple MDD at once on another forum, and it seems that there's a Python command line to export a MDD: bpy.ops.export_shape.mdd(fps=24, frame_start=1, frame_end=250). Also, there's a python template for Batch exporting:

import bpy
import os

# export to blend file location
basedir = os.path.dirname(bpy.data.filepath)

if not basedir:
raise Exception("Blend file is not saved")

view_layer = bpy.context.view_layer

obj_active = view_layer.objects.active
selection = bpy.context.selected_objects

bpy.ops.object.select_all(action='DESELECT')

for obj in selection:

obj.select_set(True)

# some exporters only use the active object
view_layer.objects.active = obj

name = bpy.path.clean_name(obj.name)
fn = os.path.join(basedir, name)

bpy.ops.export_scene.fbx(filepath=fn + ".fbx", use_selection=True)

# Can be used for multiple formats
# bpy.ops.export_scene.x3d(filepath=fn + ".x3d", use_selection=True)

obj.select_set(False)

print("written:", fn)

view_layer.objects.active = obj_active

for obj in selection:
obj.select_set(True)


How can I export multiple .MDD files ?

• Is there any mdd exporter already? If so you just have to replace export_scene.fbx() operator and all corresponding properties/arguments. Dec 20, 2020 at 18:06
• @brockmann (I deleted my answer and edited my original post). What do you mean ? Yes, there's a .mdd exporter built in Blender but no option for Batch exporting is displayed. As I said, I don't understand how Python works, and replacing the ".fbx" by ".mdd" gives me an error. Also, I don't know any Python functions, neither specific .mdd arguments. So I need help here, I guess mixing the Batch Export template with the specific .mdd exporting function will do the trick ?
– Pdhm
Dec 20, 2020 at 18:22
• Modified the code of the linked answer: pasteall.org/UhqR Make sure the other mdd exporter is enabled, run the code in the text editor, please test and report back. Dec 20, 2020 at 18:41
• Hey, thanks for your help. Yes, the MDD exporter add-on is enabled. Copy/Pasted the code in the text editor, saved it and hitted run : bpy.ops.text.run_script() in the system console aand.. that's it. Nothing else happens, no .mdd output in the directory, no loading time after hitting the Play button :/
– Pdhm
Dec 21, 2020 at 9:49
• Go to File > Export > Batch export mdd to execute the process (as usual). Dec 21, 2020 at 9:50

Addon based on this answer, adapted to export all objects in selection to single .mdd files. Make sure 'NewTekk MDD format' add-on is enabled and install the add-on as usual:

### batch_mdd_export.py

# ##### BEGIN GPL LICENSE BLOCK #####
#
#  This program is free software; you can redistribute it and/or
#  modify it under the terms of the GNU General Public License
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program; if not, write to the Free Software Foundation,
#  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# ##### END GPL LICENSE BLOCK #####
# <pep8 compliant>
​
bl_info = {
"name": "Batch export MDD files",
"author": "brockmann",
"version": (0, 1, 0),
"blender": (2, 80, 0),
"location": "File > Import-Export",
"description": "Batch Export Objects in Selection to MDD",
"warning": "",
"wiki_url": "",
"tracker_url": "",
"category": "Import-Export"}
​
​
import bpy
import os
​
from bpy_extras.io_utils import ExportHelper
​
from bpy.props import (BoolProperty,
FloatProperty,
IntProperty,
StringProperty,
EnumProperty,
CollectionProperty
)
​
​
class Batch_MDD_Export(bpy.types.Operator, ExportHelper):
"""Batch export objects to fbx files"""
bl_idname = "export_scene.batch_mdd"
bl_label = "Batch export MDD"
bl_options = {'PRESET', 'UNDO'}
​
# ExportHelper mixin class uses this
filename_ext = ".mdd"
​
filter_glob : StringProperty(
default="*.mdd",
options={'HIDDEN'},
)
​
# List of operator properties, the attributes will be assigned
# to the class instance from the operator setting before calling.

# Context group
use_selection_setting: BoolProperty(
name="Selection Only",
description="Export selected objects only",
default=True,
)
​
use_rest_frame: BoolProperty(
name="Use Rest Frame",
description="ToDo",
default=False,
)

frames_per_second: FloatProperty(
name="FPS",
description="ToDo",
min=1, max=60,
default=25,
)
​
frame_start: IntProperty(
name="Frame Start",
description="ToDo",
default=1,
)

frame_end: IntProperty(
name="Frame End",
description="ToDo",
default=250,
)

def execute(self, context):
​
# get the folder
folder_path = os.path.dirname(self.filepath)
​
# get objects selected in the viewport
viewport_selection = context.selected_objects
​
# get export objects
obj_export_list = viewport_selection
if self.use_selection_setting == False:
obj_export_list = [i for i in context.scene.objects]
​
# deselect all objects
bpy.ops.object.select_all(action='DESELECT')
​
for item in obj_export_list:
item.select_set(True)
if item.type == 'MESH':
context.view_layer.objects.active = item # Set active object
file_path = os.path.join(folder_path, "{}.mdd".format(item.name))
​
# MDD settings
bpy.ops.export_shape.mdd(
filepath=file_path,
fps=self.frames_per_second,
frame_start=self.frame_start,
frame_end=self.frame_end
)
​
item.select_set(False)
​
# restore viewport selection
for ob in viewport_selection:
ob.select_set(True)
​
return {'FINISHED'}
​
​
# Only needed if you want to add into a dynamic menu
self.layout.operator(Batch_MDD_Export.bl_idname, text="MDD Batch Export (.mdd)")
​
​
def register():
bpy.utils.register_class(Batch_MDD_Export)
​
​
def unregister():
bpy.utils.unregister_class(Batch_MDD_Export)
​
​
if __name__ == "__main__":
register()
​
# test call
#bpy.ops.export_scene.batch_mdd('INVOKE_DEFAULT')


I added all possible arguments of the 'lightwave point cache' operator export_shape.mdd(), see line 117. You can change them or add new properties to the operator, wasn't sure.

• Hey, just giving you a feedback : it seems that this script exports the same mesh (the active one, so the first one) over and over. In my case I have the same .mdd for 97 times. I understand that the "for" is used to do an incremental .mdd export but I was not able to find how to correct it. Could you give it a try ? Sorry to ask for your help again :/
– Pdhm
Dec 22, 2020 at 12:52
• Oh and I forgot to mention that the names are correctly set !
– Pdhm
Dec 22, 2020 at 13:17
• Not sure I can properly test the output since I don't have access to Lightwave. Might be necessary to set the current object to the active one, updated the code: pasteall.org/2ukq Does that work? @Pdhm Dec 22, 2020 at 13:28
• First, thanks for helping me in such an efficient way, I really appreciate it. Secondly : YES it worked ! :) I tested it on three .mdd exports for a limited amount of frames but it worked. I'll give a try over a lot more now but I need an hour of calculation. Will update you in a couple of hours. Again, thank you very much !
– Pdhm
Dec 22, 2020 at 13:47