How can I access cloth properties via python?

Question

I want to manipulate options like Disk Cache with python:

Any Ideas?

Answer 1

Direct Access

You can access all 'cloth properties' of an object by referencing the cloth modifier:

>>> bpy.data.objects['Cube'].modifiers['Cloth'].settings.mass
>>> 0.30000001192092896
>>> bpy.data.objects['Cube'].modifiers['Cloth'].point_cache.frame_start
>>> 0
>>> bpy.data.objects['Cube'].modifiers['Cloth'].point_cache.use_disk_cache
>>> False

To find the desired property you can use python's dir() method, which returns a list of valid attributes for e.g.:

• modifiers['ClothModifierName'].collision_settings
• modifiers['ClothModifierName'].settings
• modifiers['ClothModifierName'].point_cache

which also contain all the relevant attributes.

Click to enlarge

---

Setting Cache attributes like use_disk_cache and frame_start of the active object:

>>> obj = bpy.context.active_object
>>> obj.modifiers['Cloth'].point_cache.use_disk_cache = True
>>> obj.modifiers['Cloth'].point_cache.use_disk_cache
>>> True
>>> obj.modifiers['Cloth'].point_cache.frame_start = 10
>>> obj.modifiers['Cloth'].point_cache.frame_start
>>> 10

To avoid assignment errors you can check the respective 'property type' by using python's built-in type() method:

>>> type(bpy.data.objects['Cube'].modifiers['Cloth'].point_cache.use_disk_cache)
>>> <class 'bool'>
>>> type(bpy.data.objects['Cube'].modifiers['Cloth'].settings.mass)
>>> <class 'float'>

Multiple Objects

In order to set the attributes for multiple 'cloth objects' I'd suggest to check if the respective object has modifiers (also see this answer: Check if active object has a modifier) then iterate through the modifier list and check whether the type is correct:

import bpy
get objects in selection
for obj in bpy.context.selected_objects:
    # check if object has modifiers
    if obj.modifiers:
        print ("has modifiers")
        for modifier in obj.modifiers:
            # if object has cloth modifier
            if modifier.type == "CLOTH":
                # use disk cache attribute
                print (modifier.point_cache.use_disk_cache)
                # set the attribute
                modifier.point_cache.use_disk_cache = True 
                # mass attribute
                print (modifier.settings.mass)
                # set the attribute
                modifier.settings.mass = 1.0

If you need to bake the simulation via python, see this answer: Setting the context for cloth bake