Using python to change the settings of all subdivision surface modifiers

Question

I found this python script to add a subdivision surface modifier to all objects

import bpy

#Iterate over all members inside the Object struct
for ob in bpy.data.objects:
     #Check if object is a Mesh
     if ob.type == 'MESH':
         #Add a SUBSURF Modifier with the name "My SubDiv".
         ob.modifiers.new('My SubDiv', 'SUBSURF')

Is it possible to modify this so that it instead changes the view setting of all subdision surface modifiers?

Answer 1

Rough script for blender 2.79

import bpy

objects = bpy.context.scene.objects
viewlvl = 1

for ob in objects:
    if ob.type == 'MESH':
        objects.active = ob
        for mod in ob.modifiers:
            if mod.type == 'SUBSURF':
                mod.levels = viewlvl

Answer 2

Use the old one if it exists, else create new one.

• Iterated over scene objects rather than all objects in blend.
• If the object already has a modifier named "foo" use it, otherwise create a new one.

test code

import bpy
context = bpy.context

for ob in context.scene.objects:
     if ob.type == 'MESH':
         # get old one or add one
         m = ob.modifiers.get("My SubDiv") or ob.modifiers.new('My SubDiv', 'SUBSURF')
         m.levels = 1
         m.render_levels = 2
         m.quality = 3

oh and in case in testing you have ended up with a cluster of modifiers, here is an example of removing all modifiers with a name starting with "My SubDiv".

for ob in context.scene.objects:
     if ob.type == 'MESH':
         mods = [m for m in ob.modifiers
                 if m.name.startswith("My SubDiv")]
         while mods:
             ob.modifiers.remove(mods.pop())