objects – Oded Maoz Erell's CG Log

Python for 3ds max – replace selected objects with a merged object

Posted on April 20, 2019September 28, 2020 by Oded Maoz Erell

Software:
3ds max 2020

The following Python for 3ds max snippet replaces all selected objects with an object merged from an external 3ds max file.

Get this code on gist

Notes:

The ‘model_path’ string variable should be set to the path of the 3ds max file containing the replacement model.
This example takes into account that the merged file contains only a single object, otherwise the first of the merged objects will be used.
The script actually replaces the Object node of the selected objects with the Object node of the merged model (creating instances), assigning them the merged material giving them the merged object’s name appended with numbers.

from MaxPlus import FileManager
from MaxPlus import SelectionManager

model_path = r"D:\Models\Bar_Stool_A.max"

place_holders = []
for o in SelectionManager.Nodes:
     place_holders.append(o)

FileManager.Merge(model_path,True,True)

model = SelectionManager.GetNode(0)

for i in range(len(place_holders)):
     place_holders[i].SetObject(model.GetObject())
     place_holders[i].SetMaterial(model.GetMaterial())
     place_holders[i].SetName(model.Name + "_" + str(i))

model.Delete()

* note that when copying and pasting a script from this example, the indentation may not be pasted correctly.

Python for 3ds max – list scene objects

Posted on March 28, 2019February 11, 2020 by Oded Maoz Erell

Software:
3ds max 2019

Iterating through a list of all of an object’s hierarchy or all of the objects in the scene is a very common requirement for scripted tools and utilities in 3D animation software.
Coming from a MaxScript background, I was used to just have to write the word ‘objects‘ to reference a list of all of the objects in the scene.

Unless I’m missing something obvious,
There isn’t a shortcut like this available in the 3ds max Python API.

In order to list all the objects in the scene you need to use a recursive function that will return a list of all of a node’s children, and children’s children, etc.

In the following example, the function ‘list_children()’ will return a list all of the objects in the supplied node’s hierarchy, and when given the scene’s root node via MaxPlus.Core.GetRootNode() it will return a list of all the objects in the scene.
Wrapping ‘list_children()’ within the ‘scene_objects()’ function, provides a convenient way get a list of all the objects in the scene just by calling ‘scene_objects()’.

def scene_objects():
    def list_children(node):
       list = []
       for c in node.Children:
           list.append(c)
           list = list + list_children(c)
       return list
    return list_children(MaxPlus.Core.GetRootNode())


for o in scene_objects():
    print o.Name

* note that when copying and pasting a script from this example, the indentation may not be pasted correctly.

Python for 3ds max – Create Objects

Posted on February 22, 2019March 28, 2019 by Oded Maoz Erell

Software:
3ds Max 2019

from MaxPlus import ClassIds
from MaxPlus import Point3
import random

# Define Sphere geometry object:
sphere_obj = Factory.CreateGeomObject(ClassIds.Sphere)
sphere_obj.ParameterBlock.Radius.Value = 5
sphere_obj.ParameterBlock.Segs.Value = 64

# Create a list of 10 sphere instanced objects:
spheres = []
for i in range(10):
    spheres.append(Factory.CreateNode(sphere_obj))

# Move spheres to random positions
for s in spheres:
    s.SetLocalPosition(Point3( random.randint(-50,50),
                               random.randint(-50,50),
                               random.randint(-50,50)))
    scale = 5.0 * (random.randint(30,100)/100.0)
    s.SetLocalScale(Point3(scale,scale,scale))

* note that when copying and pasting a script from this example, the indentation may not be pasted correctly.

Blender – Select Pattern

Posted on November 7, 2018 by Oded Maoz Erell

Software:
Blender 2.79

Use the Select Pattern tool to select multiple objects with name similarities.

In the 3D View in Object mode choose Select > Select Pattern…
In the Select Pattern dialog, type a part of a name with an Asterisk to define wild cards.
For example *car* will select all objects who’s names contain the string ‘car’,
And car* will select all objects who’s names begin with the string ‘car’.