Consider a situation where you need to model hundreds of chairs for a cinema theatre. The chairs all look the same, only their position and orientation vary.

Instances allow you to manage this kind of situations efficiently. An instanced object duplicates its source object. When the source object is modified, all instances referring to it will change accordingly. Instances can be transformed or deformed using any available modify function including single point editing. Instances can be instanced, instances of instances can be instanced, etc.

For example:

1. Model a chair of a movie theatre.

A sample chair

2. Make sure that the chair is selected. Then select the pull-down menu Edit/Instance.

Modifying Instance Objects

You can modify an instance object using all common tools, such as delete, duplicate, move, rotate and scale:

3. Select the instance of the chair and activate the Move tool.

4. Move the instance to the right side of the original chair.

We can use the macro system to achieve more instances quickly:

5. Select Macros/Record from the pull-down menu.

6. Select the instance object. Select Edit/Duplicate. Then move the duplicated instance to the right.

7. Select Macros/Record again from the pull-down menu to switch macro recording off. Go to the Macros tab of the select window. Enter a suitable value to the Repetitions field and click Apply.

A row of chairs

Modifying the Source Object of Instances

Let's improve the chairs. Because of instancing, only one chair needs improvements:

8. Add a neck support to the sub hierarchy of the original chair.

9. Select all sub objects of the original chair and rotate them.

All instances change to reflect these modifications.

More comfortable chairs

Properties of instances