Motivation

You can group shapes to compose complex shapes

X3D has several grouping nodes, including:

Syntax: Group

The Group node creates a basic group.

• Every child node in the group is displayed.

Syntax: Switch

The Switch group node creates a switched group

• Only one child node in the group is displayed
• You select which child
  • Children implicitly numbered from 0
  • A -1 selects no children

Syntax: Transform

The Transform group node creates a group with its own coordinate system.

• Every child node in the group is displayed.

Syntax: Billboard

The Billboard group node creates a group with a special coordinate system.

• Every child node in the group is displayed.
• The coordinate system is turned to face viewer.

Billboard rotation axes

• A rotation axis defines a pole to rotate round
• Similar to a Transform node's rotation field, but no angle (auto computed)
• A standard rotation axis limits rotation to spin about that axis
• A zero rotation axis enables rotation around any axis

A sample billboard group

Syntax: Anchor

An Anchor node creates a group that acts as a clickable anchor

• Every child node in the group is displayed
• Clicking any child follows a URL
• A description names the anchor

Syntax: Inline

An Inline node creates a special group from another X3D file's contents

• Children read from file selected by a URL
• Every child node in group is displayed

Summary

• The Group node creates a basic group
• The Switch node creates a group with 1 choice used
• The Transform node creates a group with a new coordinate system
• The Billboard node creates a group with a coordinate system that rotates to face the viewer
• The Anchor node creates a clickable group
  • Clicking any child in the group loads a URL
• The Inline node creates a special group loaded from another X3D file