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PickableGroup

Overview

PickableGroup is a Grouping node that can contain most nodes. PickableGroup contains children that are marked as having a given classification of picking types, and can also enable or disable picking of the children.

The PickableGroup node belongs to the Picking component and requires at least level 1, its default container field is children. It is available from X3D version 3.2 or higher.

Hierarchy

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+ X3DNode
  + X3DChildNode
    + X3DGroupingNode
      + PickableGroup (X3DPickableObject)*

* Derived from multiple interfaces.

Fields

SFNode [in, out] metadata NULL [X3DMetadataObject]

Information about this node can be contained in a MetadataBoolean, MetadataDouble, MetadataFloat, MetadataInteger, MetadataString or MetadataSet node.

Hint

SFString [in, out] description “”

Author-provided prose that describes intended purpose of the node.

Hint

  • Many XML tools substitute XML character references for special characters automatically if needed within an attribute value (such as & for & ampersand character, or " for “ quotation-mark character).

SFBool [in, out] pickable TRUE

The pickable field determines whether pick traversal is performed on this node or its children.

Hint

  • pickable only affects children accessed through the transformation hierarchy of the parent.

Warning

  • If one or more of the children of this instance is accessible through another transformation hierarchy through DEF/USE that still has picking enabled, they are still pickable through that path only.

MFString [in, out] objectType “ALL” [“ALL”, “NONE”, “TERRAIN”, …]

The objectType field specifies a set of labels used in the picking process. Each string specified is treated as an independent label that needs to be matched against the same type in one of the pick sensor instances. Example: labeling a PickableGroup with the objectType value “WATER” and then attempting to intersect a pick sensor with objectType value “GROUND” fails since the objectType values do not match. Example: the special value “ALL” means that each node is available for picking regardless of the type specified by the pick sensor. Example: the special value “NONE” effectively disables all picking for this node and is the equivalent of setting the pickable field to false.

Hints

  • Authors may define any value for objectType.
  • MFString arrays can have multiple values, so “separate each individual string” “by using quote marks”.

SFBool [in, out] visible TRUE

Whether or not renderable content within this node is visually displayed.

Hints

  • The visible field has no effect on animation behaviors, event passing or other non-visual characteristics.
  • Content must be visible to be collidable and to be pickable.

SFBool [in, out] bboxDisplay FALSE

Whether to display bounding box for associated geometry, aligned with world coordinates.

Hint

  • The bounding box is displayed regardless of whether contained content is visible.

SFVec3f [ ] bboxSize -1 -1 -1 [0,∞) or −1 −1 −1

Bounding box size is usually omitted, and can easily be calculated automatically by an X3D player at scene-loading time with minimal computational cost. Bounding box size can also be defined as an optional authoring hint that suggests an optimization or constraint.

Hints

SFVec3f [ ] bboxCenter 0 0 0 (-∞,∞)

Bounding box center accompanies bboxSize and provides an optional hint for bounding box position offset from origin of local coordinate system.

Hints

MFNode [in] addChildren

Input field addChildren.

MFNode [in] removeChildren

Input field removeChildren.

MFNode [in, out] children [ ] [X3DChildNode]

Grouping nodes contain an ordered list of children nodes.

Hints

  • Each grouping node defines a coordinate space for its children, relative to the coordinate space of its parent node. Thus transformations accumulate down the scene graph hierarchy.
  • InputOnly MFNode addChildren field can append new X3DChildNode nodes via a ROUTE connection, duplicate input nodes (i.e. matching DEF, USE values) are ignored.
  • InputOnly MFNode removeChildren field can remove nodes from the children list, unrecognized input nodes (i.e. nonmatching DEF, USE values) are ignored.
  • X3D Architecture 10.2.1 Grouping and children node types

Advice

Hints

  • Insert a Shape node before adding geometry or Appearance.
  • Content must be visible to be collidable and to be pickable.

See Also

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