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The SoVRMLCylinderSensor maps pointing device (e.g. mouse or wand) motion into a rotation on an invisible cylinder that is aligned with the Y axis of its local space.

<font color="#0000FF">NOTE:</font> This class does not exist in Open Inventor 10.0 and later.

VRML97 SPECIFICATION

This section describes the expected behavior of the node in a conforming VRML97 browser application. In some cases, the application is responsible for implementing portions of the expected behavior. Open Inventor viewer classes and IVF classes implement some of the application behaviors.

This section may reference portions of the VRML97 specification that are not present in this help file. The complete VRML97 spec is available at http://www.web3d.org.

The SoVRMLCylinderSensor maps pointing device (e.g. mouse or wand) motion into a rotation on an invisible cylinder that is aligned with the Y axis of its local space.

The enabled exposed field enables and disables the SoVRMLCylinderSensor - if true, the sensor reacts appropriately to user events, if false, the sensor does not track user input or send output events. If enabled receives a false event and isActive is true, the sensor becomes disabled and deactivated, and outputs an isActive false event. If enabled receives a true event the sensor is enabled and ready for user activation.

The SoVRMLCylinderSensor generates events if the pointing device is activated while over any descendant geometry nodes of its parent group and then moved while activated. Typically, the pointing device is a 2D device such as a mouse. The pointing device is considered to be moving within a plane at a fixed distance from the viewer and perpendicular to the line of sight; this establishes a set of 3D coordinates for the pointer. If a 3D pointer is in use, then the sensor generates events only when the pointer is within the user's field of view. In either case, the pointing device is considered to "pass over" geometry when that geometry is intersected by a line extending from the viewer and passing through the pointer's 3D coordinates. If multiple sensors' geometries intersect this line (hereafter called the bearing), only the nearest will be eligible to generate events.

Upon activation of the pointing device (e.g. mouse button down) over the sensor's geometry, an isActive true event is sent. The angle between the bearing vector and the local Y axis of the SoVRMLCylinderSensor determines whether the sides of the invisible cylinder or the caps (disks) are used for manipulation. If the angle is less than the diskAngle, then the geometry is treated as an infinitely large disk and dragging motion is mapped into a rotation around the local Y axis of the sensor's coordinate system. The feel of the rotation is as if you were rotating a dial or crank. Using the right-hand rule, the X axis of the sensor's local coordinate system, (defined by parents), represents the zero rotation value around the sensor's local Y axis. For each subsequent position of the bearing, a rotation_changed event is output which corresponds to the angle between the local X axis and the vector defined by the intersection point and the nearest point on the local Y axis, plus the offset value. trackPoint_changed events reflect the unclamped drag position on the surface of this disk. When the pointing device is deactivated and autoOffset is true, offset is set to the last rotation angle and an offset_changed event is generated. See "Concepts - Drag Sensors" for more details on autoOffset and offset_changed .

If the angle between the bearing vector and the local Y axis of the SoVRMLCylinderSensor is greater than or equal to diskAngle, then the sensor behaves like a cylinder or rolling pin. The shortest distance between the point of intersection (between the bearing and the sensor's geometry) and the Y axis of the parent group's local coordinate system determines the radius of an invisible cylinder used to map pointing device motion, and mark the zero rotation value. For each subsequent position of the bearing, a rotation_changed event is output which corresponds to a relative rotation from the original intersection, plus the offset value. trackPoint_changed events reflect the unclamped drag position on the surface of this cylinder. When the pointing device is deactivated and autoOffset is true, offset is set to the last rotation angle and an offset_changed event is generated. See "Concepts - Drag Sensors" for more details.

When the sensor generates an isActive true event, it grabs all further motion events from the pointing device until it releases and generates an isActive false event (other pointing device sensors cannot generate events during this time). Motion of the pointing device while isActive is true is referred to as a "drag". If a 2D pointing device is in use, isActive events will typically reflect the state of the primary button associated with the device (i.e., isActive is true when the primary button is pressed, and false when not released). If a 3D pointing device (e.g. wand) is in use, isActive events will typically reflect whether the pointer is within or in contact with the sensor's geometry.

While the pointing device is activated, trackPoint_changed and rotation_changed events are output and are interpreted from pointing device motion based on the sensor's local coordinate system at the time of activation. trackPoint_changed events represent the unclamped intersection points on the surface of the invisible cylinder or disk. If the initial angle results in cylinder rotation (as opposed to disk behavior) and if the pointing device is dragged off the cylinder while activated, browsers may interpret this in several ways (e.g. clamp all values to the cylinder, continue to rotate as the point is dragged away from the cylinder, etc.). Each movement of the pointing device, while isActive is true, generates trackPoint_changed and rotation_changed events.

minAngle and maxAngle may be set to clamp rotation_changed events to a range of values (measured in radians about the local Z and Y axis as appropriate). If minAngle is greater than maxAngle, rotation_changed events are not clamped.

See "Concepts - Pointing Device Sensors and Drag Sensors" for more details.

FILE FORMAT/DEFAULT

VRMLCylinderSensor {

autoOffset	true
diskAngle	0.262
enabled	true
maxAngle	-1
minAngle	0
offset	0
description	""
metadata	NULL

}

EVENTS

eventIn

SoSFBool	set_autoOffset
SoSFFloat	set_diskAngle
SoSFBool	set_enabled
SoSFFloat	set_maxAngle
SoSFFloat	set_minAngle
SoSFFloat	set_offset
SoSFString	set_description
SoSFNode	set_metadata

eventOut

SoSFBool	isActive
SoSFBool	isOver
SoSFRotation	rotation_changed
SoSFVec3f	trackPoint_changed
SoSFBool	autoOffset_changed
SoSFFloat	diskAngle_changed
SoSFBool	enabled_changed
SoSFFloat	maxAngle_changed
SoSFFloat	minAngle_changed
SoSFFloat	offset_changed
SoSFString	description_changed
SoSFNode	metadata_changed

Obsoletesince Open Inventor 9500 The VRML API is no longer supported. See section http://oivdoc95.vsg3d.com/content/compatibility-notes-4#Deprecation of the Reference Manual.

Reference