SoLassoScreenDrawer Class Reference
[Drawers]

Interactively draw a lasso in normalized screen space. More...

#include <Inventor/drawers/SoLassoScreenDrawer.h>

Inheritance diagram for SoLassoScreenDrawer:

List of all members.

Public Member Functions
virtual SoType	getTypeId () const
	SoLassoScreenDrawer ()
virtual void	reset ()
Static Public Member Functions
static SoType	getClassTypeId ()

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Detailed Description

Interactively draw a lasso in normalized screen space.

This class can be used to interactively draw a lasso (freeform shape) on screen.

When the lasso is finished, an event is raised to notify the application (see SoPolyLineScreenDrawer::onFinish ). Points are returned as normalized coordinates in the range -1..1, which is conveniently the default view volume for an SoOrthographicCamera node.

The line color and simplification threshold are specified by fields in the parent class SoPolyLineScreenDrawer.

Please see SoPolyLineScreenDrawer for general notes and code example.

Lasso specific notes:

• The simplificationThreshold field does apply to this node.

• If user finishes a lasso, then the next click will automatically clear the polyline (begin a new lasso).

• SbEventHandlers:
  • OnStart : Triggered on LeftMouseDown input event.
  • OnMove : Triggered on MouseMove input events (after Start).
  • OnFinish : Triggered on LeftMouseUp input event.

[C++]
Screen drawer classes must be initialized by calling SoInteraction::init(). High level viewer init methods, like SoWin::init(), automatically do this. However, if the application is calling SoDB::init() directly, then it is usually necessary to also call SoInteraction::init() before using the screen drawer classes.

USAGE

• Press left mouse and drag to draw the lasso.
• Release to finish the lasso.
• Press Escape to cancel construction of the lasso.

FILE FORMAT/DEFAULT

LassoScreenDrawer {

point	[]
color	1 0 0
simplificationThreshold	5
isClosed	TRUE

}

SEE ALSO

SoEllipseScreenDrawer, SoPolyLineScreenDrawer, SoPolygonScreenDrawer, SoRectangleScreenDrawer

See related examples:

CustomScreenDrawer, MedicalFreeHandCutting, CSGClippingGroup, EditingExtrusion, Editing

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Constructor & Destructor Documentation

SoLassoScreenDrawer::SoLassoScreenDrawer

(

)

Constructor.

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Member Function Documentation

static SoType SoLassoScreenDrawer::getClassTypeId

(

)

[static]

Returns the type identifier for this class.

Reimplemented from SoPolyLineScreenDrawer.

virtual SoType SoLassoScreenDrawer::getTypeId

(

)

const [virtual]

Returns the type identifier for this specific instance.

Reimplemented from SoPolyLineScreenDrawer.

virtual void SoLassoScreenDrawer::reset

(

)

[virtual]

Clears the points in the line and resets internal state to initial values. This cancels any current drawing. Since Open Inventor 10.7.3

Reimplemented from SoPolyLineScreenDrawer.

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The documentation for this class was generated from the following file:

• Inventor/drawers/SoLassoScreenDrawer.h