SoPolygonScreenDrawer Class Reference
[Drawers]

Interactively draws a polygon in normalized screen space. More...

#include <Inventor/drawers/SoPolygonScreenDrawer.h>

Inheritance diagram for SoPolygonScreenDrawer:

List of all members.

Public Member Functions
virtual SoType	getTypeId () const
	SoPolygonScreenDrawer ()
virtual void	clear ()
Static Public Member Functions
static SoType	getClassTypeId ()

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Detailed Description

Interactively draws a polygon in normalized screen space.

This class can be used to interactively draw a polygon on screen.

When the polygon 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 additional notes and code example.

Polygon specific notes:

• The simplificationThreshold field does apply to this node.

• If the user finishes a polygon and the application does not call the clear() method, then the next click will add another point to the existing polygon.

• SbEventHandlers:
  • OnStart : Triggered on initial LeftMouseDown input event.
  • OnMove : Triggered on MouseMove input events (after Start)
    and also on LeftMouseDown and LeftMouseUp input events (after Start).
  • OnFinish : Triggered on LeftMouseDoubleClick input event
    or KeyPress input event with <Enter> or <ESC> keys.

[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

• Left click to add a point.
• Double-click to add a point and finish the polygon.
• Press Enter to finish the polygon (with the points added so far).
• Press Escape to cancel creation of the polygon.

FILE FORMAT/DEFAULT

PolygonScreenDrawer {

point	[]
color	1 0 0
simplificationThreshold	5
isClosed	TRUE

}

SEE ALSO

SoEllipseScreenDrawer, SoLassoScreenDrawer, SoPolyLineScreenDrawer, SoRectangleScreenDrawer

See related examples:

CustomScreenDrawer, MedicalFreeHandCutting, CSGClippingGroup, EditingPicking

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Constructor & Destructor Documentation

SoPolygonScreenDrawer::SoPolygonScreenDrawer

(

)

Constructor.

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Member Function Documentation

virtual void SoPolygonScreenDrawer::clear

(

)

[inline, virtual]

Convenience method to clear the points in the line.

Reimplemented from SoPolyLineScreenDrawer.

static SoType SoPolygonScreenDrawer::getClassTypeId

(

)

[static]

Returns the type identifier for this class.

Reimplemented from SoPolyLineScreenDrawer.

virtual SoType SoPolygonScreenDrawer::getTypeId

(

)

const [virtual]

Returns the type identifier for this specific instance.

Reimplemented from SoPolyLineScreenDrawer.

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

• Inventor/drawers/SoPolygonScreenDrawer.h