SoEllipseScreenDrawer Class Reference
[Drawers]

Interactively draw an ellipse in normalized screen space. More...

#include <Inventor/drawers/SoEllipseScreenDrawer.h>

Inheritance diagram for SoEllipseScreenDrawer:

List of all members.

Public Types
enum	CreationMethod {   CORNER_CORNER,   CENTER_CORNER }
Public Member Functions
virtual SoType	getTypeId () const
	SoEllipseScreenDrawer ()
virtual void	reset ()
Static Public Member Functions
static SoType	getClassTypeId ()
Public Attributes
SoSFEnum	method
SoSFUInt32	nbPoint

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Detailed Description

Interactively draw an ellipse in normalized screen space.

This class can be used to interactively draw an ellipse on screen.

When the ellipse 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 is specified by the color field in the parent class SoPolyLineScreenDrawer.

Please see SoPolyLineScreenDrawer for general notes and code example.

Ellipse specific notes:

• The ellipse can be specified by the 2 corners of its bounding box (default) or by its center and one corner of its bounding box (see CreationMethod).

• The simplificationThreshold field does not apply to this node. The number of points in the ellipse is specified using the nbPoint field.

• The isClosed field does apply to this node (but FALSE is not very useful).

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

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

FILE FORMAT/DEFAULT

EllipseScreenDrawer {

point	[]
color	1 0 0
simplificationThreshold	0
isClosed	TRUE
method	CORNER_CORNER
nbPoint	16

}

SEE ALSO

SoLassoScreenDrawer, SoPolyLineScreenDrawer, SoPolygonScreenDrawer, SoRectangleScreenDrawer,

See related examples:

CustomScreenDrawer, MedicalFreeHandCutting, CSGClippingGroup

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Member Enumeration Documentation

enum SoEllipseScreenDrawer::CreationMethod

Methods to create ellipse.

Enumerator:

CORNER_CORNER	Initial point is a corner, current point is a corner.
CENTER_CORNER	Initial point is the center, current point is a corner.

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Constructor & Destructor Documentation

SoEllipseScreenDrawer::SoEllipseScreenDrawer

(

)

Constructor.

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Member Function Documentation

static SoType SoEllipseScreenDrawer::getClassTypeId

(

)

[static]

Returns the type identifier for this class.

Reimplemented from SoPolyLineScreenDrawer.

virtual SoType SoEllipseScreenDrawer::getTypeId

(

)

const [virtual]

Returns the type identifier for this specific instance.

Reimplemented from SoPolyLineScreenDrawer.

virtual void SoEllipseScreenDrawer::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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Member Data Documentation

SoSFEnum SoEllipseScreenDrawer::method

Method to create ellipse.

Use enum CreationMethod. Default is CORNER_CORNER.

SoSFUInt32 SoEllipseScreenDrawer::nbPoint

Number of points in generated ellipse.

Default is 16. Must be > 0.

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

• Inventor/drawers/SoEllipseScreenDrawer.h