AlBlendPoint

Interface to Alias blend points.

SYNOPSIS

#include <AlBlendPoint.h>

class AlBlendPoint :	public AlObject

enum AlConstraintContinuityType
{
	kG0,
	kG1,
	kG2,
	kG3,
	kG4
};
enum AlCurvatureType
{
	kGeometricCurv,
	kParametric
};
enum AlInterpolationDirectionType
{
	kLocation,
	kWorldSpace,
	kGeometricInterp
};

enum AlDirectionType
{
	kRay,
	kParallel
};

AlBlendPoint();
virtual		~AlBlendPoint();
virtual statusCode		deleteObject();
virtual AlObject*		copyWrapper() const;
virtual AlObjectType		type() const;
statusCode		setPoint( double , double , double  );
statusCode		point( double& , double& , double&  );
statusCode 		param( double& );
statusCode		tangent( double&, double&, double& );
statusCode		setTangent( double, double, double );
statusCode		interpolationDirectionType( 
AlInterpolationDirectionType& );
statusCode		setInterpolationDirectionType( 
AlInterpolationDirectionType );
statusCode		directionType( AlDirectionType& );
statusCode		setDirectionType( AlDirectionType );
statusCode		curvatureType( AlCurvatureType& );
statusCode		setCurvatureType( AlCurvatureType );
statusCode		constraintContinuityType( 
AlConstraintContinuityType& );
statusCode		setConstraintContinuityType( 
AlConstraintContinuityType );
statusCode		attachConstraint( AlSurface *, double, 
double );
statusCode		attachConstraint( AlCurve *, double );
statusCode		attachConstraint( AlCurveOnSurface *, 
double );
statusCode		disassociateConstraint();
statusCode		attachedTo( AlObject *&, double&, double& 
);
boolean		isMaster();
statusCode		makeMaster();
AlBlendCurve*		blendCurve();
AlBlendPoint*		next();
statusCode		nextD( AlBlendPoint * );
AlBlendPoint*		prev();
statusCode		prevD( AlBlendPoint * );

DESCRIPTION

Alias Blend Curves contain of Alias Blend Points. Blend Points have constraints and curvature types as described in the Alias manuals. Methods for getting and setting the tangency, position, constraint continuity and the geometry the point is associated with are included.

Notes: 1. To find the Alias Blend Curve this point is on, use the blendCurve() method. 2. To find the Alias Curve that this point is on find the blend curve, the call the AlBlendCurve::curveNode() method. 3. setPoint() will automatically disassociate a blend point from any geometry it is attached to. 4. Do not rely on the param() value staying the same. It will be modified everytime the curve is also modified. 5. Attaching a point to a cloud is not currently supported. 6. Some of the methods will only work if we have the proper context. For example, the interpolation direction might have to be a certain type to make a method work. 7. Deleting blend points can cause the blend curve to also be deleted. If there are less than two points left, then the blend curve will be deleted automatically by the deleteObject() method.

SUMMARY

AlBlendPoint::AlBlendPoint()

Description:

Null constructor.

AlBlendPoint::~AlBlendPoint()

Description:

Null destructor.

statusCode AlBlendPoint::deleteObject()

Description:

This method deletes a blend point on a blend curve. If there are two blend points left on the curve and one of them is deleted, the blend curve will also be deleted.

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the object was invalid

AlObject *AlBlendPoint::copyWrapper() const

Description:

Returns an exact copy of the blend point wrapper. NULL will be returned if the method fails.

AlObjectType AlBlendPoint::type() const

Description:

Returns the class identifier kBlendPointType.

statusCode AlBlendPoint::setPoint( double x , double y , double z )

Description:

Set the world space location of the blend point. If this curve is associated with geometry then that association is automatically removed.

Arguments:

< x,y,z - new world space location for the blend point.

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

statusCode AlBlendPoint::point( double& x , double& y , double& z )

Description:

Returns the world space location of the blend point

Arguments:

> x,y,z - world space location of the point

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

statusCode AlBlendPoint::param( double& param )

Description:

Return the param or 't' value of this point on the curve. Note: this value will change as the Blend Curve is modified.

Arguments:

> param - the param value of this point

Return codes:

sSuccess - the method succeeded

sFailure - internal failure,

sInvalidObject - the blend point is invalid

statusCode AlBlendPoint::tangent( double& x, double& y, double& z )

Description:

Returns the tangent information for the blend point. This method will only work if this blend point has a world space or geometric interpolation direction.

Arguments:

> x,y,z - the tangent of the blend point

Return codes:

sSuccess - the method succeeded

sFailure - internal failure,

sInvalidObject - the blend point is invalid

sInvalidArgument - cannot ask for tangent information since the point does not have world space orgeometric interpolation set

statusCode AlBlendPoint::setTangent( double x, double y, double z )

Description:

Sets the tangent for the blend point. This method will only work if this blend point has a world space or geometric interpolation direction.

Arguments:

< x,y,z - the new tangent for the point

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

sInvalidArugment - cannot set tangent information since the point is not using world space or geometric interpolation or the tangent vector did not have a direction ( 0, 0 0 ).

statusCode AlBlendPoint::constraintContinuityType(AlBlendPoint::AlConstraintContinuityType& cc )

Description:

Returns the type of constraint continuity that is being used by this blend point. This method works only if we are using location or geometric interpolation directions at this point.

Arguments:

> cc - constraint continuity of the blend curve

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

sInvalidArgument - the blend point is not using location

or geometric interpolation directions

statusCode AlBlendPoint::setConstraintContinuityType( AlConstraintContinuityType cc )

Description:

Sets the type of constraint continuity of this blend point. This method works only if we are using location or geometric interpolation directions at this point.

Arguments:

< cc - constraint continuity of the blend curve

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

sInvalidArgument - the blend point is not using location or geometric interpolation directions

statusCode AlBlendPoint::interpolationDirectionType(AlBlendPoint::AlInterpolationDirectionType& id)

Description:

Returns the interpolation direction of the blend point.

Arguments:

> id - interpolation direction of the blend point

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

statusCode AlBlendPoint::setInterpolationDirectionType( AlInterpolationDirectionType id )

Description:

Sets the interpolation direction of the blend point.

Arguments:

< id - interpolation direction of the blend point

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

statusCode AlBlendPoint::directionType(AlBlendPoint::AlDirectionType& dt)

Description:

Returns the direction type that is being used by this blend point. This method works only if we are using world space or geometric interpolation directions at this point.

Arguments:

> dt - the blend point's direction type

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

sInvalidArgument - the blend point is not using world space or geometric interpolation directions

statusCode AlBlendPoint::setDirectionType( AlDirectionType dt )

Description:

Sets the direction type of this blend point. This method works only if we are using world space or geometric interpolation directions at this point.

Arguments:

< dt - the blend point's direction type

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

sInvalidArgument - the blend point is not using world space or geometric interpolation directions

statusCode AlBlendPoint::curvatureType(AlBlendPoint::AlCurvatureType& ct )

Description:

Returns the curvature type that is being used by this blend point. This method works only if we are using geometric interpolations of geometry and we are attached to a surface with G2 or greater continuity at this point.

Arguments:

> ct - the blend point's direction type

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

sInvalidArgument - the blend point is not using geometric interpolations of geometry and is not attached to a surface with G2 or greater continuity.

statusCode AlBlendPoint::setCurvatureType( AlCurvatureType ct )

Description:

Sets the curvature type that is being used by this blend point. This method works only if we are using geometric interpolations of geometry and we are attached to a surface with G2 or greater continuity at this point.

Arguments:

> ct - the blend point's direction type

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

sInvalidArgument - the blend point is not using geometric interpolations of geometry and is not attached to a surface with G2 or greater continuity.

statusCode AlBlendPoint::attachConstraint( AlSurface *surface, double u, double v )

Description:

Attaches this blend point as a constraint to a surface.

Arguments:

< surface - the surface to attach to

< u,v - position on surface to attach to

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

sInvalidArgument - surface is NULL, or surface is invalid, or u,v is invalid for the surface.

statusCode AlBlendPoint::attachConstraint( AlCurve *curve, double t )

Description:

Attaches this blend point as a constraint to a curve. To attach a blend curve to another, pass the resulting curve of the second blend curve into this method. Note: this method will fail if the AlCurve of the AlBlendCurve of this AlBlendPoint is passed in as an argument.

Arguments:

< curve - the surface to attach to

< t - position on curve to attach to

Return codes:

sSuccess - the method succeeded

sFailure - internal failure, or tried to attach point

to its own curve

sInvalidObject - the blend point is invalid

sInvalidArgument - curve is NULL, or curve is invalid, or t is invalid for the curve.

statusCode AlBlendPoint::attachConstraint( AlCurveOnSurface *cos, double t )

Description:

Attaches this blend point as a constraint to a curve on surface.

Arguments:

< cos - the curve on surface to attach to

< t - position on curve on surface to attach to

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

sInvalidArgument - curve on surface is NULL, or curve on surface is invalid, or t is invalid for the surface.

statusCode AlBlendPoint::disassociateConstraint()

Description:

Disassociates the blend point from geometry it is attached to. The position of the blend curve is not changed by this method

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

statusCode AlBlendPoint::attachedTo( AlObject *&obj, double& p1, double& p2 )

Description:

Returns the object and point of attachment parameterization value.

Arugments:

> obj - the object the blend point is attached to. > p1, p2 - if the object is a surface, both p1 and p2 will be set to the u, v values of the point of attachment. If the object is a curve or curve on surface, p1 will be set to the 't' value of the point of attachment to the curve and p2 will be unused and set to 0.

Return codes:

sSuccess - the method succeeded

sFailure - internal failure

sInvalidObject - the blend point is invalid

boolean AlBlendPoint::isMaster()

Description:

Returns TRUE if this is a master point.

statusCode AlBlendPoint::makeMaster()

Description:

If the current point is a slave, this method will make it a master.

Return codes:

sSuccess - the method succeeded

sFailure - internal failure or point is already a master

sInvalidObject - the blend point is invalid

AlBlendCurve* AlBlendPoint::blendCurve()

Description:

Returns the blend curve this point is associated with.

AlBlendPoint* AlBlendPoint::next()

Description:

Returns the next blend point in the blend curve.

statusCode AlBlendPoint::nextD( AlBlendPoint* blendPoint )

Description:

Destructive method for returning the next blend point on the curve. sFailure is returned if there is no next blend point on the curve.

Arguments:

< blendPoint - the blend point to obtain the next blend point from

Return codes:

sSuccess - the method worked

sFailure - the method failed, could be due to there being no next blend point

sInvalidObject - this blend point is invalid

AlBlendPoint* AlBlendPoint::prev()

Description:

Returns the previous blend point in the blend curve.

statusCode AlBlendPoint::prevD( AlBlendPoint* blendPoint )

Description:

Destructive method for returning the previous blend point on the curve. sFailure is returned if there is no previous blend point on the curve.

Arguments:

< blendPoint - the blend point to obtain the previous blend point from

Return codes:

sSuccess - the method worked

sFailure - the method failed, could be due to there being no previous blend point

sInvalidObject - this blend point is invalid