OGRE  13.4 Object-Oriented Graphics Rendering Engine
Ogre::SimpleSpline Class Reference

A very simple spline class which implements the Catmull-Rom class of splines. More...

#include <OgreSimpleSpline.h>

## Public Member Functions

SimpleSpline ()

~SimpleSpline ()

Adds a control point to the end of the spline. More...

void clear (void)
Clears all the points in the spline. More...

unsigned short getNumPoints (void) const
Gets the number of control points in the spline. More...

const Vector3getPoint (unsigned short index) const
Gets the detail of one of the control points of the spline. More...

Vector3 interpolate (Real t) const
Returns an interpolated point based on a parametric value over the whole series. More...

Vector3 interpolate (unsigned int fromIndex, Real t) const
Interpolates a single segment of the spline given a parametric value. More...

void recalcTangents (void)
Recalculates the tangents associated with this spline. More...

void setAutoCalculate (bool autoCalc)
Tells the spline whether it should automatically calculate tangents on demand as points are added. More...

void updatePoint (unsigned short index, const Vector3 &value)
Updates a single point in the spline. More...

## Detailed Description

A very simple spline class which implements the Catmull-Rom class of splines.

Splines are bendy lines. You define a series of points, and the spline forms a smoother line between the points to eliminate the sharp angles.

Catmull-Rom splines are a specialisation of the general Hermite spline. With a Hermite spline, you define the start and end point of the line, and 2 tangents, one at the start of the line and one at the end. The Catmull-Rom spline simplifies this by just asking you to define a series of points, and the tangents are created for you.

## ◆ SimpleSpline()

 Ogre::SimpleSpline::SimpleSpline ( )

## ◆ ~SimpleSpline()

 Ogre::SimpleSpline::~SimpleSpline ( )

## Member Function Documentation

 void Ogre::SimpleSpline::addPoint ( const Vector3 & p )

Adds a control point to the end of the spline.

## ◆ getPoint()

 const Vector3& Ogre::SimpleSpline::getPoint ( unsigned short index ) const

Gets the detail of one of the control points of the spline.

## ◆ getNumPoints()

 unsigned short Ogre::SimpleSpline::getNumPoints ( void ) const

Gets the number of control points in the spline.

## ◆ clear()

 void Ogre::SimpleSpline::clear ( void )

Clears all the points in the spline.

## ◆ updatePoint()

 void Ogre::SimpleSpline::updatePoint ( unsigned short index, const Vector3 & value )

Updates a single point in the spline.

This point must already exist in the spline.

## ◆ interpolate() [1/2]

 Vector3 Ogre::SimpleSpline::interpolate ( Real t ) const

Returns an interpolated point based on a parametric value over the whole series.

Given a t value between 0 and 1 representing the parametric distance along the whole length of the spline, this method returns an interpolated point.

Parameters
 t Parametric value.

## ◆ interpolate() [2/2]

 Vector3 Ogre::SimpleSpline::interpolate ( unsigned int fromIndex, Real t ) const

Interpolates a single segment of the spline given a parametric value.

Parameters
 fromIndex The point index to treat as t=0. fromIndex + 1 is deemed to be t=1 t Parametric value

## ◆ setAutoCalculate()

 void Ogre::SimpleSpline::setAutoCalculate ( bool autoCalc )

Tells the spline whether it should automatically calculate tangents on demand as points are added.

The spline calculates tangents at each point automatically based on the input points. Normally it does this every time a point changes. However, if you have a lot of points to add in one go, you probably don't want to incur this overhead and would prefer to defer the calculation until you are finished setting all the points. You can do this by calling this method with a parameter of 'false'. Just remember to manually call the recalcTangents method when you are done.

Parameters
 autoCalc If true, tangents are calculated for you whenever a point changes. If false, you must call reclacTangents to recalculate them when it best suits.

## ◆ recalcTangents()

 void Ogre::SimpleSpline::recalcTangents ( void )

Recalculates the tangents associated with this spline.

If you tell the spline not to update on demand by calling setAutoCalculate(false) then you must call this after completing your updates to the spline points.

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