TxFunction Class Reference

#include <TxFunction.h>

List of all members.

Public Member Functions
	TxFunction (float x1, float y1, float x2, float y2)
void	addControlPoint (GLfloat x, GLfloat y, GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha)
void	removeControlPoint (TxPoint *p)
void	moveControlPoint (TxPoint *point, GLfloat x, GLfloat y)
TxPoint *	hitTxPoint (GLfloat x, GLfloat y)
TxPoint *	getLastTxPoint ()
TxPoint *	getFirstTxPoint ()
void	render ()
TxPoint *	getNearestNeighbour (unsigned short density)
void	getLinearInterpolatedColor (unsigned short density, float &red, float &green, float &blue, float &alpha)

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Detailed Description

This file defines a Transferfunction. A transferfunction is made of controlpoints and lines between them. The control points here are stored in a vector. To add a controlpoint, simply call the addControlPoint method.

Version:

12-04-2005

Definition at line 17 of file TxFunction.h.

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Constructor & Destructor Documentation

TxFunction::TxFunction (  float  x1, float  y1, float  x2, float  y2 )

The contructor the tranferfunction creates a function with 2 controlpoints - at the beginning and at the end. The controlpoints are usually given by the histogram dimensions. Parameters: x1  the x coordinate of the first control point y1  the y coordinate of the first control point x2  the x coordinate of the second control point y2  the y coordinate of the second control point

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Member Function Documentation

void TxFunction::addControlPoint (  GLfloat  x, GLfloat  y, GLfloat  red, GLfloat  green, GLfloat  blue, GLfloat  alpha )

Add a controlPoint to the vector wich holds the TxPoints. The function should only be called after the check. Parameters: x  the x coordinate of the control point y  the y coordinate of the control point red  color part green  color part blue  color part alpha  value Referenced by Histogram::onLeftMouseClick().

TxPoint * TxFunction::getFirstTxPoint (   )

Retrieve the first point Definition at line 37 of file TxFunction.cpp.

TxPoint * TxFunction::getLastTxPoint (   )

Retrieve the last point Definition at line 32 of file TxFunction.cpp.

void TxFunction::getLinearInterpolatedColor (  unsigned short  density, float &  red, float &  green, float &  blue, float &  alpha )

Find the linear interpolated color of a given density. The method searches for the controlpoint that is next to the given density using the getNearestNeighbour method. Afterwards it calculates the distance to the two next neighbours and assigns the weighted color values to red, green, blue and alpha. Parameters: red  component of the resulting color green  component of the resulting color blue  component of the resulting color alpha  component of the resulting color Definition at line 103 of file TxFunction.cpp. References getNearestNeighbour(), TxPoint::position, and TxPoint::rgba. Referenced by Histogram::getColorByDensity().

TxPoint * TxFunction::getNearestNeighbour (  unsigned short  density  )

Find the next greater neighbour for a given density. This will also determine the Definition at line 90 of file TxFunction.cpp. Referenced by getLinearInterpolatedColor().

TxPoint* TxFunction::hitTxPoint (  GLfloat  x, GLfloat  y )

Check if the point is already in the function. This function is called each time before the user adds a point Returns: TxPoint* the point wich was slapped Referenced by Histogram::onLeftMouseClick().

void TxFunction::moveControlPoint (  TxPoint *  point, GLfloat  x, GLfloat  y )

Update the coordinates of a given controlpoint. Parameters: *point  a valid point in the transferfunction list x  coodinate to move to y  coordinate to move to Definition at line 42 of file TxFunction.cpp. References TxPoint::moveTo(). Referenced by Histogram::onMouseDrag().

void TxFunction::removeControlPoint (  TxPoint *  p  )

Remove the given controlPoint from the list, if it is not the end or starting point of the transfer function. Parameters: *p  a refernce to the point that should be removed Definition at line 62 of file TxFunction.cpp. Referenced by Histogram::removeControlPoint().

void TxFunction::render (   )

This function draws the shape of the transfer function. Definition at line 73 of file TxFunction.cpp. References TxPoint::render(). Referenced by Histogram::render().

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

• D:/Study/9.Semester/Visualisierung/Lu/1/final5/TxFunction.h
• D:/Study/9.Semester/Visualisierung/Lu/1/final5/TxFunction.cpp

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