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glutils.hpp

//============================================================================
// glutils.cpp : OpenGL handy rendering utilities
//============================================================================
#ifndef GL_UTILS_HPP
#define GL_UTILS_HPP
#include <GL/glut.h>
#include <stdio.h>

void DisplayMinMaxBox(float Min[3], float Max[3], 
                      float r=1, float g=1, float b=1, float LineWidth=1);

void GLerror(char *msg);


// Convert depth buffer values into euclidean Z
inline float LinearizeZ(float DepthZ, float NearDist, float FarDist)
{
  return (NearDist*FarDist) / ( FarDist - DepthZ*(FarDist-NearDist) ); 
}

// Convert euclidean Z into depth buffer values
inline float DepthifyZ(float LinearZ, float NearDist, float FarDist)
{
  return ((FarDist*(LinearZ-NearDist))/ ( LinearZ*(FarDist-NearDist) ) ); 
}
#endif

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