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10 jab 1 
#include <typeinfo>
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#include <iostream>
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#include "CGLA/Mat4x4f.h"
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#include "CGLA/Mat2x2f.h"
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#include "CGLA/Vec2f.h"
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#include "CGLA/Vec2i.h"
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#include "CGLA/Vec3i.h"
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#include "CGLA/Vec3f.h"
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#include "CGLA/Vec3Hf.h"
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#include <GL/glut.h>
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using namespace CGLA;
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Mat4x4f perspective_Mat4x4f(float d)
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{
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  Mat4x4f m(0.0f);
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  /* Eye at the origin, looking down the negative z axis */
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  m[0][0] = 1.0;
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  m[1][1] = 1.0;
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  m[2][2] = 1.0;
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  m[3][2] = -1.0/d;
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  return m;
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}
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static void display( void )
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{
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  // ----------------------------------------
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  // 0. Set up viewing parameters
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  Vec3f up(0,1,0);             // The direction that is most nearly up ..
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  Vec3f eye(3,3,3);            // position of eye
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  Vec3f centre(0,0,0);         // what we are looking at
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  float image_plane_dist = 1;  // distance from eye to image plane.
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  // ----------------------------------------
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  // 1. Create view coordinate system
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  //
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  // Note that the args in the cross(.,.) call
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  // do not commute
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  Vec3f n = centre - eye;
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  n.normalize();
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  Vec3f u = cross(n,up);
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  u.normalize();
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  Vec3f v = cross(u,n);
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  //----------------------------------------
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  // 2. Create matrices
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  // Create viewing matrix. We use the basis change method.
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  // Notice how the direction of z is flipped. That is because
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  // we look down the -z direction
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  Mat4x4f mview(Vec3Hf(u,0), Vec3Hf(v,0), Vec3Hf(-n,0), Vec3Hf());
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  //Create translation matrix.
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  Mat4x4f mtrans = translation_Mat4x4f(centre-eye);
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  // Create projection matrix
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  Mat4x4f mpers  = perspective_Mat4x4f(image_plane_dist);
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  // Concatenate the translation, viewing and projection matrices
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  Mat4x4f m = mpers * mview * mtrans;
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	std::cout << mview << mtrans << mpers << m << std::endl;
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  //----------------------------------------
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  // 3. Create points
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  Vec3Hf axes[3]={Vec3Hf(2,0,0),Vec3Hf(0,2,0),Vec3Hf(0,0,2)};
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  Vec3Hf paxes[3];
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  Vec3Hf p[9] ={Vec3Hf(0,0,0), Vec3Hf(1,0,0), Vec3Hf(0,1,0),
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		Vec3Hf(1,1,0), Vec3Hf(0,0,1), Vec3Hf(1,0,1),
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		Vec3Hf(0,1,1), Vec3Hf(1,1,1)};
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  Vec3Hf pp[9];
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  //----------------------------------------
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  // 4. project and dehomogenize points
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  paxes[0] = m * axes[0];
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  paxes[1] = m * axes[1];
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  paxes[2] = m * axes[2];
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  paxes[0].de_homogenize();
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  paxes[1].de_homogenize();
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  paxes[2].de_homogenize();
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  for (int i=0;i<9;i++)
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    {
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      pp[i] = m * p[i];
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      pp[i].de_homogenize();
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    }
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  //----------------------------------------
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  // 5. Draw _projected_ points in 2D using OpenGL
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  // Clear screen
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  glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
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  glBegin(GL_LINES);
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  glColor3f(1,0,0);
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  glVertex2fv(pp[0].get());
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  glVertex2fv(paxes[0].get());
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  glColor3f(0,1,0);
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  glVertex2fv(pp[0].get());
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  glVertex2fv(paxes[1].get());
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  glColor3f(0,0,1);
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  glVertex2fv(pp[0].get());
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  glVertex2fv(paxes[2].get());
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  glColor3f(0,0,0);
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  for(int i=0;i<4;i++)
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    {
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      glVertex2fv(pp[2*i           + 0 ].get());
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      glVertex2fv(pp[2*i           + 1 ].get());
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    }
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  for(int i=0;i<4;i++)
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    {
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      glVertex2fv(pp[(4*(i/2) + i%2) + 0 ].get());
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      glVertex2fv(pp[(4*(i/2) + i%2) + 2 ].get());
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    }
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  for(int i=0;i<4;i++)
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    {
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      glVertex2fv(pp[1*i           + 0 ].get());
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      glVertex2fv(pp[1*i           + 4 ].get());
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    }
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  glEnd();
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	glFlush();
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}
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static void reshape( int width, int height )
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{
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  glViewport( 0, 0, width, height );
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}
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static void key( unsigned char key, int x, int y )
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{
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  switch (key) {
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  case 27:
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    exit(0);
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    break;
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  }
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}
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static void init_GL()
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{
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  // Initialize GL, i.e. setup projection
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  // and possibly other things as well
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  glClearColor(1,1,1,1);
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  gluOrtho2D(-3,3,-3,3);
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}
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static void init_GLUT(int argc, char *argv[])
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{
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  // Initialize glut, open and create window.
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  glutInit( &argc, argv );
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  glutInitWindowSize( 400 , 400 );
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  glutCreateWindow(argv[0]);
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  // Register callback functions
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  glutReshapeFunc( reshape );
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  glutKeyboardFunc( key );
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  glutDisplayFunc( display );
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}
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int main( int argc, char *argv[] )
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{
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  init_GLUT(argc, argv);
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  init_GL();
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  glutMainLoop();
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  return 0;
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}
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