opengl简单的视角变换

#include "stdafx.h"
#include 
#include 

static GLdouble axix = 0.0,axiy = 0.0,z = 0.0;
void init(void) 
{
   glClearColor (0.0, 0.0, 0.0, 0.0);
   glShadeModel (GL_FLAT);
}

void display(void)
{
   glClear (GL_COLOR_BUFFER_BIT);
   glColor3f (1.0, 1.0, 1.0);
   glLoadIdentity ();             /* clear the matrix */
           /* viewing transformation  */
   gluLookAt (axix, axiy, z, 0.0, 0.0, 0.0, 1.0, 1.0, 0.0);
   glScalef (1.0, 2.0, 1.0);      /* modeling transformation */ 
   glutWireCube (1.0);
   glFlush ();
}

void reshape (int w, int h)
{
   glViewport (0, 0, (GLsizei) w, (GLsizei) h); 
   glMatrixMode (GL_PROJECTION);
   glLoadIdentity ();
  // glFrustum (-1.0, 1.0, -1.0, 1.0, 1.5, 20.0);
   gluPerspective(60.0,(GLfloat) w/(GLfloat) h,1.5,20.0);
   glMatrixMode (GL_MODELVIEW);
}

void keyboard(unsigned char key, int x, int y)
{
   switch (key) {
	    case 'd':
         axix += 1.0;
         glutPostRedisplay();
         break;
		  case 'a':
         axix -= 1.0;
         glutPostRedisplay();
         break;
		  case 'w':
         z -= 1.0;
         glutPostRedisplay();
         break;
		  case 's':
         z += 1.0;
         glutPostRedisplay();
         break;
      case 27:
         exit(0);
         break;
   }
}

int main(int argc, char** argv)
{
   glutInit(&argc, argv);
   glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
   glutInitWindowSize (500, 500); 
   glutInitWindowPosition (100, 100);
   glutCreateWindow (argv[0]);
   init ();
   glutDisplayFunc(display); 
   glutReshapeFunc(reshape);
   glutKeyboardFunc(keyboard);
   glutMainLoop();
   return 0;
}