RETOUR
Le source : PlacageTextureSurCylindre.cpp
/* Une molecule de benzene : C6H6 */
/* */
/* Auteur: Nicolas JANEY */
/* nicolas.janey@univ-fcomte.fr */
/* Septembre 2011 */
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <GL/glut.h>
#include <GL/gl.h>
#include <GL/glu.h>
/* Variables et constantes globales */
#ifndef M_PI
#define M_PI 3.14159
#endif
static const float blanc[] = { 1.0F,1.0F,1.0F,1.0F };
static const float gris[] = { 0.7F,0.7F,0.7F,1.0F };
static float rx = 0.0F;
static float ry = 0.0F;
static float rz = 0.0F;
static int objet = 0;
static int aff = 1;
GLbyte *lireImageRaw(int tx,int ty,char *filename) {
GLbyte *img = NULL;
FILE *file = fopen(filename,"rb");
if ( file ) {
img =(GLbyte *) calloc(tx*ty*3,sizeof(GLbyte));
fread(img,1,tx*ty*3,file);
fclose(file); }
return(img);
}
/* Fonction executee lors de la frappe */
/* d'une touche du clavier */
void keyboard(unsigned char key,int x,int y) {
switch ( key ) {
case 0x20 :
aff = (aff+1)%2;
glutPostRedisplay();
break;
case 0x0D :
objet = (objet+1)%2;
glutPostRedisplay();
break;
case 0x1B :
exit(0);
break; }
}
/* Fonction executee lors de l'appui */
/* d'une touche de curseur ou d'une touche */
/* page up ou page down */
void special(int key,int x,int y) {
switch(key) {
case GLUT_KEY_UP :
rx++;
glutPostRedisplay();
break;
case GLUT_KEY_DOWN :
rx--;
glutPostRedisplay();
break;
case GLUT_KEY_LEFT :
ry++;
glutPostRedisplay();
break;
case GLUT_KEY_RIGHT :
ry--;
glutPostRedisplay();
break;
case GLUT_KEY_PAGE_UP :
rz++;
glutPostRedisplay();
break;
case GLUT_KEY_PAGE_DOWN :
rz--;
glutPostRedisplay();
break; }
}
/* Fonction d'initialisation des parametres */
/* OpenGL ne changeant pas au cours de la vie */
/* du programme */
void init(void) {
const GLfloat mat_shininess[] = { 50.0 };
glMaterialfv(GL_FRONT,GL_SPECULAR,blanc);
glMaterialfv(GL_FRONT,GL_SHININESS,mat_shininess);
glLightfv(GL_LIGHT0,GL_DIFFUSE,gris);
glLightfv(GL_LIGHT1,GL_DIFFUSE,gris);
glLightfv(GL_LIGHT2,GL_DIFFUSE,gris);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glEnable(GL_LIGHT1);
glEnable(GL_LIGHT2);
glDepthFunc(GL_LESS);
glEnable(GL_DEPTH_TEST);
glEnable(GL_NORMALIZE);
glEnable(GL_AUTO_NORMAL);
// glEnable(GL_CULL_FACE);
GLbyte *image = lireImageRaw(16,16,"Damier.raw");
if ( image ) {
glPixelStorei(GL_UNPACK_ALIGNMENT,1);
glTexImage2D(GL_TEXTURE_2D,0,3,16,16,0,GL_RGB,GL_UNSIGNED_BYTE,image);
free(image);
glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST);
glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST);
glEnable(GL_TEXTURE_2D); }
}
/* Scene dessinee */
void mySolidCylinder(float hauteur,float rayon,int ns,int nl) {
GLboolean nm = glIsEnabled(GL_NORMALIZE);
if ( !nm )
glEnable(GL_NORMALIZE);
float normale[4];
glGetFloatv(GL_CURRENT_NORMAL,normale);
glPushMatrix();
for ( int j = 0 ; j < nl ; j++ ) {
float hi = hauteur/2-j*hauteur/nl;
float si =(float) j/nl;
float hf = hi-hauteur/nl;
float sf =(float) (j+1)/nl;
glBegin(GL_QUAD_STRIP);
for( int i = 0 ; i <= ns ; i++ ) {
float a = (2*M_PI*i)/ns;
float t =(float) i/ns;
float cs = cos(a);
float sn = -sin(a);
glNormal3f(cs,0.0F,sn);
float x = rayon*cs;
float z = rayon*sn;
glTexCoord2f(si,t);
glVertex3f(x,hi,z);
glTexCoord2f(sf,t);
glVertex3f(x,hf,z); }
glEnd(); }
glPopMatrix();
glNormal3f(normale[0],normale[1],normale[2]);
if ( !nm )
glDisable(GL_NORMALIZE);
}
void scene(void) {
glPushMatrix();
mySolidCylinder(3.5F,1.7F,36,5);
glPopMatrix();
}
/* Fonction executee lors d'un rafraichissement */
/* de la fenetre de dessin */
void display(void) {
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
const GLfloat light0_position[] = { 1.0,1.0,1.0,0.0 };
const GLfloat light1_position[] = { -1.0,1.0,1.0,0.0 };
const GLfloat light2_position[] = { 1.0,-1.0,1.0,0.0 };
glLightfv(GL_LIGHT0,GL_POSITION,light0_position);
glLightfv(GL_LIGHT1,GL_POSITION,light1_position);
glLightfv(GL_LIGHT2,GL_POSITION,light2_position);
glPolygonMode(GL_FRONT_AND_BACK,(aff) ? GL_FILL : GL_LINE);
glPushMatrix();
glRotatef(rx,1.0F,0.0F,0.0F);
glRotatef(ry,0.0F,1.0F,0.0F);
glRotatef(rz,0.0F,0.0F,1.0F);
scene();
glPopMatrix();
glFlush();
glutSwapBuffers();
int error = glGetError();
if ( error != GL_NO_ERROR )
printf("Erreur OpenGL: %d\n",error);
}
/* Fonction executee lors d'un changement */
/* de la taille de la fenetre OpenGL */
/* -> Ajustement de la camera de visualisation */
void reshape(int x,int y) {
glViewport(0,0,x,y);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(20.0F,(float) x/y,1.0,50.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt(0.0,10.0,15.0,0.0,0.0,0.0,0.0,1.0,0.0);
}
/* Fonction principale */
int main(int argc,char **argv) {
glutInit(&argc,argv);
glutInitDisplayMode(GLUT_RGBA|GLUT_DEPTH|GLUT_DOUBLE);
glutInitWindowSize(300,300);
glutInitWindowPosition(50,50);
glutCreateWindow("Un cylindre texturé");
init();
glutKeyboardFunc(keyboard);
glutSpecialFunc(special);
glutReshapeFunc(reshape);
glutDisplayFunc(display);
glutMainLoop();
return(0);
}