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/* $Id: texcyl.c,v 1.1 1999/08/19 00:55:40 jtg Exp $ */
/*
* Textured cylinder demo: lighting, texturing, reflection mapping.
* Brian Paul May 1997 This program is in the public domain.
*/
/*
* $Log: texcyl.c,v $
* Revision 1.1 1999/08/19 00:55:40 jtg
* Initial revision
*
* Revision 3.3 1999/03/28 18:24:37 brianp
* minor clean-up
*
* Revision 3.2 1998/11/05 04:34:04 brianp
* moved image files to ../images/ directory
*
* Revision 3.1 1998/06/23 03:16:51 brianp
* added Point/Linear sampling menu items
*
* Revision 3.0 1998/02/14 18:42:29 brianp
* initial rev
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <GL/glut.h>
#include "../util/readtex.c" /* I know, this is a hack. */
#define TEXTURE_FILE "../images/reflect.rgb"
#define LIT 1
#define TEXTURED 2
#define REFLECT 3
#define ANIMATE 10
#define POINT_FILTER 20
#define LINEAR_FILTER 21
#define QUIT 100
static GLuint CylinderObj = 0;
static GLboolean Animate = GL_TRUE;
static GLfloat Xrot = 0.0, Yrot = 0.0, Zrot = 0.0;
static GLfloat DXrot = 1.0, DYrot = 2.5;
static void Idle( void )
{
if (Animate) {
Xrot += DXrot;
Yrot += DYrot;
glutPostRedisplay();
}
}
static void Display( void )
{
glClear( GL_COLOR_BUFFER_BIT );
glPushMatrix();
glRotatef(Xrot, 1.0, 0.0, 0.0);
glRotatef(Yrot, 0.0, 1.0, 0.0);
glRotatef(Zrot, 0.0, 0.0, 1.0);
glScalef(5.0, 5.0, 5.0);
glCallList(CylinderObj);
glPopMatrix();
glutSwapBuffers();
}
static void Reshape( int width, int height )
{
glViewport( 0, 0, width, height );
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
glFrustum( -1.0, 1.0, -1.0, 1.0, 10.0, 100.0 );
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
glTranslatef( 0.0, 0.0, -70.0 );
}
static void SetMode(GLuint m)
{
/* disable everything */
glDisable(GL_LIGHTING);
glDisable(GL_TEXTURE_2D);
glDisable(GL_TEXTURE_GEN_S);
glDisable(GL_TEXTURE_GEN_T);
/* enable what's needed */
if (m==LIT) {
glEnable(GL_LIGHTING);
}
else if (m==TEXTURED) {
glEnable(GL_TEXTURE_2D);
}
else if (m==REFLECT) {
glEnable(GL_TEXTURE_2D);
glEnable(GL_TEXTURE_GEN_S);
glEnable(GL_TEXTURE_GEN_T);
}
}
static void ModeMenu(int entry)
{
if (entry==ANIMATE) {
Animate = !Animate;
}
else if (entry==POINT_FILTER) {
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
}
else if (entry==LINEAR_FILTER) {
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}
else if (entry==QUIT) {
exit(0);
}
else {
SetMode(entry);
}
glutPostRedisplay();
}
static void Key( unsigned char key, int x, int y )
{
(void) x;
(void) y;
switch (key) {
case 27:
exit(0);
break;
}
glutPostRedisplay();
}
static void SpecialKey( int key, int x, int y )
{
float step = 3.0;
(void) x;
(void) y;
switch (key) {
case GLUT_KEY_UP:
Xrot += step;
break;
case GLUT_KEY_DOWN:
Xrot -= step;
break;
case GLUT_KEY_LEFT:
Yrot += step;
break;
case GLUT_KEY_RIGHT:
Yrot -= step;
break;
}
glutPostRedisplay();
}
static void Init( void )
{
GLUquadricObj *q = gluNewQuadric();
CylinderObj = glGenLists(1);
glNewList(CylinderObj, GL_COMPILE);
glTranslatef(0.0, 0.0, -1.0);
/* cylinder */
gluQuadricNormals(q, GL_SMOOTH);
gluQuadricTexture(q, GL_TRUE);
gluCylinder(q, 0.6, 0.6, 2.0, 24, 1);
/* end cap */
glTranslatef(0.0, 0.0, 2.0);
gluDisk(q, 0.0, 0.6, 24, 1);
/* other end cap */
glTranslatef(0.0, 0.0, -2.0);
gluQuadricOrientation(q, GLU_INSIDE);
gluDisk(q, 0.0, 0.6, 24, 1);
glEndList();
gluDeleteQuadric(q);
/* lighting */
glEnable(GL_LIGHTING);
{
GLfloat gray[4] = {0.2, 0.2, 0.2, 1.0};
GLfloat white[4] = {1.0, 1.0, 1.0, 1.0};
GLfloat teal[4] = { 0.0, 1.0, 0.8, 1.0 };
glMaterialfv(GL_FRONT, GL_DIFFUSE, teal);
glLightfv(GL_LIGHT0, GL_AMBIENT, gray);
glLightfv(GL_LIGHT0, GL_DIFFUSE, white);
glEnable(GL_LIGHT0);
}
/* fitering = nearest, initially */
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST);
glTexGeni(GL_S, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP);
glTexGeni(GL_T, GL_TEXTURE_GEN_MODE, GL_SPHERE_MAP);
if (!LoadRGBMipmaps(TEXTURE_FILE, GL_RGB)) {
printf("Error: couldn't load texture image\n");
exit(1);
}
glEnable(GL_CULL_FACE); /* don't need Z testing for convex objects */
SetMode(LIT);
}
int main( int argc, char *argv[] )
{
glutInit( &argc, argv );
glutInitWindowSize( 400, 400 );
glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
glutCreateWindow(argv[0] );
Init();
glutReshapeFunc( Reshape );
glutKeyboardFunc( Key );
glutSpecialFunc( SpecialKey );
glutDisplayFunc( Display );
glutIdleFunc( Idle );
glutCreateMenu(ModeMenu);
glutAddMenuEntry("Lit", LIT);
glutAddMenuEntry("Textured", TEXTURED);
glutAddMenuEntry("Reflect", REFLECT);
glutAddMenuEntry("Point Filtered", POINT_FILTER);
glutAddMenuEntry("Linear Filtered", LINEAR_FILTER);
glutAddMenuEntry("Toggle Animation", ANIMATE);
glutAddMenuEntry("Quit", QUIT);
glutAttachMenu(GLUT_RIGHT_BUTTON);
glutMainLoop();
return 0;
}
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