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/* $Id: multiarb.c,v 1.1.1.1 1999/08/19 00:55:40 jtg Exp $ */
/*
* GL_ARB_multitexture demo
* Brian Paul November 1998 This program is in the public domain.
*/
/*
* $Log: multiarb.c,v $
* Revision 1.1.1.1 1999/08/19 00:55:40 jtg
* Imported sources
*
* Revision 1.3 1999/03/28 18:20:49 brianp
* minor clean-up
*
* Revision 1.2 1998/11/05 04:34:04 brianp
* moved image files to ../images/ directory
*
* Revision 1.1 1998/11/03 01:36:33 brianp
* Initial revision
*
*/
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <GL/glut.h>
#include "../util/readtex.c" /* I know, this is a hack. */
#define TEXTURE_1_FILE "../images/girl.rgb"
#define TEXTURE_2_FILE "../images/reflect.rgb"
#define TEX0 1
#define TEX1 2
#define TEXBOTH 3
#define ANIMATE 10
#define QUIT 100
static GLboolean Animate = GL_TRUE;
static GLfloat Drift = 0.0;
static GLfloat Xrot = 20.0, Yrot = 30.0, Zrot = 0.0;
static void Idle( void )
{
if (Animate) {
Drift += 0.05;
#ifdef GL_ARB_multitexture
glActiveTextureARB(GL_TEXTURE0_ARB);
#endif
glMatrixMode(GL_TEXTURE);
glLoadIdentity();
glTranslatef(Drift, 0.0, 0.0);
glMatrixMode(GL_MODELVIEW);
#ifdef GL_ARB_multitexture
glActiveTextureARB(GL_TEXTURE1_ARB);
#endif
glMatrixMode(GL_TEXTURE);
glLoadIdentity();
glTranslatef(0.0, Drift, 0.0);
glMatrixMode(GL_MODELVIEW);
glutPostRedisplay();
}
}
static void DrawObject(void)
{
glBegin(GL_QUADS);
#ifdef GL_ARB_multitexture
glMultiTexCoord2fARB(GL_TEXTURE0_ARB, 0.0, 0.0);
glMultiTexCoord2fARB(GL_TEXTURE1_ARB, 0.0, 0.0);
glVertex2f(-1.0, -1.0);
glMultiTexCoord2fARB(GL_TEXTURE0_ARB, 2.0, 0.0);
glMultiTexCoord2fARB(GL_TEXTURE1_ARB, 1.0, 0.0);
glVertex2f(1.0, -1.0);
glMultiTexCoord2fARB(GL_TEXTURE0_ARB, 2.0, 2.0);
glMultiTexCoord2fARB(GL_TEXTURE1_ARB, 1.0, 1.0);
glVertex2f(1.0, 1.0);
glMultiTexCoord2fARB(GL_TEXTURE0_ARB, 0.0, 2.0);
glMultiTexCoord2fARB(GL_TEXTURE1_ARB, 0.0, 1.0);
glVertex2f(-1.0, 1.0);
#else
glTexCoord2f(0.0, 0.0);
glVertex2f(-1.0, -1.0);
glTexCoord2f(1.0, 0.0);
glVertex2f(1.0, -1.0);
glTexCoord2f(1.0, 1.0);
glVertex2f(1.0, 1.0);
glTexCoord2f(0.0, 1.0);
glVertex2f(-1.0, 1.0);
#endif
glEnd();
}
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);
DrawObject();
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 );
/*glOrtho( -6.0, 6.0, -6.0, 6.0, 10.0, 100.0 );*/
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
glTranslatef( 0.0, 0.0, -70.0 );
}
static void ModeMenu(int entry)
{
GLboolean enable0 = GL_FALSE, enable1 = GL_FALSE;
if (entry==TEX0) {
enable0 = GL_TRUE;
}
else if (entry==TEX1) {
enable1 = GL_TRUE;
}
else if (entry==TEXBOTH) {
enable0 = GL_TRUE;
enable1 = GL_TRUE;
}
else if (entry==ANIMATE) {
Animate = !Animate;
}
else if (entry==QUIT) {
exit(0);
}
if (entry != ANIMATE) {
#ifdef GL_ARB_multitexture
glActiveTextureARB(GL_TEXTURE0_ARB);
#endif
if (enable0) {
glEnable(GL_TEXTURE_2D);
}
else
glDisable(GL_TEXTURE_2D);
#ifdef GL_ARB_multitexture
glActiveTextureARB(GL_TEXTURE1_ARB);
#endif
if (enable1) {
glEnable(GL_TEXTURE_2D);
}
else
glDisable(GL_TEXTURE_2D);
}
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 )
{
const char *exten = (const char *) glGetString(GL_EXTENSIONS);
if (!strstr(exten, "GL_ARB_multitexture")) {
printf("Sorry, GL_ARB_multitexture not supported by this renderer.\n");
exit(1);
}
/* setup texture env 0 */
#ifdef GL_ARB_multitexture
glActiveTextureARB(GL_TEXTURE0_ARB);
#endif
#ifdef LINEAR_FILTER
/* linear filtering looks much nicer but is much slower for Mesa */
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
#else
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
#endif
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
if (!LoadRGBMipmaps(TEXTURE_1_FILE, GL_RGB)) {
printf("Error: couldn't load texture image\n");
exit(1);
}
/* setup texture env 1 */
#ifdef GL_ARB_multitexture
glActiveTextureARB(GL_TEXTURE1_ARB);
#endif
#ifdef LINEAR_FILTER
/* linear filtering looks much nicer but is much slower for Mesa */
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
#else
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
#endif
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
if (!LoadRGBMipmaps(TEXTURE_2_FILE, GL_RGB)) {
printf("Error: couldn't load texture image\n");
exit(1);
}
glShadeModel(GL_FLAT);
glClearColor(0.3, 0.3, 0.4, 1.0);
ModeMenu(TEXBOTH);
}
int main( int argc, char *argv[] )
{
glutInit( &argc, argv );
glutInitWindowSize( 300, 300 );
glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
glutCreateWindow(argv[0] );
Init();
glutReshapeFunc( Reshape );
glutKeyboardFunc( Key );
glutSpecialFunc( SpecialKey );
glutDisplayFunc( Display );
glutIdleFunc( Idle );
glutCreateMenu(ModeMenu);
glutAddMenuEntry("Texture 0", TEX0);
glutAddMenuEntry("Texture 1", TEX1);
glutAddMenuEntry("Multi-texture", TEXBOTH);
glutAddMenuEntry("Toggle Animation", ANIMATE);
glutAddMenuEntry("Quit", QUIT);
glutAttachMenu(GLUT_RIGHT_BUTTON);
glutMainLoop();
return 0;
}
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