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/*
* Test multitexture and paletted textures.
*/
#include <assert.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stddef.h> /* for ptrdiff_t, referenced by GL.h when GL_GLEXT_LEGACY defined */
#ifdef _WIN32
#include <windows.h>
#endif
#define GL_GLEXT_LEGACY
#include <GL/glut.h>
#include "../util/readtex.c" /* I know, this is a hack. */
#define TEXTURE_1_FILE "../images/tile.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;
if (Drift >= 1.0)
Drift = 0.0;
#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 load_tex(const char *fname, int channel)
{
GLubyte *image;
GLenum format;
GLint w, h;
GLubyte *grayImage;
int i;
GLubyte table[256][4];
image = LoadRGBImage(fname, &w, &h, &format);
if (!image)
exit(1);
printf("%s %d x %d\n", fname, w, h);
grayImage = malloc(w * h * 1);
assert(grayImage);
for (i = 0; i < w * h; i++) {
int g = (image[i*3+0] + image[i*3+1] + image[i*3+2]) / 3;
assert(g < 256);
grayImage[i] = g;
}
glTexImage2D(GL_TEXTURE_2D, 0, GL_COLOR_INDEX, w, h, 0, GL_COLOR_INDEX,
GL_UNSIGNED_BYTE, grayImage);
for (i = 0; i < 256; i++) {
table[i][0] = channel ? i : 0;
table[i][1] = i;
table[i][2] = channel ? 0 : i;
table[i][3] = 255;
}
glColorTableEXT(GL_TEXTURE_2D, /* target */
GL_RGBA, /* internal format */
256, /* table size */
GL_RGBA, /* table format */
GL_UNSIGNED_BYTE, /* table type */
table); /* the color table */
free(grayImage);
free(image);
}
static void Init( int argc, char *argv[] )
{
GLuint texObj[2];
GLint units;
if (!glutExtensionSupported("GL_ARB_multitexture")) {
printf("Sorry, GL_ARB_multitexture not supported by this renderer.\n");
exit(1);
}
if (!glutExtensionSupported("GL_EXT_paletted_texture")) {
printf("Sorry, GL_EXT_paletted_texture not supported by this renderer.\n");
exit(1);
}
glGetIntegerv(GL_MAX_TEXTURE_UNITS_ARB, &units);
printf("%d texture units supported\n", units);
/* allocate two texture objects */
glGenTextures(2, texObj);
/* setup texture obj 0 */
glBindTexture(GL_TEXTURE_2D, texObj[0]);
#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);
foo
#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);
load_tex(TEXTURE_1_FILE, 0);
#if 0
if (!LoadRGBMipmaps(TEXTURE_1_FILE, GL_RGB)) {
printf("Error: couldn't load texture image\n");
exit(1);
}
#endif
/* setup texture obj 1 */
glBindTexture(GL_TEXTURE_2D, texObj[1]);
#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);
foo
#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);
load_tex(TEXTURE_2_FILE, 1);
#if 0
if (!LoadRGBMipmaps(TEXTURE_2_FILE, GL_RGB)) {
printf("Error: couldn't load texture image\n");
exit(1);
}
#endif
/* now bind the texture objects to the respective texture units */
#ifdef GL_ARB_multitexture
glActiveTextureARB(GL_TEXTURE0_ARB);
glBindTexture(GL_TEXTURE_2D, texObj[0]);
glActiveTextureARB(GL_TEXTURE1_ARB);
glBindTexture(GL_TEXTURE_2D, texObj[1]);
#endif
glShadeModel(GL_FLAT);
glClearColor(0.3, 0.3, 0.4, 1.0);
ModeMenu(TEXBOTH);
if (argc > 1 && strcmp(argv[1], "-info")==0) {
printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
printf("GL_VERSION = %s\n", (char *) glGetString(GL_VERSION));
printf("GL_VENDOR = %s\n", (char *) glGetString(GL_VENDOR));
printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
}
}
int main( int argc, char *argv[] )
{
glutInit( &argc, argv );
glutInitWindowSize( 300, 300 );
glutInitWindowPosition( 0, 0 );
glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
glutCreateWindow(argv[0] );
Init( argc, argv );
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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