glVertex2i(twidth, theight);    glTexCoord2f(-0.5, 1.5);    glVertex2i(0, theight);    glEnd();        glBegin(GL_POLYGON);    glTexCoord2f(-0.5, -0.5);    glVertex2i(-1, -1);    glTexCoord2f(1.5, -0.5);    glVertex2i(1, -1);    glTexCoord2f(1.5, 1.5);    glVertex2i(1, 1);    glTexCoord2f(-0.5, 1.5);    glVertex2i(-1, 1);    glEnd();        glDisable(GL_TEXTURE_2D);    glDisable(GL_LIGHTING);        glScalef(twidth/2, theight/2, 1.0);    glTranslatef(0.5, 0.5, 0.0);    glTranslatef(translation[0].value, translation[1].value,        translation[2].value);    glRotatef(rotation[0].value, rotation[1].value,         rotation[2].value, rotation[3].value);    glScalef(scale[0].value, scale[1].value, scale[2].value);        /* axes */    glPushMatrix();    glTranslatef(-0.001, -0.001, 0.0);    glColor3ub(0, 255, 128);    glBegin(GL_LINE_STRIP);    glVertex2f(0.1, 0.5);    glVertex2f(0.0, 0.6);    glVertex2f(-0.1, 0.5);    glEnd();    glBegin(GL_LINE_STRIP);    glVertex2f(0.5, 0.1);    glVertex2f(0.6, 0.0);    glVertex2f(0.5, -0.1);    glEnd();    glBegin(GL_LINE_STRIP);    glVertex2f(0.6, 0.0);    glVertex2f(0.0, 0.0);    glVertex2f(0.0, 0.6);    glEnd();    glColor3ub(255, 255, 0);    glRasterPos2f(0.6, -0.1);    glutBitmapCharacter(GLUT_BITMAP_HELVETICA_12, 's');    glRasterPos2f(-0.1, 0.6);    glutBitmapCharacter(GLUT_BITMAP_HELVETICA_12, 't');    glPopMatrix();        glEnable(GL_LINE_STIPPLE);    glLineStipple(1, (GLushort)stipple);    glColor3ub(255, 0, 0);    glBegin(GL_LINE_LOOP);    glVertex2f(texcoords[0].value, texcoords[1].value);    glVertex2f(texcoords[2].value, texcoords[3].value);    glVertex2f(texcoords[4].value, texcoords[5].value);    glVertex2f(texcoords[6].value, texcoords[7].value);    glEnd();    glLineStipple(1, (GLushort)(stipple^0xffff));    glColor3ub(255, 255, 255);    glBegin(GL_LINE_LOOP);    glVertex2f(texcoords[0].value, texcoords[1].value);    glVertex2f(texcoords[2].value, texcoords[3].value);    glVertex2f(texcoords[4].value, texcoords[5].value);    glVertex2f(texcoords[6].value, texcoords[7].value);    glEnd();    glDisable(GL_LINE_STIPPLE);        glutSwapBuffers();}voidworld_menu(int value){    char* name = 0;        switch (value) {    case 'f':        name = "data/fishermen.ppm";        break;    case 'o':        name = "data/opengl.ppm";        break;    case 'c':        name = "data/checker.ppm";        break;    case 'm':        name = "data/marble.ppm";        break;    case 't':        name = "data/train.ppm";        break;    }        if (name) {        free(image);        image = glmReadPPM(name, &iwidth, &iheight);        if (!image)
            image = glmReadPPM("data/fishermen.ppm", &iwidth, &iheight);    }        glutSetWindow(screen);    texture();    glutSetWindow(world);    texture();        redisplay_all();}voidscreen_reshape(int width, int height){    glViewport(0, 0, width, height);    glMatrixMode(GL_PROJECTION);    glLoadIdentity();    gluPerspective(60.0, (GLfloat)width/height, 0.5, 8.0);    glMatrixMode(GL_MODELVIEW);    glLoadIdentity();    gluLookAt(eye[0], eye[1], eye[2], at[0], at[1], at[2], up[0], up[1],up[2]);    glClearColor(0.2, 0.2, 0.2, 1.0);    glEnable(GL_COLOR_MATERIAL);    glEnable(GL_DEPTH_TEST);    glEnable(GL_LIGHTING);    glEnable(GL_LIGHT0);    glEnable(GL_TEXTURE_2D);    glMatrixMode(GL_TEXTURE);    glLoadIdentity();    glTranslatef(translation[0].value, translation[1].value,        translation[2].value);    glRotatef(rotation[0].value, rotation[1].value,         rotation[2].value, rotation[3].value);    glScalef(scale[0].value, scale[1].value, scale[2].value);    glMatrixMode(GL_MODELVIEW);}voidscreen_display(void){    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);        glPushMatrix();    glRotatef(spin_y, 1.0, 0.0, 0.0);    glRotatef(spin_x, 0.0, 1.0, 0.0);        glColor4f(pcolor[0].value, pcolor[1].value, pcolor[2].value, pcolor[3].value);    glBegin(GL_POLYGON);    glNormal3f(0.0, 0.0, 1.0);    glTexCoord2f(texcoords[0].value, texcoords[1].value);    glVertex3f(vertices[0].value, vertices[1].value, vertices[2].value);    glTexCoord2f(texcoords[2].value, texcoords[3].value);    glVertex3f(vertices[3].value, vertices[4].value, vertices[5].value);    glTexCoord2f(texcoords[4].value, texcoords[5].value);    glVertex3f(vertices[6].value, vertices[7].value, vertices[8].value);    glTexCoord2f(texcoords[6].value, texcoords[7].value);    glVertex3f(vertices[9].value, vertices[10].value, vertices[11].value);    glEnd();        glPopMatrix();    glutSwapBuffers();}int old_x, old_y;voidscreen_mouse(int button, int state, int x, int y){    old_x = x;    old_y = y;        redisplay_all();}voidscreen_motion(int x, int y){    spin_x = x - old_x;    spin_y = y - old_y;        redisplay_all();}voidcommand_reshape(int width, int height){    glViewport(0, 0, width, height);    glMatrixMode(GL_PROJECTION);    glLoadIdentity();    gluOrtho2D(0, width, height, 0);    glMatrixMode(GL_MODELVIEW);    glLoadIdentity();    glClearColor(0.0, 0.0, 0.0, 0.0);    glDisable(GL_DEPTH_TEST);}voidpolygon_display(void){    setfont("helvetica", 12);        drawstr(10, pcolor[0].y-50, "glEnable(GL_TEXTURE_2D);");    drawstr(10, pcolor[0].y-30, "gluBuild2DMipmaps(GL_TEXTURE_2D, 3, w, h, "        "GL_RGB, GL_UNSIGNED_BYTE, image);");        setfont("helvetica", 18);        drawstr(10, pcolor[0].y, "glColor4f(");    drawstr(pcolor[0].x+50, pcolor[0].y, ",");    drawstr(pcolor[1].x+50, pcolor[1].y, ",");     drawstr(pcolor[2].x+50, pcolor[2].y, ",");     drawstr(pcolor[3].x+50, pcolor[2].y, ");");         drawstr(10, texcoords[0].y-30, "glBegin(GL_POLYGON);");    drawstr(10, texcoords[0].y, "glTexCoord2f(");    drawstr(texcoords[0].x+40, texcoords[0].y, ",");    drawstr(texcoords[1].x+40, texcoords[1].y, ");");     drawstr(250, vertices[0].y, "glVertex3f(");    drawstr(vertices[0].x+40, vertices[0].y, ",");    drawstr(vertices[1].x+40, vertices[1].y, ",");     drawstr(vertices[2].x+40, vertices[1].y, ");");         drawstr(10, texcoords[2].y, "glTexCoord2f(");    drawstr(texcoords[2].x+40, texcoords[2].y, ",");    drawstr(texcoords[3].x+40, texcoords[3].y, ");");     drawstr(250, vertices[3].y, "glVertex3f(");    drawstr(vertices[3].x+40, vertices[3].y, ",");    drawstr(vertices[4].x+40, vertices[4].y, ",");     drawstr(vertices[5].x+40, vertices[5].y, ");");         drawstr(10, texcoords[4].y, "glTexCoord2f(");    drawstr(texcoords[4].x+40, texcoords[4].y, ",");    drawstr(texcoords[5].x+40, texcoords[5].y, ");");     drawstr(250, vertices[6].y, "glVertex3f(");    drawstr(vertices[6].x+40, vertices[6].y, ",");    drawstr(vertices[7].x+40, vertices[7].y, ",");     drawstr(vertices[8].x+40, vertices[8].y, ");");         drawstr(10, texcoords[6].y, "glTexCoord2f(");    drawstr(texcoords[6].x+40, texcoords[6].y, ",");    drawstr(texcoords[7].x+40, texcoords[7].y, ");");     drawstr(250, vertices[9].y, "glVertex3f(");    drawstr(vertices[9].x+40, vertices[9].y, ",");    drawstr(vertices[10].x+40, vertices[10].y, ",");     drawstr(vertices[11].x+40, vertices[11].y, ");");         drawstr(10, vertices[11].y+30, "glEnd();");        cell_draw(&texcoords[0]);     cell_draw(&texcoords[1]);     cell_draw(&texcoords[2]);     cell_draw(&texcoords[3]);     cell_draw(&texcoords[4]);     cell_draw(&texcoords[5]);     cell_draw(&texcoords[6]);     cell_draw(&texcoords[7]);         cell_draw(&vertices[0]);    cell_draw(&vertices[1]);    cell_draw(&vertices[2]);    cell_draw(&vertices[3]);    cell_draw(&vertices[4]);    cell_draw(&vertices[5]);    cell_draw(&vertices[6]);    cell_draw(&vertices[7]);    cell_draw(&vertices[8]);    cell_draw(&vertices[9]);    cell_draw(&vertices[10]);    cell_draw(&vertices[11]);        cell_draw(&pcolor[0]);    cell_draw(&pcolor[1]);    cell_draw(&pcolor[2]);    cell_draw(&pcolor[3]);        glColor3ub(255, 255, 255);}voidmatrix_display(void){    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);        glColor3ub(255, 255, 255);        polygon_display();        setfont("helvetica", 18);        drawstr(10, translation[0].y-30, "glMatrixMode(GL_TEXTURE);");    drawstr(10, translation[0].y, "glTranslatef(");    drawstr(170, translation[0].y, ",");    drawstr(230, translation[0].y, ",");     drawstr(290, translation[0].y, ");");    drawstr(30, rotation[0].y, "glRotatef(");    drawstr(170, rotation[0].y, ",");    drawstr(230, rotation[0].y, ",");     drawstr(290, rotation[0].y, ",");    drawstr(350, rotation[0].y, ");");    drawstr(38, scale[0].y, "glScalef(");    drawstr(170, scale[0].y, ",");    drawstr(230, scale[0].y, ",");     drawstr(290, scale[0].y, ");");    drawstr(10, scale[0].y+30, "glMatrixMode(GL_MODELVIEW);");        cell_draw(&translation[0]);    cell_draw(&translation[1]);    cell_draw(&translation[2]);        cell_draw(&rotation[0]);    cell_draw(&rotation[1]);    cell_draw(&rotation[2]);    cell_draw(&rotation[3]);        cell_draw(&scale[0]);    cell_draw(&scale[1]);    cell_draw(&scale[2]);        if (!selection) {        glColor3ub(255, 255, 0);        drawstr(10, 525,            "Click on the arguments and move the mouse to modify values.");    }           glutSwapBuffers();}voidparameters_display(void){    float pos[4];        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);        glColor3ub(255, 255, 255);        polygon_display();        setfont("helvetica", 18);    drawstr(10, bcolor[0].y, "GLfloat border_color[ ] = { ");    drawstr(bcolor[0].x+40, bcolor[0].y, ",");    drawstr(bcolor[1].x+40, bcolor[0].y, ",");    drawstr(bcolor[2].x+40, bcolor[0].y, ",");    drawstr(bcolor[3].x+40, bcolor[0].y, "};");    drawstr(10, ecolor[0].y, "GLfloat env_color[ ] = { ");    drawstr(ecolor[0].x+40, ecolor[0].y, ",");    drawstr(ecolor[1].x+40, ecolor[0].y, ",");    drawstr(ecolor[2].x+40, ecolor[0].y, ",");    drawstr(ecolor[3].x+40, ecolor[0].y, "};");        setfont("helvetica", 12);    drawstr(10, 90, "glTexParameterfv(GL_TEXTURE_2D, GL_TEXTURE_BORDER_COLOR,"        " border_color);");    drawstr(10, 110, "glTexEnvfv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, "        "env_color);");        drawstr(10, 140, "glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,");    drawstr(10, 160, "glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER,");    drawstr(10, 180, "glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S,");    drawstr(10, 200, "glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T,");    drawstr(10, 220, "glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE,");        glColor3ub(0, 255, 128);    if (minfilter == GL_LINEAR_MIPMAP_LINEAR) {        drawstr(380, 140, "GL_LINEAR_MIPMAP_LINEAR");    } else if (minfilter == GL_LINEAR_MIPMAP_NEAREST) {        drawstr(380, 140, "GL_LINEAR_MIPMAP_NEAREST");    } else if (minfilter == GL_NEAREST_MIPMAP_LINEAR) {        drawstr(380, 140, "GL_NEAREST_MIPMAP_LINEAR");    } else if (minfilter == GL_NEAREST_MIPMAP_NEAREST) {        drawstr(380, 140, "GL_NEAREST_MIPMAP_NEAREST");    } else if (minfilter == GL_LINEAR) {        drawstr(380, 140, "GL_LINEAR");    } else {        drawstr(380, 140, "GL_NEAREST");    }        glColor3ub(255, 255, 255);    glGetFloatv(GL_CURRENT_RASTER_POSITION, pos);     drawstr(pos[0]+2, glutGet(GLUT_WINDOW_HEIGHT)-pos[1]-1, ");");    glColor3ub(0, 255, 128);        if (magfilter == GL_LINEAR) {        drawstr(390, 160, "GL_LINEAR");    } else {        drawstr(390, 160, "GL_NEAREST");    }        glColor3ub(255, 255, 255);    glGetFloatv(GL_CURRENT_RASTER_POSITION, pos);     drawstr(pos[0]+2, glutGet(GLUT_WINDOW_HEIGHT)-pos[1]-1, ");");    glColor3ub(0, 255, 128);        if (wraps == GL_REPEAT) {        drawstr(360, 180, "GL_REPEAT");    } else {        drawstr(360, 180, "GL_CLAMP");    }        glColor3ub(255, 255, 255);    glGetFloatv(GL_CURRENT_RASTER_POSITION, pos);     drawstr(pos[0]+2, glutGet(GLUT_WINDOW_HEIGHT)-pos[1]-1, ");");