texture.c

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    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();
}

void
world_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();
}

void
screen_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);
}

void
screen_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;

void
screen_mouse(int button, int state, int x, int y)
{
    old_x = x;
    old_y = y;
    
    redisplay_all();
}

void
screen_motion(int x, int y)
{
    spin_x = x - old_x;
    spin_y = y - old_y;
    
    redisplay_all();
}

void
command_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);
}

void
polygon_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);
}

void
matrix_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();
}

void
parameters_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, ");");