Adding texture to elements with openGL - c++

Question

I'm trying to build a giraffe with openGL. I already made the body and the walking, but I want to add texture I found. I'm adding my code for you to see.
#define _CRT_SECURE_NO_DEPRECATE
#include <stdlib.h>
#include <glut.h>
#include <stdio.h>
#include <math.h>
#include <windows.h>
#include <iostream>
#include <conio.h>
GLUquadricObj *p; /* pointer to quadric object */
GLuint GIRAFFE;
GLuint BODY;
GLuint LEGUP;
GLuint LEGDOWN;
GLuint HEAD;
GLuint CORN;
GLuint EYES;
GLuint TAIL;
GLuint LIST_NAME;
GLuint BODY_PAINT;
float MAX=10.0, MIN=-10.0;
int flagLeft = 0, flagRight = 0; //flags that indicates if the giraffe can move to the left or the right. if 0 - it can, if 1 - it can't
float XPlace=0.0,YPlace=0.0,ZPlace=0.0, rotation = 0.0; //indicators where the giraffe is at a current time
int position = 0; //index for setting the legs of the girrafe. 0 - all four legs standing. 1 - forward right and backwards left are in the air, forward left and backward right are on the ground. 2 - forward right and backwards left are on the ground, forward left and backward right are in the air
GLuint LoadTexture(char *filename) // load a textures //
{
GLuint texture;
BITMAPFILEHEADER fileheader;
BITMAPINFOHEADER infoheader;
RGBTRIPLE pixel;
FILE *pFile = fopen( filename, "rb"); // Open the file for reading to buffer
if( pFile == NULL) return (-1);
fread( &fileheader, sizeof(fileheader), 1, pFile); // Read the file_header
fread( &infoheader, sizeof(infoheader), 1, pFile); // and read the info_header
//----------------
int w,h, nSize;
w=(int)(infoheader.biWidth);
h=(int)(infoheader.biHeight);
nSize = w * h * 4; //in memory: 4 bytes for every readed pixel
// Allocation memory for our image (width * height * bytesPerPixel)
unsigned char *pImage = (unsigned char *)new char[nSize];
//------------
// Read w*h times data about every pixel from BMP file and locate them to memory
// if our file is 24-bit Bitmap type, so for every pixel we have 24/8=3 Bytes
// in this program size of memory for Image bigger of size of file
// (in memory: 4 bytes for every pixel)
int j = 0; //index for Image
for( int i=0; i < w * h; i ++ ) //index for BMP file
{
// We load an RGB value from the file
fread( &pixel, sizeof(pixel), 1, pFile);
// And store data in right places( additional here every rgb pixel = 4 bytes)
pImage[j+0] = pixel.rgbtRed; // Red component
pImage[j+1] = pixel.rgbtGreen; // Green component
pImage[j+2] = pixel.rgbtBlue; // Blue component
pImage[j+3] = 255; // Alpha value - is used in the process
//of combining texture with background
//to create a partial transparency
j += 4; // Go to the next 4 bytes in memory
}
fclose( pFile ); // Close the file stream
glEnable(GL_TEXTURE_2D);
glGenTextures( 1, &texture );
glBindTexture(GL_TEXTURE_2D, texture);
glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST );
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
// the texture wraps over at the edges (repeat)
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT );
glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT );
// Make Texture(2D MIPmaps format image) from our Image in memory
//in this program for texture we define 4 bytes for 1 pixel
gluBuild2DMipmaps(GL_TEXTURE_2D, 4, w, h, GL_RGBA, GL_UNSIGNED_BYTE, pImage);
free(pImage);
return texture;
}
#pragma region Body Parts
void HoofDown() //the hoof of the giraffe when it's down
{
glPushMatrix();
glTranslatef(-3,-7.5,1.8);
glColor3f(0.4, 0.75, 0.13);
glRotatef(245.0, 0.2, 0.2, 0.2);
gluDisk(p, 0.,1.,25,5);
glPopMatrix();
}
void HoofUp() //the hoof of the giraffe when it's up
{
glPushMatrix();
glTranslatef(-7,-6,1.8);
glColor3f(0.4, 0.75, 0.13);
glRotatef(220.0, 0.2, 0.2, 0.2);
gluDisk(p, 0.,1.,25,5);
glPopMatrix();
}
void Chest() //CHEST
{
glPushMatrix();
glTranslatef(-2,2.,0.);
glRotatef(90,1.,1.,0.);
gluCylinder(p,2.5,1.5,4.5,15,10);
glPopMatrix();
}
void Neck()
{
glPushMatrix();
glTranslatef(-5,14,0);
glRotatef(90,1,0.2,0);
gluCylinder(p,0.5,1.3,11,15,10);
glPopMatrix();
}
void ThighDown() //the thigh of the giraffe when it's down
{
glPushMatrix();
glTranslatef(-3,0.5,1.5);
glColor3f(0.4, 0.75, 0.13);
glRotatef(90,1.,0.,0.);
gluCylinder(p,0.5,0.5,4,15,10);
glPopMatrix();
}
void ThighUp() //the thigh of the giraffe when it's up
{
glPushMatrix();
glTranslatef(-3,0.5,1.5);
glColor3f(0.4, 0.75, 0.13);
glRotatef(90,3.,-3.,0.);
gluCylinder(p,0.5,0.5,4,15,10);
glPopMatrix();
}
void LegDown() //the leg of the giraffe when it's down
{
glPushMatrix();
glTranslatef(-3,-3.5,1.5);
glColor3f(0.4, 0.75, 0.13);
glRotatef(90,0.5,0.,0.);
gluCylinder(p,0.5,0.5,4,15,10);
glPopMatrix();
}
void LegUp() //the leg of the giraffe when it's up
{
glPushMatrix();
glTranslatef(-5.7,-2.2,1.5);
glColor3f(0.4, 0.75, 0.13);
glRotatef(90,1.5,-0.5,0.);
gluCylinder(p,0.5,0.5,4,15,10);
glPopMatrix();
}
void FootDown() //the lower leg of the giraffe when it's down
{
glPushMatrix();
glTranslatef(-3,-3.5,1.5);
glColor3f(0.4, 0.75, 0.13);
glRotatef(86,1.,0.,0.);
gluCylinder(p,0.3,0.7,4,15,10);
glPopMatrix();
}
void FootUp() //the lower leg of the giraffe when it's up
{
glPushMatrix();
glTranslatef(-5.7,-2.2,1.5);
glColor3f(0.4, 0.75, 0.13);
glRotatef(90,1.5,-0.5,0.);
gluCylinder(p,0.3,0.7,4,15,10);
glPopMatrix();
}
void Head1() //head part1
{
glPushMatrix();
glTranslatef(-5.3,14.3,0);
glRotatef(90,1.,-0.9,0.);
gluCylinder(p,0.7,0.3,3,15,10);
glPopMatrix();
}
void Cornp1() //corn part1
{
glPushMatrix();
glTranslatef(-8.8,14.3,0);
glColor3f(0.5, 0.35, 0.05);
glRotatef(90,1.,0.3,0.);
gluCylinder(p,0,0.2,1,15,10);
glPopMatrix();
}
void Cornp2() //corn part2
{
glPushMatrix();
glTranslatef(-8.6,13.3,0);
glRotatef(90,1.,0.9,0.);
gluCylinder(p,0.2,0.4,1,15,10);
glPopMatrix();
}
void Sphere()
{
glPushMatrix();
glTranslatef(-1.92,2,0.);
glRotatef(0.,0.,0.,1.);
gluSphere(p,2.5,15,21);
glPopMatrix();
}
void Sphere2()
{
glPushMatrix();
glTranslatef(1.5,-1.5,0.);
gluSphere(p,1.5,15,21);
glPopMatrix();
}
void Headp2() //head part2
{
glPushMatrix();
glTranslatef(-5.2,14.5,0.);
gluSphere(p,0.8,15,21);
glPopMatrix();
}
void Headp3() //head part3
{
glPushMatrix();
glTranslatef(-7.4,11.8,0.);
gluSphere(p,0.5,15,21);
glPopMatrix();
}
void HeadMiddle() //head middle part4
{
glPushMatrix();
glTranslatef(-6,12.8,0.);
gluSphere(p,0.5,15,21);
glPopMatrix();
}
void Eyes() //EYES
{
glPushMatrix();
glTranslatef(-11,12.9,0.2);
glColor3f(0.4, 0.75, 0.13);
gluSphere(p,0.2,15,21);
glPopMatrix();
}
void Tail()
{
glPushMatrix();
glTranslatef(-2.4,-0.3,-0.5);
glRotatef(90,1,0.5,0);
gluCylinder(p,0.2,0.1,4,15,10);
glPopMatrix();
}
#pragma endregion
#pragma region Leg Positions
void stand() //all four legs of the giraffe are on the ground
{
glCallList (LEGDOWN); //leg forward right
glPopMatrix();
glTranslatef (0, 0,-2.5);
glCallList (LEGDOWN); //leg forward left
glPopMatrix();
glScalef(1,1,1);
glTranslatef (5.4, -1.6, 0.3);
glScalef(1,0.8,1);
glCallList (LEGDOWN); //leg backward left
glPopMatrix();
glTranslatef (0, 0 ,1.5);
glCallList (LEGDOWN); //leg backward right
glPopMatrix();
}
void rightUp() //forward right and backwards left are in the air, forward left and backward right are on the ground
{
glCallList (LEGUP); //leg forward right
glPopMatrix();
glTranslatef (0, 0,-2.5);
glCallList (LEGDOWN); //leg forward left
glPopMatrix();
glScalef(1,1,1);
glTranslatef (5.4, -1.6, 0.3);
glScalef(1,0.8,1);
glCallList (LEGUP); //leg backward left
glPopMatrix();
glTranslatef (0, 0 ,1.5);
glCallList (LEGDOWN); //leg backward right
glPopMatrix();
}
void leftUp() //forward right and backwards left are on the ground, forward left and backward right are in the air
{
glCallList (LEGDOWN); //leg forward right
glPopMatrix();
glTranslatef (0, 0,-2.5);
glCallList (LEGUP); //leg forward left
glPopMatrix();
glScalef(1,1,1);
glTranslatef (5.4, -1.6, 0.3);
glScalef(1,0.8,1);
glCallList (LEGDOWN); //leg backward left
glPopMatrix();
glTranslatef (0, 0 ,1.5);
glCallList (LEGUP); //leg backward right
glPopMatrix();
}
#pragma endregion
void display(void)
{
glClear(GL_COLOR_BUFFER_BIT);
glLoadIdentity();
glRotatef(0+rotation,0.,2.,0.);
glTranslatef(XPlace,YPlace,ZPlace);
glCallList (BODY);
glCallList (HEAD);
glTranslatef (2, 2, 0.6);
glCallList (CORN);
glTranslatef (0, 0, -0.7);
glCallList (CORN);
glTranslatef (-2.3, -1.3, 0);
glScalef(1,1.5,1);
switch (position)
{
case 0:
stand();
break;
case 1:
rightUp();
break;
default:
leftUp();
break;
}
glCallList (EYES);
glTranslatef (0, 0 ,1.2);
glCallList (EYES);
glCallList (TAIL);
glFlush();
glutSwapBuffers();
}
void rotate(int direction)
{
if(direction == 1)
rotation += 0.5;
if(direction == 2)
rotation -= 0.5;
}
void myReshape(int w,int h)
{
glViewport(0, 0, w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(-20.,20.,-20.,20.,-20.,20.);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
void changePosition() //changing the position for setting the legs
{
position++;
if(position == 3)
position = 0;
}
void myinit()
{
LIST_NAME= glGenLists (9);
BodyPaint = LoadTexture("giraffeSkin.bmp");
p=gluNewQuadric(); /* allocate quadric object */
gluQuadricDrawStyle(p, GLU_LINE); /* render it as wireframe */
glClearColor(1.0, 1.0, 1.0, 1.0);
glColor3f(0.4, 0.75, 0.13);
BODY=LIST_NAME;
glNewList (BODY, GL_COMPILE);
Chest();
Neck();
Sphere();
Sphere2();
glEndList();
LEGUP=LIST_NAME+1;
glNewList(LEGUP ,GL_COMPILE);
ThighUp();
LegUp();
FootUp();
HoofUp();
glEndList();
LEGDOWN=LIST_NAME+2;
glNewList(LEGDOWN ,GL_COMPILE);
ThighDown();
LegDown();
FootDown();
HoofDown();
glEndList();
HEAD=LIST_NAME+3;
glNewList(HEAD,GL_COMPILE);
Head1();
Headp2();
Headp3();
glEndList();
CORN=LIST_NAME+4;
glNewList(CORN,GL_COMPILE);
Cornp1();
Cornp2();
glEndList();
EYES=LIST_NAME+5;
glNewList(EYES,GL_COMPILE);
Eyes();
glEndList();
TAIL=LIST_NAME+6;
glNewList(TAIL,GL_COMPILE);
Tail();
glEndList();
GIRAFFE=LIST_NAME+7;
}
void keyboard(unsigned char key, int x, int y)
{
switch (key)
{
case '2'://up
rotate(1);
glutPostRedisplay();
break;
case '4'://left
if(flagLeft==0)
{
flagRight = 0;
XPlace=XPlace-0.05;
if(XPlace<=MIN)
flagLeft=1;
changePosition();
}
glutPostRedisplay();
break;
case '6'://right
if(flagRight==0)
{
flagLeft = 0;
XPlace=XPlace+0.05;
if(XPlace>=MAX)
flagRight=1;
changePosition();
}
glutPostRedisplay();
break;
case '8'://down
rotate(2);
glutPostRedisplay();
break;
case 27: // ESC: exit the program
exit(0); break;
default:
break;
}
}
void main(int argc, char **argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
glutInitWindowSize(1000, 1000);
glutCreateWindow("Quadric Objects");
myinit();
glutKeyboardFunc(keyboard); // Register handler for key event
glutReshapeFunc(myReshape);
glutDisplayFunc(display);
glutMainLoop();
}
The texture I found named giraffeSkin.bmp
I know I should use glBindTexture function but I don't know where. Could someone give me a hand here?

Answer 1

It looks like you're using the quadrics ( for example, "gluCylinder" ) libraries. They have their own way of doing texture mappings. Look at the function gluQuadricTexture. You'll see that mapping on quadrics is a bit involved.
http://www.opengl.org/sdk/docs/man2/xhtml/gluQuadricTexture.xml
Meanwhile, when texture mapping, remember to call glEnable( GL_TEXTURE_2D )