Hi, I was wondering if anyone knows of a good easy tutorial on enabling hidden surface removal in a program. Thanks Marc

I tried that but it didn't work. Here is all my code (prior to trying that):

#include <windows.h>
#include <stdlib.h>
#include <gl\gl.h>
#include <fstream>
#include <iostream>
#include <list>
#include <gl\glut.h>
#include <gl\glu.h> /* GLU extention library */

#define EXIT 1
#define RESET 2

using namespace std;

GLfloat worldx = 0;
GLfloat worldy = 0;
GLfloat worldxBegin = 0;
GLfloat worldyBegin = 0;
GLfloat worldxEnd = 0;
GLfloat worldyEnd = 0;
GLfloat wc1 = 0.5;
GLfloat wc2 = 0.5;
GLfloat wc3 = 0.5;

//Global movement variables
GLfloat moveY = 0;
GLfloat moveZ = 0;
GLfloat rotateArrow = 0;
GLfloat arrowPosX = 0;
GLfloat arrowPosY = 0;



list<char> commandList; //List that stores command operations from file
list<GLfloat> dataList; //List that stores transformations/scalings/color changes of objects

void init(void);
void display(void);
void keyboard(unsigned char, int, int);
void resize(int, int);
void drawObjects();
void readFile(string);
void createDisplayLists(void);
void createMenu(void);
void processMenuEvents(int);
void myTimer(int);
void reset(void);
void displayMap(void);
void specialKeyboard(int key, int x, int y);

int is_depth; /* depth testing flag */
GLint window3D,windowMap;



int main (int argc, char **argv)
{
glutInit(&argc, argv);
init();
string filename = "su08_world2.dat";
readFile(filename);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);

glutInitWindowSize(600, 600);
glutInitWindowPosition(1,1);

//Create First 3D world window
window3D = glutCreateWindow("jkjk");
createDisplayLists();
glutCreateMenu(processMenuEvents);
glutAddMenuEntry("Exit",EXIT);
glutAddMenuEntry("Reset",RESET);
glutAttachMenu(GLUT_RIGHT_BUTTON);
int n = 30;
glutTimerFunc(100,myTimer,n);
glutSpecialFunc(specialKeyboard);
glutReshapeFunc(resize);
glutDisplayFunc(display);
glutIdleFunc(display);
//Set initial position
glTranslatef(0.0, -4.0, 0.0);

glutMainLoop();
return 0;

}

void init(void)
{
glEnable(GL_DEPTH_TEST);
is_depth = 1;
glMatrixMode(GL_MODELVIEW);
}

//Function that creates 3D world
void display(void)
{
glutSetWindow(window3D);
glTranslatef(0.0, moveY, moveZ);

glClearColor(0, 0, 1, 0.0);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);



/* draw 3D world */
glPushAttrib(GL_ALL_ATTRIB_BITS);
glPushMatrix();

gluLookAt(0,0,0,worldxBegin-200,worldyBegin-200,1,1,1,1);
/* draw the floor */
glPushAttrib(GL_ALL_ATTRIB_BITS);
glPushMatrix();
glRotatef(90,1,0,0);
glScalef(worldx+10,1,worldy+10);
glBegin(GL_QUADS);
glColor3f(wc1, wc2, wc3);
glVertex3f( 0.5f,-0.5f, 0.5f); // Top Right Of The Quad (Bottom)
glVertex3f(-0.5f,-0.5f, 0.5f); // Top Left Of The Quad (Bottom)
glVertex3f(-0.5f,-0.5f,-0.5f); // Bottom Left Of The Quad (Bottom)
glVertex3f( 0.5f,-0.5f,-0.5f); // Bottom Right Of The Quad (Bottom)
glEnd();
glPopAttrib();
glPopMatrix();


drawObjects();
glPopAttrib();
glPopMatrix();
glutSwapBuffers();

}



void resize(int width, int height)
{
if (height == 0) height = 1;
glMatrixMode(GL_PROJECTION);
glLoadIdentity();

gluPerspective(45.0, width / height, 1.0, 400.0);

/* set initial position */
glTranslatef(0.0, -4.0, 0.0);
glMatrixMode(GL_MODELVIEW);

}

void drawObjects()
{
list<GLfloat>::iterator di=dataList.begin();

for(list<char>::iterator ai=commandList.begin(); ai!=commandList.end(); ++ai)
{
GLfloat x,y,z;
switch (*ai)
{
case 'c' :
x = *di;
di++;
y = *di;
di++;
z = *di;
di++;
glColor3f(x,y,z);
break;


case 'b' :
x = *di;
di++;
y = *di;
di++;
z = *di;
di++;
glPushAttrib(GL_ALL_ATTRIB_BITS);
glPushMatrix();
glTranslatef(x,y,z);
x = *di;
di++;
y = *di;
di++;
z = *di;
di++;
glScalef(x,y,z);
glCallList(2);
glPopAttrib();
glPopMatrix();
break;

case 's' :
x = *di;
di++;
y = *di;
di++;
z = *di;
di++;
glPushAttrib(GL_ALL_ATTRIB_BITS);
glPushMatrix();
glTranslatef(x,y,z);
z = *di;
di++;
glScalef(1.0,1.0,z);
glCallList(3);
glPopAttrib();
glPopMatrix();
break;

case 'a' :
//ignore advance 3
di++;
di++;
di++;
break;

case 'l' :
//ignore advance 6
di++;
di++;
di++;
di++;
di++;
di++;
break;
}//switch
}//for
}//void



//Function that creates Display lists of a block and a sphere
void createDisplayLists()
{
//Block defined with 6 polygons
glNewList(2, GL_COMPILE);
glBegin(GL_QUADS);
glVertex3f( 0.5f, 0.5f,-0.5f); // Top Right Of The Quad (Top)
glVertex3f(-0.5f, 0.5f,-0.5f); // Top Left Of The Quad (Top)
glVertex3f(-0.5f, 0.5f, 0.5f); // Bottom Left Of The Quad (Top)
glVertex3f( 0.5f, 0.5f, 0.5f); // Bottom Right Of The Quad (Top)

glVertex3f( 0.5f,-0.5f, 0.5f); // Top Right Of The Quad (Bottom)
glVertex3f(-0.5f,-0.5f, 0.5f); // Top Left Of The Quad (Bottom)
glVertex3f(-0.5f,-0.5f,-0.5f); // Bottom Left Of The Quad (Bottom)
glVertex3f( 0.5f,-0.5f,-0.5f); // Bottom Right Of The Quad (Bottom)

glVertex3f( 0.5f, 0.5f, 0.5f); // Top Right Of The Quad (Front)
glVertex3f(-0.5f, 0.5f, 0.5f); // Top Left Of The Quad (Front)
glVertex3f(-0.5f,-0.5f, 0.5f); // Bottom Left Of The Quad (Front)
glVertex3f( 0.5f,-0.5f, 0.5f); // Bottom Right Of The Quad (Front)

glVertex3f( 0.5f,-0.5f,-0.5f); // Bottom Left Of The Quad (Back)
glVertex3f(-0.5f,-0.5f,-0.5f); // Bottom Right Of The Quad (Back)
glVertex3f(-0.5f, 0.5f,-0.5f); // Top Right Of The Quad (Back)
glVertex3f( 0.5f, 0.5f,-0.5f); // Top Left Of The Quad (Back)

glVertex3f(-0.5f, 0.5f, 0.5f); // Top Right Of The Quad (Left)
glVertex3f(-0.5f, 0.5f,-0.5f); // Top Left Of The Quad (Left)
glVertex3f(-0.5f,-0.5f,-0.5f); // Bottom Left Of The Quad (Left)
glVertex3f(-0.5f,-0.5f, 0.5f); // Bottom Right Of The Quad (Left)

glVertex3f( 0.5f, 0.5f,-0.5f); // Top Right Of The Quad (Right)
glVertex3f( 0.5f, 0.5f, 0.5f); // Top Left Of The Quad (Right)
glVertex3f( 0.5f,-0.5f, 0.5f); // Bottom Left Of The Quad (Right)
glVertex3f( 0.5f,-0.5f,-0.5f); // Bottom Right Of The Quad (Right)
glEnd(); // Done Drawing The Quad

glEnd();
glEndList();

//Unit sphere centered at origin
glNewList(3, GL_COMPILE);
GLUquadricObj *p;
p = gluNewQuadric();
gluSphere(p,1,100,100);
glEndList();
}


void myTimer(int v)
{
glutPostRedisplay();
glutTimerFunc(1000/v,myTimer,v);
}

I tried it and it kind of works. SOme of my objects are drawn correctly but others still show up as if hidden surface removal is not enabled.

Thanks

Quote:Original post by mbanghart
I tried it and it kind of works. SOme of my objects are drawn correctly but others still show up as if hidden surface removal is not enabled.

Thanks

If the surface are hidden, why would it "show up"?

It is not that hard to write a description that is logically correct. If it is going to take up a huge paragraph to describe, show us an image instead. Posting a long long not compile-able source code, while hoping for someone can guess what is in your mind, is a very bad option.

How do I attach an image to this post?

Good Example: Grey shapes in front of green ones display correctly.

Incorrect Ex: Behind the white rectangle there is a yellow object and some green objects. The green objects should appear in front of the yellow one.

Thanks

Use ordinary HTML img tags. If you need a place to upload the image use http://www.imageshack.us/.

int main (int argc, char **argv)
{
//...
window3D = glutCreateWindow("jkjk");

// In order for this command to be delivered,
// it should be called after a window was created.
glEnable(GL_DEPTH_TEST);

createDisplayLists();
//...

Quote:Original post by mbanghart
...
Good Example: Grey shapes in front of green ones display correctly.
Incorrect Ex: Behind the white rectangle there is a yellow object and some green objects. The green objects should appear in front of the yellow one.
...

By the way, do you really think there is someone can understand what you wrote by reading? If so, can you?