draw two objects using openGL in a same time - c++

Question

I have several functions:
drawGrid() -> which draws a grid on the ground;
drawAxes() -> which is draw axes using the gluCylinder
Arrows() -> which is used in drawAxes to draw cones as arrows;
I cant understand why I can not call drawGrid and drawAxes in a same time; in this case the output is like this link:
http://www.4shared.com/photo/8YTsc17s/wrong.html
if I comment the drawGrid() I can see the axes fine; but I want to draw them simultaneously;
http://www.4shared.com/photo/KI3DER-5/Axis.html
this is the codes I used:
1. drawGrid
void Golsa::drawGrid(float size, float step)
{
// disable lighting
glDisable(GL_LIGHTING);
glBegin(GL_LINES);
glColor3f(0.3f, 0.3f, 0.3f);
for(float i=step; i <= size; i+= step)
{
glVertex3f(-size, 0, i); // lines parallel to X-axis
glVertex3f( size, 0, i);
glVertex3f(-size, 0, -i); // lines parallel to X-axis
glVertex3f( size, 0, -i);
glVertex3f( i, 0, -size); // lines parallel to Z-axis
glVertex3f( i, 0, size);
glVertex3f(-i, 0, -size); // lines parallel to Z-axis
glVertex3f(-i, 0, size);
}
}
2. drawAxes:
void Golsa:: drawAxes(double length)
{
glPushMatrix();
glTranslatef(-length,0,0);
Arrow(0,0,0, 2*length,0,0,0.2);
glPopMatrix();
glPushMatrix();
glTranslatef(0,-length,0);
Arrow(0,0,0, 0,2*length,0,0.2);
glPopMatrix();
glPushMatrix();
glTranslatef(0,0,-length);
Arrow(0,0,0, 0,0,2*length,0.2);
glPopMatrix();
}
3. Arrow
void Golsa::Arrow(GLdouble x1,GLdouble y1,GLdouble z1,GLdouble x2,GLdouble y2,GLdouble z2,GLdouble D)
{
double x=x2-x1;
double y=y2-y1;
double z=z2-z1;
double L=sqrt(x*x+y*y+z*z);
GLUquadricObj *quadObj;
GLUquadric* cyl = gluNewQuadric();
GLUquadric* cy2 = gluNewQuadric();
GLUquadric* cy3 = gluNewQuadric();
glPushMatrix ();
glTranslated(x1,y1,z1);
if((x!=0.)||(y!=0.)) {
glRotated(atan2(y,x)/RADPERDEG,0.,0.,1.);
glRotated(atan2(sqrt(x*x+y*y),z)/RADPERDEG,0.,1.,0.);
} else if (z<0){
glRotated(180,1.,0.,0.);
}
//glTranslatef(0,0,L-4*D);
gluQuadricDrawStyle(cyl, GLU_FILL);
gluQuadricNormals(cyl, GLU_SMOOTH);
glTranslatef(0,0,0);
glColor3f(1,1,1);
gluQuadricDrawStyle(cyl, GLU_FILL);
//gluQuadricNormals(cyl, GLU_SMOOTH);
gluCylinder(cyl, 0.1, 0.1,4.0, 12,1);
//glColor3f (1,1,1);
glColor3f(1,1,1);
glTranslatef(0.0,0.0,4);
glColor3f(1,1,1);
gluQuadricNormals(cyl, GLU_SMOOTH);
gluCylinder(cy2, 0.2, 0,0.4, 12,1);
gluDeleteQuadric(cyl);
glPopMatrix();
}
this function call others :
void Golsa::drawSub()
{
float Xangle, Yangle, Zangle;
float Xposition, Yposition, Zposition;
/*Mat rvec1i = Mat(3,1,CV_64FC1,Scalar::all(0));
Mat tvec1i = Mat(3,1,CV_64FC1,Scalar::all(0));*/
// set bottom viewport (perspective)
glViewport(0, 0, windowWidth, windowHeight);
glScissor(0, 0, windowWidth, windowHeight);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(FOV_Y, windowWidth/(windowHeight/2.0f), 1, 1000);
// switch to modelview matrix
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
// clear buffer
glClearColor(bgColor[0], bgColor[1], bgColor[2], bgColor[3]); // background color
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
glPushMatrix();
// First, transform the camera (viewing matrix) from world space to eye space
glTranslatef(0, 0, -cameraDistance);
glRotatef(cameraAngleX, 1, 0, 0); // pitch
glRotatef(cameraAngleY, 0, 1, 0); // heading
// draw grid
drawGrid(10, 1);
FindingCameraPosition(Xposition,Yposition,Zposition,Xangle,Yangle,Zangle);
glPopMatrix();
}

Answer 1

Turning my comment into an answer.
drawGrid() has a call to glBegin(), but no matching call to glEnd().