where do i put in my rotate function - c++

Question

#include "std_lib_facilities.h"
#include <GL/glut.h>
static float dx=0.0;
static float dz=10;
static float points[2];
static float cx=0.0;
static float cy=0.0;
static float cz=0.0;
static float spin=0.0;
static float rotation=1.0;
int readObject()
{
ifstream inputFile("spikeBall.ogl");
if(!inputFile)
{
cerr << "cannot open file spikeBall.ogl" << endl;
return -1;
}
int count = 0;
float x,y,z;
do{
inputFile >> count;
glBegin(GL_POLYGON);
for(int i=0;i<count;i++)
{
inputFile >> x >> y >> z;
glVertex3f(((x/5)+cx),((y/5)+cy),((z/5)+cz));
}
glEnd();
}while(count!=0);
inputFile.close();
}
void init(void)
{
glClearColor(0.0,0.0,0.0,0.0);
}
void display(void)
{
glClear (GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glEnable(GL_DEPTH_TEST);
glLoadIdentity();
gluLookAt (0,0,20, 0.0,0.0,0.0, 0.0,1.0,0.0);
glPushMatrix();
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
GLfloat aMaterial[]={0.1745,0.01175,0.01175,1.0};
GLfloat bMaterial[]={0.61424,0.04136,0.04136,1.0};
GLfloat cMaterial[]={0.727811,0.626959,0.626959,1.0};
GLfloat dMaterial=40;
glMaterialfv(GL_FRONT,GL_AMBIENT,aMaterial);
glMaterialfv(GL_FRONT,GL_DIFFUSE,bMaterial);
glMaterialfv(GL_FRONT,GL_SPECULAR,cMaterial);
glMaterialf(GL_FRONT,GL_SHININESS,dMaterial);
readObject();
glRotatef(spin,0.0,1.0,0.0);
glPopMatrix();
glFlush();
}
void idleFunc(void)
{
spin+=rotation;
if(spin>360.0)
{
spin-=360.0;
}
cz+=0.1;
if(cz==20)
{
srand((unsigned int) time(NULL));
for(int i=0;i<2;i++)
{
points[i] = (rand()%20)-10;
}
cx = points[0];
cy = points[1];
cz = 0;
GLfloat lightPos[] = {cx,cy,(cz+2),1.0};
glLightfv(GL_LIGHT0,GL_POSITION,lightPos);
std::cout << "cx:" << cx;
std::cout << "cy:" << cy;
std::cout << "cz:" << cz;
}
else
{
}
glutPostRedisplay();
}
void reshape (int w, int h)
{
glViewport (0, 0, (GLsizei) w, (GLsizei) h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(60.0, (GLfloat) w/(GLfloat) h, 1.0,20.0);
glMatrixMode(GL_MODELVIEW);
}
int main(int argc, char** argv)
{
glutInit(&argc,argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
glutInitWindowSize(300,300);
glutInitWindowPosition(0,0);
glutCreateWindow("3ds Max loader");
glutDisplayFunc(display);
glutReshapeFunc(reshape);
init();
glutIdleFunc(idleFunc);
glutMainLoop();
return(0);
}
iat the moment it's just moving forward, i want it to spin too, but everywhere i put it, it's either not spinning or it makes the sphere look like it just blew up ( like when i put it after glEnd())

Answer 1

I would create an update loop where you could call all of your logic functions, and create a new seperate Rotate() function then call it there. The general format for games programming I usually follow is:
main()
{
init();
while(gameOn)
{
update();
draw();
}
}
init()
{
//create textures, etc.
}
update()
{
//do logic
}
draw()
{
//display on screen after update
}