I have solved this problem,the code just like below:
void vBond::draw_me(int hit)
{
:) if(hit==0){glColor3f(0.75f,0.75f,1.0f);}else{glColor3f(1.0f,0.75f,0.75f);} ...

my object like this:
class vBond
{
public:
GLfloat x1,y1,z1;
vBond(string strName,string T_ptl,string T_ptr);
~vBond();
void draw_me(int hit);
void Computelocation(GLfloat xx,GLfloat...