Creating a array of class objects (C++) [duplicate] - c++

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This question already has answers here:
How do I use arrays in C++?
(5 answers)
Closed 7 years ago.
I have been trying to make a simulator which involves ants randomly running around (for now...) I want to make a array of "Ant" to contain all my ant information and later functions. How would I do that?? (example with my code if possible)(I know java fairly well so if you could relate it to java that would be nice
//inclusions
#include <GLUT/glut.h>
#include <OpenGL/glu.h>
#include <OpenGL/gl.h>
#include <stdio.h>
#include <math.h>
#include <stdlib.h>
//declarations
//class declarations
void keyboard (unsigned char key, int x, int y);
void keyboardUp (unsigned char key, int x, int y);
void mouseLocation(int,int);
int onMouse;
int rightClick;
int a = 0;
int mx;
int my;
float red=1.0, blue=0, green=0;
class Ant {
int x;
int y;
int type;
Ant() { } // private default constructor
public:
Ant(int nx, int ny, int ntype)
{
x = nx;
y = ny;
type = ntype;
}
void SetX(int swagger)
{
x = swagger;
}
void SetY(int ny)
{
y = ny;
}
void SetType(int ntype)
{
type = ntype;
}
int GetX() { return x; }
int GetY() { return y; }
};
//mouse listener methods
void mouseLocation(int x,int y) {
mx = x;
my = y;
}
void mouseClicks(int button, int state, int x, int y) {
mx = x;
my = y;
if(button == GLUT_LEFT_BUTTON && state == GLUT_DOWN) {
onMouse = 1;
}
if(button == GLUT_LEFT_BUTTON && state == GLUT_UP) {
onMouse = 0;
}
if(button == GLUT_RIGHT_BUTTON && state == GLUT_UP) {
rightClick = 0;
}
if(button == GLUT_RIGHT_BUTTON && state == GLUT_DOWN) {
rightClick = 1;
}
}
//keylistner methods
void keyboard (unsigned char key, int x, int y)
{
if (key == 'a')
{
a = 1;
}
}
void keyboardUp (unsigned char key, int x, int y)
{
if(key == 'a')
{
a = 0;
}
}
//ant methods
int randommove(int position,int speed)
{
speed++;
int random = rand() %speed - speed/2 ;
position = position + random;
return position;
}
//drawing methods
Ant ant1(100,100,1);
Ant ant2(50,500,1);
//Here is the where I want to try the ant array something like
//Ant ants[x] and then I would fill in the values with the SetX, SetY... methods
void ant()
{
int a2 = randommove(ant1.GetX(),2);
ant1.SetX(a2);
glLineWidth(1);
glBegin(GL_LINES);
glColor4f(1, 0, 0, 1);
glVertex2i(ant1.GetX(),ant1.GetY());
glVertex2i(ant1.GetX()+5,ant1.GetY()+5);
glEnd();
}
void line1()
{
if(a == 1)
{
glLineWidth(2.5);
glBegin(GL_LINES);
glVertex2i(80,20);
glVertex2i(100,400);
glEnd();
}
}
void line2()
{
if(onMouse == 1)
{
glLineWidth(2.5);
glBegin(GL_LINES);
glVertex2i(200,20);
glVertex2i(100,400);
glEnd();
}
}
void rect1()
{
if(mx >= 50 && my >= 50)
{
int x = 100;
int y = 100;
int w = 100;
int h = 100;
unsigned int rgba = 0xff0000ff; // red, no alpha
glBegin(GL_QUADS);
glColor4f(((rgba>>24)&0xff)/255.0f,
((rgba>>16)&0xff)/255.0f,
((rgba>>8)&0xff)/255.0f,
(rgba&0xff)/255.0f);
glVertex3f(x,y,0);
glVertex3f(x+w,y,0);
glVertex3f(x+w,y+h,0);
glVertex3f(x,y+h,0);
glEnd();
glColor4f(1, 1, 1, 1);
}
}
void rect2()
{
if(rightClick == 1)
{
int w = 100;
int h = 100;
unsigned int rgba = 0xff0000ff; // red, no alpha
glBegin(GL_QUADS);
glColor4f(((rgba>>24)&0xff)/255.0f,
((rgba>>16)&0xff)/255.0f,
((rgba>>8)&0xff)/255.0f,
(rgba&0xff)/255.0f);
glVertex3f(mx,my,0);
glVertex3f(mx+w,my,0);
glVertex3f(mx+w,my+h,0);
glVertex3f(mx,my+h,0);
glEnd();
glColor4f(1, 1, 1, 1);
}
}
//render drawing methods
void renderScence(void){
glClear (GL_COLOR_BUFFER_BIT);
glColor3f(red, green, blue);
ant();
line1();
line2();
rect1();
rect2();
glFlush();
}
//graphics init method
void init(void)
{
glutInitDisplayMode(GLUT_SINGLE |GLUT_RGB);
glutInitWindowSize (500,500);
glutInitWindowPosition (100, 100);
glutCreateWindow ("Testing");
glClearColor (0, 0, 0, 1.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(0, 500, 0, 500);
}
//main/graphics calls
int main(int argc,char** argv)
{
glutInit(&argc, argv);
init();
glutDisplayFunc(renderScence);
glutIdleFunc(renderScence);
glutMouseFunc(mouseClicks);
glutPassiveMotionFunc(mouseLocation);
glutKeyboardUpFunc (keyboardUp);
glutKeyboardFunc (keyboard);
glutMainLoop();
return 0;
}

Answer 1

You could create the array of Ant objects inside main, and it's the same way you'd create any other array except it's of type Ant:
Ant ants[25]; // 25 Ant objects
/* to set them all the same, as an example */
for(i=0; i<25; i++)
{
ants[i].SetX(1); // x = 1
ants[i].SetY(2); // y = 2
ants[i].SetType(3); // type = 3
}