Hello,
I have to make a small game in C++ as a school project. Now, although I've made many 2D games before I'm very new to C++, and I ran into a few problems.
One: I need dynamic key input. I now use getch() and it makes the program wait for key input, but I want other code to keep running while no key is pressed yet.
Two: I think I have a memory leak or something, because if I keep running my game a few times, my pc becomes slower. (I have a dutch pc so can't describe it very clearly, but if you press CTRL+ALT+DEL, and look at the performance tab, and then the thing beneath the CPU gets higher everytime I play (from 178 MB to 200, to 300 and then my pc becomes kind of slow).
My code (the game's a very silly not-yet-working correctly car-racing game):
#include <cstdlib>
#include <iostream>
#include <string>
#include <conio.h>
#include <process.h>
using namespace std;
//car variables
string car("|=|");
string car_frontback("0-0");
string car_space_left("");
string car_space_right("");
int car_space_int = 10;
//int car_health = 100;
//enemy variables
string enemy("|=|");
string enemy_frontback("X=X");
string enemy_space_left("");
string enemy_space_right("");
int enemy_space_int = 0;
int enemy_pos = 0;
//game variables
int row_total = 15;
int space_total = 20;
string game_space(" ");
string line("|");
string show_nothing(" ");
int nothing[] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
int i = 0;
int num = 0;
//keyboard variables
const char KEYRIGHT = 75;
const char KEYLEFT = 77;
char arrow = 0;
int main(int argc, char *argv[])
{
//title screen
cout << " -----------------" << endl
<< " - Welcome -" << endl
<< " - to -" << endl
<< " - Ultra Car -" << endl
<< " - Racing -" << endl
<< " - 3000 -" << endl
<< " -----------------" << endl
<< "" << endl
<< "Use the left and right keys to dodge cars." << endl
<< "Press any key to start.";
srand(time(NULL));
//check keyboard
arrow = kbhit();
while(arrow !=27) {
//variables
i = 0;
car_space_left = "";
car_space_right = "";
enemy_space_left = "";
enemy_space_right = "";
//wait for kb input... why wait?! :( ..stupid c++
arrow = getch();
switch(arrow)
{
case KEYLEFT:
//left arrow key
if (car_space_int <= space_total) car_space_int+=1;
break;
case KEYRIGHT:
//right arrow key
if (car_space_int > 0) car_space_int-=1;
break;
}
//space left to the car
for (i=0; i < car_space_int; i++) {
car_space_left = car_space_left + " ";
}
//space right to the car
for (i=0; i <= space_total-car_space_int; i++) {
car_space_right = car_space_right + " ";
}
//set enemy position
if (enemy_pos == 14) {
num = 1 + rand() % (20 - 1 + 1);
enemy_space_int = num;
}
//space left to the enemy
for (i=0; i < enemy_space_int; i++) {
enemy_space_left = enemy_space_left + " ";
}
//space right to the enemy
for (i=0; i <= space_total-enemy_space_int; i++) {
enemy_space_right = enemy_space_right + " ";
}
enemy_pos += 1;
if (enemy_pos > row_total) {
enemy_pos = 0;
}
//clear screen
system("cls");
//place game screen lower
cout << endl;
cout << endl;
cout << endl;
//position of enemy
for (i=0; i<row_total; i++)
{
nothing[i] = 0;
}
nothing[enemy_pos] = 1;
nothing[enemy_pos+1] = 2;
nothing[enemy_pos+2] = 1;
//show road, enemy
for (i=0; i<row_total; i++) {
if (nothing[i] == 0) { show_nothing = " "; }
else if (nothing[i] == 1) { show_nothing = enemy_frontback; }
else if (nothing[i] == 2) { show_nothing = enemy; }
cout << game_space << line << enemy_space_left << show_nothing << enemy_space_right << line << endl;
}
//show car
cout << game_space << line << car_space_left << car_frontback << car_space_right << line << endl;
cout << game_space << line << car_space_left << car << car_space_right << line << endl;
cout << game_space << line << car_space_left << car_frontback << car_space_right << line << endl;
cout << endl << "check " << enemy_pos << " + " << i;
}
//end game
system("PAUSE");
return EXIT_SUCCESS;
}
//I HAVE A MEMORY LEAK SOMEWHERE!!! :(
Yes, I know my code is very very bad... this is the first time I use C++. And yes it's a text-based racing game... :eek:
Basically what it does now is that you can steer a car from left to right, and that other cars run down the road from top to bottom, but they only can down if you keep driving (no keyboard input and they stop moving).
Any help would be much appreciated!
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Marked 
