game loop not working ncurses - c++

Question

I'm new to ncurses and we have a project to create a game of our choice.
The idea of my game is to have a spaceship and have enemies attack from the top.
I only started the code and I already ran into a problem, when i use the space bar to shoot a bullet, the bullet will travel, however i am unable to move my ship at the same time the bullet is moving.
#include<ncurses.h>
typedef struct
{/*define a structure for player information*/
int row;
int col;
}playerinfo;
int changeRow(int x,int m, int c)
{
if(x+m==22 || x+m==0 )
{
beep();
return x;
}
return x+m;
}
int changeColumn(int y,int n, int r)
{
if(y+n==72 || y+n==0 )
{
beep();
return y;
}
return y+n;
}
int main(){
initscr();
start_color();
assume_default_colors(COLOR_GREEN, COLOR_BLACK);
noecho();
cbreak();
curs_set(0); /* turn cursor display off */
timeout(0);
keypad(stdscr,TRUE); /* allow keypad keys to be used */
playerinfo playership;
playership.row= 10;
playership.col= 15;
char player[] =" X ";
char player2[]=" |o| ";
char player3[]=" xX| |Xx ";
char player4[]=" X | | X ";
char player5[]=" X__-|-__X ";
char bullet = '.';
int key = 0;
int i=0;
bool moving= false;
mvprintw(playership.row,playership.col,player);
mvprintw(playership.row+1,playership.col,player2);
mvprintw(playership.row+2,playership.col,player3);
mvprintw(playership.row+3,playership.col,player4);
mvprintw(playership.row+4,playership.col,player5);
timeout(0);
while(key!='q'){
usleep(17000);
mvprintw(playership.row,playership.col," ");
mvprintw(playership.row+5,playership.col," ");
key = getch ();
switch(key){
case KEY_UP: playership.row=changeRow(playership.row,-1,playership.col); /* move up */
break;
case KEY_DOWN: playership.row=changeRow(playership.row,+1,playership.col); /* move down */
break;
case KEY_LEFT:playership.col=changeColumn(playership.col,-1,playership.row); /* move left */
break;
case KEY_RIGHT:playership.col=changeColumn(playership.col,+1,playership.row); /* move right */
break;
case ' ': moving=true; break;
default: break; /* do nothing if other keys */
}
mvprintw(playership.row,playership.col,player);
mvprintw(playership.row+1,playership.col,player2);
mvprintw(playership.row+2,playership.col,player3);
mvprintw(playership.row+3,playership.col,player4);
mvprintw(playership.row+4,playership.col,player5);
if (moving==true){
for( i=0; i <24; i++){
refresh; mvprintw(playership.row-i-2,playership.col+5,"%c", bullet); mvprintw(playership.row,playership.col,player);
refresh();usleep(12000); mvprintw(playership.row-i-1,playership.col+5," ");} moving=false; }
refresh();
}
echo(); /* turn echo back on */
endwin(); /* End curses mode */
return 0;
}

Answer 1

That is because you nested the "firing" code inside your game loop, so all input stops while you do that animation. You need to change your logic to a kind of state machine:
switch(key)
{
// ...
case ' ':
if( !bullet_active )
{
bullet_active = true;
bullet_pos = 0;
}
break;
}
if( bullet_active ) {
// TODO: Draw bullet at bullet_pos
if( ++bullet_pos == 24 ) bullet_active = false;
}