allegro 5 no events work - c++

no events work in my "game" if I test the actions themselves that should happen (like if I put the moving function into the loop itself or the firing function, it works perfectly), but no event works, closing the display, with esc or pressing X, any pressed key, nothing is seen.
I cannot find the mistake in my code, could anyone please help? The game loop is bellow and all of the main function is here : http://pastebin.ca/2468619
while(!done)
{
ALLEGRO_EVENT ev;
al_wait_for_event(event_queue, &ev);
if(ev.type == ALLEGRO_EVENT_DISPLAY_CLOSE)
{
std::cout << "EXITING MOFO";
done= true;
}
else if(ev.type == ALLEGRO_KEY_DOWN)
{
switch(ev.keyboard.keycode)
{
case ALLEGRO_KEY_ESCAPE:
done = true;
break;
case ALLEGRO_KEY_A:
keys[A] = true;
break;
case ALLEGRO_KEY_S:
keys[S] = true;
break;
case ALLEGRO_KEY_D:
keys[D] = true;
break;
case ALLEGRO_KEY_W:
keys[W] = true;
break;
case ALLEGRO_KEY_SPACE:
fireWeapon(0);
break;
case ALLEGRO_KEY_LEFT:
keys[LEFT] = true;
break;
case ALLEGRO_KEY_RIGHT:
keys[RIGHT] = true;
break;
case ALLEGRO_KEY_UP:
keys[UP] = true;
break;
case ALLEGRO_KEY_DOWN:
keys[DOWN] = true;
break;
case ALLEGRO_KEY_ENTER:
std::cout << "FUCK";
fireWeapon(1);
break;
}
}
else if(ev.type == ALLEGRO_KEY_UP)
{
switch(ev.keyboard.keycode)
{
case ALLEGRO_KEY_A:
keys[A] = false;
break;
case ALLEGRO_KEY_S:
keys[S] = false;
break;
case ALLEGRO_KEY_D:
keys[D] = false;
break;
case ALLEGRO_KEY_W:
keys[W] = false;
break;
case ALLEGRO_KEY_LEFT:
keys[LEFT] = false;
break;
case ALLEGRO_KEY_RIGHT:
keys[RIGHT] = false;
break;
case ALLEGRO_KEY_UP:
keys[UP] = false;
break;
case ALLEGRO_KEY_DOWN:
keys[DOWN] = false;
break;
}
}
else if(ev.type == ALLEGRO_EVENT_TIMER)
{
render = true;
moveTank();
updateBullet(0);
updateBullet(1);
}
if(render && al_is_event_queue_empty(event_queue))
{
render = false;
//al_set_target_bitmap(back);
//al_clear_to_color(al_map_rgb(0,0,0));
drawTank(0);
drawTank(1);
drawBullet(0);
drawBullet(1);
//setupDebris();
al_flip_display();
al_clear_to_color(al_map_rgb(0,0,0));
}

I watched the same tutorial.
You have to add
al_register_event_source(event_queue, al_get_display_event_source(display))
to main.

Related

The better way to control player in 2d game ? (sdl2)

I'm doing this like this, in .hpp file:
class Player
{
public:
Player(){}
Player(){}
virtual ~Player(){}
void handler(SDL_Event event);
void update()
{
move(velocityForwardX, velocityForwardY);
move(-velocityBackwardX, -velocityBackwardY);
/* the player moves from it current position. */
}
protected:
int speed = 5;
int velocityForwardX = 0;
int velocityForwardY = 0;
int velocityBackwardX = 0;
int velocityBackwardY = 0;
};
in .cpp file:
#include "Player.h"
void Player::handler(SDL_Event event)
{
if(event.type == SDL_KEYDOWN){
switch(event.key.keysym.sym)
{
case SDLK_d:
velocityForwardX = speed;
break;
case SDLK_q:
velocityBackwardX = speed;
break;
case SDLK_z:
velocityBackwardY = speed;
break;
case SDLK_s:
velocityForwardY = speed;
break;
default:
break;
}
}
else if(event.type == SDL_KEYUP){
switch(event.key.keysym.sym)
{
case SDLK_d:
velocityForwardX = 0;
break;
case SDLK_q:
velocityBackwardX = 0;
break;
case SDLK_z:
velocityBackwardY = 0;
break;
case SDLK_s:
velocityForwardY = 0;
break;
default:
break;
}
}}
like this I can presse any key and release it and the player move well. It also works if two opposite keys are pressed then one is release so the player is going in the right direction. Can we make it easier ? (sorry for my english)
You could store only one variable per direction and add and subtract speed when pressing and releasing a button, e.g.
switch(event.key.keysym.sym)
{
case SDLK_d:
velocityX += speed;
break;
case SDLK_q:
velocityX -= speed;
break;
case SDLK_z:
velocityY -= speed;
break;
case SDLK_s:
velocityY += speed;
break;
default:
break;
}
// similar for key release
With this if you press opposite x direction keys simultaniously, velocityX will be 0, and the same for the y direction and velocityY.

How to stop linear rectangle movement from stuttering in sdl2

Here is the code for moving the rectangle while w is pressed
while (SDL_PollEvent(&e) != 0) {
if (e.type == SDL_QUIT)
{
done = false;
}
if (e.type = SDL_KEYDOWN)
{
switch (e.key.keysym.sym)
{
case SDLK_w:
SDL_RenderFillRect(renderer, &player);
player.y -=SPEED;
draw();
break;
case SDLK_s:
SDL_RenderFillRect(renderer, &player);
player.y +=SPEED;
draw();
break;
default:
break;
}
}
}
everything works fine except when it runs it stutters. the rectangle moves by stuttering and it's very annoying

Handling multiple keypressess at the same time in SDL

I'm making a simple top down 2D shooter, where you move with WASD and shoot in the direction you're looking at with space. I can move and shoot just fine, but I can't do them both at the same time. For example if I'm shooting and start moving, my character will stop shooting until I release and press space again, and if I then start moving in another direction I have to release and press space again.
Here's my main method:
int main(int argc, char* args[])
{
if (!init())
{
log("Failed to initialize!\n");
}
else
{
log("Initialized SDL and SDL subsystems. \nLoading assets:\n");
if (!loadAssets())
{
printf("Failed to load assets!\n");
}
else
{
log("All assets loaded successfully.\n");
bool running = true;
SDL_Event e;
std::vector<Shot> shots;
LTimer shotTimer;
float cooldown = 250.0f;
float previousCooldown = 0.0f;
Player player;
log("Game running.\n");
shotTimer.start();
while (running)
{
while (SDL_PollEvent(&e) != 0)
{
if (e.type == SDL_QUIT)
{
log("SDL_QUIT event triggered.\n");
running = false;
}
else if (e.type == SDL_KEYDOWN)
{
switch (e.key.keysym.sym)
{
case SDLK_ESCAPE:
{
running = false;
break;
}
}
}
player.handleEvent(e);
if (SDL_GetTicks() - previousCooldown > cooldown)
{
previousCooldown = SDL_GetTicks();
shots = shoot(e, player, shots);
}
}
player.move();
for (int i = 0; i < shots.size(); i++)
{
shots[i].move();
}
/*if (shotTimer.getTicks() >= cooldown)
shotTimer.restart();*/
SDL_SetRenderDrawColor(renderer, 0xff, 0xff, 0xff, 0xff);
SDL_RenderClear(renderer);
background.render(0, 0);
for (int i = 0; i < shots.size(); i++)
{
shots[i].render();
}
player.render();
SDL_RenderPresent(renderer);
}
}
}
close();
return 0;
}
Here's my shoot() function, which is probably what's causing this:
std::vector<Shot> shoot(SDL_Event& e, Player player, std::vector<Shot> shots)
{
bool shoot = false;
if (e.type = SDL_KEYDOWN && e.key.repeat == 1)
{
switch (e.key.keysym.sym)
{
case SDLK_SPACE:
{
shoot = true;
break;
}
}
}
else if (e.type = SDL_KEYUP && e.key.repeat == 1)
{
switch (e.key.keysym.sym)
{
case SDLK_SPACE:
{
shoot = false;
break;
}
}
}
if (shoot)
{
Shot newShot(player.getDir(), player);
shots.push_back(newShot);
}
return shots;
}
And this is how I move the player
void Player::handleEvent(SDL_Event& e)
{
if (e.type == SDL_KEYDOWN && e.key.repeat == 0)
{
switch (e.key.keysym.sym)
{
case SDLK_w: mVelY -= PLAYER_VEL; mDir = 0; break;
case SDLK_s: mVelY += PLAYER_VEL; mDir = 1; break;
case SDLK_d: mVelX += PLAYER_VEL; mDir = 2; break;
case SDLK_a: mVelX -= PLAYER_VEL; mDir = 3; break;
}
}
else if (e.type == SDL_KEYUP && e.key.repeat == 0)
{
switch (e.key.keysym.sym)
{
case SDLK_w: mVelY += PLAYER_VEL; break;
case SDLK_s: mVelY -= PLAYER_VEL; break;
case SDLK_d: mVelX -= PLAYER_VEL; break;
case SDLK_a: mVelX += PLAYER_VEL; break;
}
}
}
Separate your event polling from the rest of the game logic.
Poll all events once per frame in a separate function and store the state of the keystates into an array. Then, when you need the state, simply check the array.
You can also use SDL_GetKeyboardState to sample the surrent state of the keys, without having to handle the key events yourself.

Move an item in a scene Qt

I try to move an item in a scene and for that, I use QKeypressEvent and moveBy that works both perfectly but I'd like to recover the "key press event", so I decided first, to use a boolean that returns true when the key is pressed and false when it's not, and then to create a new function where I call the moveBy if my boolean is true, but unfortunately is doesn't work.
This is what I've done in my file.cpp
Perso::Perso()
{
right= false;
left= false;
up= false;
down= false;
moveOnMap();
setFlag(QGraphicsItem::ItemIsFocusable);
}
void Perso::moveOnMap(){
if (left) {
moveBy(-10,0);
}
if (right) {
moveBy(10,0);
}
if (up) {
moveBy(0, -10);
}
if (down) {
moveBy(0, +10);
}
}
void Perso::keyPressEvent(QKeyEvent *event){
switch(event->key()){
case Qt::Key_Up:
up=true;
//moveBy(0, -10);
break;
case Qt::Key_Right:
right=true;
// moveBy(10,0);
break;
case Qt::Key_Left:
left=true;
//moveBy(-10,0);
break;
case Qt::Key_Down:
down= true;
//moveBy(0, 10);
break;
}
update();
}
void Perso::keyReleaseEvent(QKeyEvent *event){
switch(event->key()){
case Qt::Key_Up:
up=false;
break;
case Qt::Key_Right:
right= false;
break;
case Qt::Key_Left:
left= false;
break;
case Qt::Key_Down:
down= false;
break;
}
}
Anyone can help me to understand where I am wrong?
I can't see here that you call your moveOnMap(); If in your original code you don't call this method that it is normal that it is not work. You call it only in constructor but you should call this method every key pressing. So try to call this method in your key events:
void Perso::keyPressEvent(QKeyEvent *event){
switch(event->key()){
case Qt::Key_Up:
up=true;
//moveBy(0, -10);
break;
case Qt::Key_Right:
right=true;
// moveBy(10,0);
break;
case Qt::Key_Left:
left=true;
//moveBy(-10,0);
break;
case Qt::Key_Down:
down= true;
//moveBy(0, 10);
break;
}
moveOnMap();
update();
}
void Perso::keyReleaseEvent(QKeyEvent *event){
switch(event->key()){
case Qt::Key_Up:
up=false;
break;
case Qt::Key_Right:
right= false;
break;
case Qt::Key_Left:
left= false;
break;
case Qt::Key_Down:
down= false;
break;
}
moveOnMap();
}

SDLK_F1 key case not working

I am trying to catch the event for F1 key in SDL in C++.
But,somehow i cannot see any changes after pressing the F1 key.But,when i wnat to toggle my animation objects on the screen i make use SDL_t case to do so,and it is executing fine.
Just not geting why is it not taking the F1 key.
Here is the switch case for handling key press events:
SDL_Event event;
bool done = false;
bool keyPress = false;
while ( not done ) {
draw();
SDL_Flip(screen);
SDL_PollEvent(&event);
if (event.type == SDL_QUIT) { break; }
if(event.type == SDL_KEYUP) { keyCatch = false; }
if(event.type == SDL_KEYDOWN) {
switch ( event.key.keysym.sym ) {
case SDLK_ESCAPE : done = true; break;
case SDLK_q : done = true; break;
case SDLK_F1 : {
if(!keyCatch){
keyPress=true;
//this method is from another class.
io.printMessageAt("F1 is selected:",50,10);
currentOrb = (currentOrb+1) % orbs.size();
}
break;
}
case SDLK_t : case SDLK_SPACE :
if ( !keyPress ) {
//something
}
break;
case SDLK_p : {
if (!keyPress) {
keyPress = true;
//something
}
break;
}
default : break;
}
}
}
NOTE: i cannot give the entire code here.The above is my part what i am trying to do.
Double-check that your window manager or a hotkey daemon isn't consuming your F1's before they hit your process.
This works fine (F1 closes the program) on my system:
#include <SDL.h>
int main( int, char** )
{
SDL_Init(SDL_INIT_EVERYTHING);
SDL_Surface* screen = SDL_SetVideoMode(640, 480, 32, SDL_ANYFORMAT);
SDL_Event event;
bool done = false;
bool keyPress = false;
while ( !done )
{
SDL_Flip(screen);
SDL_PollEvent(&event);
if(event.type == SDL_QUIT)
{
break;
}
if(event.type == SDL_KEYUP)
{
keyPress = false;
}
if(event.type == SDL_KEYDOWN)
{
switch ( event.key.keysym.sym )
{
case SDLK_ESCAPE:
case SDLK_q:
done = true;
break;
case SDLK_F1:
if(!keyPress)
{
keyPress=true;
done = true;
}
break;
case SDLK_t:
case SDLK_SPACE:
if ( !keyPress )
{
//something
}
break;
case SDLK_p:
if (!keyPress)
{
keyPress = true;
//something
}
break;
default:
break;
}
}
}
SDL_Quit();
return 0;
}
I did notice that keyCatch was undefined. I replaced it with keyPress.