I'm wondering if anyone can point me in the right direction for this error.
I am learning 2D game programming using Allegro 5 installed in Visual Studio 2010. I have been following a tutorial series and everything has been fine until the last lesson.
The final code will build successfully. The executable will load but will crash out when I hit the space bar to fire a bullet (it's a side shooter game). I get the following error:
"Assertion failed: spl, file allegro-git\addons\audio\kgm_sample.c line 321"
It obviously has something to do with the bullet sample sound linked in with the key press.
If I comment out the line: al_play_sample(shot, 1, 0, 1, ALLEGRO_PLAYMODE_ONCE, 0); in the FireBullet() function, then the game will play fine (without the bullet sound).
I have searched everywhere and cannot find a solution.
Here is the complete code for the game:
#include <allegro5\allegro.h>
#include <allegro5\allegro_primitives.h>
#include <allegro5\allegro_font.h>
#include <allegro5\allegro_ttf.h>
#include <allegro5\allegro_image.h>
#include <allegro5\allegro_audio.h>
#include <allegro5\allegro_acodec.h>
#include "objects.h"
//GLOBALS==============================
const int WIDTH = 800;
const int HEIGHT = 400;
const int NUM_BULLETS = 5;
const int NUM_COMETS = 10;
const int NUM_EXPLOSIONS = 5;
enum STATE{TITLE, PLAYING, LOST};
enum KEYS{UP, DOWN, LEFT, RIGHT, SPACE};
bool keys[5] = {false, false, false, false, false};
SpaceShip ship;
Bullet bullets[NUM_BULLETS];
Comet comets[NUM_COMETS];
Explosion explosions[NUM_EXPLOSIONS];
ALLEGRO_SAMPLE *shot = NULL;
ALLEGRO_SAMPLE *boom = NULL;
ALLEGRO_SAMPLE *song = NULL;
ALLEGRO_SAMPLE_INSTANCE *songInstance = NULL;
//prototypes
void InitShip(SpaceShip &ship, ALLEGRO_BITMAP *image);
void ResetShipAnimation(SpaceShip &ship, int position);
void DrawShip(SpaceShip &ship);
void MoveShipUp(SpaceShip &ship);
void MoveShipDown(SpaceShip &ship);
void MoveShipLeft(SpaceShip &ship);
void MoveShipRight(SpaceShip &ship);
void InitBullet(Bullet bullet[], int size);
void DrawBullet(Bullet bullet[], int size);
void FireBullet(Bullet bullet[], int size, SpaceShip &ship);
void UpdateBullet(Bullet bullet[], int size);
void CollideBullet(Bullet bullet[], int bSize, Comet comets[], int cSize, SpaceShip &ship, Explosion explosions[], int eSize);
void InitComet(Comet comets[], int size, ALLEGRO_BITMAP *image);
void DrawComet(Comet comets[], int size);
void StartComet(Comet comets[], int size);
void UpdateComet(Comet comets[], int size);
void CollideComet(Comet comets[], int cSize, SpaceShip &ship, Explosion explosions[], int eSize);
void InitExplosions(Explosion explosions[], int size, ALLEGRO_BITMAP *image);
void DrawExplosions(Explosion explosions[], int size);
void StartExplosions(Explosion explosions[], int size, int x, int y);
void UpdateExplosions(Explosion explosions[], int size);
void InitBackground(Background &back, float x, float y, float velX, float velY, int width, int height, int dirX, int dirY, ALLEGRO_BITMAP *image);
void UpdateBackground(Background &back);
void DrawBackground(Background &back);
void ChangeState(int &state, int newState);
int main(void)
{
//primitive variable
bool done = false;
bool redraw = true;
const int FPS = 60;
int state = -1;
//object variables
Background BG;
Background MG;
Background FG;
//Allegro variables
ALLEGRO_DISPLAY *display = NULL;
ALLEGRO_EVENT_QUEUE *event_queue = NULL;
ALLEGRO_TIMER *timer = NULL;
ALLEGRO_FONT *font18 = NULL;
ALLEGRO_BITMAP *shipImage;
ALLEGRO_BITMAP *cometImage;
ALLEGRO_BITMAP *expImage;
ALLEGRO_BITMAP *title = NULL;
ALLEGRO_BITMAP *lost = NULL;
ALLEGRO_BITMAP *bgImage = NULL;
ALLEGRO_BITMAP *mgImage = NULL;
ALLEGRO_BITMAP *fgImage = NULL;
//Initialization Functions
if(!al_init()) //initialize Allegro
return -1;
display = al_create_display(WIDTH, HEIGHT); //create our display object
if(!display) //test display object
return -1;
al_init_primitives_addon();
al_install_keyboard();
al_init_font_addon();
al_init_ttf_addon();
al_init_image_addon();
al_install_audio();
al_init_acodec_addon();
event_queue = al_create_event_queue();
timer = al_create_timer(1.0 / FPS);
shipImage = al_load_bitmap("spaceship_by_arboris.png");
al_convert_mask_to_alpha(shipImage, al_map_rgb(255, 0, 255));
cometImage = al_load_bitmap("asteroids.png");
expImage = al_load_bitmap("explosion.png");
title = al_load_bitmap("Shooter_Title.png");
lost = al_load_bitmap("Shooter_Lose.png");
bgImage = al_load_bitmap("starBG.png");
mgImage = al_load_bitmap("starMG.png");
fgImage = al_load_bitmap("starFG.png");
al_reserve_samples(10);
shot = al_load_sample("shot.ogg");
boom = al_load_sample("explosion.wav");
song = al_load_sample("war.wav");
songInstance = al_create_sample_instance(song);
al_set_sample_instance_playmode(songInstance, ALLEGRO_PLAYMODE_LOOP);
al_attach_sample_instance_to_mixer(songInstance, al_get_default_mixer());
srand(time(NULL));
ChangeState(state, TITLE);
InitShip(ship, shipImage);
InitBullet(bullets, NUM_BULLETS);
InitComet(comets, NUM_COMETS, cometImage);
InitExplosions(explosions, NUM_EXPLOSIONS, expImage);
InitBackground(BG, 0, 0, 1, 0, 800, 400, -1, 1, bgImage);
InitBackground(MG, 0, 0, 2, 0, 2400, 400, -1, 1, mgImage);
InitBackground(FG, 0, 0, 4, 0, 2400, 400, -1, 1, fgImage);
font18 = al_load_font("arial.ttf", 18, 0);
al_register_event_source(event_queue, al_get_keyboard_event_source());
al_register_event_source(event_queue, al_get_timer_event_source(timer));
al_register_event_source(event_queue, al_get_display_event_source(display));
al_start_timer(timer);
while(!done)
{
ALLEGRO_EVENT ev;
al_wait_for_event(event_queue, &ev);
if(ev.type == ALLEGRO_EVENT_TIMER)
{
redraw = true;
if(keys[UP])
MoveShipUp(ship);
else if(keys[DOWN])
MoveShipDown(ship);
else
ResetShipAnimation(ship, 1);
if(keys[LEFT])
MoveShipLeft(ship);
else if(keys[RIGHT])
MoveShipRight(ship);
else
ResetShipAnimation(ship, 2);
if(state == TITLE)
{}
else if(state == PLAYING)
{
UpdateBackground(BG);
UpdateBackground(MG);
UpdateBackground(FG);
UpdateExplosions(explosions, NUM_EXPLOSIONS);
UpdateBullet(bullets, NUM_BULLETS);
StartComet(comets, NUM_COMETS);
UpdateComet(comets, NUM_COMETS);
CollideBullet(bullets, NUM_BULLETS, comets, NUM_COMETS, ship, explosions, NUM_EXPLOSIONS);
CollideComet(comets, NUM_COMETS, ship, explosions, NUM_EXPLOSIONS);
if(ship.lives <= 0)
ChangeState(state, LOST);
}
else if(state == LOST)
{}
}
else if(ev.type == ALLEGRO_EVENT_DISPLAY_CLOSE)
{
done = true;
}
else if(ev.type == ALLEGRO_EVENT_KEY_DOWN)
{
switch(ev.keyboard.keycode)
{
case ALLEGRO_KEY_ESCAPE:
done = true;
break;
case ALLEGRO_KEY_UP:
keys[UP] = true;
break;
case ALLEGRO_KEY_DOWN:
keys[DOWN] = true;
break;
case ALLEGRO_KEY_LEFT:
keys[LEFT] = true;
break;
case ALLEGRO_KEY_RIGHT:
keys[RIGHT] = true;
break;
case ALLEGRO_KEY_SPACE:
keys[SPACE] = true;
if(state == TITLE)
ChangeState(state, PLAYING);
else if(state ==PLAYING)
FireBullet(bullets, NUM_BULLETS, ship);
else if(state == LOST)
ChangeState(state, PLAYING);
break;
}
}
else if(ev.type == ALLEGRO_EVENT_KEY_UP)
{
switch(ev.keyboard.keycode)
{
case ALLEGRO_KEY_ESCAPE:
done = true;
break;
case ALLEGRO_KEY_UP:
keys[UP] = false;
break;
case ALLEGRO_KEY_DOWN:
keys[DOWN] = false;
break;
case ALLEGRO_KEY_LEFT:
keys[LEFT] = false;
break;
case ALLEGRO_KEY_RIGHT:
keys[RIGHT] = false;
break;
case ALLEGRO_KEY_SPACE:
keys[SPACE] = false;
break;
}
}
if(redraw && al_is_event_queue_empty(event_queue))
{
redraw = false;
if(state == TITLE)
{
al_draw_bitmap(title, 0, 0, 0);
}
else if(state == PLAYING)
{
DrawBackground(BG);
DrawBackground(MG);
DrawBackground(FG);
DrawShip(ship);
DrawBullet(bullets, NUM_BULLETS);
DrawComet(comets, NUM_COMETS);
DrawExplosions(explosions, NUM_EXPLOSIONS);
al_draw_textf(font18, al_map_rgb(255, 0, 255), 5, 5, 0, "Player has %i lives left. Player has destroyed %i objects", ship.lives, ship.score);
}
else if(state == LOST)
{
al_draw_bitmap(lost, 0, 0, 0);
al_draw_textf(font18, al_map_rgb(0, 255, 255), WIDTH - 10, 20, ALLEGRO_ALIGN_RIGHT, "Final Score: %i", ship.score);
}
al_flip_display();
al_clear_to_color(al_map_rgb(0,0,0));
}
}
al_destroy_sample(shot);
al_destroy_sample(boom);
al_destroy_sample(song);
al_destroy_sample_instance(songInstance);
al_destroy_bitmap(bgImage);
al_destroy_bitmap(mgImage);
al_destroy_bitmap(fgImage);
al_destroy_bitmap(title);
al_destroy_bitmap(lost);
al_destroy_bitmap(expImage);
al_destroy_bitmap(cometImage);
al_destroy_bitmap(shipImage);
al_destroy_event_queue(event_queue);
al_destroy_timer(timer);
al_destroy_font(font18);
al_destroy_display(display); //destroy our display object
return 0;
}
void InitShip(SpaceShip &ship, ALLEGRO_BITMAP *image = NULL) {
ship.x = 20;
ship.y = HEIGHT / 2;
ship.ID = PLAYER;
ship.lives = 3;
ship.speed = 6;
ship.boundx = 10;
ship.boundy = 12;
ship.score = 0;
ship.maxFrame = 3;
ship.curFrame = 0;
ship.frameCount = 0;
ship.frameDelay = 50;
ship.frameWidth = 44;
ship.frameHeight = 41;
ship.animationColumns = 3;
ship.animationDirection = 1;
ship.animationRow = 1;
if(image != NULL)
ship.image = image;
}
void ResetShipAnimation(SpaceShip &ship, int position)
{
if(position == 1)
ship.animationRow = 1;
else
ship.curFrame = 0;
}
void DrawShip(SpaceShip &ship)
{
int fx =(ship.curFrame % ship.animationColumns) * ship.frameWidth;
int fy = ship.animationRow * ship.frameHeight;
al_draw_bitmap_region(ship.image, fx, fy, ship.frameWidth,
ship.frameHeight, ship.x - ship.frameWidth / 2, ship.y - ship.frameHeight / 2, 0);
/*al_draw_filled_rectangle(ship.x - ship.boundx, ship.y - ship.boundy, ship.x + ship.boundx,
ship.y + ship.boundy, al_map_rgba(255, 0, 255, 100));*/
}
void MoveShipUp(SpaceShip &ship)
{
ship.animationRow = 0;
ship.y -= ship.speed;
if(ship.y < 0)
ship.y = 0;
}
void MoveShipDown(SpaceShip &ship)
{
ship.animationRow = 2;
ship.y += ship.speed;
if(ship.y > HEIGHT)
ship.y = HEIGHT;
}
void MoveShipLeft(SpaceShip &ship)
{
ship.curFrame = 2;
ship.x -= ship.speed;
if(ship.x < 0)
ship.x = 0;
}
void MoveShipRight(SpaceShip &ship)
{
ship.curFrame = 1;
ship.x += ship.speed;
if(ship.x > 300)
ship.x = 300;
}
void InitBullet(Bullet bullet[], int size)
{
for(int i = 0; i < size; i++)
{
bullet[i].ID = BULLET;
bullet[i].speed = 10;
bullet[i].live = false;
}
}
void DrawBullet(Bullet bullet[], int size)
{
for( int i = 0; i < size; i++)
{
if(bullet[i].live)
al_draw_filled_circle(bullet[i].x, bullet[i].y, 2, al_map_rgb(255, 255, 255));
}
}
void FireBullet(Bullet bullet[], int size, SpaceShip &ship)
{
for( int i = 0; i < size; i++)
{
if(!bullet[i].live)
{
bullet[i].x = ship.x + 17;
bullet[i].y = ship.y;
bullet[i].live = true;
al_play_sample(shot, 1, 0, 1, ALLEGRO_PLAYMODE_ONCE, 0);
break;
}
}
}
void UpdateBullet(Bullet bullet[], int size)
{
for(int i = 0; i < size; i++)
{
if(bullet[i].live)
{
bullet[i].x += bullet[i].speed;
if(bullet[i].x > WIDTH)
bullet[i].live = false;
}
}
}
void CollideBullet(Bullet bullet[], int bSize, Comet comets[], int cSize, SpaceShip &ship, Explosion explosions[], int eSize)
{
for(int i = 0; i < bSize; i++)
{
if(bullet[i].live)
{
for(int j =0; j < cSize; j++)
{
if(comets[j].live)
{
if(bullet[i].x > (comets[j].x - comets[j].boundx) &&
bullet[i].x < (comets[j].x + comets[j].boundx) &&
bullet[i].y > (comets[j].y - comets[j].boundy) &&
bullet[i].y < (comets[j].y + comets[j].boundy))
{
bullet[i].live = false;
comets[j].live = false;
ship.score++;
StartExplosions(explosions, eSize, bullet[i].x, bullet[i].y);
al_play_sample(boom, 1, 0, 1, ALLEGRO_PLAYMODE_ONCE, 0);
}
}
}
}
}
}
void InitComet(Comet comets[], int size, ALLEGRO_BITMAP *image = NULL)
{
for(int i = 0; i < size; i++)
{
comets[i].ID = ENEMY;
comets[i].live = false;
comets[i].speed = 5;
comets[i].boundx = 35;
comets[i].boundy = 35;
comets[i].maxFrame = 143;
comets[i].curFrame = 0;
comets[i].frameCount = 0;
comets[i].frameDelay = 2;
comets[i].frameWidth = 96;
comets[i].frameHeight = 96;
comets[i].animationColumns = 21;
if(rand() % 2)
comets[i].animationDirection = 1;
else
comets[i].animationDirection = -1;
if(image != NULL)
comets[i].image = image;
}
}
void DrawComet(Comet comets[], int size)
{
for(int i = 0; i < size; i++)
{
if(comets[i].live)
{
int fx = (comets[i].curFrame % comets[i].animationColumns) * comets[i].frameWidth;
int fy = (comets[i].curFrame / comets[i].animationColumns) * comets[i].frameHeight;
al_draw_bitmap_region(comets[i].image, fx, fy, comets[i].frameWidth,
comets[i].frameHeight, comets[i].x - comets[i].frameWidth / 2, comets[i].y - comets[i].frameHeight / 2, 0);
/*al_draw_filled_rectangle(comets[i].x - comets[i].boundx, comets[i].y - comets[i].boundy, comets[i].x + comets[i].boundx,
comets[i].y + comets[i].boundy, al_map_rgba(255, 0, 255, 100));*/
}
}
}
void StartComet(Comet comets[], int size)
{
for(int i = 0; i < size; i++)
{
if(!comets[i].live)
{
if(rand() % 500 == 0)
{
comets[i].live = true;
comets[i].x = WIDTH;
comets[i].y = 30 + rand() % (HEIGHT - 60);
break;
}
}
}
}
void UpdateComet(Comet comets[], int size)
{
for(int i = 0; i < size; i++)
{
if(comets[i].live)
{
if(++comets[i].frameCount >= comets[i].frameDelay)
{
comets[i].curFrame += comets[i].animationDirection;
if(comets[i].curFrame >= comets[i].maxFrame)
comets[i].curFrame = 0;
else if( comets[i].curFrame <= 0)
comets[i].curFrame = comets[i].maxFrame - 1;
comets[i].frameCount = 0;
}
comets[i].x -= comets[i].speed;
}
}
}
void CollideComet(Comet comets[], int cSize, SpaceShip &ship, Explosion explosions[], int eSize)
{
for(int i = 0; i < cSize; i++)
{
if(comets[i].live)
{
if(comets[i].x - comets[i].boundx < ship.x + ship.boundx &&
comets[i].x + comets[i].boundx > ship.x - ship.boundx &&
comets[i].y - comets[i].boundy < ship.y + ship.boundy &&
comets[i].y + comets[i].boundy > ship.y - ship.boundy)
{
ship.lives--;
comets[i].live = false;
StartExplosions(explosions, eSize, ship.x, ship.y);
al_play_sample(boom, 1, 0, 1, ALLEGRO_PLAYMODE_ONCE, 0);
}
else if(comets[i].x < 0)
{
comets[i].live = false;
ship.lives--;
}
}
}
}
void InitExplosions(Explosion explosions[], int size, ALLEGRO_BITMAP *image = NULL)
{
for(int i = 0; i < size; i++)
{
explosions[i].live = false;
explosions[i].maxFrame = 31;
explosions[i].curFrame = 0;
explosions[i].frameCount = 0;
explosions[i].frameDelay = 1;
explosions[i].frameWidth = 128;
explosions[i].frameHeight = 128;
explosions[i].animationColumns = 8;
explosions[i].animationDirection = 1;
if(image != NULL)
explosions[i].image = image;
}
}
void DrawExplosions(Explosion explosions[], int size)
{
for(int i = 0; i < size; i++)
{
if(explosions[i].live)
{
int fx = (explosions[i].curFrame % explosions[i].animationColumns) * explosions[i].frameWidth;
int fy = (explosions[i].curFrame / explosions[i].animationColumns) * explosions[i].frameHeight;
al_draw_bitmap_region(explosions[i].image, fx, fy, explosions[i].frameWidth,
explosions[i].frameHeight, explosions[i].x - explosions[i].frameWidth / 2, explosions[i].y - explosions[i].frameHeight / 2, 0);
}
}
}
void StartExplosions(Explosion explosions[], int size, int x, int y)
{
for(int i = 0; i < size; i++)
{
if(!explosions[i].live)
{
explosions[i].live = true;
explosions[i].x = x;
explosions[i].y = y;
break;
}
}
}
void UpdateExplosions(Explosion explosions[], int size)
{
for(int i = 0; i < size; i++)
{
if(explosions[i].live)
{
if(++explosions[i].frameCount >= explosions[i].frameDelay)
{
explosions[i].curFrame += explosions[i].animationDirection;
if(explosions[i].curFrame >= explosions[i].maxFrame)
{
explosions[i].curFrame = 0;
explosions[i].live = false;
}
explosions[i].frameCount = 0;
}
}
}
}
void InitBackground(Background &back, float x, float y, float velx, float vely, int width, int height, int dirX, int dirY, ALLEGRO_BITMAP *image)
{
back.x = x;
back.y = y;
back.velX = velx;
back.velY = vely;
back.width = width;
back.height = height;
back.dirX = dirX;
back.dirY = dirY;
back.image = image;
}
void UpdateBackground(Background &back)
{
back.x += back.velX * back.dirX;
if(back.x + back.width <= 0)
back.x = 0;
}
void DrawBackground(Background &back)
{
al_draw_bitmap(back.image, back.x, back.y, 0);
if(back.x + back.width < WIDTH)
al_draw_bitmap(back.image, back.x + back.width, back.y, 0);
}
void ChangeState(int &state, int newState)
{
if(state == TITLE)
{}
else if(state == PLAYING)
{
al_stop_sample_instance(songInstance);
}
else if(state == LOST)
{}
state = newState;
if(state == TITLE)
{}
else if(state == PLAYING)
{
InitShip(ship);
InitBullet(bullets, NUM_BULLETS);
InitComet(comets, NUM_COMETS);
InitExplosions(explosions, NUM_EXPLOSIONS);
al_play_sample_instance(songInstance);
}
else if(state == LOST)
{}
}
