main_src.js

frame = 0;
GAME_STATE_WAIT = 0;
GAME_STATE_GAMEOVER = 1;
GAME_STATE_PLAY = 2;
gameState = 0;
oldButtons = [0, 0, 0, 0];
debug = false;
render = true;
clearScreen = true;

#define SCREEN_W 320
#define SCREEN_H 200

ship = {
	x: screen.w / 2,
	y: screen.h / 2,
	dx: 0,
	dy: 0,
	angle: 0,
	alive: false,
	radius: 4,
	accel: 0.1,
	turnSpeed: 0.1,
	friction: 0.005
};

laserSound = LoadSample("laser.wav");
teleSound = LoadSample("tele.wav");
explosionSounds = [LoadSample("expl1.wav"), LoadSample("expl2.wav"), LoadSample("expl3.wav")];
laserBitmap = LoadBitmap("laser.pcx");
bulletSpritesheet = CreateSpriteSheet(laserBitmap, 25, 25);
shipSprite = CreateSpriteSheet(LoadBitmap("ship.pcx"), 25, 25);
asteroidSpritesheet = CreateSpriteSheet(LoadBitmap("asteroid.pcx"), 51, 54);
SetPalette(LastBitmapPalette());

bulletAnimSpeed = 3;
bulletLifetime = 45;
bulletSpeed = 5;
bulletRadius = 2;

asteroidScale = [1, 0.6, 0.35, 0.225];
asteroidAnimLength = asteroidSpritesheet.numberOfFrames / 2;
asteroidAnimSpeed = [4.5, 4, 3.5, 3];
asteroidSpeed = [1, 1.5, 1.75, 1.875];
asteroidRadius = [27, 27/2, 27/4, 27/8];

maxAsteroids = 10 * 8;
maxBullets = 3;
asteroids = [];
bullets = [];
asteroidSprites = new Int32Array(maxAsteroids * 6);
for(var i = 0; i < maxAsteroids * 6; i += 6) asteroidSprites[i + 2] = -1;
bulletSprites = new Int32Array(maxBullets * 4);
for(var i = 0; i < maxBullets * 4; i += 4) bulletSprites[i + 2] = -1;
bulletIndex = 0;
asteroidIndex = 0;

function PlayExplosion(){
	PlaySample(explosionSounds[Math.floor(explosionSounds.length * Math.random())], 175, 128, 900 + Math.random() * 100, 0);
}


#define Move(obj)	\
	obj.x += obj.dx;	\
	obj.y += obj.dy;	\
	if(obj.x < 0 - obj.radius) obj.x = SCREEN_W + obj.radius;	\
	if(obj.y < 0 - obj.radius) obj.y = SCREEN_H + obj.radius;	\
	if(obj.x > SCREEN_W + obj.radius) obj.x = 0 - obj.radius;	\
	if(obj.y > SCREEN_H + obj.radius) obj.y = 0 - obj.radius;


//#define Collision(a, b)	((a.x - b.x) * (a.x - b.x) + (a.y - b.y) * (a.y - b.y) < (a.radius + b.radius) * (a.radius + b.radius))
#define Collision(a, b)	(Math.abs(a.x - b.x) < (a.radius + b.radius) && Math.abs(a.y - b.y) < (a.radius + b.radius))

function XCompare(a, b){
	return (b.x + b.radius < a.x + a.radius) ? 1 : (b.x + b.radius == a.x + a.radius) ? 0 : -1;
}

function CreateAsteroid(g, x, y){
	var moveAngle = Math.random() * 999;
	var spd = 0.75 + Math.random() * 0.25;
	var a = {
		generation: g,
		x: x,
		y: y,
		dx: Math.cos(moveAngle) * asteroidSpeed[g] * spd,
		dy: Math.sin(moveAngle) * asteroidSpeed[g] * spd,
		angle: FloatToFix(Math.random() * 256),
		scale: FloatToFix(asteroidScale[g]),
		fScale: asteroidScale[g],
		flips: (Math.random() > 0.5 ? FLIP_V : 0) | (Math.random() > 0.5 ? FLIP_H : 0),
		time: Math.random() * 999,
		animSpeed: asteroidAnimSpeed[g],
		type: Math.random() > 0.5 ? 1 : 0,
		radius: asteroidRadius[g],
		spr: ((asteroidIndex++) % maxAsteroids) * 6
	};
	asteroidSprites[a.spr + 3] = a.angle;
	asteroidSprites[a.spr + 4] = a.scale;
	asteroidSprites[a.spr + 5] = a.flips;
	return a;
}

function SpawnAsteroid(){
	asteroids.push(CreateAsteroid(0, Math.random() * screen.w, Math.random() * screen.h));
}


function DestroyShip(){
	if(!ship.alive) return;
	PlayExplosion();
	ship.alive = false;
}

function SpawnShip(){
	ship.alive = true;
	ship.x = screen.w / 2;
	ship.y = screen.h / 2;
	ship.dx = ship.dy = 0;
}


function SpawnBullet(){
	PlaySample(laserSound, 150, 128, 990 + Math.random() * 20, 0);
	var b;
	if(bullets.length >= maxBullets) bullets.shift();
	bullets.push(b = {
		x: ship.x,
		y: ship.y,
		time: 0,
		dx: Math.cos(ship.angle) * bulletSpeed,
		dy: Math.sin(ship.angle) * bulletSpeed,
		angle: FloatToFix(256 * ship.angle / (Math.PI * 2)),
		radius: bulletRadius,
		spr: ((bulletIndex++) % maxBullets) * 4
	});
	bulletSprites[b.spr + 3] = b.angle;
}


function DrawCircle(obj){
	Circle(screen, obj.x, obj.y, obj.radius, 1 + Math.random() * 254);
}

//#define GRID_COLLISION 1
//#define SORT_COLLISION 1
#define BROAD_COLLISION 1

#ifdef SORT_COLLISION
#define SORT_ASTEROIDS() asteroids = asteroids.sort(XCompare)
#else
#define SORT_ASTEROIDS()
#endif

#ifdef GRID_COLLISION
#define AST_PUTINGRID(a, i) asteroidCollision[Math.abs(a.x) >> 5].push(i); asteroidCollision[Math.abs(a.x - a.radius) >> 5].push(i); asteroidCollision[Math.abs(a.x + a.radius) >> 5].push(i);
#define CLEAR_GRID()	asteroidCollision = [[], [], [], [], [], [], [], [], [], [], [], [], [], []];
#else
#define AST_PUTINGRID(a, i)
#define CLEAR_GRID()
#endif

#ifdef BROAD_COLLISION
#define BROADPHASE_COLL(a, b) ((3584 >> (a.x >= 0 ? (a.x >> 5) : 0)) & (1024 >> (b.x >= 0 ? (b.x >> 5) : 0)))
#else
#define BROADPHASE_COLL(a, b) 1
#endif

function DestroyAsteroid(i, a){
	asteroidSprites[a.spr + 2] = -1;
	PlayExplosion();
	if(a.generation < 3){
		asteroids[i] = CreateAsteroid(a.generation + 1, a.x, a.y);
		asteroids.push(CreateAsteroid(a.generation + 1, a.x, a.y));
	}
	else{
		asteroids[i] = asteroids[asteroids.length - 1];
		asteroids[asteroids.length - 1] = a;
		asteroids.pop();
	}
	SORT_ASTEROIDS();
}

CLEAR_GRID();

function Loop(){
	frame++;
	if(asteroids.length == 0){
		SpawnAsteroid();
		SpawnAsteroid();
		SpawnAsteroid();
		asteroids = asteroids.sort(XCompare);
	}
	//UpdateShip();
		if(!ship.alive){
			if(buttons[0] & BUTTON_START) SpawnShip();
			ship.frame = 1;
		}
		else {
			if(buttons[0] & (~oldButtons[0]) & BUTTON_A){
				SpawnBullet();
			}
			if(buttons[0] & (~oldButtons[0]) & BUTTON_B){
				PlaySample(teleSound, 160, 128, 1000, 0);
				ship.x = Math.random() * screen.w;
				ship.y = Math.random() * screen.h;
			}
			
			ship.frame = 0;
			ship.dx -= Math.cos(ship.angle) * dpad[0].y * ship.accel;
			ship.dy -= Math.sin(ship.angle) * dpad[0].y * ship.accel;
			ship.dx -= ship.dx * ship.friction;
			ship.dy -= ship.dy * ship.friction;
			ship.angle += dpad[0].x * ship.turnSpeed;
			Move(ship);
		}
	//UpdateBullets();
		var numBullets = bullets.length;
		for(var i = 0; i < numBullets; i++){
			var b = bullets[i];
			
			Move(b);
			
			b.time++;
			if(b.time > bulletLifetime) b.dead = true;
			
			#ifdef SORT_COLLISION
			var j;
			for(j = 0; j < asteroids.length; j++){
				if(asteroids[j].x + asteroids[j].radius >= b.x - b.radius) break;
			}
			for(; j < asteroids.length; j++){
				if(asteroids[j].x - asteroids[j].radius > b.x + b.radius) break;
				var a = asteroids[j];
				if(Collision(b, a)){
					DestroyAsteroid(j, asteroids[j]);
					b.dead = true;
					break;
				}
			}
			#elif GRID_COLLISION
			if(1)
			{
				var k = Math.abs(b.x) >> 5;
				for(var j = 0; j < asteroidCollision[k].length; j++){
					var ai = asteroidCollision[k][j];
					var a = asteroids[ai];
					if(Collision(b, a)){
						DestroyAsteroid(ai, a);
						b.dead = true;
						break;
					}
				}
			}
			#else
			var numAsteroids = asteroids.length;
			for(j = 0; j < asteroids.length; j++){
				var a = asteroids[j];
				if(BROADPHASE_COLL(a, b) && Collision(b, a)){
					DestroyAsteroid(j, a);
					b.dead = true;
					break;
				}
			}
			#endif
			
			bulletSprites[b.spr + 0] = b.x - bulletSpritesheet.width * 0.5;
			bulletSprites[b.spr + 1] = b.y - bulletSpritesheet.height * 0.5;
			bulletSprites[b.spr + 2] = 0;
			
			if(b.dead){
				bulletSprites[b.spr + 2] = -1;
				bullets[i] = bullets[bullets.length - 1];
				bullets.pop();
				numBullets--;
			}
		}
	//UpdateAsteroids();
		CLEAR_GRID();
		var numAsteroids = asteroids.length;
		var oA = false;
		for(var i = 0; i < numAsteroids; i++){
			var a = asteroids[i];
			
			Move(a);
			
			if(Collision(a, ship)){
				DestroyShip();
			}
			
			asteroidSprites[a.spr + 0] = a.x - asteroidSpritesheet.width * a.fScale * 0.5;
			asteroidSprites[a.spr + 1] = a.y - asteroidSpritesheet.height * a.fScale * 0.5;
			asteroidSprites[a.spr + 2] = (((frame / a.animSpeed) % asteroidAnimLength) | 0) + asteroidAnimLength * a.type;
			
			AST_PUTINGRID(a, i);
			/*
			if(oA && (oA.x + oA.radius > a.x + a.radius)){
				asteroids[i] = oA;
				asteroids[i - 1] = a;
			}
			oA = a;
			*/
		}
		SORT_ASTEROIDS();
	
	if(clearScreen) ClearToColor(screen, 1);
	if(render){
		DrawSpriteBatch(screen, asteroidSpritesheet, SPRITE_ROTATE | SPRITE_SCALE | SPRITE_FLIP, asteroidSprites.subarray(0, asteroidIndex * 6));
		if(bulletIndex) DrawSpriteBatch(screen, bulletSpritesheet, SPRITE_ROTATE, bulletSprites.subarray(0, bulletIndex * 4));
		DrawTransformSprite(screen, shipSprite, SPRITE_ROTATE, ship.x - 12.5, ship.y - 12.5, ship.frame, FloatToFix(256 * ship.angle / (Math.PI * 2)));
	}
	
	if(debug || !render){
		var stuff = bullets.concat(asteroids);
		stuff.forEach(DrawCircle);
		Triangle(screen, ship.x + Math.cos(ship.angle) * 8, ship.y + Math.sin(ship.angle) * 8, ship.x + Math.cos(ship.angle - 2.5) * 5, ship.y + Math.sin(ship.angle - 2.5) * 5, ship.x + Math.cos(ship.angle + 2.5) * 5, ship.y + Math.sin(ship.angle + 2.5) * 5, 1 + Math.random() * 254);
	}
	TextOut(screen, "FPS: " + fps, 0, 0, 128);
	oldButtons = buttons.slice();
}