// SslbParser // Sslb (Shmup Specific Language:Bullet) parser. // <Operation> // Mouse: Move your ship. package { import flash.display.Sprite; [SWF(width="465", height="465", backgroundColor="0", frameRate="30")] public class Main extends Sprite { public function Main() { main = this; initialize(); } } } import flash.display.*; import flash.filters.*; import flash.geom.*; import flash.events.*; import flash.text.*; import org.si.sion.*; import org.si.sion.utils.*; const SCREEN_WIDTH:int = 465, SCREEN_HEIGHT:int = 465; var sslbRoot:String = (<![CDATA[ nway 1..12 30__90 nwayslide $1 $2 0 nwayslide 1..12 10__90 0.2__0.5 fire -$2 -$3 repeat $1 fire $2*2/$1 $3*2/($1-1) nwayturn 1..12 30__90*-1|1 1..6 fire -$2 repeat $1 wait $3 fire $2*2/$1 nwayturncenter 1..12 30__120*-1|1 1..6 fire repeat $1 wait $3 fire $2/$1 nwayturntoandfrom 1..12 30__120*-1|1 1..6 fire -$2 repeat $1 wait $3 fire $2*2/$1 repeat $1 wait $3 fire -$2*2/$1 wedge 1..6 30__120 0.2__0.5*-1|1 fire -$2 -$3 repeat $1 fire $2/$1 $3*2/$1 repeat $1 fire $2/$1 -$3*2/$1 round 3..32 repeat $1 fire 360/$1 roundturn 3..32 1..4 -1|1 fire repeat $1 wait $2 fire 360/$1*$3 ]]>).toString(); var sslbBranch:String = (<![CDATA[ bar 2..6 3..8 speed 0 whip $1 $2 whip 2..6 3..8 0.2__0.6 fire 0 -$3 repeat $1 wait $2 fire 0 $3*2/$1 shotside 3..12 fire 90 vanish repeat inf wait $1 fire 180 fire 180 shotaim 3..12 repeat inf wait $1 fireaim 0 shotslow 3..12 wait $1 fire 0 -0.5 repeat inf wait $1 fire changespeed 0.4__0.8*-1|1 5..30 speed 1+$1 $2 curve 2__10*-1|1 20..60 angvel $1 $2 ]]>).toString(); var main:Main, stage:Stage, screen:BitmapData; var point:Point = new Point; var commands:Array = new Array; var rootCommands:Vector.<Command> = new Vector.<Command>; var branchCommands:Vector.<Command> = new Vector.<Command>; var sslbTextField:TextField; var driver:SiONDriver = new SiONDriver(); var percusVoices:Array = new SiONPresetVoice()["valsound.percus"]; var drum1:SiONData, drum2:SiONData, drum3:SiONData; // Initialize. function initialize():void { stage = main.stage; var sslbXmls:Vector.<XML>; sslbXmls = parseIndentedText(sslbRoot); for each (var sslb:XML in sslbXmls) { var c:Command = new Command(sslb); commands[c.name] = c; rootCommands.push(c); branchCommands.push(c); } sslbXmls = parseIndentedText(sslbBranch); for each (sslb in sslbXmls) { c = new Command(sslb); commands[c.name] = c; branchCommands.push(c); } Bullet.initialize(); drum1 = createDrum(14); drum2 = createDrum(27); drum3 = createDrum(0); screen = new BitmapData(SCREEN_WIDTH, SCREEN_HEIGHT, false); sslbTextField = createTextField(0, 0, SCREEN_WIDTH / 2, SCREEN_HEIGHT, 0xffffff); main.addChild(new Bitmap(screen)); main.addChild(sslbTextField); main.addEventListener(Event.ENTER_FRAME, update); } // Update the frame. const MAX_SSLB_COUNT:int = 2; var ticks:int = 0; var rootCommand:Command; var addCommandFlags:Vector.<Boolean> = new Vector.<Boolean>(MAX_SSLB_COUNT), childCommands:Vector.<Command>; function update(event:Event):void { var t:int = ticks % 60; if (t == 0) { rootCommand = rootCommands[randi(rootCommands.length)]; childCommands = new Vector.<Command>; for (var i:int = 0; i < MAX_SSLB_COUNT; i++) addCommandFlags[i] = (randi(2) == 0); sslbTextField.text = rootCommand.toString(); driver.play(drum1); } else if (t % 7 == 0) { var at:int = t / 7 - 1; if (at < MAX_SSLB_COUNT && addCommandFlags[at]) { var c:Command = branchCommands[randi(branchCommands.length)].getRandomFixedClone(); childCommands.push(c); sslbTextField.appendText(c.toString()); driver.play(drum3); } } else if (t % 60 == 30) { var p:Vector3D = new Vector3D(SCREEN_WIDTH / 2, SCREEN_HEIGHT * 0.2); var a:Number; if (randi(2) == 0) a = getPlayerAngle(p); else a = randn(PI) - PI / 2; addBullet(p, a, 5, true, rootCommand, null, childCommands); driver.play(drum2); } ticks++; for (i = 0; i < bullets.length; i++) if (!bullets[i].update()) { bullets.splice(i, 1); i--; } if (bullets.length >= MAX_BULLET_COUNT) bullets.splice(MAX_BULLET_COUNT, bullets.length - MAX_BULLET_COUNT); screen.lock(); screen.fillRect(screen.rect, 0); for each (var b:Bullet in bullets) b.drawBlur(); player.update(); for each (b in bullets) b.draw(); screen.unlock(); } // Player. var player:Player = new Player; class Player { private const HIT_RANGE:Number = 5; public var pos:Vector3D = new Vector3D; private var bd:BitmapData, bdRect:Rectangle; private var invincibleTicks:int = 60; public function Player() { pos.x = SCREEN_WIDTH / 2; pos.y = SCREEN_HEIGHT * 0.75; bd = createCircleBitmapData(12, 0x88, 0xff, 0xcc, 0.8, 3, 7); bdRect = bd.rect; } public function update():void { pos.x += (stage.mouseX - pos.x) * 0.2; pos.y += (stage.mouseY - pos.y) * 0.2; point.x = pos.x - bdRect.width / 2; point.y = pos.y - bdRect.height / 2; if (invincibleTicks >= 0) { invincibleTicks--; if (invincibleTicks % 15 < 7) return; } screen.copyPixels(bd, bdRect, point); } public function checkHit(p:Vector3D):void { if (invincibleTicks < 0 && Vector3D.distance(pos, p) < HIT_RANGE) { invincibleTicks = 60; for (var i:int = 0; i < 64; i++) { bullets.push(new Bullet(pos, randn(PI * 2), randn(10) + 10, false, null, null, null, true)); } } } } function getPlayerAngle(p:Vector3D):Number { return atan2(player.pos.x - p.x, player.pos.y - p.y); } // Bullets. const MAX_BULLET_COUNT:int = 256, MAX_TICKS:int = 30 * 5; var bullets:Vector.<Bullet> = new Vector.<Bullet>; class Bullet { private static var bd:BitmapData, bdRect:Rectangle; private static var fragmentBd:BitmapData, fragmentBdRect:Rectangle; private static var blurBds:Vector.<BitmapData> = new Vector.<BitmapData>; private static var blurRects:Vector.<Rectangle> = new Vector.<Rectangle>; private static const BLUR_SIZE_COUNT:int = 7, BLUR_COLOR_COUNT:int = 8; public var pos:Vector3D; public var angle:Number, speed:Number; public var runState:RunState; public var isRemoving:Boolean; public var childCommands:Vector.<Command>; private var isRoot:Boolean, ticks:int; private var isFragment:Boolean; public static function initialize():void { bd = createCircleBitmapData(10, 0xaa, 0x77, 0xdd, 0.75, 1, 8); bdRect = bd.rect; fragmentBd = createCircleBitmapData(8, 0xdd, 0xcc, 0x66, 0.5, 8, 4); fragmentBdRect = fragmentBd.rect; bdRect = bd.rect; for (var i:int = 0; i < BLUR_SIZE_COUNT; i++) { var radius:Number = (BLUR_SIZE_COUNT - i) * 2, a:Number = 0.5 - i * 0.05; for (var j:int = 0; j < BLUR_COLOR_COUNT; j++) { var r:int = 0xff - j * 0x11; var b:int = 0x88; var bbd:BitmapData = createCircleBitmapData(radius, r, 0, b, a, 5); blurBds.push(bbd); blurRects.push(bbd.rect); } } } public function Bullet(p:Vector3D, angle:Number, speed:Number, isRoot:Boolean, command:Command, vars:Vector.<Number>, ccs:Vector.<Command>, isFragment:Boolean = false) { pos = new Vector3D(p.x, p.y); this.angle = angle; this.speed = speed; this.isRoot = isRoot; this.isFragment = isFragment; if (command == null && ccs != null && ccs.length > 0) { command = ccs[0]; childCommands = new Vector.<Command>; for (var i:int = 1; i < ccs.length; i++) childCommands.push(ccs[i]); vars = null; isRoot = true; } else { childCommands = ccs; } if (command != null) runState = new RunState(this, command, vars); } public function update():Boolean { if (runState != null) { if (!runState.isEnded) runState.update(); else if (isRoot) return false; if (isRemoving) return false; } if (!isRoot) { pos.x += sin(angle) * speed; pos.y += cos(angle) * speed; player.checkHit(pos); } ticks++; return (pos.x >= 0 && pos.x <= SCREEN_WIDTH && pos.y >= 0 && pos.y <= SCREEN_HEIGHT && ticks < MAX_TICKS); } public function draw():void { if (isRoot) return; if (!isFragment) { point.x = pos.x - bdRect.width / 2; point.y = pos.y - bdRect.height / 2; screen.copyPixels(bd, bdRect, point); } else { point.x = pos.x - fragmentBdRect.width / 2; point.y = pos.y - fragmentBdRect.height / 2; screen.copyPixels(fragmentBd, fragmentBdRect, point); } } public function drawBlur():void { if (isRoot || isFragment) return; var px:Number = pos.x, py:Number = pos.y; var vx:Number = sin(angle) * speed * 2; var vy:Number = cos(angle) * speed * 2; var t:int = ticks; for (var i:int = 0; i < BLUR_SIZE_COUNT; i++) { if (t-- <= 0) break; var c:int = t % (BLUR_COLOR_COUNT * 2); if (c >= BLUR_COLOR_COUNT) c = BLUR_COLOR_COUNT * 2 - c - 1; var bi:int = c + i * BLUR_COLOR_COUNT; point.x = px - blurRects[bi].width / 2; point.y = py - blurRects[bi].height / 2; screen.copyPixels(blurBds[bi], blurRects[bi], point); px -= vx; py -= vy; } } } function addBullet(p:Vector3D, angle:Number, speed:Number, isRoot:Boolean, command:Command, vars:Vector.<Number>, ccs:Vector.<Command>):void { bullets.push(new Bullet(p, angle, speed, isRoot, command, vars, ccs)); } // Sslb run state. class RunState { public var bullet:Bullet; public var fireAngle:Number, fireSpeed:Number, fireBaseSpeed:Number; public var speedVel:Number, speedVelTicks:int; public var angVel:Number, angVelTicks:int; public var waitTicks:int; private var states:Vector.<ScopeState> = new Vector.<ScopeState>; private var current:ScopeState; public function RunState(bullet:Bullet, root:Command, vars:Vector.<Number>) { this.bullet = bullet; fireAngle = bullet.angle; fireSpeed = fireBaseSpeed = bullet.speed; current = new ScopeState(root, vars, 1, this); } public function update():void { if (speedVelTicks > 0) { bullet.speed += speedVel; speedVelTicks--; } if (angVelTicks > 0) { bullet.angle += angVel; angVelTicks--; } if (waitTicks > 0) { waitTicks--; return; } if (current != null) current.update(); } public function pushCurrent(newState:ScopeState):void { states.push(current); current = newState; update(); } public function popCurrent():void { if (states.length <= 0) { current = null; return; } current = states.pop(); update(); } public function get isEnded():Boolean { return current == null && speedVelTicks <= 0 && angVelTicks <= 0; } } class ScopeState { private var runState:RunState, bullet:Bullet; private var command:Command; private var vars:Vector.<Number> = new Vector.<Number>; private var programCount:int, repeatCount:int; public function ScopeState(command:Command, vs:Vector.<Number>, repeatCount:int, runState:RunState) { this.runState = runState; bullet = runState.bullet; this.command = command; this.repeatCount = repeatCount; var vc:int = 0; if (vs != null) { for each (var v:Number in vs) { vars.push(v); vc++; } } for (var i:int = vc; i < command.args.length; i++) vars.push(command.args[i].calc(vars)); } public function update():void { if (programCount >= command.children.length) { repeatCount--; if (repeatCount <= 0) { runState.popCurrent(); return; } else { programCount = 0; } } var c:Command = command.children[programCount]; programCount++; var cn:String = c.name; if (cn == "fire" || cn == "fireaim") { if (bullet.pos.y < SCREEN_HEIGHT / 2) { var al:int = c.args.length; if (al > 0) { if (cn == "fire") runState.fireAngle += c.args[0].calc(vars) * PI / 180; else runState.fireAngle = getPlayerAngle(bullet.pos) + c.args[0].calc(vars) * PI / 180; } if (al > 1) runState.fireSpeed += runState.fireBaseSpeed * c.args[1].calc(vars); var command:Command; if (c.children.length > 0) command = c; addBullet(bullet.pos, runState.fireAngle, runState.fireSpeed, false, command, vars, bullet.childCommands); } } else if (cn == "repeat") { runState.pushCurrent(new ScopeState(c, vars, c.args[0].calc(vars), runState)); return; } else if (cn == "wait") { runState.waitTicks = c.args[0].calc(vars); if (runState.waitTicks > 0) return; } else if (cn == "vanish") { if (c.args.length <= 0 || c.args[0].calc(vars) <= 0) bullet.isRemoving = true; } else if (cn == "angvel") { runState.angVel = c.args[0].calc(vars) * PI / 180; if (c.args.length > 1) runState.angVelTicks = c.args[1].calc(vars); else runState.angVelTicks = 9999999; } else if (cn == "speed") { var ts:Number = c.args[0].calc(vars); var t:int = 1; if (c.args.length > 1) t = c.args[1].calc(vars); runState.speedVel = bullet.speed * (ts - 1) / t; runState.speedVelTicks = t; } else { var vs:Vector.<Number> = new Vector.<Number>; for each (var arg:Expression in c.args) vs.push(arg.calc(vars)); runState.pushCurrent(new ScopeState(commands[cn], vs, 1, runState)); return; } update(); } } // Sslb command. class Command { public var name:String; public var args:Vector.<Expression> = new Vector.<Expression>; public var children:Vector.<Command> = new Vector.<Command>; public var value:XML; public function Command(v:XML) { value = v; name = v.name(); for each (var a:String in v._arg) args.push(new Expression(a)); if (v._line.length() >= 1) for each (var l:XML in v._line[0].children()) children.push(new Command(l)); } public function getRandomFixedClone():Command { var c:Command = new Command(value); c.fixRandom(); return c; } public function fixRandom():void { for each (var a:Expression in args) a.fixRandom(); for each (var c:Command in children) c.fixRandom(); } public function toString(indent:int = 0):String { var s:String = ""; for (var i:int = 0; i < indent; i++) s += " "; s += name + " "; for each (var a:Expression in args) s += a.str + " "; s += "\n"; for each (var c:Command in children) s += c.toString(indent + 1); return s; } } // Expression. class Expression { private static const PLUS:int = -1, MINUS:int = -2, MULTIPLE:int = -3, DIVISION:int = -4, MODULO:int = -5; private static const INT_RAND:int = -6, NUMBER_RAND:int = -7, OR_RAND:int = -8, VARIABLE:int = -9; public var str:String; private var operator:Vector.<int> = new Vector.<int>; private var value:Vector.<Number> = new Vector.<Number>; public function Expression(s:String) { str = s; removeWhiteSpace(); parseToRPN(0, str.length); } public function calc(vars:Vector.<Number>):Number { var stack:Vector.<Number> = new Vector.<Number>; for each (var op:int in operator) { if (op >= 0) { stack.push(value[op]); } else if (op <= VARIABLE) { stack.push(vars[VARIABLE - op]); } else { switch(op) { case PLUS: case MINUS: case MULTIPLE: case DIVISION: case MODULO: case INT_RAND: case NUMBER_RAND: case OR_RAND: var n1:Number = stack.pop(); var n2:Number = stack.pop(); stack.push(calcOperator(op, n2, n1)); break; default: throw new Error("illegal operator: " + op); } } } return stack.pop(); } public function fixRandom():void { for (var i:int = 0; i < operator.length; i++) { var op:int = operator[i]; if (op == INT_RAND || op == NUMBER_RAND || op == OR_RAND) { var i1:int = operator[i - 1]; var i2:int = operator[i - 2]; if (i1 >= 0 && i2 >= 0) { var n1:Number = value[i1]; var n2:Number = value[i2]; var ni:int = value.push(calcOperator(op, n1, n2)) - 1; i -= 2; operator[i] = ni; operator.splice(i + 1, 2); } } } } private function removeWhiteSpace():void { var cs:String = new String; var skip:Boolean = false; var depth:int = 0; for (var i:int = 0; i < str.length; i++) { switch (str.charAt(i)) { case ' ': case '\n': case '\r': skip = true; break; case ')': depth--; if ( depth < 0 ) throw new Error("bracket not match"); break; case '(': depth++; break; } if (skip) skip = false; else cs += str.charAt(i); } if (depth != 0) throw new Error("bracket not match"); str = cs; } private function parseToRPN(stIdx:int, edIdx:int):void { var op0:int = -1, op1:int = -1, op2:int = -1; for (var i:int = edIdx - 1; i >= stIdx; i--) { var c:String = str.charAt(i); if (c == ')') { var bc:int = 1; do { i--; if (str.charAt(i) == ')') bc++; else if (str.charAt(i) == '(') bc--; } while (bc > 0); } else if (op0 < 0 && (c == '.' || c == '_' || c == '|')) { if (c == '.' || c == '_') { var c2:String = str.charAt(i - 1); if ((c == '.' && c2 != '.') || (c == '_' && c2 != '_')) continue; i--; } op0 = i; } else if (op1 < 0 && (c == '*' || c == '/' || c == '%')) { op1 = i; } else if (op2 < 0 && (c == '+' || c == '-')) { op2 = i; } } if (op0 < 0 && op1 < 0 && op2 < 0 && str.charAt(stIdx) == '(' && str.charAt(edIdx - 1) == ')') { parseToRPN(stIdx + 1, edIdx - 1); return; } if (op2 == stIdx) { if (op0 < 0 && op1 < 0) { switch (str.charAt(op2)) { case '-': parseToRPN(stIdx + 1, edIdx); pushNumber(-1); pushOperator(MULTIPLE); break; case '+': parseToRPN(stIdx + 1, edIdx); break; default: throw new Error("unknown unary operator: " + str.charAt(op2)); } return; } else { op2 = -1; } } if (op2 >= 0) { c = str.charAt(op2 - 1); if (c == '+' || c == '-' || c == '*' || c == '/' || c == '%' || c == '.' || c == '_' || c == '|') op2 = -1; } if (op2 < 0) { if (op1 < 0) { if (op0 < 0) { parseFloatValue(stIdx, edIdx - stIdx); } else { parseToRPN(stIdx, op0); var ni:int = 1; c = str.charAt(op0); if (c == '.' || c =='_') ni = 2; parseToRPN(op0 + ni, edIdx); switch(c) { case '.': operator.push(INT_RAND); break; case '_': operator.push(NUMBER_RAND); break; case '|': operator.push(OR_RAND); break; default: throw new Error("unknown operator: " + str.charAt(op0)); } } } else { parseToRPN(stIdx, op1); c = str.charAt(op1); parseToRPN(op1 + 1, edIdx); switch(c) { case '*': pushOperator(MULTIPLE); break; case '/': pushOperator(DIVISION); break; case '%': pushOperator(MODULO); break; default: throw new Error("unknown operator: " + str.charAt(op1)); } } } else { parseToRPN(stIdx, op2); parseToRPN(op2 + 1, edIdx); switch(str.charAt(op2)) { case '+': pushOperator(PLUS); break; case '-': pushOperator(MINUS); break; default: throw new Error("unknown operator: " + str.charAt(op2)); } } } private function parseFloatValue(stIdx:int, lgt:int):void { if (str.charAt(stIdx) == '$') { var label:String = str.substr(stIdx + 1, lgt - 1); var nidx:Number = parseInt(label); if (isNaN(nidx)) throw new Error("illegal variable: $" + label); var idx:int = nidx; idx--; pushVariable(VARIABLE - idx); } else { var s:String = str.substr(stIdx, lgt); if (s == "inf") { pushNumber(9999999); } else { var v:Number = Number(s); if (isNaN(v)) throw new Error ("illegal number: " + str.substr(stIdx, lgt)); pushNumber(v); } } } private function pushOperator(op:int):void { var idx:int = operator.length; if (operator[idx - 2] >= 0 && operator[idx - 1] >= 0) { var i1:int = operator.pop(); var i2:int = operator.pop(); var n1:Number = value[i1]; var n2:Number = value[i2]; if (i1 > i2) { value.splice(i1, 1); value.splice(i2, 1); } else { value.splice(i2, 1); value.splice(i1, 1); } var ni:int = value.push(calcOperator(op, n2, n1)) - 1; operator.push(ni); } else { operator.push(op); } } private function pushVariable(vi:int):void { operator.push(vi); } private function pushNumber(n:Number):void { var ni:int = value.push(n) - 1; operator.push(ni); } private function calcOperator(op:int, n1:Number, n2:Number):Number { switch (op) { case PLUS: return n1 + n2; case MINUS: return n1 - n2; case MULTIPLE: return n1 * n2; case DIVISION: return n1 / n2; case MODULO: return n1 % n2; case INT_RAND: return randi(n2 - n1) + n1; case NUMBER_RAND: return randn(n2 - n1) + n1; case OR_RAND: return (randi(2) == 0 ? n1 : n2); default: throw new Error("illegal operator: " + op); } } } // Indented text parser. function parseIndentedText(s:String):Vector.<XML> { var indentSpaceCounts:Vector.<int> = new Vector.<int>; var indentSpaceCount:int = 0; var parentXmls:Vector.<XML> = new Vector.<XML>; indentSpaceCounts.push(indentSpaceCount); var lines:Array = s.split("\r\n").join("\n").split("\n"); var texts:Vector.<XML> = new Vector.<XML>; var parent:XML, current:XML; for each (var line:String in lines) { var l:String = trimStart(line); if (l.length <= 0) continue; var strs:Array = l.split(" "); var isc:int = line.length - l.length; if (isc > indentSpaceCount) { indentSpaceCounts.push(indentSpaceCount); indentSpaceCount = isc; parentXmls.push(parent); var lineXml:XML = new XML("<_line />"); current.appendChild(lineXml); parent = lineXml; } else if (isc < indentSpaceCount) { while (isc < indentSpaceCount) { indentSpaceCount = indentSpaceCounts.pop(); parent = parentXmls.pop(); } } if (parentXmls.length == 0 && parent != null) { texts.push(parent); parent = null; } current = new XML("<" + strs[0] + " />"); for (var i:int = 1; i < strs.length; i++) { current.appendChild(new XML("<_arg>" + strs[i] + "</_arg>")); } if (parent != null) parent.appendChild(current); else parent = current; } if (parentXmls.length > 0) texts.push(parentXmls[0]); return texts; } // Create a circle bitmap data. function createCircleBitmapData(radius:int, r:int, g:int, b:int, a:Number, blurSize:int, shineCount:int = 1):BitmapData { var s:Shape, gr:Graphics, bd:BitmapData; var blur:BlurFilter = new BlurFilter; blur.blurX = blur.blurY = blurSize; s = new Shape; gr = s.graphics; var p:Number = radius + blurSize, rd:int = radius; for (var i:int = 0; i < shineCount; i++) { gr.beginFill(r * 0x10000 + g * 0x100 + b, a); gr.drawCircle(p, p, rd); gr.endFill(); p += 0.5; rd -= 1; r += 0x10; if (r > 0xff) r = 0xff; g += 0x10; if (g > 0xff) g = 0xff; b += 0x10; if (b > 0xff) b = 0xff; } s.filters = [blur]; var sz:int = (radius + blurSize) * 2; bd = new BitmapData(sz, sz, true, 0); bd.draw(s); return bd; } // Utility functions. var sin:Function = Math.sin, cos:Function = Math.cos, atan2:Function = Math.atan2; var abs:Function = Math.abs, PI:Number = Math.PI; function createTextField(x:int, y:int, width:int, height:int, color:int):TextField { var fm:TextFormat = new TextFormat, fi:TextField = new TextField; fm.font = "_typewriter"; fm.bold = true; fm.size = 12; fm.color = color; fi.defaultTextFormat = fm; fi.x = x; fi.y = y; fi.width = width; fi.height = height; fi.selectable = false; return fi; } function createDrum(voiceNum:int):SiONData { var drum:SiONData = driver.compile("#EFFECT0{ws95lf4000}; %6@0o2v1c16"); drum.setVoice(0, percusVoices[voiceNum]); return drum; } function randi(n:int):int { return Math.random() * n; } function randn(n:Number):Number { return Math.random() * n; } function trimStart(s:String):String { if (s.charAt(0) == ' ') s = trimStart(s.substring(1)); return s; }