As3 programando jogos

Pra quem gosta de programação, a vontade de desenvolver um jogo sempre vem a mente. As vezes você navega e acha um jogo legal, achando impossível de desenvolver um desses.

Abaixo um exemplo de jogo, você tem que fazer a defesa de seu território colocando canhões em pontos estratégicos, impedindo que o inimigo atravesse o terreno. Eu particularmente acho esse jogo muito legal.

link do jogo: http://www.minijuegos.com/juegos/jugar.php?id=7929 

 

Olhando para esse jogo, você vai ter muitas dúvidas: como trilhar o caminho do inimigo, como fazer o canhão atirar no inimigo ou o hitTest para posicionar seus canhões em um campo pre-definido, essas e outras questões devem estar passando por sua cabeça.

No mesmo sentido do jogo acima, estou colocando um tutorial ensinando como fazer o motor básico desse jogo, com ele você pode criar diversos jogos, mesmo que não tenha interesse em criar um jogo, acho muito importante analisar e compreender o funcionamento.

Esse tutorial foi feito pelo pessoal da: flashgametuts.com estou somente espalhando.

Source: http://www.flashgametuts.com/obj/tuts/tower-defense-as3/pt7/tower-defense-as3-source.zip 

  1: var F:String = 'FINISH';

  2: var U:String = 'UP';

  3: var R:String = 'RIGHT';

  4: var D:String = 'DOWN';

  5: var L:String = 'LEFT';

  6:

  7: var startDir:String;//the direction the enemies go when they enter

  8: var finDir:String;//the direction the enemies go when they exit

  9: var startCoord:int;//the coordinates of the beginning of the road

 10: var lvlArray:Array = new Array();//this array will hold the formatting of the roads

 11:

 12: lvlArray = [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

 13: 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

 14: 0,0,0,0,R,1,1,D,0,0,R,1,1,D,0,0,R,1,1,D,0,0,

 15: 0,0,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,

 16: 0,0,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,

 17: S,D,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,R,1,F,

 18: 0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,0,0,0,

 19: 0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,1,0,0,0,0,0,

 20: 0,R,1,1,U,0,0,R,1,1,U,0,0,R,1,1,U,0,0,0,0,0,

 21: 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

 22: 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

 23: 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,

 24: ];

 25:

 26: //the names of these variables explain what they do

 27: var currentLvl:int = 1;

 28: var gameOver:Boolean = false;

 29:

 30: var currentEnemy:int = 0;//the current enemy that we're creating from the array

 31: var enemyTime:int = 0;//how many frames have elapsed since the last enemy was created

 32: var enemyLimit:int = 12;//how many frames are allowed before another enemy is created

 33: var enemyArray:Array = new Array();//this array will tell the function when to create an enemy

 34: var enemiesLeft:int;//how many enemies are left on the field

 35: enemyArray = [//defining the array

 36: [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1],//1's will just represent an enemy to be created

 37: [2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2],//another row means another level

 38: [3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3],

 39: [100],

 40: [5,6,7,6,5,6,7,6,5,6,7,6,5,6,7,6,5,6,7,6,5,6,7,6,5,6,7,6,5],

 41: [250,250,250]

 42:   ];

 43:

 44: var money:int=100;//how much money the player has to spend on turrets

 45: var lives:int=20;//how many lives the player has

 46:

 47: var rangeCircle:Shape = new Shape();

 48: rangeCircle.graphics.beginFill(0x006600,.5);

 49: rangeCircle.graphics.drawCircle(12.5,12.5,100);

 50: rangeCircle.graphics.endFill();

 51:

 52: function startGame():void{//we'll run this function every time a new level begins

 53: for(var i:int=0;i<enemyArray[currentLvl-1].length;i++){

 54: if(enemyArray[currentLvl-1][i] != 0){

 55: enemiesLeft ++;

 56: }

 57: }

 58: }

 59:

 60: var roadHolder:Sprite = new Sprite();//create an object that will hold all parts of the road

 61: addChild(roadHolder);//add it to the stage

 62: function makeRoad():void{

 63: var row:int = 0;//the current row we're working on

 64: var block;//this will act as the block that we're placing down

 65: for(var i:int=0;i<lvlArray.length;i++){//creating a loop that'll go through the level array

 66: if(lvlArray[i] == 0){//if the current index is set to 0

 67: block = new EmptyBlock();//create a gray empty block

 68: block.graphics.beginFill(0x333333);

 69: block.graphics.drawRect(0,0,25,25);

 70: block.graphics.endFill();

 71: addChild(block);

 72: //and set the coordinates to be relative to the place in the array

 73: block.x= (i-row*22)*25;

 74: block.y = row*25;

 75: } else if(lvlArray[i] == 1){//if there is supposed to be a row

 76: //just add a box that will be a darker color and won't have any actions

 77: block = new Shape();

 78: block.graphics.beginFill(0x111111);

 79: block.graphics.drawRect(0,0,25,25);

 80: block.graphics.endFill();

 81: block.x= (i-row*22)*25;

 82: block.y = row*25;

 83: roadHolder.addChild(block);//add it to the roadHolder

 84: } else if(lvlArray[i] is String){//if it's a string, meaning a special block

 85: //then create a special block

 86: block = new DirectBlock(lvlArray[i],(i-row*22)*25,row*25);

 87: addChild(block);

 88: }

 89: for(var c:int = 1;c<=16;c++){

 90: if(i == c*22-1){

 91: //if 22 columns have gone by, then we move onto the next row

 92: row++;

 93: }

 94: }

 95: }

 96: }

 97:

 98: function makeTurret(xValue:int,yValue:int):void{//this will need to be told the x and y values

 99: var turret:Turret = new Turret();//creating a variable to hold the Turret

100: //changing the coordinates

101: turret.x = xValue+12.5;

102: turret.y = yValue+12.5;

103: addChild(turret);//add it to the stage

104: }

105:

106: addEventListener(Event.ENTER_FRAME, eFrame);//adding an eFrame function

107: function eFrame(e:Event):void{

108: //if there aren't any levels left

109: if(currentLvl > enemyArray.length){

110: gameOver=true;//set the game to be over

111:

112: //reset all the stats

113: currentLvl = 1;

114: currentEnemy = 0;

115: enemyTime = 0;

116: enemyLimit = 12;

117: enemiesLeft = 0;

118:

119: removeEventListener(Event.ENTER_FRAME, eFrame);//remove this listener

120: removeChild(roadHolder);//remove the pieces of road

121: gotoAndStop('win');//go to the win frame

122: }

123: if(lives<=0){//if the user runs out of lives

124: gameOver=true;//set the game to be over

125:

126: //reset all the stats

127: currentLvl = 1;

128: currentEnemy = 0;

129: enemyTime = 0;

130: enemyLimit = 12;

131: enemiesLeft = 0;

132:

133: removeEventListener(Event.ENTER_FRAME, eFrame);//remove this listener

134: removeChild(roadHolder);//remove the pieces of road

135: gotoAndStop('lose');//go to the lose frame

136: }

137: makeEnemies();//we'll just make some enemies

138: if(enemiesLeft==0){//if there are no more enemies left

139: currentLvl ++;//continue to the next level

140: currentEnemy = 0;//reset the amount of enemies there are

141: startGame();//restart the game

142: }

143: //Updating the text fields

144: txtLevel.text = 'Level '+currentLvl;

145: txtMoney.text = '$'+money;

146: txtLives.text = 'Lives: '+lives;

147: txtEnemiesLeft.text = 'Enemies Left:  '+enemiesLeft;

148: }

149:

150: function makeEnemies():void{//this function will add enemies to the field

151: if(enemyTime < enemyLimit){//if it isn't time to make them yet

152: enemyTime ++;//then keep on waiting

153: } else {//otherwise

154: var theCode:int = enemyArray[currentLvl-1][currentEnemy];//get the code from the array

155: if(theCode != 0){//if it isn't an empty space

156: var newEnemy:Enemy = new Enemy(theCode);//then create a new enemy and pass in the code

157: enemyHolder.addChild(newEnemy);//and add it to the enemyholder

158: }

159: currentEnemy ++;//move on to the next enemy

160: enemyTime = 0;//and reset the time

161: }

162: }

163:

164: //run these functions at the start

165: makeRoad();

166: var enemyHolder:Sprite = new Sprite();

167: addChild(enemyHolder);

168: startGame();

Resultado final:

[flash http://www.flashgametuts.com/obj/tuts/tower-defense-as3/pt7/source.swf w=420 h=420]

No site do pessoal tem mais tutoriais legais, são simples, mas são o alicerce de qualquer jogo. Boa Sorte!