{"id":608,"date":"2008-08-23T08:01:19","date_gmt":"2008-08-23T12:01:19","guid":{"rendered":"http:\/\/www.mrsunstudios.com\/?p=608"},"modified":"2022-05-29T08:23:36","modified_gmt":"2022-05-29T12:23:36","slug":"tutorial-make-a-vertical-shooter-in-as3-part-2","status":"publish","type":"post","link":"http:\/\/www.mrsunstudios.com\/blog\/flash\/tutorial-make-a-vertical-shooter-in-as3-part-2\/","title":{"rendered":"Tutorial: Make a Vertical Shooter in AS3 – Part 2"},"content":{"rendered":"
\n

Table of Contents<\/h3>\n
    \n
  1. Programming the Character<\/a><\/li>\n
  2. Programming the Character – Part 2<\/a><\/li>\n
  3. Creating the Enemies<\/a><\/li>\n
  4. Programming the Enemies<\/a><\/li>\n
  5. Scoring<\/a><\/li>\n
  6. Finishing Touches<\/a><\/li>\n<\/ol>\n<\/div>\n

    Step 2: Programming the Character Pt 2 – Making it Shoot<\/h3>\n

    Well, now that we’ve got the character moving, we have to make him able to shoot. The first step in doing this is to create a MovieClip which will be the bullet. Mine is 5×30 pixels. Give it a name of “Bullet” with the capitals. We also are going to have to export it for actionscript. Hopefully by now, you know how to do this. But, I’ll explain it once again (for the 5th time).<\/p>\n

    Right click the MovieClip and click on “Linkage…”. A window will pop up. In this window, check off “Export for ActionScript” and leave everything just as it is.<\/p>\n

    Now that we’ve got this down, we’re going to make a “Bullet” class. To do this, we have to make an external .as file. Press Command+N if you are on a Mac or Ctrl+N if you are on Windows and under “Type:”, select “ActionScript File”. Then, immediately save this file as “Bullet.as” in the same directory as your main game. Then, within it, type in the following code:<\/p>\n

    \r\n\/\/This is the basic skeleton that all classes must have\r\npackage{\r\n\t\/\/we have to import certain display objects and events\r\n\timport flash.display.MovieClip;\r\n\timport flash.events.*;\r\n\t\/\/this just means that Bullet will act like a MovieClip\r\n\tpublic class Bullet extends MovieClip{\r\n\t\t\/\/VARIABLES\r\n\t\t\/\/this will act as the root of the document\r\n\t\t\/\/so we can easily reference it within the class\r\n\t\tprivate var _root:Object;\r\n\t\t\/\/how quickly the bullet will move\r\n\t\tprivate var speed:int = 10;\r\n\t\t\/\/this function will run every time the Bullet is added\r\n\t\t\/\/to the stage\r\n\t\tpublic function Bullet(){\r\n\t\t\t\/\/adding events to this class\r\n\t\t\t\/\/functions that will run only when the MC is added\r\n\t\t\taddEventListener(Event.ADDED, beginClass);\r\n\t\t\t\/\/functions that will run on enter frame\r\n\t\t\taddEventListener(Event.ENTER_FRAME, eFrame);\r\n\t\t}\r\n\t\tprivate function beginClass(event:Event):void{\r\n\t\t\t_root = MovieClip(root);\r\n\t\t}\r\n\t\tprivate function eFrame(event:Event):void{\r\n\t\t\t\/\/moving the bullet up screen\r\n\t\t\ty -= speed;\r\n\t\t\t\/\/making the bullet be removed if it goes off stage\r\n\t\t\tif(this.y < -1 * this.height){\r\n\t\t\t\tremoveEventListener(Event.ENTER_FRAME, eFrame);\r\n\t\t\t\t_root.removeChild(this);\r\n\t\t\t}\r\n\t\t}\r\n\t}\r\n}\r\n<\/pre>\n
    This code really won't do anything by itself. We have to add it to stage whenever the player presses a button (the Space Bar). We also want to limit how quickly the user can shoot. This will be easy. Just add these variables to the top of the main code:<\/p>\n
    \r\n\/\/how much time before allowed to shoot again\r\nvar cTime:int = 0;\r\n\/\/the time it has to reach in order to be allowed to shoot (in frames)\r\nvar cLimit:int = 12;\r\n\/\/whether or not the user is allowed to shoot\r\nvar shootAllow:Boolean = true;\r\n<\/pre>\n
    Next, we have to add a timer that will increment the cTime<\/tt> variable every frame. We won't use the built in Timer<\/tt> class that ActionScript has (if you even know what that is) because going by frames is much more efficient. Add this code to the moveChar()<\/tt> function:<\/p>\n
    \r\n\/\/Incrementing the cTime\r\n\r\n\/\/checking if cTime has reached the limit yet\r\nif(cTime < cLimit){\r\n\tcTime ++;\r\n} else {\r\n\t\/\/if it has, then allow the user to shoot\r\n\tshootAllow = true;\r\n\t\/\/and reset cTime\r\n\tcTime = 0;\r\n}\r\n<\/pre>\n
    Now we can finally allow the shooting to occur. Add this code to the checkKeysDown()<\/tt> function.<\/p>\n
    \r\n\/\/checking if the space bar is pressed and shooting is allowed\r\nif(event.keyCode == 32 && shootAllow){\r\n\t\/\/making it so the user can't shoot for a bit\r\n\tshootAllow = false;\r\n\t\/\/declaring a variable to be a new Bullet\r\n\tvar newBullet:Bullet = new Bullet();\r\n\t\/\/changing the bullet's coordinates\r\n\tnewBullet.x = mcMain.x + mcMain.width\/2 - newBullet.width\/2;\r\n\tnewBullet.y = mcMain.y;\r\n\t\/\/then we add the bullet to stage\r\n\taddChild(newBullet);\r\n}\r\n<\/pre>\n
    Now if you test your movie, you should be able to shoot! Hurrah!<\/p>\n
    This concludes this part of the tutorial, stay tuned for the next one, creating enemies!<\/p>\n
    The Final Product:<\/h4>\n
    <\/embed><\/object><\/p>\n
    Source Files (zipped)<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
    Table of Contents Programming the Character Programming the Character – Part 2 Creating the Enemies Programming the Enemies Scoring Finishing Touches Step 2: Programming the Character Pt 2 – Making it Shoot Well, now that we’ve got the character moving, we have to make him able to shoot. The first step in doing this is […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[5,8,4,6,68],"tags":[25,8,19,18,68,152,22,150,151,11,149],"_links":{"self":[{"href":"http:\/\/www.mrsunstudios.com\/blog\/wp-json\/wp\/v2\/posts\/608"}],"collection":[{"href":"http:\/\/www.mrsunstudios.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.mrsunstudios.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.mrsunstudios.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.mrsunstudios.com\/blog\/wp-json\/wp\/v2\/comments?post=608"}],"version-history":[{"count":8,"href":"http:\/\/www.mrsunstudios.com\/blog\/wp-json\/wp\/v2\/posts\/608\/revisions"}],"predecessor-version":[{"id":649,"href":"http:\/\/www.mrsunstudios.com\/blog\/wp-json\/wp\/v2\/posts\/608\/revisions\/649"}],"wp:attachment":[{"href":"http:\/\/www.mrsunstudios.com\/blog\/wp-json\/wp\/v2\/media?parent=608"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.mrsunstudios.com\/blog\/wp-json\/wp\/v2\/categories?post=608"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.mrsunstudios.com\/blog\/wp-json\/wp\/v2\/tags?post=608"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}