Sidescrolling Platformer — Part 12 — Basic Enemies

Welcome back to the side scrolling tutorial series. In this session, we will be adding (very) basic enemies to the game, which you can shoot and destroy with the bullets we created previously. This will create a lot of possibilities for what you can do with your game. In later tutorials we will add a scoring system and more advanced A.I. (artificial intelligence) to the enemies, but for now let’s focus on: creating the Enemy class, adding a few enemies to the game map, and destroying them when they are hit by a bullet.

Creating the Enemy Class

Creating the Enemy class is very similar to creating the Bullet class. If you just read Part 10 and Part 11, most of this step will look the same as when we made the Bullet class and symbol.

First, we need art. We need to create a Movie Clip object to represent the enemy on the stage. Feel free to decorate your enemy however you choose — it could be a random, inanimate object, a crazy monster, or anywhere in between.

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Sidescrolling Platformer — Part 11 — Fixing the bullets

Although we did get some functional bullets last time by using the Bullet class, we still need to make some major improvements. First of all, the bullets are added directly to the stage and have no idea about the scrollX and scrollY variables, so they don’t react when the player moves left, right, up, or down. Also, the bullets move at a sluggish pace — if they did react to the player’s movements, you could practically outrun them. Finally, they are never actually removed from the stage, so we waste precious memory that slows down the game. Imagine that we fired 1,000,000 bullets. The game would still be keeping track of all of them, constantly updating their positions, even if they are no longer on the stage. There’s some more code we can add to the bullets to handle all of this, and we are going to implement it in this tutorial.

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Sidescrolling Platformer — Part 10 — Shooting

Welcome back to the flash game tutorial: how to make a side scrolling platformer game in actionscript 3. I can’t believe we’re already up to part ten! As you can probably tell from the title, this tutorial part will exclusively feature shooting. Not all platformer games require this feature, but I’ve had a bunch of requests for this tutorial — probably because side scrolling shooters are an amazing game genre (for example, the classic Metroid games). We don’t have anything yet for our bullets to interact with, but don’t worry — next tutorial we will add the enemies. For now, let’s just focus on getting our hero to shoot.

Here is a preliminary demo of what we’ll be creating. Use the space bar to fire.

An External Actionscript File

…I knew this moment would arrive eventually… the moment when — *gasp* — we finally need to use a custom class and an external actionscript file. If you’ve never programmed anything with Object Oriented Programming before, and you’ve never created an external .as file, this might seem intimidating. Or perhaps you have no idea what I’m talking about. No matter where you stand right now, I hope that by the end of this tutorial you will have a solid idea of what external classes are, why we use them, and how to create a Class for the bullets. In future tutorials we will go into more depth on the topic.

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Sidescrolling Platformer — Part 9 — Animated Player Movements

All great platformers have animated heroes. Even Super Mario, which was released in 1985, used several animations for the player. Why? Because it would look completely unrealistic if Mario just stood frozen in one animation while he runs and jumps around the level. So it makes sense that we should add animations to our player. This will add yet another step of realism to the game.

Try running, jumping, or standing still. See how the player’s animation state reacts:

My art could definitely be improved, but I’ll demonstrate how to create these 3 animations for simplicity’s sake.

The Structure

The most important aspect of giving any game element multiple animation states, is to make sure you structure it correctly. When I first started programming, I tried to put all of the animations on a single timeline, and the resulting structure was too cluttered and complicated that it was difficult to make things work the way I wanted them to. So now I’m sharing with you a simpler method.

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Sidescrolling Platformer — Part 8 — Multiple Levels

Here’s the post you’ve all been waiting for… how to connect multiple levels in your platformer!

Try out this demo. Press the down arrow key upon opening the door to warp to the next level:

After adding the door and key last time, the next step is to make the door lead to the next level. “How?”, you might ask… just read on to see the magic unfold.

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Sidescrolling Platformer ~Part 7~ Keys and Doors

First, I’d like to apologize for my brief hiatus over the past month — I upgraded to a new computer, and Flash was out of commission for a while. But assuming you haven’t abandoned this site yet, here’s the next part of the side scrolling series.

Last tutorial pretty much finished up the bare-bone mechanics and visuals of a basic platformer. So I figured with this tutorial we’d start adding various extra features to spice up the game. This time, we’re adding a collectible key to the level, as well as a locked door which it will open. This door might be the end of one of your levels, which in turn might load a new level afterwards (although we aren’t coding multiple levels in this tutorial — just the door and key which will allow for this in the future).

Make sure you’ve read up through Part 6 of the series.

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Saving and Loading in Actionscript 3 (Mini-Lesson)

One thing you want to do as a game developer is make your players want to come back to your game more than once. And one of the best ways to accomplish this is to enable them to save their data for persistent gameplay. You might expect saving and loading to be tough to implement, but actionscript 3 is helpful enough to include the powerful SharedObject, which makes saving and loading data a piece of cake.

In this tutorial, we will create the following demo. Click the “+1” button a few times to add to your score. If you refresh this webpage without clicking the “save” button, your score will revert to 0 when the page loads. But if you do click the “save” button, your score will load automatically the next time you load the page. Try it out!

Continue reading to learn how to save and load data in actionscript 3

AS3 Health Bar Tutorial (Mini-Lesson)

I’ve received a request to teach how to make a health bar in actionscript 3. Health bars can be found in all sorts of games, so I decided not to confine it to a single tutorial series. Instead, I’ve made this the first of a new section of Mini-Lessons on this site, to cover miscellaneous small game mechanics which can be used in a variety of games.

This tutorial is heavily image-based :-)

Here’s the demo of what we are going to create in this tutorial.

Easy to make. Easy to customize.

Pretty cool, huh?

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Pong ~Part 6~ Scoring Points

Welcome back to the AS3 Game Tuts pong tutorial series. So far in this series we’ve created a working pong game complete with a ball and two paddles. In this tutorial we are going to add a scoring system to the game.

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Pong ~Part 5~ Collisions!

This is it. The tutorial you’ve all been waiting for. The tutorial that will bring everything together. The tutorial which will make you cry out in joy– OK, maybe not, I’m getting a little too excited… but seriously this is a good one.

If you haven’t read the whole series yet, I recommend starting at the beginning.

Part 1: Setting up the Project

Part 2: Programming the Ball

Part 3: The Player’s Paddle

Part 4: The CPU’s Paddle

Let’s get started.

So far, we’ve got the ball to move and bounce off walls. We’ve made the playerPaddle be controllable by the mouse. And we’ve told the cpuPaddle to move up or down depending upon the position of the ball. It’s time to turn this into a “real” game by letting the ball be blocked by the paddles.

Hit Testing

The way Flash handles collisions between two objects on the stage is called hit testing. The way it works is that Flash keeps track of invisible bounding boxes around every object on the screen. These bounding boxes are the smallest possible rectangle that your object can fit inside. So for our paddles, the bounding box is exactly the same shape. But for the ball, instead of using the circular 30px by 30px shape we drew, Flash uses a 30px by 30px square.

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