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Posts Tagged ‘Games’

Build Your Own Game (BYOG) – Using CreateJS and Box2dWeb

I am excited to be presenting tonight at the Charlotte Game Dev group.

Here is a summary of what we will be presenting:

In this session, we will take a look at what it takes to build your own game using CreateJS and Box2DWeb.

We will look at the code necessary to create a simple game as well as talk about how all the moving parts fit together.

Bring your laptop and come prepared to build an application. We will also showcase how you can take your game and launch it as a native Windows 8 application. This is a great feature of Windows 8 since it natively speaks HTML and JavaScript.

Hope to see all of you there!

Introducing Tank Commander!

February 26, 2013 1 comment

In this post, I wanted to describe Tank Commander and talk about some of the logic that went into building it.

Here is the description of the game:

Tank Commander is a game that teaches you programming logic. You get one chance to write your program and destroy the base. You can play any level but your real skill comes when you can write all the programs without a single error!

The following are some of the screens in the game:

Tank Commander - Splash

Main Screen

screenshot_02252013_234142

screenshot_02252013_235058

screenshot_02252013_234251

screenshot_02252013_234354

screenshot_02252013_234438

The main premise behind the game was to use it as a tool for teaching my boys how to think logically and perform some simple programming. My oldest can win each level with a couple of tries. My youngest is still working but he has the first couple levels down perfect!

I have really enjoyed building games using HTML5 and the Canvas. It is so easy with CreateJS and the suite of tools it provides. I have looked at other libraries but it keeps pulling me back to use it for my games so far. I decided to build on the simple level editor that I built for my first game, Milo the Mosquito as it was a very straight forward approach. I did, however, make it a little more complicated as I wanted to have a little more metadata about the levels.

Probably, one of the most challenging parts about creating the game, was trying to make sure that I had a good collision detection.  I didn’t really need to worry about this in my other game but now with moving objects, I needed to be a little more careful.  Thankfully, due to the grid that I was using, I simply rolled out a poor man’s collision detection system using the X and Y coordinates.  That is one of the reasons why you see them in the game. There were originally meant for debugging purposes only but I liked them so much that I decided to keep them.

I also had to create a simple parser for the input the user typed into the programming console. I know that this experience can be improved upon by providing some compiler errors or hints to help the user play the game.

In my first release I provided a toggle for all sounds in the game but I changed that a little in the next release to have a toggle for both sounds and music in the game. I also decided to save the settings of what the user chose automatically so that when they came back to the game it would be ready.

Another area that I found was not the most intuitive was the original main menu. When a user went to the selected a level from the dropdown, the level automatically started. This was very irritating if you clicked on the home button in a level and then wanted to go back.

I now have a “Go” button that takes the user to the selected level.

In my original design of Milo the Mosquito, I had a separate level text file. I changed this up a little and now use JSON for Tank Commander. This provided me with the ability to define more complex levels and behaviors.

The following is the first level for Tank Commander as JSON:

[{
	"id": 1,
	"name": "Fire!",
	"level": "intro",
	"background": [
		"1NNNNNN2",
		"W......E",
		"W......E",
		"W......E",
		"W......E",
		"W......E",
		"W......E",
		"3SSSSSS4"
	],
	"game": [
		"......P.",
		"P...T...",
		"........",
		".....P..",
		"..P.....",
		".P.....P",
		"....X...",
		"......P."
	],
	"tankDirection": "north"
},
]

I left out the rest of the levels for brevity. I have two layers to my game so that I could create a background and then position the other assets on the screen. I finally have a direction so that I can tween the tank into the correct orientation. This is also beneficial as it allow me to have a single sprite sheet with animation going in a single direction and be able to tween all the other direction by just rotating the items.

Here is a quick legend of what I am doing with the “background” and “game” arrays.  I wanted to have a background where I could define a nice border instead of the same tile.  This is the reason for the following values: 1, N, 2, W, E, 3, S, 4.  It doesn’t take a lot of imagination to see what I am representing here.  I also used the “.” character to represent the tiles within the border.

The “game” array is basically the same, I am representing different tiles by using different characters: P, T, X.

Here is a screen shot of the layer rendered:

screenshot_02252013_234108

This is a simple approach and can be used for a lot of time layouts.  It is used in a lot of 2D platform games.

Although, I have ran into some challenges while developing this game, I really enjoyed building it using HTML5 Canvas and JavaScript.  The other thing that I absolutely love is the ability now to natively target Windows 8.

Hope this helps and inspires you to write one as well…

Introducing Milo the Mosquito

November 22, 2012 3 comments

In this post, I am going to describe the game Milo the Mosquito that I created and show some of the screens.

Here is the description of the game:

Milo is an annoying mosquito that just needs to be caught.
Play through the levels and try to catch Milo as fast as you can.
Once you have Milo trapped, tap on him to squish him for good.

The Home screen is as follows:

If you click on the help button, you are presented the Help screen:

When you click play from the Home screen you are presented with the Levels screen:

Next you can click on each level and play the game:

As you can see it is a fairly simple game in that you are trying to catch Milo and squish him before he escapes.  I will now just go over at a high level the architecture and structure I used to create the game.

If you have noticed already, I have been spending a lot of time building applications for Windows 8 in HTML, CSS, and JavaScript.  I have consciously made this decision because I want to be able to author applications that give me the ability to reach across to other platforms without needing to learn a new language or API.  I have held the MVP status in Client Application Development and I have extensive experience in WPF and Silverlight but I wanted to be sure that I could get a good feel for the development experience in building Windows 8 applications in HTML.

The first conscious decision I made with building this game was to use the new HTML 5 feature of the Canvas.  I also decided to use the JavaScript library, CreateJS.  There is a lot of tremendous documentation on this library.  The creators of  Pirates Love Daisies are behind this awesome library.

Within CreateJS, I used the following:

  • EaselJS – to help with managing the canvas
  • PreloadJS – to help manage my assets in the game
  • SoundJS – to help manage my audio in the game
  • TweenJS – to help with creating animations in the game
  • Zoë – to help create spritesheets from Flash

I also used the EasyStar library as a pathfinding engine for Milo to use for determine his escape route.

When working with the canvas, you are left to managing what you are to the canvas and also removing items.  I tried to be as modular as possible by creating top level managers for each screen and implementation.

Finally also created a level editor so that I could use a simple text file represent a level.  The following is the text representation for the level screen you see above:


..............
.XXXXXXXXXXXX.
.XXXXXXXXXXXX.
.XXXXXXXXXXXX.
.XXXXXXXXXXXX.
.XXXXXXXXXXXX.
.XXXXXXMXXXXX.
.XXXXXXXXXXXX.
.XXXXXXXXXXXX.
.XXXXXXXXXXXX.
.XXXXXXXXXXXX.
.XXXXXXXXXXXX.
.XXXXXXXXXXXX.
..............

As you can see, I used “.” as an exit point for Milo.  I represented the playing board by using “X” and finally I represented Milo as an “M”.

I hope this gives you a simple idea into what it takes to build a simple game.  The great thing about using HTML 5 is that you can develop it and test it with you favorite browser and have almost no changes to get it to work in a native Windows 8 application.

Hope this helps…

7 tips to Make building Win 8 apps in HTML/Javascript a Breeze

November 10, 2012 Leave a comment

Looking forward to speaking today at the RDU CodeCamp!

Here are the slides for my presentation.

See you there…