Rapid XNA Game Development

Day 17: Wow, How Easily One Forgets

2009-01-13T21:29:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 93 Spent
Media Budget: 200 Hours, 50 Spent
Other Time: 13 Hours Spent
Day Breakdown: 24 Hours Media (Over 2 Days)

Well, it seems I had to go back and relearn how to model and skin a bit. It's been about six months since I've done any heavy model production, skinning, and painting textures. It is amazing the pace at which skills are lost when you do not use them, but it's also equally amazing how quickly they come back once you dive back in.

This delay has put me slightly behind. I'm still one or two small ships short, the first two bosses, and all three player ships. I am making about 2 models per day now so models should be finished Saturday or Monday for the first 5 levels. At that point it should only take me a day or two to finalize the first playable demo!

Day 15: The Stage is Set!

2009-01-07T15:44:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 93 Spent
Media Budget: 200 Hours, 26 Spent
Other Time: 13 Hours Spent
Day Breakdown: 3 Hours of Code, 3 Hours Media

Well, just about everything that needs to be in place for the game is now in place. I still need to code in the actual splash screen and main menu, but with the framework in place that is trivial to do. The problem I'm facing now is that I have all the coding parts in for a working game, but there is only test media. I actually started drawing the story board for the game today and will finish that up tomorrow and start work on production level media and levels.

It will likely take me until Friday to have the first official level to show off, and Saturday before the first two levels are produced. My main goal right now is to have the first 5 levels of the game done a week from Friday (1/16/09), at which point I'll release a playable demo. In order to do that I'll need to design the 3 primary player ships (there are 5 in total, but you have to unlock 2 of them), at least 10 small enemy ships along with the first two bosses, and a bit of coding for background object type effects, fog, and some other small bits of code. That's a lot to get done in a week, and we'll see if I'm up to the task!

Goals For Tomorrow: Finish up Story Board, Mesh for "The Eagle" Ship

Day 14: Another Day with Nothing to Show

2009-01-06T20:17:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 90 Spent
Media Budget: 200 Hours, 23 Spent
Other Time: 13 Hours Spent
Day Breakdown: 10 Hours of Code

My code time budget is quickly running dry and I'm starting to think I would have just been better of hand coding the forms vs. trying to make a system, but it's too late now. All the basic text elements are working fine and the function calls are hooked into the game. I just need to add in images and models into the system and I'll be able to create as many menus and interface gadgets as I want with little extra coding effort.

I should have something to show off tomorrow! Funny how I can do a whole particle system in a single day, but it is going to take me three day to build the menu/state system. However, the menu is one of those fit and finish thing that many independent game developers over look and a frustrating menu system can put a player off from a game right away.

Goals for Tomorrow: Finish the Menu/Forms

Day 13: Long Day and Nothing to Show

2009-01-05T21:45:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 80 Spent
Media Budget: 200 Hours, 23 Spent
Other Time: 13 Hours Spent
Day Breakdown: 11 Hours of Code

Well it was a long day and I have nothing in the way of screen shots or movies to show off what I did, mainly because it really isn't all that exciting. I laid a very nice groundwork for my menu system, but it still has a ways to go and I'll need to figure out some of the sticker aspects of things still. However, on the whole I'm happy with the framework and it should work out nicely.

I'm doing my best to hard code as little form/menu interaction into the game as possible, instead I'm using a framework that reads form files and allows the user to interact with the forms while providing function based hocks for the required action in the game itself. Basically I'm creating a form system that is more in line with how you would build a form inside an IDE. From a coding perspective it is turning out to be a beautiful piece of work, but it takes time. In the end I do think that the extra work will be worth it.

Goals For Tomorrow: More Forms and Menus

Day 12: Today Had to be Done

2009-01-03T20:51:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 69 Spent
Media Budget: 200 Hours, 23 Spent
Other Time: 13 Hours Spent
Day Breakdown: 3 Hours of Code, 1 Media, 6

Well, days like today aren't exactly the most enjoyable to spend in the programming world, but they have to be done. I spent much of today looking through the code that has been so quickly brought together and made sure everything was well commented and easy to understand. I added those hours spent into the new label of other time as the time spent wasn't directly designed to push the game forward as my code budget time is. Most everything was commented well to begin with, only a few section needed clarification and I actually found a couple of bugs at the code level without ever noticing them in game (and they could have gone unnoticed for quite some time and been real head scratches when they did pop up).

On the actual coding side I managed to tie up a number of lose ends that have been on my TODO list. This includes things like getting weapons to fire from points on the, adding ship level effect emitters and a number of smaller changes to ensure game play remains unchanged at any resolution, aspect ratio, and tile safe percentage. You can see some of the changes in the screen shot for the day.

Goals For Tomorrow: None, I'm taking Sunday off. Monday will bring the menu system.

Day 11: Wow that's a Big Ship!

2009-01-02T20:33:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 66 Spent
Media Budget: 200 Hours, 22 Spent
Day Breakdown: 7 Hours of Code, 3 Media

And the bigger they are the harder they fall! I really didn't feel very good today and I spent most of the morning doing thing other than programming. I really didn't think I would manage to get the game logic for boss fights coded in, but I plugged away at it and got everything working. There is still a lot of AI based programming to do, but the logic for the boss fights is all present.

The boss fight that I created to test the coding was a simple play on damage types. The missile turrets don't hit shields very hard, but they will tear through armor. The giant thrusters will tear through your shields, but mostly leave your armor untouched. Trying to take out the thrusters while the turrets are still up results in a quick death, but do things the other way (as the video shows) and the fight is simple.

Goals for Tomorrow: Menu System/Logic (feeling well) or Lose Ends (not feeling well)

Direct YouTube Link (Higher Quality)

Day 10: How Far Things Have Come!

2009-01-01T20:24:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 59 Spent
Media Budget: 200 Hours, 19 Spent
Day Breakdown: 3 Hours of Code, 11 Media

Today is much less about words, as much more about the video. Sounds are now in the game and playing on various events. I didn't have time to normalize all the sound files and tune them to their importance, but I did do a few tweaks so more important sounds are easier to hear. The hardest part of the day was the music system, I create a system that dynamically puts various pieces of the music together as the level is being played so it can dynamically adapt to the intensity of the level. You can't really hear it in the movie and I really didn't have time to make a top quality audio tract, but that's what the huge media time budget is for. Without any further ado, here is the video!

Goals for Tomorrow: Boss Fights!

Direct YouTube Link (Higher Quality)

Day 9: Where is my Easy Button?

2008-12-31T17:41:00.000-08:00

Happy New Year!

Project: Space Game (Untitled)
Code Budget: 120 Hours, 56 Spent
Media Budget: 200 Hours, 8 Spent
Day Breakdown: 9 Hours of Code, 1 Media

I honestly figured that developing a particle system was going to be more difficult that it actually was. I used the Authoring Particle Systems Using XML and the Content Pipeline tutorial as my baseline, but I changed up how things worked in order for it to adapt to the flexibility of a game's needs. I added in an option to change the fx script factor, and more importantly I wrapped the entire system inside a manger that handles the individual particle systems. Now when the game goes to add a new particle the manager checks to make sure it is already managing that specific particle system, if it's not that system is created at run time and added to the manager. The advantages of this is the game ends up with a single particle system manager and not a new object that has to be managed in a seperate thread for every effect that will be used on the game (even when not being used).

I went through and added effect data to the following events, which effect to display is loaded by the XML Level file where applicable:

Enemy Ship Explosion
Bullet Travel Emitters
Bullet Collission Explosions
Player Explosion
Shield Collission
TODO: Model Tag Emitters

Going into today I thought that I was only going to be able to get the system in place and that pretty new screen screen shots of the effects actually playing themselves out in the game was going to have to wait...boy was I wrong! I thought about making a movie, as screen shots are no longer really doing the game justice, but a game really just doesn't feel right without sounds and music. That will be coming tomorrow, and hopefully I'll be able to put together a movie!

Goals for Tomorrow: Sound and Music System!

Shield Being Hit, Notice the Missile's Smoke Trails

General Action With Energy Weapons and Ship Explosions!

More General Action, Looks Like I'm going DOWN!

Day 8: Let There Be HUD

2008-12-30T18:32:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 47 Spent
Media Budget: 200 Hours, 7 Spent
Day Breakdown: 7 Hours of Code, 2 Media

Well, working with the 2D Side of XNA isn't so bad and the HUD went together as it should have. Most of the time today was spent coding in the power mechanics of the game and tying up some lose ends. (Keeping Track of Score, Deaths, Invulnerability, and the Like) The HUD now provides a look into the players state and gives feedback via the score. As you'll see from the screen shots there is a lot going on.

The main portion of the HUD is the power and armor/shield displays. The power display in the low level depletes as you fire your weapon or use your speed boost to better maneuver and it replenishes quickly over time. The faint blue bar under the power indicator shows how much power is currently being sent to regenerate the ships shields, this can be anywhere from 10% to 50%, however the more power being diverted to the shields the slower the power bar will replenish itself. The second bar shows the status of your shields and armor, shields are always damaged first and will restrengthen slowly over time, faster if you divert more power to your shields, however your armor can only be repaired via special power ups.

Most of the rest of the HUD is self explanatory, you have the name of the current level, number of lives, number of currency collected (you'll spend currency to upgrade your weapons, engines, shields), and your current score. The format of these is a throwback to old arcade games that always used to display zeros for the entire length of the field. The green targeting cross hairs helps will aiming your weapons down range, though additional steps may be needed once game play testing begins.

Goals for Tomorrow: Particle System Foundation

Note that the Power Going to the Shields is Low

Note that the Power Going to the shields is High

Day 7: It's a GAME!!!

2008-12-29T18:29:00.001-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 40 Spent
Media Budget: 200 Hours, 5 Spent
Day Breakdown: 8 Hours of Code

Well, the most difficult part of the game is now behind me. Collision detection is now in the game and working wonderfully. The player can fire their weapons and even fly into the enemy ships in an effort to destroy them, and the enemy ships can fire back in an attempt to destroy the player. I've created a virtual world that the user can interact with complete with goals and challenges: in other words, it is now officially a game!

As you'll probably be able to tell from the screen shots I used Oriented Bounding Boxes for my collision detection. I thought about using sub spheres, but decided against it because most of the ships will be a single model mesh making using sub spheres more difficult. The computational cost of the Bounding Boxes is actually quite low when I realized that 95% of all checks are going to fail on the basic Z component check, which can programmed in to be the first check. I've shown the Debug level code in the screen shots here which allows for the drawing of the bounding boxes.

Goals For Tomorrow: HUD, Player Shield/Power Regen

Eep, I need to dodge all those bullets now!

Looks like I need to get better, Red Box indicates I'm dead! QQ

Day 6: Emitters are a Go!

2008-12-28T11:48:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 32 Spent
Media Budget: 200 Hours, 5 Spent
Day Breakdown: 2 Hours of Code

The Ship Emitters are a Go! The XML Level Data is getting rather complex (see level file, the C# Reader and Writer), but the emitters will assist in level creation, intensity, and replayability as they can generate random streams of ships. I added a couple of emitters that spawn left and right moving ships right at the start of the level and it really kicked up the intensity of playing the level, Screen Shot Below.

Goals For Tomorrow: Collision Detection, Bullet and Ship Collision Damage

Day 5: Fire Away!

2008-12-27T16:17:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 30 Spent
Media Budget: 200 Hours, 5 Spent
Day Breakdown: 5 Hours of Code

Well, Bullets are now flying. The bullet manager handles incoming and outgoing, straight and homing, and the ship AI was adjusted to handle 3 different firing mechanics. Bullets can be fired by the enemy ship based upon step intervals, fixed duration, or randomly: best part is that all of the information to control these aspects are already present in the XML Level Data I've been working so hard on.

I wasn't able to get into the collision detection portion of things as of yet as I just ran out of time tonight and it looks like it's going to have to wait until Monday. I'll only have about 5 hours to code on Sunday and I'd rather give myself more time to code in the collision detection.

While playing with the game today and looking at the Level Data I did notice something that I want to add in tomorrow: Ship Emitters! Right now individual ships have to be placed in the level, but adding in emitters would let me create an emitter that will spawn X number of ships at set intervals. The current level is described as 15 individual ships, but it could be described as 3 emitters. Also the Emitters could randomly pick from a list of provided ships and AIs helping to make levels a bit more random and unpredictable.

Goal For Tomorrow: Ship Emitters

Outgoing and Incoming Bullets, Some Player's are Homing

Incoming Homing Bullets, boy are they tough to dodge!

Day 4: The Stage is Set!

2008-12-26T19:01:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 25 Spent
Media Budget: 200 Hours, 5 Spent
Day Breakdown: 8 Hours of Code, 1 Media

I'm now about a quarter of the way through my coding budgeting and the game is already starting to take shape. The Level loader is working beautifully and I'm glad that I took the time to learn about the Content Pipeline and how to use it to load data into the game. After three short days of working with the Content Pipeline I now have the background, enemy ships, and some basic scripted AI all loading from an XML File (See the Level XML File).

I only coded in three basic types of "AI" currently in the game and none of them have them firing their weapon yet. I'm reluctant to call this AI as there is no real Intelligence behind the movements yet; it is just playing a movement and rotation script. Still more advanced scripting will be coded in once the core of the game is finished and I start working on boss fights.

I'm very happy with how far the game has progressed in just four short days. The Stage is set for the player to interact with the enemy ships and for them to fight back, at which point the core of the game is finished.

Goals for Tomorrow: Bullet System, maybe even Collision Detection

Basic Up and Down Linear (Ships in the Foreground)

Accelerated Side to Side Movement (Ships in the Foreground)

Random Movement that has the Ships Moving Randomly to the Corners

Day 3: More Fun With XLM Levels

2008-12-25T14:47:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 16 Spent
Media Budget: 200 Hours, 4 Spent
Day Breakdown: 4 Hours of Code

Wow, the Content Pipeline is Anal. I spent most of the day working on getting the large background objects to load up from my XML Level File (See XML Level File). The Content Pipeline does a fantastic job of checking your classes and making sure that everything you declare as a public variable is included in the XML data, it even has to be in the same order as it is declared in your code. I spent the better part of the day figuring out why it was throwing an error saying that XML Element "Model" not defined. Turns out it was part of the parent class, so I ended up trimming out a lot of unneeded public information from my basic game object class.

All told I'm happy with how things turned out today. I have a sky box in place and a very extensible background object system that will let me add planets, space stations, even a tunneling or ground level. Here are a couple of screen shots and you can see the game is starting to look like a game! The object field that was present in the screen shots from Day 2 gets lost in the still images with the sky box, however when the game is running they still do a fantastic job of giving the player the feeling of flying through space. In the screen shots you'll note that the planet is rotating and moving slowly towards the player.

Calling things a bit early today with it being Christmas Day and all.

Goals for Tomorrow: Load ship and AI data, hopefully getting some enemy ships to show up!

Day 2: XLM Content Loading

2008-12-25T14:16:00.000-08:00

Project: Space Game (Untitled)
Code Budget: 120 Hours, 12 Spent
Media Budget: 200 Hours, 4 Spent
Day Breakdown: 8 Hours of Code, 1 of Media

After spending most of my first day on a basic player model and setting the foundation for the game code, my second day proved to be a bit more of an uphill struggle as I learned the ins and outs of extending the XNA content pipeline to read a custom XML file. My goal for the day was to lay the foundation for a XML based level loading system, create an objectfield to help simulate motion along with a sky box.

Setting the Foundation of the level loading system proved to be a bit more work than I was hoping for, probably because I've never worked with XNA or C# before. However, in the end I found this fantastic tutorial that helped me out greatly. In the end I was able to get the Content Pipeline Loading the Level Data and the Objectfield that the player flys through working. Below are some screen shots of the game in the current state. Not to much to see here of yet, and you can't even get the feel for the random objects flying at you and spinning at random rates.

Goals For Tomorrow: Level Loading of a Skybox, Larger Background Models, Set the Foundation For the Loading of Ships/AI