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GameFest 2008
I enjoyed GameFest this year, but there seemed to be a lot more excitement last year. It may have just been that there were so many announcements last year and the entire DBP finalist and winners.
The big news announced was the fact that Microsoft is "allowing" game creators to sell their games on Xbox LIVE Marketplace. I used quotes because if you want your game on Marketplace - it has to be sold. You will not be able to give your game away.
So at this point you can sell your game for either 200 points (about $2.50), 400 points (about $5.00) or 800 points (about $10.00). Microsoft takes at least 30% of the sales. Making 70% on a product in this type of distribution model is excellent. Additional fees (yet to be determined) will be deducted for transactions and similar things. If Microsoft puts your game on the "Featured" page in the Marketplace then they will take an additional 10-30%. There is no details at this point regarding how games will be picked for this list. It will be based on some heuristics, but they are still flushing that out.
It is up to the developer as to which tier they want to sell their game in. There is one exception to this. If the game is over 50MB (compressed) then it cannot be sold for the lowest tier (200 points). It must be sold in the middle or high tiers. It is no problem for a game that is under 50MB to sell for more than 200 points. The maximum size a game can be (compressed) is 150MB.
Microsoft announced a new dashboard look and feel a couple of weeks ago during E3. This new look is to try and help with the enormous amount of content in the marketplace. Because of this new dashboard, when a game is created a new requirement is to also create "Box Art", which is basically what it says. If your game was shipping in a box, what would the front cover of the box look like? There may be a requirement (will definitely be an option) to provide more information like "Slideshows" which also fall in line with the dash's new look and feel.
I listened to a talk from Frank Savage, who has a new title of Architect. Frank's talk discussed a few things, but he mentioned "Frank's 3rd Law" which states:
Optimize because you must not because you can!
So this falls right in line with the whole premise of performance that I go by. You have to measure. By measuring you can determine if your game (or application) is performing well enough to meet the goals of the project. So measure, measure, measure. Make notes on some code that may be a problem area if frame rates start to suffer, but don't just dive in and really optimize that code until there is actually a problem. Spend that time writing better game play, or AI or Physics or anything else that is needed for your game.
Shawn Hargreaves had two talks. One was regarding the Content Pipeline (Eli Tayrien also had a talk on the Content Pipeline) and the other was on Networking. As expected, both of Shawn's were very good. In the Content Pipeline talk, I learned about Opaque data which is data you can set in the modeling program that your Content Pipeline can read in and do something with it. For example, let's say you build out an entire 3D level in Maya or 3D Studio Max. You can put place holders in the level for Triggers for example. Those meshes can be assigned Opaque Data that the Content Pipeline can look for. When it finds a mesh that has that Opaque Data custom processing can be done. For the trigger, the code may remove the actual dummy mesh that was used and create a custom trigger that your game can understand. I used this method about 10 years ago when I worked on a train simulator. I didn't have a nice content pipeline to strip it out and had to do it at run time.
His networking talk was phenomenal. Between this talk and a few from the XBOX LIVE track that I attended I learned that the goal for a game is to not send any more than 8kb of data per second. It is extremely bad to send network data at the same rate as your frame rate. Sending 60 packets a second is not a good thing. In another talk they mentioned 15-20 packets per second was good. Something that may not be immediately obvious is the fact that 8kb is not just game data. It also includes the Xbox LIVE header information for the VDP packets (UDP with some encryption specific to Xbox LIVE). It also includes all the voice data. So if you have 16 players in a game and they all talk at the same time the 8kb is used up. While this is acceptable in the Lobby, it isn't during the game play as no game play data will be sent. So it is a good idea to limit who all hears each other. Some ways to limit this is by proximity in the game world. Only the players "physically" close to each other can hear each other chat. For some games, perhaps a way to accomplish this is by only allowing teammates to chat. It was also mentioned that latency (the amount of time it takes for the player to actually receive the packet) is about 500 milliseconds (.5 seconds). This is pretty significant. So network prediction is really required. This involves passing enough information to take an educated guess of where the object will be by the next time the next packet arrives. A good example of this is on the creators club site in the Network Prediction sample.
Mitch Walker had a couple of talks as well. I ended up writing the most with his talks as he had a lot of bullets in his power points. He had a talk discussing what is new in 3.0. The second talk was about creating great community games. Both were very good. I enjoyed going to all of the XNA Game Studio sessions. The sessions were repeated the second day so I was able to hit a couple of other tracks. Well, I went to one other track beside the Xbox LIVE track. I attended two Casual Game sessions. Both discussed Silverlight. I enjoy working with Silverlight and was excited to see it being talked about.
Overall it was a very enjoyable conference. I had a good time and learned some new things. I met a couple of new people as well, so that is always good.
Good things are coming with XNA GS 3.0...
Happy Coding!
-Chad
7/25/2008 11:14:22 AM
Microsoft XNA Unleashed Errata page is now available
There is finally an official Microsoft XNA Unleashed Errata page. It contains fixes to errors found from readers that have posted in the amazon forums.
The errata page can be found here:
http://xnaessentials.com/unleashed/errata.aspx
Hope this helps.
Happy Coding!
-Chad
7/19/2008 4:55:12 PM
Free 1 Year XNA Creators Club Subscription
Well technically it is a Trial subscription, but it allows you to deploy games to your Xbox 360. This is not a premium subscription, so you won't be able to submit games to the current beta site (for XNA Game Studio 3.0 CTP) or review other's games and you won't be able to download premium content like the Ship starter kit. But, being able to deploy a game to your Xbox 360 for free is definitely a good thing!
How do you get this free subscription? Easy - just sign up to be a part of the Dream Build Play competition. The competition is only for Xbox 360 games (this is why Microsoft is giving away the subscription trials). The grand prize winner will get $40,000! That is a nice chunk of change. The winner may also get to sign a deal with Xbox LIVE Arcade much like some winners from last year's competition.
So don't just stand there ... get the free subscription while it is available and start working on your entry!
Happy Coding!
Chad
6/12/2008 11:10:50 PM
New Tutorial: Storing and Retreiving High Scores
A new tutorial was just added to the site. It is a section from Chapter 21 in the book. It shows how to create, load and save a high score list on disk. It works on the Xbox 360 and on Windows. It has also been added to the XNAWiki. Nick Gravelyn started up the site and hopefully it will contain a lot of good content in the coming months.
Happy Coding!
Chad
4/24/2008 7:37:51 PM
Microsoft XNA Game Studio 3.0 Unleashed
I am in talks with the publisher about the upcoming book Microsoft XNA Game Studio 3.0 Unleashed. The original Microsoft XNA Unleashed book which covered XNA Game Studio Express has been successful and has received many good reviews and has been recommended on the XNA forums many times. Of course, with a technical editor like Shawn Hargreaves, it is to be expected.
Since there is only a year between XNA Game Studio 2.0 and XNA Game Studio 3.0 we decided to not create a 2.0 specific book. I was going to create 4 new chapters for networking, but those will just be added to the 3.0 book. Since the decision was made to not update the book to 2.0, I upgraded the code included in the book to 2.0 and released it yesterday.
Besides networking chapters, the new 3.0 book will also include information on creating 2D games for the Zune. It will include features that are specific to that hardware device as well. The book will also include information on distributing games on the Xbox 360 through the Xbox LIVE Community Games service.
All of the items that made the first book a success will be included: Performance Considerations, Physics, AI, Game State Management, Particle Systems, 2D Demos, 2D Parallax Side Scroller Game, 3D Demos, Extending the Content Pipeline (including the new parameters introduced in 2.0), and a complete 3D game.
There is a lot of information coming, so if you have bought the original book and are looking to learn some of the topics mentioned above it may be worth getting it now. Otherwise, just sit tight and the 3.0 book should be released shortly after Microsoft releases the product (around Holiday 2008). So it could be as early as a couple weeks after the launch, but could be a long as two months after the launch. We can all hope for the former.
As always, if there are any questions with the current Microsoft XNA Unleashed book, please ask a question in the book's forum on amazon.com.
Happy Coding!
-Chad
3/29/2008 3:48:44 PM
Updated 2.0 code for XNA Unleashed is now available for download!
I am pleased to announce that the code for the book has been updated and is now available for download. The files can be located at http://xnaessentials.com/downloads.aspx
As always, questions about the book, or the updated code can be directed to this book's forum located at amazon.com.
Happy Coding!
-Chad
3/28/2008 1:34:12 PM
XNA Game Studio 3.0 is coming
Spring 2008 is when the beta is supposed to be out ... Holiday 2008 is when it should be released.
I can't wait!
Some very exciting things are coming including:
Develop 2D games for the Zune
FAQ:
http://forums.xna.com/thread/46553.aspx
Discussion Thread:
http://forums.xna.com/thread/46557.aspx
Deploy your Xbox 360 game to anyone on Xbox LIVE!
FAQ:
http://forums.xna.com/thread/46554.aspx
Discussion Thread:
http://forums.xna.com/thread/46558.aspx
General info on Game Studio 3.0
http://forums.xna.com/thread/48067.aspx
Things to note is that VS2008 will be used. I love VS2008, so this is great news. I would love to be able to use some of the C# 3.5 language features, but it is unknown if any of that will be available yet. Using LINQ to query a scene graph would be excellent fun!
Lots of information and as much as possible will be in my new book - Microsoft XNA Game Studio 3.0 Unleashed. More details on that to follow ...
Happy Coding!
-Chad
3/2/2008 7:30:00 AM
Academic Trial Memberships
There was a press release on December 12th that discussed three main topics:
1. XNA Game Studio 2.0 Supports Xbox LIVE.
2. Microsoft will provide a free trial membership in the XNA Creators Club beginning in January, allowing faculty members and students to use XNA Game Studio 2.0 and Xbox 360 for instructional purposes.
3. Another Dream-Build-Play Warm-Up challenge is underway.
The piece that is new is number 2 above. Here is the excerpt from the press release:
Academic Trial Memberships
Since its release last December, XNA Game Studio has been an incredible success, with 750,000 downloads, adoption by more than 300 universities worldwide and at least nine textbooks on the tools in development. In subjects from computer science to fine arts, introductory courses to graduate and research projects—XNA Game Studio is helping faculty members and students explore the boundaries of applied gaming technology in education.
Along with XNA Game Studio 2.0, Microsoft will also provide a free academic trial membership in the XNA Creators Club beginning in January, allowing faculty members and students to use XNA Game Studio 2.0 and Xbox 360 for instructional purposes.
---
There are a couple of universities and community colleges that either have picked up my XNA Unleashed book or are going to this coming semester. There has been some discussion about providing some extra material to help instructors. If you are thinking of adopting my book and are interested in any supplemental material, leave a message on the Amazon forum for the book.
Happy Learning!
-Chad
12/14/2007 9:16:27 PM
XNA Game Studio 2.0 Released Today
The XNA Team made the announcement that XNA Game Studio 2.0 has been released. The Net Rumble starter kit is a good place to see the most anticipated added feature of networking in place.
Some tips if you try to upgrade any of your 1.0 code to 2.0:
1. Make sure you have the Project Upgrade Wizard installed.
2. If you have sound in your project, you will want to open the project with the new XACT tool and then save it under the newer version.
3. If you use Render Targets you should read this local help page.
4. This doesn't require immediate change, but the LoadGraphicsContent and UnloadGraphicsContent methods are now obsolete. LoadContent and UnloadContent should be used instead. Shawn has an excellent post about this.
In general, read this local help page (available after installing XNA Game Studio 2.0).
Happy Coding!
-Chad
12/13/2007 8:46:51 PM
Dream Build Play 2008 Warm-Up Challenge Announced
Dream Build Play 2008 Warm-Up Challenge has just been announced.
http://www.dreambuildplay.com/main/Default.aspx
Make sure you visit the page for all official rules. They are looking for a game with excellent AI. In fact, the winner could possibly get an internship with the Microsoft Research guys. I met a couple of these guys at Gamefest 2007 -- they are some very smart guys!
Here is a small blurb about the judging criteria ... while the chapter in my book on Artificial Intellegence will not be enough to make your game win - it will definitely help get you there.
Judging criteria
Contest entries will be evaluated by 3 standards:
- Game A.I. (60%) – Game A.I. will be evaluated based on how it serves the game design, and how it contributes to the game experience. Novelty and originality of the AI is appreciated but not required: a novel use of an existing state-of-the AI method is in itself considered to be innovative. General applicability of the AI concepts/techniques is also valued
- Fun Factor (20%) - The fun factor will be evaluated based on how the game design creates a positive user experience. This may include how intellectually challenging, relaxing, stimulating or satisfying the game is. A key indicator for the fun factor will be the desire to keep playing.
- Production Quality (20%) – Make your game world as polished as possible and hook your judges with exciting, entertaining action. Production quality will be evaluated based on how seamless the overall game play is, the quality of the assets used, and the structure, readability and level of documentation of the code.
Entry requirements
To take part in the Silicon Minds Warm-Up Challenge, you must:
- Be 16 years or older.
- Live in an eligible country/region. (For full eligibility requirements, see the Official Rules.)
- Create and submit your game in English.
- Game size limit: Single uploaded .zip file should not be more than 200MB
Happy Coding!
-Chad
12/7/2007 10:31:05 PM
Forums "Added"
I wanted to announce that I look at Amazon's forums for this book. So if there are any questions or comments, etc they can be directed there.
Amazon Forum for Microsoft XNA Unleashed
While I'm here, I should mention that I have been patiently waiting for another good review to come my way. I have read good reviews on the web of the book, but none of those have made their way to Amazon. A sampling of what I found ...
http://p2p.wrox.com/topic.asp?whichpage=1&TOPIC_ID=63544𡋗
http://www.albertrosa.com/index.php/2007/08/14/xna-splat-game-goals/
http://www.kinlan.co.uk/2007/08/review-microsoft-xna-unleashed-by-chad.html
http://blog.radioact1ve.com/2007/08/reading-part-15.html
http://forums.xna.com/thread/19922.aspx
I am contemplating writing another book on a different subject as well as adding more content (tutorials) to this site and making a second edition of this book when the XNA Framework 2.0 comes out. However, the last thing I want to do is provide a book that isn't valuable for the majority of people buying it. If you enjoyed the book, would you consider writing a review on Amazon? For that matter, if you didn't enjoy the book could you also write a review? It would really help me determine if I should continue in the book authoring business or gracefully fade away ... Of course it would help others to know if they should separate with their hard earned money or not.
Happy Coding (and Reviewing)!
--Chad
9/25/2007 9:20:16 PM
Gamefest 2007 - Day 2
Gamefest 2007 - Day 2 was good. All of the big announcements happened on day 1, but it was very exciting to see the animation possibilities with the SOFTIMAGE|XSI Mod Tool. The advanced debugging session was great! I will probably create a tutorial on some of the advanced techniques discussed including one I didn't know about -- very cool.
Happy Coding!
--Chad
8/15/2007 9:39:56 PM
Gamefest 2007 - Day 1
Gamefest 2007 - Day 1 was great! Highlights of some of the things announced today are as follows:
- XNA Game Studio 2.0 is the only sku (no longer Express and never will be a Pro).
- XNA Game Studio 2.0 sits on top of all Visual Studio skus (Visual C# Express, VS 2005, etc)
- XNA Game Studio 2.0 will support networking via Xbox Live. Certain things will not be available like Acheivements, Leaderboards and Matchmaking. However, being able to netword the Xbox 360 and Windows together in the same game is amazing. Also, being able to easily setup code to either run a system link network game or over Xbox Live (and of course local multiplayer) is excellent.
- XNA Game Studio 2.0 includes Gamer Services (Gamer tags, gamer card, game defaults, privledges, etc)
Day 1 was great. The top 20 of the Dream Build Play entries were absolutely awesome! The XNA Framework simply rocks. Go write great games!
8/14/2007 2:49:38 AM
XNA Unleashed Shipping to Warehouses
This past Friday, the books were being completed at the printers and shipping out to the warehouses. There were "normal production delays" at the printers. I later found out that the book was being printed at the same printer that printed the Harry Potter book. What? My XNA Unleashed title is held up due to a book with only 10 million back orders being printed? What's up with that?! :)
The publisher got a small shipment in yesterday and overnighted me a copy. So I am looking at the book now. Hopefully Amazon will receive their copy soon and for the 10 million that have back ordered the book -- oh wait, wrong book -- well for the people who have pre-ordered this book, they should get their copy soon.
Shawn Hargreaves of the XNA Development team has posted a nice blurb about the book on his blog. Thanks Shawn!
Shawn did a fantastic job in being the technical editor of this book. Basically, if it is good - then it is because of Shawn. If it is bad, then it is because I ignored his advice! :)
If you haven't subscribed to this feed, well ... you should because it will have updates to the books as we find errors (what errors!?). Also, when any new demos or tutorials are added, this blog will have an update so you can be notified.
Happy Coding!
-Chad
7/25/2007 5:45:37 PM
XNA Essentials Site Launched
Welcome to XNA Essentials! This blog will be updated whenever the site is updated. When new tutorials, updates to the book, downloads and other site information is updated, the blog will get an entry. If you subscribe to the RSS feed then you can be notified when new content is available on this site. I hope this site proves to be beneficial to the XNA Community!
Happy Coding!
-Chad
7/21/2007 2:59:04 PM