Steam Blog - Valve
Steam's voice chat system now leverages the SILK audio codec, developed and used by Skype, makers of the world's most popular voice communication service. The SILK codec provides a significant quality improvement over Steam's previous voice technology, at the cost of some increase in bandwidth usage. Steam Voice used to require 15 kbps of bandwidth, whereas SILK is a dynamic bit rate protocol which varies in its use of bandwidth between 8 and 30 kbps, depending on the range of data in the voice signal and current network conditions.

As of today's Steam client update, voice chat using SILK is available to all users of Steam. To start using Steam chat with SILK, simply click the 'Start Voice Chat' button within a friend or group chat on Steam. You can access chat from both the friends list at the desktop, or while in game using Steam’s in-game overlay. You'll find voice chat connectivity and reliability have also been improved with this release.

Steam chat with SILK is now also automatically available for all games that take advantage of the Steamworks Voice API. Valve's own Portal 2, set to release in mid-April, uses this newly updated system to enable voice chat in its cooperative gameplay mode.
Steam Blog - Valve
As a Steam account holder, you can now take advantage of Steam Guard, a new feature of Steam that enables an additional level of account security. Your account may already be protected by Steam Guard, as the new feature automatically begins protecting your account once you've verified your email address with Steam.

With Steam Guard enabled, anyone attempting to login as you from an unrecognized computer or browser must first provide additional, one-time authorization. A special access code will be sent to your contact email address, and this code must be entered into Steam before your first login on an unfamiliar computer is complete. You will also be notified if any login attempts from computers other than those you've authorized occur. Steam Guard essentially acts as a form of "User Rights Management," where you as the user have greater control over access to your stuff.

To read more about Steam Guard and learn how to protect your account, visit our Steam Support knowledge base.
Steam Blog - Valve
Steam Guard, a new Steam account security feature offering two-factor authentication, is now available in beta. As a Steam account holder, you can now take advantage of this additional level of account security, further prohibiting others from gaining access to your account.

As a beta participant, once you've verified your email address with Steam, Steam Guard becomes available for your use and is enabled for your Steam account by default.

With Steam Guard enabled, anyone attempting to login as you from an unrecognized computer must first provide additional, one-time authorization. A special access code will be sent to your contact email address, and this code must be entered into Steam before your first login on an unfamiliar computer is complete. You will also be notified if any login attempts from computers other than those you've authorized occur. Steam Guard essentially acts as a form of "User Rights Management," where you as the user have greater control over access to your stuff.

"Account phishing and hijacking are our top support issues," said Gabe Newell, President of Valve. "With Steam Guard, we've taken a big step towards giving customers the account security they need as they purchase more and more digital goods."

Gabe demonstrated further development of Steam Guard today at the CeBIT computing trade show in Hannover, Germany. In addition to email-based authentication, Steam Guard will soon offer other forms of secondary authentication, such as Intel® Identity Protection Technology, a hardware-based security feature available with the new 2nd Generation Intel® Core™ and Core™ vPro® processors. With IPT, secondary authentication is effortless, as it is provided by the chipset itself.

To opt into the latest Steam client beta and begin protecting your account with Steam Guard, launch the Steam client and visit Steam Settings' Account tab, then changing your beta participation to “Steam Update.”

For more information about Steam Guard and Intel® Identity Protection Technology, visit Steam Support's knowledge base.
Steam Blog - Valve



Steam just made it easier to take and share screenshots of your favorite games.

Press your hotkey (F12 by default) while in any game that runs the Steam Overlay to take screenshots. Then publish them to your Steam Community profile as well as Facebook, Twitter, or Reddit to share them with your friends.

With 1GB of personal Steam Cloud storage, you can upload thousands of screenshots to show off your best moments for all your friends to see. Or you can make them private if you'd rather keep them to yourself.




Use the new screenshot manager to upload your screenshots while still in the game, or at a later time. You can customize your screenshot hotkey by visiting the In-Game section of Steam settings.

To give the new screenshots feature a try, just restart Steam to get the latest client update.

Steam Blog - Valve
Steam screenshots are now available in beta. Now players can use Steam to take and share screenshots from any game that runs the Steam overlay. If you’d like to help test the feature, please opt-in to the latest Steam client beta by going to Steam > Settings > Account then changing your beta participation to “Beta Update”.




Once you’ve signed up for the beta, press F12 in any game to take a screenshot. Screenshots are automatically uploaded to the Steam Cloud after exiting the game, or can be manually uploaded while playing through the in-game overlay. Screenshots can be managed through the Steam Community web site and can be published to your profile to share with your friends. Games that use DirectX 8 and earlier are not yet supported.

You can adjust the screenshot hotkey by visiting the In-Game section of Steam settings. If you prefer to not have your screenshots automatically upload to the Steam Cloud, you can set this in the Downloads + Cloud section of settings. Currently in the works is an interface that will allow you to manage your local collection of screenshots and choose which ones to delete or upload to the cloud manually.

The feature is still a work-in-progress while in beta and we’ll be fine-tuning it over the next couple of weeks. Please visit the Steam Screenshots thread in the Steam Forums to point out bugs, suggest improvements or provide general feedback
Steam Blog - Valve
By now we’re all used to having computers tell us what they think we’ll like. If you’re like us, some internet-retail superbrain has decided that you’re very interested in anything to do with weed killer, because you once accidentally looked at a product page or advertisement for Weed Killer Plus. Well, this week we’ve made the Steam backend brains smarter about how they compute recommendations, by having them factor in things like which games you actually play (as opposed to just what you own, or what you’ve looked at). The results are good, but ultimately we think that any such system can only go so far. Because, really, even if the computer gets it right, it’s still just a computer.

So we’re harnessing a force much more powerful: your friends. THEY are Steam’s new recommendation engine. Oh, and so are you.

Steam now lets you share your opinions directly with each other. Tell all your friends why they should really try Call of Duty: Black Ops. Tell Uncle “Goose” why, for the sake of his mental health, he should probably spend a day in The Undergarden. Or, check out their recommendations for you – they know you better than you think. And if your friends haven’t written any recommendations yet, Steam will still suggest games for you based on what they’ve been playing lately. We built it because... we think it just makes sense. Try it out and let us know what you think.

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Meanwhile, the Steam Publishing Team has been playing BIT.TRIP BEAT, where the team was vying for top spot on the friends leaderboards until William went ahead and set a seemingly unachievable score. The team has agreed that from now on, they'll conveniently 'forget' to include William the next time they challenge the group to a leaderboard competition.
Steam Blog - Valve
Found a game you think your friends should really be playing? Now you can write a recommendation for your friends to share your excitement and start a conversation. Plus, see what games your friends are playing most and what they recommend.

Visit the new 'Recommended For You' page in the Steam Store to find games similar to those you play and love. Steam will suggest games, help you find more content for games you already play, and remind you of items on your wishlist that are on sale.

You can give these improvements a whirl in the latest Beta by visiting Steam client Settings and opting into the Beta Update offered there. And as always, do share your feedback on the Steam Forums.

Note that when recommending a game to your friends, only friends opted in to this beta will be able to see your recommendation.
Steam Blog - Valve
The Steam Wallet has officially been released along with the Team Fortress 2 Mann Co. Store, where players can now purchase items right within TF2.

With Steam Wallet, you can add value to your Steam account using any of the payment methods supported by Steam. Funds in your Steam Wallet may then be used to buy any item available in the Steam store on an in-game store. You can load up your Steam Wallet ahead of time, or wait until checkout. Also, different payment methods can be combined to make a single purchase.

Once you've added funds to your wallet, that money will be used by default for subsequent Steam store purchases. But if you'd prefer to reserve your wallet balance for in-game purchases of Mad Milk, Holy Mackerel and Bushwackas, no problem -- simply select another payment method during checkout. Your wallet funds will be there the next time you're ready to shop at Mann Co., or any other in-game store.

TF2's Mann Co. Store is the first of many upcoming Steamworks in-game stores where Steam Wallet funds can be spent. See the TF2 Mannconomy FAQ for any questions specific to that game. Otherwise, feel free to give the wallet a try for your next Steam purchase, and please let us know what you think.
Aug 20, 2010
Steam Blog - Valve
As usual, the results of this month's Steam Hardware Survey have been collected, processed, and published, creating a useful cross-section of the overall community's installed computer equipment. Thanks to all of you who chose to participate, sharing your system information with us! We mentioned recently that as of July the survey collects a list of participants' installed software as well, and so it is now the Steam Hardware and Software Survey.

Valve has a long history of collecting statistics through our products and then sharing that information with the community (and whoever else will listen.) We use this kind of information to improve our games and services as much as we can, and we've heard from others in the software industry who also consider these reports to be invaluable. So this month, we've posted the software results online alongside the hardware information. There's some pretty interesting information in there, and there's more on the way as we continue to refine our data queries. Have a look and let us know what you think.
Steam Blog - Valve
When we launched Steam on Mac OS X back in May, there was a lot of buzz about performance, particularly relative to Windows running on the same machine. While we met our goal of making sure all of our customers had an acceptable gaming experience at launch, we have spent a large chunk of effort in the intervening months working with Apple and their GPU vendors to close the performance gap with Windows. The combination of changes in our code and the latest graphics update available from Apple today removes a variety of software bottlenecks, resulting in significant graphics performance enhancements for Mac gamers.

Feature Improvements

In addition to low-level implementation changes which have improved performance across the board, Apple has also removed some implementation inefficiencies which allow us to improve visual quality, most notably in the area of GPU occlusion queries.

Occlusion Queries

When we first released our Source engine games on the Mac, we had to turn occlusion queries off but, with the latest update to 10.6.4, we can turn them back on, giving players higher visual quality. If you're not familiar with an occlusion query, it is a mechanism for an application (running on the CPU) to notify the GPU via OpenGL that it would like to know, for some set of draw calls, how many pixels are drawn to the screen, after shading, z-buffering etc. We use GPU occlusion queries for a variety of effects in our game, but one of the easiest to explain is light glows. It's a simple technique that just about every game uses, but it produces a surprisingly convincing effect. What we do is issue queries for light-emitting objects in our scene such as light bulbs or a disc representing the sun. A given light source may be partly or wholly occluded by other geometry in the scene and we use the occlusion query to determine how occluded it is. The percentage of a given light source's screen area which is actually visible is used to scale the intensity of an additive glow sprite which is drawn over the frame without any z-buffering. Because its intensity is attenuated with the occlusion of the light source geometry, the glow sprite fades gently in and out as it becomes more or less occluded by the rest of the scene. It's a simple technique but it appears to be a complex optical effect which helps to convince your brain that you're looking at something truly bright. To illustrate the importance of using light source occlusion to drive glow sprite intensity, we've created a little clip from Half-Life 2: Episode One, which shows the effect with and without the query. Clearly, the left side of the movie shows a convincing glare effect due to the scaling of the glow sprite intensity while the right side of the movie gives a very crude effect, with the glow showing through parts of the scene, breaking the illusion.




From a technical standpoint, the key to the occlusion query feature is that our game can be written in such a way that it can receive the result of a given query asynchronously, at some point later (usually during a subsequent frame). So, while we are using the GPU to perform this computation for us, we aren't stopping CPU execution to wait for the result---we can pick up the result later, since it's OK for this algorithm that the query results are a fraction of a second "stale." So, if implemented properly by the graphics API, occlusion queries cause no synchronization between the GPU and CPU, allowing both processors to stay busy doing work. Unfortunately, prior to the latest software update, occlusion queries caused the CPU-side driver to synchronize with the GPU, perhaps multiple times per frame. This caused large amounts of time during which either the GPU or the CPU was doing no work, significantly reducing system throughput and consequently the game's framerate. This behavior also caused the application's CPU thread to stop processing, as it waited for the driver thread to synchronize with the GPU, resulting in significant loss of CPU throughput as shown in the Shark capture in the image below. In this image, the green horizontal bar is Portal's thread and the pink bar is Apple's OpenGL driver thread. At the point that we've selected on the timeline, you can see from the callstack that we're querying the driver to find out if an earlier GPU occlusion query has been completed. Before the driver can even respond to the game thread, the driver flushes all of its queued work to the GPU in order to synchronize with the GPU, causing the big gap in the timeline on our thread (the big gap in the green bar), during which our game can do no further processing. The way that the occlusion query mechanism is designed, this CPU-GPU synchronization is unnecessary and, with the new software update from Apple, that big gap in the timeline is gone.






Floating Point Validation

Apple has some very nice performance analysis tools that allow us to diagnose performance issues like the occlusion query stall described above. Using these tools, another area that we've seen the driver spending a significant amount of time is in code which validates floating-point parameters that we hand off to OpenGL to drive the logic in our GPU-side shader code. If you're not familiar with the way that processors encode floating point numbers, there are a few special bit patterns that are reserved to handle illegal results that can happen when code inadvertently does something nonsensical like divide by zero. Unfortunately, the way that the OpenGL specification is written, Apple must spend valuable CPU time doing floating point validation to guarantee that their OpenGL implementation behaves correctly in these exceptional cases according to OpenGL conformance tests. Of course, in a high performance application like a game, the CPU time spent in Apple's driver validating floating point data can really add up. We have been able to measure performance improvements in this area with the latest software update, but we are anticipating even more speedups in this area if Apple implements the uniform_buffer_object extension and GLSL 1.3 in a future update. With these additional features, we will be able to sidestep this particular CPU bottleneck, allowing us to win back a bunch of CPU time and, ultimately, performance.

Setting Expectations

We are seeing dramatic performance improvements on iMac (Late 2009 and Mid 2010), Mac mini (Early 2009 and Mid 2010), Mac Pro (Early 2009), MacBook (Early 2009 and Mid 2010) and MacBook Pro (15-inch, Mid 2010) and MacBook Pro (17-inch, Mid 2010) models. Depending on the game, video settings and the hardware, we have measured frame rate improvements from 15% to 120% on these systems. On older systems, we are generally already operating at the limits of the hardware, so it is not obvious that any significant performance improvements can be achieved in the future.

Conclusion

We're very excited about the performance improvements that Apple and the GPU vendors have been able to deliver this summer and we are working with them to further improve performance.
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