TweetFollow Us on Twitter

Game Sprocket Intro

Volume Number: 13 (1997)
Issue Number: 2
Column Tag: Game Development

Sprockets are Forever

By Jeremy Vineyard, Viperware

Macs Were Made to Play Games

The Beginning...

When I was a child, I used to beg my parents for quarters to play in the local arcade. Wasting thousands of hours with this activity, I developed a passion for creating games. The desire to create my own games magnified with every quarter I spent.

Reality is often harsh, especially for the would-be game developer. I discovered that games can be very difficult to write. A good game developer must have extensive knowledge of animation techniques, music composition, sound recording, graphics synchronization, algorithm design, data structures, and more. Game developers lose sleep over the slowdown caused by CD-quality sound and full-screen scrolling graphics, and the complexities of an arcade game type environment. Until fairly recently, there wasn't much documentation explaining how to write games, if you wanted to learn, you did so by trial and error.

Not long ago, Apple officially announced something that Mac lovers have known for years: the Mac is a game machine. In fact, the Mac is a great game machine, featuring built-in support for high-resolution graphics and CD-quality sound. Along with this announcement, Apple resolved to help Mac game developers write even cooler games for the Mac. The result - Apple's Game Sprockets.

What is a Sprocket?

A sprocket is a component of Apple's new game development architecture. Each sprocket adds extra features to the MacOS that specifically benefit those who are writing games. There are six sprockets currently under development by Apple: DrawSprocket, SoundSprocket, InputSprocket, NetSprocket, SpeechSprocket, and QuickDraw 3D Rave. SpeechSprocket is just a repackaged version of Apple's Speech Recognition Manager. Game Sprockets will run only on PowerMacs, but certain sprockets may be ported to 68k in the future. Game Sprockets require the newest system software including OpenTransport 1.1, Display Manager 2.0, and Sound Manager 3.2.1.

DrawSprocket

Prepare for battle! Flames rupture your view; sirens wail. You have the enemy in your sights. Fire! The screen jerks and the action grinds to a halt. Unexpectedly, you find yourself waiting for the screen to refresh. As the computer calculates the next frame of animation, your senses are brought to terms with reality. You lose interest, quit, and go to your living room to read a book. Full-screen, high-resolution graphics are quite possibly the bane of all computer games.

The Macs make great game machines, but they lack certain characteristics that make the primeval PCs more suitable for playing games. One noticeable shortcoming is that unlike PC's, most Macs don't have page-flipping. Page-flipping is the ability to almost instantly switch frames of animation by simply telling the display device (the monitor) to look somewhere else in memory for the display data (the graphics). DrawSprocket provides transparent support for page-flipping on the Macs that support it, and falls back on more compatible methods for those that don't. When page-flipping is not available, DrawSprocket reverts to using CopyBits, which is much slower than page-flipping because QuickDraw must copy the entire contents of each frame of animation onto the screen.

DrawSprocket also supports multi-buffering, with which the next frame of animation can be drawn even while the current frame is being copied to the screen. Multi-buffering can decrease the animation bottleneck that occurs when the processor overtakes the speed of the display device.

Figure 1. Select a Display with DrawSprocket.

DrawSprocket offers common game-related tasks such as a user interface for selecting monitors and providing an easy way for games to take control of the entire screen, which includes hiding the menu bar and blanking all unused monitors. DrawSprocket takes care of fading the screen to any color by altering a monitor's gamma tables. This is good for making a cool fade, setting up the screen for the next scene, and fading back into the game.

DrawSprocket makes it easy for you to include an underlay in your game. An underlay is an image that is always behind all other graphical elements. For example, you might have a scrolling picture of a mountain that is always in the background. In the future, DrawSprocket will support overlays allowing game developers to easily implement foreground images.

DrawSprocket's routines can provide your game with a consistent frame rate so that the animations don't change speed when they are becoming more or less processor-intensive. For the animated elements, Apple provides a sprite manager within QuickTime.

InputSprocket

Have you been frustrated while trying to use a Mac joystick? Until the introduction of InputSprocket, the Mac had no built-in support for game input devices, resulting in emulated performance by the Mac joysticks, flight sticks, and game pads.

InputSprocket is an API for the Mac joystick developers that provides a consistent user experience when using joysticks and other game-related input devices on the Mac. Joystick manufacturers write drivers for their devices that communicate with games about the elements of the joystick. Some examples of elements are buttons, controllers, directional pads, and others that are common to game-related input devices. Games that use InputSprocket can interact directly with these elements, eliminating the need for the elements to be emulated through the mouse or keyboard.

You can create your own interface for choosing the active game device and assigning functions to game controls, but InputSprocket provides a standard user interface for you.

Figure 2. InputSprocket Interface.

For a game input device to work with InputSprocket, a driver must be written for that device. As of the writing of this article, no joystick manufacturers shipped InputSprocket drivers for their products, but companies such as Gravis and Thrustmaster have demonstrated prototype InputSprocket drivers. InputSprocket has problems working with some third-party input devices such as Kensington mice, but Apple developers are working to fix this problem.

QuickDraw 3D RAVE

QuickDraw 3D RAVE (Rendering Acceleration Virtual Engine) is a Hardware Abstraction Layer (HAL) that allows game developers who write their own 3D rendering engines (as does Bungie for Marathon) to take advantage of the features offered by 3D accelerator cards when they are present. QuickDraw 3D Rave is a stripped-down version of QuickDraw 3D, and it is highly optimized, making it ideal for game developers who need every amount of speed they can get.

Games communicate with QuickDraw 3D RAVE by converting their rendered images into triangles, which RAVE then sends to the accelerator card if present, or otherwise emulates in software. In addition to supporting 3D accelerator cards, RAVE will soon be cross-platform, allowing game developers to easily port their low-level 3D rendering code.

SoundSprocket

3D games are the rage nowadays. This is evident by the huge sales of games like Doom and Marathon. Along with freedom of movement comes the responsibility to make the user experience as realistic as possible. Players are expecting to be drawn into their games more and more as computer processing power increases. 3D sound adds an extra dimension of reality and helps the game developer write really cool games.

Figure 3. Configuring a Sound Device for 3D Sound.

SoundSprocket adds the capability of making sounds appear to come from positions relative to the game player. This allows realistic feedback such as: "The aliens are to my left!" and can make game play much more enjoyable. Like all the other sprockets, SoundSprocket provides a standard user interface for configuring sound output devices to take maximum advantage of their 3D sound capabilities.

Future versions of SoundSprocket promise to add effects such as altering sound as it travels through the environment. Sound will be heard differently based on the humidity of the environment, and will even be able to travel through dense fog or water. Sound will also reverberate by bouncing off walls.

You don't have to have a 3D game to benefit from 3D sound. Most games that use sound effects can benefit from more realistic sound and a more in-depth user experience.

NetSprocket

As adrenaline pulses through your veins, your finger slips from sweat as you pull at the trigger. The force from the rocket blast kicks you back. Splat! A direct hit. You drool in ecstasy as your opponent's corpse splatters to the ground. Are you competing in Bloodsport? No- you have just finished off the last of your assailants in a networked game of Marathon. Unlike competing against a personality-less computer, going head-to-head with your best friends (or even your enemies) can be a heck of a good time.

Macs have been one of the easiest platforms to network together since their introduction. Setting up a local area network is as simple as connecting a cable between two Macs. This ease of use takes most of the pain out of adding networking to Mac games. However, because there are many different protocols that a network might support (IP, IPX, AppleTalk, Serial, etc.), a game developer probably won't have time to implement all of these protocols in addition to testing the reliability of their network code.

NetSprocket provides a set of high-level routines designed specifically to help developers add networking code to their games. NetSprocket hides the low-level details of the network from the programmer and takes care of many tasks that the developer would otherwise be forced to implement.

Figure 4. Hosting a Network Game.

Figure 5. Joining a Network Game.

NetSprocket is based on a client/server architecture in that one player acting as a server hosts a game session, and other players join as clients to the network game. In the future, NetSprocket will provide more models other than the client/server model for interacting between networked players. NetSprocket hides the implementation details of supporting various protocols, saving the developer time needed to re-write the networking code for each protocol. NetSprocket is fast and fault tolerant - when one computer in the networked game crashes, it doesn't bring down everyone else. Since the low-level network code is already written, NetSprocket can save a game developer hundreds of hours of work.

NetSprocket assigns each player a player ID and a player type. Player types might include referees, observers, and participants. Players can belong to groups (red team, black team, etc.).

A networked game works like a conversation - players pass messages back and forth. This communication activity is known as a protocol. A network protocol is very much like a conversation - players ask questions and wait for responses. Although NetSprocket makes it very easy to pass messages between networked players, knowledge of designing protocols is important. Fortunately, designing protocols is not a difficult topic to learn, and can end up being somewhat addicting. (Or maybe it's just me?)

To Infinity and Beyond

Apple is not supporting 68k machines with its Game Sprockets architecture. Until Apple develops 68k versions of Game Sprockets, Game Sprocket developers must limit their audience to PowerMac users.

Apple has a tarnished reputation for settling for complacency when it releases new technologies to developers (see QuickDraw GX, AOCE). In order for Game Sprockets to thrive, Apple must provide game developers with an abundance of tools, source code, and updates to the existing API. Thankfully, Apple has been doing a good job with Game Sprockets, keeping updates coming steadily and keeping in touch with the developers who use the technologies.

Apple's Game Sprockets are definitely a step in the right direction if they want to remain a competitive OS solution into the future. I look forward to seeing games released that take advantage of the features that are offered. Thank you to those people within Apple who are working hard to bring more cool games to the Mac!

Footnote

The Internet is a great place to find information on Apple's Game Sprocket architecture. Here are some URL's that can help you get started.

Apple's Game Sprocket Page

http://dev.info.apple.com/evangelism/games/games.html

Developer University Course- Game Development with Sprockets

http://devworld.apple.com/dev/du/Using_Game_Sprockets/Using_Sprockets.html

Licorice Web Page for Game Sprocket Developers

http://www.viperware.com/licorice

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Apple iBooks Author 2.5 - Create and pub...
Apple iBooks Author helps you create and publish amazing Multi-Touch books for iPad. Now anyone can create stunning iBooks textbooks, cookbooks, history books, picture books, and more for iPad. All... Read more
TunnelBear 3.0.1 - Subscription-based pr...
TunnelBear is a subscription-based virtual private network (VPN) service and companion app, enabling you to browse the internet privately and securely. Features Browse privately - Secure your data... Read more
ExpanDrive 5.4.0 - Access cloud storage...
ExpanDrive builds cloud storage in every application, acts just like a USB drive plugged into your Mac. With ExpanDrive, you can securely access any remote file server directly from the Finder or... Read more
Opera 40.0.2308.62 - High-performance We...
Opera is a fast and secure browser trusted by millions of users. With the intuitive interface, Speed Dial and visual bookmarks for organizing favorite sites, news feature with fresh, relevant content... Read more
Apple iOS 10.0.2 - The latest version of...
iOS 10 is the biggest release of iOS ever. A massive update to Messages brings the power of the App Store to your conversations and makes messaging more personal than ever. Find your route with... Read more
Herald 7.0 - Notification plugin for Mai...
Note: Versions 2.1.3 (for OS X 10.7), 3.0.6 (for OS X 10.8), 4.0.8 (for OS X 10.9), 5.0.2 (for OS X 10.10), and 6.0.3 (for OS X 10.11) are no longer supported by the developer. Herald is a... Read more
Postbox 5.0.2 - Powerful and flexible em...
Postbox is a new email application that helps you organize your work life and get stuff done. It has all the elegance and simplicity of Apple Mail, but with more power and flexibility to manage even... Read more
Yummy FTP Pro 1.11.10 - $29.99
Yummy FTP Pro is an advanced Mac file transfer app which provides a full-featured professional toolkit combined with blazing speeds and impeccable reliability, so whether you want to transfer a few... Read more
Tidy Up 4.1.17 - $29.99
Tidy Up is a full-featured duplicate finder and disk-tidiness utility. Features With Tidy Up you can search for duplicate files and packages by the owner application, content, type, creator,... Read more
Logitech Control Center 3.9.5 - Keyboard...
Logitech Control Center (LCC) is designed to support OS X and allows you to take full advantage of your Logitech keyboard, mouse, or trackball. With the LCC you can: Browse the Internet using... Read more

How to build and care for your team in D...
Before you hit the trail and become a dog sledding legend, there’s actually a fair bit of prep work to be done. In Dog Sled Saga, you’re not only racing, you’re also building and caring for a team of furry friends. There’s a lot to consider—... | Read more »
How to win every race in Dog Sled Saga
If I had to guess, I’d say Dog Sled Saga is the most adorable racing game on the App Store right now. It’s a dog sled racing sim full of adorable, loyal puppies. Just look at those fluffy little tails wagging. Behind that cute, pixelated facade is... | Read more »
Let the war games commence in Gunship Ba...
Buzz Lightyear famously said, “This isn’t flying, this is falling – with style!” In the case of Gunship Battle: Second War, though, this really is flying - with style! The flight simulator app from Joycity puts you in control of 20 faithfully... | Read more »
How to get a high score in Fired Up
Fired Up is Noodlecake Games’ high score chasing, firefighting adventure. You take control of a wayward firefighter who propels himself up the side of a highrise with blasts of water. Sound silly? It is. It’s also pretty difficult. You can’t... | Read more »
NBA 2K17 (Games)
NBA 2K17 1.0 Device: iOS iPhone Category: Games Price: $7.99, Version: 1.0 (iTunes) Description: Following the record-breaking launch of NBA 2K16, the NBA 2K franchise continues to stake its claim as the most authentic sports video... | Read more »
Dog Sled Saga (Games)
Dog Sled Saga 1.0.1 Device: iOS Universal Category: Games Price: $3.99, Version: 1.0.1 (iTunes) Description: A game by Dan + Lisa As a rookie musher, foster a dogsledding team whose skills will grow if they're treated right. Week by... | Read more »
60 Seconds! Atomic Adventure (Games)
60 Seconds! Atomic Adventure 1.2 Device: iOS Universal Category: Games Price: $2.99, Version: 1.2 (iTunes) Description: 60 Seconds! is a dark comedy atomic adventure of scavenge and survival. Collect supplies and rescue your family... | Read more »
Tons of Bullets! (Games)
Tons of Bullets! 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Tons of BulletsA retro 2D pixel platformer infused with tons of bullets and tons of features!Fight as Kenji the Ninja and... | Read more »
Sorcery! 4 (Games)
Sorcery! 4 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: *** PLEASE NOTE: Sorcery! 4 requires a minimum of iPad 3 or iPhone 4 *** An epic adventure through a cursed citadel of monsters,... | Read more »
Building the perfect Animation Throwdown...
Animation Throwdown is a casual card game full of plenty of inside jokes from some of your favorite cartoons. It’s accessible as far as card games go, but that’s not to say that it hands your victories to you easily. There’s quite a bit that goes... | Read more »

Price Scanner via MacPrices.net

Duplicate Sweeper Free On Mac App Store For O...
To celebrate the launch of Apple’s latest macOS Sierra, Stafford, United Kingdom based Wide Angle Software has announced that its duplicate file finder software, Duplicate Sweeper, is now available... Read more
13-inch Retina MacBook Pros on sale for up to...
B&H Photo has 13″ Retina Apple MacBook Pros on sale for up to $150 off MSRP. Shipping is free, and B&H charges NY tax only: - 13″ 2.7GHz/128GB Retina MacBook Pro: $1174.99 $125 off MSRP - 13... Read more
Evidence Surfaces Pointing To New A10X Chip F...
Citing a job description for a Project Lead position at Apple’s Austin, Texas engineering labs, Motley Fool’s Ashraf Eassa deduces that development is progressing well on Apple’s next-generation in-... Read more
Check Print’R for macOS Allows Anyone to Easi...
Delaware-based Match Software has announced the release and immediate availability of Check Print’R 3.21, an important update to their easy-to-use check printing application for macOS. Check Print’R... Read more
Apple refurbished 11-inch MacBook Airs availa...
Apple has Certified Refurbished 11″ MacBook Airs (the latest models), available for up to $170 off the cost of new models. An Apple one-year warranty is included with each MacBook, and shipping is... Read more
Apple refurbished 15-inch Retina MacBook Pros...
Apple has Certified Refurbished 2015 15″ Retina MacBook Pros available for up to $380 off the cost of new models. An Apple one-year warranty is included with each model, and shipping is free: - 15″ 2... Read more
Major Version 5 Release Of Free myTuner Radio...
AppGeneration Software has announced the release of myTuner Radio 5.0.1, an important update to their live radio app for iOS and Android platforms. With myTuner Radio, you can listen to more than 30,... Read more
TheAppStore Searches And Filters iOS And macO...
Boston based InchWest has announced the official launch of TheAppStore, a free web based service that lets users search iOS and Mac apps on the web without iTunes or the App store. TheAppStore... Read more
2TB Time Capsule on sale for $199, save $100
Amazon has 2TB Apple Time Capsules on sale for $199 including free shipping. Their price is $100 off MSRP. Choose Amazon as the seller when making your purchase, rather than a third party seller. Read more
12-inch 1.2GHz Rose Gold Retina MacBook on sa...
Amazon.com has the 2016 12″ 1.2GHz Rose Gold Retina MacBook on sale for $1254.02 including free shipping. Their price is $345 off MSRP, and it’s the lowest price available for this model from any... Read more

Jobs Board

Senior *Apple* Administrator - Pratt Instit...
POSITION SUMMARY: Directs the coordination and standardization of campus-wide Apple systems, including planning, analysis and implementation of Apple -related Read more
Restaurant Manager (Neighborhood Captain) - A...
…in every aspect of daily operation. WHY YOU'LL LIKE IT: You'll be the Big Apple . You'll solve problems. You'll get to show your ability to handle the stress and Read more
*Apple* Retail - Multiple Positions- Napervi...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
US- *Apple* Store Leader Program - Apple (Un...
…Summary Learn and grow as you explore the art of leadership at the Apple Store. You'll master our retail business inside and out through training, hands-on Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.