TweetFollow Us on Twitter

December 95 - Graphical Truffles: Making the Most of QuickDraw 3D

Graphical Truffles: Making the Most of QuickDraw 3D

Nick Thompson and Pablo Fernicola

For those of us on Apple's QuickDraw 3D team, the highlight of SIGGRAPH '95 (the annual conference of the ACM's computer graphics interest group) was having the chance to work with developers who were showing QuickDraw 3D products. Considering that we only started working with developers in December 1994, the number of applications already up and running is inspiring. By the time you read this column, 10 or 15 QuickDraw 3D products will be shipping, including modeling and animation software, 3D hardware accelerators, 3D model clip art, and games. More than 50 developers are actively working on products based on QuickDraw 3D, and those will ship in 1996.

If you're not yet a QuickDraw 3D developer and don't want to be left out, take a look at the develop articles "QuickDraw 3D: A New Dimension for Macintosh Graphics" in Issue 22 and "The Basics of QuickDraw 3D Geometries" in Issue 23. This column gives a hodgepodge of additional information.

IMPROVING ACCELERATOR PERFORMANCE

One of the things that has attracted developers to QuickDraw 3D is seamless access to hardware acceleration. In addition to Apple's PCI accelerator card, hardware acceleration cards have been announced by Matrox, Yarc, Radius, and Newer Technology. If you really want your application to fly, you need to make sure that you're using the fastest renderer possible and that if a hardware acceleration card is installed, you're using the card. If you use the QuickDraw 3D API, QuickDraw 3D will take care of this for you, but there's something else you can do that might improve your application's performance.

Certain cards, including Apple's accelerator card, will yield better frame rates in some situations if you use what we call double buffer bypass, an option enabled by a flag. Double buffering causes all objects to be drawn first into a back buffer; this entire buffer is then copied to the front buffer (the window). If the scene you're rendering is simple and thus takes very little time to redraw -- say, less than 1/10 of a second -- enabling double buffer bypass is faster because it avoids having to copy memory from the back buffer to the front buffer. On the other hand, if you use this option with a complex scene, tearing may occur. Therefore, you may want to time a frame (and take into account the complexity of your models) before using double buffer bypass. To time a frame, call the Toolbox routine Microseconds, draw the frame, call Q3Renderer_Sync to make sure the frame has been fully drawn, and then call Microseconds again and subtract the start time from the end time.

If you're using QuickDraw 3D's interactive software renderer, all the code you need to turn on double buffer bypass is shown in Listing 1.

Listing 1. Turning on double buffer bypass

// Create the renderer.
if ((myRenderer = Q3Renderer_NewFromType(kQ3RendererTypeInteractive))
       != nil) {
   if ((myStatus = Q3View_SetRenderer(myView, myRenderer))
          == kQ3Failure) {  // Handle the error.
      ...
   }   // Set bypass.
   Q3InteractiveRenderer_SetDoubleBufferBypass(myRenderer, kQ3True);
}

The interactive renderer can render using software only or using hardware acceleration. The interactive renderer is set by default to look for the best device possible, so if a hardware accelerator is installed, the accelerator will always be used. On occasion, though, you may want to switch from using hardware to using software (for demos or testing, for example). In this case you must explicitly request the software rasterizer, as follows:
Q3InteractiveRenderer_SetPreferences(myRenderer,
   kQAVendor_Apple, kQAEngine_AppleSW);

INTERACTING WITH INPUT DEVICES

QuickDraw 3D provides an input device abstraction layer that allows you to interact with different input devices without having to write special code for each of them. The sample application NewEra demonstrates interaction with tablets and other input devices; this application is available on the CD that comes with the book 3D Graphics Programming With QuickDraw 3D, and a newer version can be found on this issue's CD.

To take advantage of QuickDraw 3D's input device layer, you need to create a tracker object and associate it with a controller object (created by an input device driver), as Listing 2 does. Once you've set up your tracker, you can poll it to get its new position and orientation, as shown in Listing 3. To reflect the change in your scene, you apply the values returned by the tracker to a transform object, affecting either a particular geometry or group (if an object was selected and being manipulated) or the camera, depending on the interaction model for your application.

Listing 2. Creating a tracker object and attaching it to a controller object

theDocument->fPositionSN = 0;
theDocument->fRotationSN = 0;
theDocument->fTracker = Q3Tracker_New(NULL);
myStatus = Q3Controller_Next(NULL, &controllerRef);
while (controllerRef != NULL && myStatus == kQ3Success) {
   Q3Controller_SetTracker(controllerRef, theDocument->fTracker);
   myStatus = Q3Controller_Next(controllerRef, &controllerRef);
}
Listing 3. Updating position and orientation
// We received a null event; grab a new position and orientation
// for the model.
TQ3Boolean      positionChanged;
TQ3Boolean      rotationChanged;

Q3Tracker_GetPosition(doc.fTracker, &doc.fPosition, NULL,
    &positionChanged, &doc.fPositionSN);
Q3Tracker_GetOrientation(doc.fTracker, &doc.fRotation, NULL,
    &rotationChanged, &doc.fRotationSN);
QuickDraw 3D's input device abstraction layer also makes writing input device drivers easier. For example, it took us about three days to write a driver for the Magellan device from Logitech, Inc., a 3D input device with six degrees of freedom. As illustrated in Figure 1, this device enables movement along the x, y, and z axes, as well as rotation about the three axes.

Figure 1. Magellan: a six-degrees-of-freedom input device (courtesy of Logitech)

SETTING THE CORRECT FILE TYPE

When saving QuickDraw 3D metafiles, you should set the file type as '3DMF', regardless of how the contents of the file are formatted (as plain-text or binary, or any combination of the different types of organization, such as database or stream). This will enable the file to be read or opened by other QuickDraw 3D applications. If you'd like your end users to read a file as text, add an Export As Text option to your application and then set the file type to 'TEXT'. This is helpful for debugging (and for sending questions or bugs to Developer Technical Support).

HAVING FUN WITH CUSTOM ATTRIBUTES

By taking advantage of QuickDraw 3D's custom attributes and extensible metafile format, you can have objects that encapsulate specialized data relevant to your application. For instance, to navigate through the World Wide Web in 3D, you can attach Web data (like URLs) to QuickDraw 3D objects as custom attributes. When those objects or scenes are read into one of the many viewers supporting the URL custom attribute, the viewer can communicate through Apple events with applications like Netscape (or your favorite Web browser) to produce 3D navigation. You'll find a sample application that shows how to do this on this issue's CD.

Custom attributes also enable you to associate sound and other data with objects in your 3D scene.

DEBUGGING

There are two really handy techniques that you can use to diagnose problems you may be having with your QuickDraw 3D application. For both of these approaches to debugging your software, you'll want to make sure that you have MacsBug installed on your machine and that you're using the debugging version of the QuickDraw 3D extension supplied with the QuickDraw 3D development software.

The first technique is to install error and warning handlers, described in our article in develop Issue 22. Error and warning handlers are particularly useful for telling you of potential problems with your use of the QuickDraw 3D library. If you don't install error and warning handlers, you won't know if you're doing something that the library identifies as erroneous. Although we stated this in our original article, many developers missed its significance and thus have experienced longer debugging times than necessary and a great deal of frustration.

The second technique is to use a software tool, the 3D debugger, included on this issue's CD. This application enables you to examine the QuickDraw 3D heap and look at the different objects, their attributes, and their reference count. Please note that you're looking under the hood, so you may encounter untyped blocks, and the reference count for objects may reflect references internal to the QuickDraw 3D system.

LOOKING AHEAD

We'll continue to release great new QuickDraw 3D features, so bring your applications along for the ride. By early 1996 we expect to have all major existing 3D applications on the Macintosh using QuickDraw 3D, along with applications that developers port from other platforms. Many 2D applications will be making use of the 3D Viewer as well.

Watch develop for further articles about other aspects of QuickDraw 3D. Meanwhile, you may want to check out the Addison-Wesley book 3D Graphics Programming With QuickDraw 3D (which includes the QuickDraw 3D development software) and see this issue's CD for the development software and the latest versions of the sample code and utility applications. And for the latest news on QuickDraw 3D, see our Web page at http://www.info.apple.com/qd3d.

NICK THOMPSON (eWorld NICKT), transplanted English soccer fan and member of Apple's Developer Technical Support team, thinks that this could be the year for the Arsenal Football Club. With the acquisition of Dutch star Dennis Bergkamp and England striker David Platt, things are looking up at Highbury. By the time you read this, the Premier League standings will tell if this is the dawning of a new era or more of the same "boring, boring, Arsenal," as those charming Spurs fans like to chant.

PABLO FERNICOLA (eWorld EscherDude), of Apple's Interactive Multimedia Group, is much more relaxed since shipping QuickDraw 3D 1.0. He now has time to eat his dad's great barbecue, dally with his lovely wife, and sleep -- although the latter entails the challenge of trying to get his golden retriever, aptly named Mac, to give up some of the space he takes up in the bed. Pablo's latest research project is to find out exactly what the purpose is for those orange balls that one finds on high power transmission lines.

For more information on making your application work with Magellan, contact Stephan Ilberg at Logitech by sending a message to stephan_ilberg@logitech.com.

Thanks to Robert Dierkes and Fábio Pettinati for reviewing this column, and a special thanks to Dan Venolia and David Vasquez for supplying some of the code and applications discussed.

 
AAPL
$107.18
Apple Inc.
-0.16
MSFT
$46.18
Microsoft Corpora
-0.44
GOOG
$551.43
Google Inc.
+2.10

MacTech Search:
Community Search:

Software Updates via MacUpdate

Cocktail 8.0.1 - General maintenance and...
Cocktail is a general purpose utility for OS X that lets you clean, repair and optimize your Mac. It is a powerful digital toolset that helps hundreds of thousands of Mac users around the world get... Read more
LibreOffice 4.3.3.2 - Free Open Source o...
LibreOffice is an office suite (word processor, spreadsheet, presentations, drawing tool) compatible with other major office suites. The Document Foundation is coordinating development and... Read more
VMware Fusion 7.0.1 - Run Windows apps a...
VMware Fusion allows you to create a Virtual Machine on your Mac and run Windows (including Windows 8.1) and Windows software on your Mac. Run your favorite Windows applications alongside Mac... Read more
OneNote 15.3.2 - Free digital notebook f...
OneNote is your very own digital notebook. With OneNote, you can capture that flash of genius, that moment of inspiration, or that list of errands that's too important to forget. Whether you're at... Read more
Audio Hijack Pro 2.11.4 - Record and enh...
Audio Hijack Pro drastically changes the way you use audio on your computer, giving you the freedom to listen to audio when you want and how you want. Record and enhance any audio with Audio Hijack... Read more
Iridient Developer 3.0.0 beta 3 - Powerf...
Iridient Developer (was RAW Developer) is a powerful image conversion application designed specifically for OS X. Iridient Developer gives advanced photographers total control over every aspect of... Read more
TextWrangler 4.5.11 - Free general purpo...
TextWrangler is the powerful general purpose text editor, and Unix and server administrator's tool. Oh, and also, like the best things in life, it's free. TextWrangler is the "little brother" to... Read more
NeoFinder 6.6 - Catalog your external me...
NeoFinder (formerly CDFinder) rapidly organizes your data, either on external or internal disks, or any other volumes. It catalogs all your data, so you stay in control of your data archive or disk... Read more
Chromium 38.0.2125.111 - Fast and stable...
Chromium is an open-source browser project that aims to build a safer, faster, and more stable way for all Internet users to experience the web. FreeSMUG-Free OpenSource Mac User Group build is... Read more
Default Folder X 4.6.11 - Enhances Open...
Default Folder X attaches a toolbar to the right side of the Open and Save dialogs in any OS X-native application. The toolbar gives you fast access to various folders and commands. You just click... Read more

Latest Forum Discussions

See All

Naailde the Witch Review
Naailde the Witch Review By Amy Solomon on October 30th, 2014 Our Rating: :: PITCH-PERFECT STORYTELLINGUniversal App - Designed for iPhone and iPad Marvelous storytelling, narration, and moving illustrations make this storybook... | Read more »
1st & Goal Review
1st & Goal Review By Andrew Fisher on October 30th, 2014 Our Rating: :: FOR THE D&D LOVING QBUniversal App - Designed for iPhone and iPad 1st & Goal is a board gamer’s football game, a football fan’s board game, and... | Read more »
French Developer Pated Unveils Seashine
French Developer Pated Unveils Seashine Posted by Ellis Spice on October 30th, 2014 [ permalink ] French one-man studio Pated has unveiled Seashine, “a poetic journey into the abyss.” Players take on the role of a jellyfish strugglin | Read more »
Agents of Storm: Tips, Tricks, and Strat...
Calling all agents: Would you like to see what we thought of this rather pretty base builder? Check out our Agents of Storm review! Have you downloaded Agents of Storm, been bowled over by the graphics, and aren’t quite sure what to do next? Never... | Read more »
Any.DO 2.0 Hopes to Help Manage Producti...
Any.DO 2.0 Hopes to Help Manage Productivity Posted by Ellis Spice on October 30th, 2014 [ permalink ] iPhone App - Designed for the iPhone, compatible with the iPad | Read more »
Base Busters Review
Base Busters Review By Jennifer Allen on October 30th, 2014 Our Rating: :: FUN BUT RESTRICTED MIXUniversal App - Designed for iPhone and iPad Mixing up two forms of tower defense gaming and collectible cards, Base Busters is a fun... | Read more »
Sumptus - Personal Expense Tracker in Yo...
Sumptus - Personal Expense Tracker in Your Pocket 1.0 Device: iOS iPhone Category: Finance Price: $3.99, Version: 1.0 (iTunes) Description: Sumptus - a personal finance assistant in your pocket. It’s an ultimate expense tracker... | Read more »
Meat Factory (Games)
Meat Factory 0.1 Device: iOS Universal Category: Games Price: $.99, Version: 0.1 (iTunes) Description: Meat factory harks back to the old days of the game and watch. Easy to pick up and play, but hard to score big. With cute visuals... | Read more »
Medford Asylum: Paranormal Case - Hidden...
Medford Asylum: Paranormal Case - Hidden Object Adventure (Full) 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: Uncover the mystery of Medford City asylum! | Read more »
Secret Files Sam Peters (Games)
Secret Files Sam Peters 1.0.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0.0 (iTunes) Description: [ After the successful iOS release of Secret Files Tunguska, the acclaimed point and click adventure Secret Files... | Read more »

Price Scanner via MacPrices.net

Apple now offering refurbished 2014 15-inch M...
The Apple Store is now offering Apple Certified Refurbished 2014 15″ Retina MacBook Pros for up to $400 off the cost of new models. An Apple one-year warranty is included with each model, and... Read more
Apple drops prices on refurbished 2013 Retina...
The Apple Store has dropped prices on 2013 Apple Certified Refurbished 13″ and 15″ Retina MacBook Pros, with Retina models now available starting at $999. Apple’s one-year warranty is standard, and... Read more
New 2.8GHz Mac mini on sale for $949, save $5...
Abt Electronics has the new 2.8GHz Mac mini in stock and on sale for $949.05 including free shipping. Their price is $50 off MSRP, and it’s the lowest price available for this model from any reseller... Read more
Sale! 3.7GHz Quad Core Mac Pro available for...
 B&H Photo has the 3.7GHz Quad Core Mac Pro on sale for $2649 including free shipping plus NY sales tax only. Their price is $350 off MSRP, and it’s the lowest price for this model from any... Read more
Mujjo Steps Up The Game With Refined Touchscr...
Netherlands based Mujjo have just launched their Refined Touchscreen Gloves, stepping up their game. The gloves feature a updated elegant design that takes these knitted gloves to the next level. A... Read more
Sale! Preorder the new 27-inch 5K iMac for $2...
 Abt Electronics has the new 27″ 3.5GHz 5K iMac on sale and available for preorder for $2374.05 including free shipping. Their price is $125 off MSRP, and it’s the lowest price available for this... Read more
Simplex Solutions Inc. Brings Secure Web Surf...
New York based Simplex Solutions Inc. has announced the release and immediate availability of Private Browser 1.0, its revolutionary new secure web browser developed for iPhone, iPad and iPod touch... Read more
Save up to $180 off MSRP with an Apple refurb...
The Apple Store has Apple Certified Refurbished 2014 MacBook Airs available for up to $180 off the cost of new models. An Apple one-year warranty is included with each MacBook, and shipping is free.... Read more
Apple refurbished 2013 MacBook Pros available...
The Apple Store has Apple Certified Refurbished 13″ and 15″ MacBook Pros available starting at $929. Apple’s one-year warranty is standard, and shipping is free: - 13″ 2.5GHz MacBook Pros (4GB RAM/... Read more
What Post PC Era? – The Mac Bounces Back, Big...
Apple’s fiscal Q4 2014 was an all-time record quarter for Mac sales, with 5.5 million units shipped, representing nearly one million more sales (+21 percent, + 25 percent sequentially) than Apple... Read more

Jobs Board

*Apple* Solutions Consultant (ASC) - Apple I...
…important role that the ASC serves is that of providing an excellent Apple Customer Experience. Responsibilities include: * Promoting Apple products and solutions Read more
*Apple* Solutions Consultant (ASC) - Apple I...
…important role that the ASC serves is that of providing an excellent Apple Customer Experience. Responsibilities include: * Promoting Apple products and solutions Read more
*Apple* Solutions Consultant (ASC) - Apple I...
…important role that the ASC serves is that of providing an excellent Apple Customer Experience. Responsibilities include: * Promoting Apple products and solutions Read more
*Apple* Solutions Consultant - Apple Inc. (U...
…important role that the ASC serves is that of providing an excellent Apple Customer Experience. Responsibilities include: * Promoting Apple products and solutions Read more
*Apple* Solutions Consultant - Apple Inc. (U...
…important role that the ASC serves is that of providing an excellent Apple Customer Experience. Responsibilities include: * Promoting Apple products and solutions Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.