TweetFollow Us on Twitter

December 96 - Letters

LETTERS

GAME OUT OF CONTROL
When running the code from Philip McBride's article "Game Controls for QuickDraw 3D" in Issue 27 of develop, I noticed in MySetCameraData that the call to Q3Camera_SetPlacement gets fouled up after a while. The fix shown below was needed.

void MyGetCameraData( 
    DocumentPtr theDocument,
    TQ3CameraObject theCamera)
{
    TQ3CameraPlacement cameraPlacement;
    ...
    Q3Vector3D_Cross(
        &theDocument->zVector,
        &theDocument->yVector,
        &theDocument->zVector);

    // I added this:
    Q3Vector3D_Normalize(
        &theDocument->xVector,
        &theDocument->xVector);
}
-- Flip Phillips

You made the right call. QuickDraw 3D requires all vectors to be of unit length (normalized). So any changes to vectors that could make them not normalized should be followed by a call to normalize those vectors (using Q3Vector3D_Normalize as you've done). If QuickDraw 3D didn' t have this requirement, it would have to normalize vectors itself internally, which would take away from its efficiency.
-- Philip McBride

A SIDE ISSUE
In Steve Falkenburg's article "Planning for Mac OS 8 Compatibility" in develop Issue 26, I read the following:

After some poking around, we figured out that it was assuming that InitWindows called InitMenus as a side effect. The completely new Mac OS 8 implementations of windows and menus no longer have this behavior.

However, Inside Macintosh Volume V states, under the heading "InitWindows" on page 208:

Since the menu bar definition procedure ('MBDF') actually performs these calculations, InitWindows now calls InitMenus directly. InitMenus has been modified so that it can be called twice in a program without ill effect.

I advise the Mac OS 8 engineers to read the "You're never too smart to read the manual" section of the Veteran Neophyte column in the same issue of develop ;-).
-- Reinder Verlinde

Your point is well taken. However, it's worth mentioning that Inside Macintosh: Macintosh Toolbox Essentials (the more current documentation) says no such thing, and in fact says explicitly that InitMenus should always be called after InitWindows. As always, depending on a side effect, even a documented one, is dangerous.
-- Dave Johnson

MORE GOOD STUFF

Look on this issue's CD and develop's Web site for Martin Minow's article, "Timing on the Macintosh," which was recently updated to include a few Java timing techniques. You'll also find some scripting vocabulary advice from Cal Simone.

THINK THESE LETTERS ARE BORING?T hen why not write one of your own? We welcome your letters to the editor, especially regarding articles published in develop. Write to Caroline Rose at crose@apple.com or, if technical develop-related questions, to Dave Johnson at dkj@apple.com. All letters should include your name and company name as well as your address and phone number. Letters may be excerpted or edited for clarity (or to make them say what we wish they did). Address subscription- related queries to order.adc@applelink.apple.com. *

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Latest Forum Discussions

See All

Six fantastic ways to spend National Vid...
As if anyone needed an excuse to play games today, I am about to give you one: it is National Video Games Day. A day for us to play games, like we no doubt do every day. Let’s not look a gift horse in the mouth. Instead, feast your eyes on this... | Read more »
Old School RuneScape players turn out in...
The sheer leap in technological advancements in our lifetime has been mind-blowing. We went from Commodore 64s to VR glasses in what feels like a heartbeat, but more importantly, the internet. It can be a dark mess, but it also brought hundreds of... | Read more »
Today's Best Mobile Game Discounts...
Every day, we pick out a curated list of the best mobile discounts on the App Store and post them here. This list won't be comprehensive, but it every game on it is recommended. Feel free to check out the coverage we did on them in the links below... | Read more »
Nintendo and The Pokémon Company's...
Unless you have been living under a rock, you know that Nintendo has been locked in an epic battle with Pocketpair, creator of the obvious Pokémon rip-off Palworld. Nintendo often resorts to legal retaliation at the drop of a hat, but it seems this... | Read more »
Apple exclusive mobile games don’t make...
If you are a gamer on phones, no doubt you have been as distressed as I am on one huge sticking point: exclusivity. For years, Xbox and PlayStation have done battle, and before this was the Sega Genesis and the Nintendo NES. On console, it makes... | Read more »
Regionally exclusive events make no sens...
Last week, over on our sister site AppSpy, I babbled excitedly about the Pokémon GO Safari Days event. You can get nine Eevees with an explorer hat per day. Or, can you? Specifically, you, reader. Do you have the time or funds to possibly fly for... | Read more »
As Jon Bellamy defends his choice to can...
Back in March, Jagex announced the appointment of a new CEO, Jon Bellamy. Mr Bellamy then decided to almost immediately paint a huge target on his back by cancelling the Runescapes Pride event. This led to widespread condemnation about his perceived... | Read more »
Marvel Contest of Champions adds two mor...
When I saw the latest two Marvel Contest of Champions characters, I scoffed. Mr Knight and Silver Samurai, thought I, they are running out of good choices. Then I realised no, I was being far too cynical. This is one of the things that games do best... | Read more »
Grass is green, and water is wet: Pokémo...
It must be a day that ends in Y, because Pokémon Trading Card Game Pocket has kicked off its Zoroark Drop Event. Here you can get a promo version of another card, and look forward to the next Wonder Pick Event and the next Mass Outbreak that will be... | Read more »
Enter the Gungeon review
It took me a minute to get around to reviewing this game for a couple of very good reasons. The first is that Enter the Gungeon's style of roguelike bullet-hell action is teetering on the edge of being straight-up malicious, which made getting... | Read more »

Price Scanner via MacPrices.net

Take $150 off every Apple 11-inch M3 iPad Air
Amazon is offering a $150 discount on 11-inch M3 WiFi iPad Airs right now. Shipping is free: – 11″ 128GB M3 WiFi iPad Air: $449, $150 off – 11″ 256GB M3 WiFi iPad Air: $549, $150 off – 11″ 512GB M3... Read more
Apple iPad minis back on sale for $100 off MS...
Amazon is offering $100 discounts (up to 20% off) on Apple’s newest 2024 WiFi iPad minis, each with free shipping. These are the lowest prices available for new minis among the Apple retailers we... Read more
Apple’s 16-inch M4 Max MacBook Pros are on sa...
Amazon has 16-inch M4 Max MacBook Pros (Silver and Black colors) on sale for up to $410 off Apple’s MSRP right now. Shipping is free. Be sure to select Amazon as the seller, rather than a third-party... Read more
Red Pocket Mobile is offering a $150 rebate o...
Red Pocket Mobile has new Apple iPhone 17’s on sale for $150 off MSRP when you switch and open up a new line of service. Red Pocket Mobile is a nationwide MVNO using all the major wireless carrier... Read more
Switch to Verizon, and get any iPhone 16 for...
With yesterday’s introduction of the new iPhone 17 models, Verizon responded by running “on us” promos across much of the iPhone 16 lineup: iPhone 16 and 16 Plus show as $0/mo for 36 months with bill... Read more
Here is a summary of the new features in Appl...
Apple’s September 2025 event introduced major updates across its most popular product lines, focusing on health, performance, and design breakthroughs. The AirPods Pro 3 now feature best-in-class... Read more
Apple’s Smartphone Lineup Could Use A Touch o...
COMMENTARY – Whatever happened to the old adage, “less is more”? Apple’s smartphone lineup. — which is due for its annual refresh either this month or next (possibly at an Apple Event on September 9... Read more
Take $50 off every 11th-generation A16 WiFi i...
Amazon has Apple’s 11th-generation A16 WiFi iPads in stock on sale for $50 off MSRP right now. Shipping is free: – 11″ 11th-generation 128GB WiFi iPads: $299 $50 off MSRP – 11″ 11th-generation 256GB... Read more
Sunday Sale: 14-inch M4 MacBook Pros for up t...
Don’t pay full price! Amazon has Apple’s 14-inch M4 MacBook Pros (Silver and Black colors) on sale for up to $220 off MSRP right now. Shipping is free. Be sure to select Amazon as the seller, rather... Read more
Mac mini with M4 Pro CPU back on sale for $12...
B&H Photo has Apple’s Mac mini with the M4 Pro CPU back on sale for $1259, $140 off MSRP. B&H offers free 1-2 day shipping to most US addresses: – Mac mini M4 Pro CPU (24GB/512GB): $1259, $... Read more

Jobs Board

All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.