作者：Frank Cifaldi

二人游戏开发团队——美工TJ Fuller和程序员Nate Murray，为游戏开发商Hiccup开发第一款针对儿童的iPad益智游戏《Jacob’s Shapes》但并未获得成功。也许为儿童设计游戏不是他们的长项。他们得找新用户了。

看到到几段关于猫咪用脚掌玩iPad游戏（给人玩的游戏）YouTube视频，Fuller决定制作一款给猫咪玩的游戏。这款游戏可以很快完成，然后放到苹果App Store上挣点钱，用于“真正的”游戏制作。这款游戏有一个简单的机制：一个物体（一道激光或一只老鼠或最近更新的蝴蝶）在屏幕上像活物一样徘徊，引诱猫咪去抓它。根据猫咪的表现计分，游戏甚至把最高得分放到苹果Game Center上，让所有人都能看到。

仅仅过了三周，再经过当地一家动物收容所的测试，《Game for Cats》隆重登场并吸引了各大媒体的注意，其销售额足以支持他们开发下一款续作，也招来数款山寨之作。

尽管规模不大，但现在已经形成一个针对猫科动物的游戏的正当市场。接下来我们就来分析《Game for Cats》这款游戏的5个设计技巧。

game for cats(from article.wn.com)

1、微妙而自然的移动

猫比人类更擅长发现微妙的移动。如果猫感觉不到它的目标是活物，它就会对之视而不见。《Game for Cats》中的第一个移动完全是用编码制作的，但Fuller认为“太机械了”。

解决方法是抛弃编码，改成记录手指在iPad上的移动轨迹。当激光（或老鼠）在游戏中出现时，它们会缓慢地徘徊一阵子，然后从屏幕上消失。这里采用的是Nate Murray的手指移动模拟方式。

2、高对比度的画面

猫到底能否看到颜色、色相和饱和度，仍然是一个存在争议的话题，但毫无疑问，猫可以分辨明暗。

利用这一点，《Game for Cats》确保目标与背景之间无论在什么模式下都保持高对比度。激光水平仪发射出的激光，被暗色的背景衬托得更加耀眼。而在另一种模式下，深色的老鼠则在极其明亮的奶酪上奔跑。

3、猫咪也爱DLC

就像许多手机游戏，《Game for Cats》在苹果App Store上可免费下载游戏应用，但收关卡下载中收费。如，激光的关卡是免费的，但老鼠的关卡则收费0.99美元。

不幸的是，游戏的初次发行把购买方式弄得太简单了。在发行后不出几天，有不少猫咪在未经主人许可的情况下，意外地购买了关卡。

Fuller笑道：“我们惹上了许多麻烦。人们指责我们引诱猫咪购买关卡。在iTunes页面上，许多人留下评论指责我们是在宰客。”

解决方法是执行一项测试，在收费以前确认购买者是人类，即要求购买者将手停留在屏幕上经应用“扫描”鉴定是否为人类；也就是，购买者的四根手指触点持续数秒后方可移动。这种测试让向来诡计多端的猫咪们也招架不住。

4、游戏暂停方法

Hiccup希望有一种由人类来执行（允许人类切换关卡或发布猫咪所得高分）的游戏暂停方法。但这种方法同时要防止猫咪自己中止游戏，这是一个设计难点。

解决方法就是，人类必须快速连续轻叩屏幕上的特定区域5次，才能暂停游戏。虽然，这个方法基本上是管用的，但Fuller认为猫咪仍然会在偶然的情况下中止游戏，所以“仍然不甚完美”。

cat & ipad game(from gamasutra)

5、以声音作为奖励

只要猫咪在游戏中得分（游戏邦注：也就是，触到移动中的目标），它的得分就会增加，游戏会播放一段声音来奖励猫咪，同时鼓励猫咪继续游戏。比如，激光会发出悦耳的铃声，老鼠会发出惊吓的吱吱声。

Fuller提醒道，虽然将音乐放入游戏的想法很诱人，但他认为这么做可能会破坏效果。

“如果是播放音乐，猫咪不会听到。因为这声音必须是对猫咪有意义的，有目的性的。”（本文为游戏邦/gamerboom.com编译，拒绝任何不保留版权的转载，如需转载请联系：游戏邦）

5 tips for making video games your cat wants to play

by Frank Cifaldi

The two-man team of artist TJ Fuller and programmer Nate Murray at developer Hiccup had something of a flop with their video game debut: Jacob’s Shapes, a simple iPad puzzle game aimed at children. Perhaps children weren’t their forte. Perhaps they needed a new audience.

Noticing several videos on YouTube of cats pawing at iPad games (the human-focused kind), Fuller decided to try and make a game aimed just at them, something that could be done quickly just to get something out on the App Store so they could go back to making “real” games. The game has one simple mechanic: an object on the screen (either a laser light or a mouse or, in the latest update, a butterfly) moves around the screen in lifelike patterns, enticing the cat to touch it. Cats are scored on their performance, and the game even incorporates Game Center, to make sure kitty’s best scores are saved for all to see.

Just three weeks and one playtest at a local animal shelter later (neither Fuller nor Murray are cat owners), Game for Cats debuted, drawing major media attention and enough sales to justify both a sequel and several copycats. Pun intended.

Though it isn’t huge (yet), there is now a legitimate market for video games aimed at felines, and it would be a disservice to Gamasutra’s readership of game developers to not focus on what makes these games work so well. So we sat down for a quick phone chat with Fuller for something of a postmortem of what makes Game for Cats tick.

1. Subtle, natural movements

Cats can detect subtle movements better than we can. If a cat doesn’t sense that its target is “alive,” it’s going to ignore it. The first attempt at movement in Game for Cats was done purely through code, but everything “felt way too mechanical,” Fuller tells us.

The solution was to throw out that code and record finger movements on the iPad. When the laser (or mouse) moves around in the game, creeping around slowly one moment and darting off screen the next, that’s programmer Nate Murray’s finger emulating life.
2. High contrast visuals

There is still some debate as to exactly what cats can and can not see, in terms of color, hue and saturation, but there is no argument against them being able to tell the difference between light and dark.

To take advantage of this, Game for Cats ensures a high level of contrast between the target and the background, no matter which game mode a cat is playing. The laser level offers a bright laser on top of a dark background, for example, while in another mode, a darkly-colored mouse scurries atop an almost offensively bright wedge of cheese.

3. Cats love DLC

Like many mobile games, Game for Cats is a free download that monetizes itself with in-App transactions: specifically, the download includes the laser level for free, and offers the mouse level for an optional $0.99 transaction.

Unfortunately, the initial release of the game made that purchase path a little too easy…in the days immediately following its release, cats everywhere were accidentally purchasing the level without their owners’ permission.

“We got in a lot of trouble,” Fuller laughs. “People were accusing us of tricking cats into making purchases. We got a ton of comments on our iTunes page, people accusing us of trying to rip of them off.”

The solution was to implement a test to make sure the purchaser is human before the charge is allowed to go through: specifically, the purchaser is asked to place their hand the screen and hold it there while the app “scans” to see if you’re human. Or, in reality, it makes sure your four fingertip touch points don’t move for a few seconds, a test even the craftiest of cats would have a hard time circumventing.

4. No pause for paws

Hiccup wanted to implement a way for humans to pause the game (allowing them to switch levels or, perhaps, tweet kitty’s high score), but doing so in a way that prevented cats from pausing the game themselves was a design challenge.

The solution, which “still isn’t perfect,” is that humans have to tap a specific section of the screen five times in rapid succession to pause the game. It works, mostly, but Fuller says that cats still set it off on accident occasionally.
5. Reward with a sound

Whenever a cat successfully scores in the game (in other words, touches the moving target), its score increases and a sound is played, to reward the cat and keep it engaged: the laser chimes, the mouse squeaks in terror.

Fuller warns that while there is temptation to have music in the game, he thinks it would have ruined this effect.

“If there’s music playing, they wouldn’t hear it,” he says. “The sound has to be meaningful, and with purpose.”(source:gamasutra)