Cocos2d游戏开发5-Text, Fonts, and the Written Word

CCLabelTTF   

CCLabelTTF  *label = [CCLabelTTF labelWithString:@"Hello World"
fontName:@"Marker Felt" fontSize:64];

1. The CCLabelTTF object will use the CCTexture2D class to create an image texture from your text and display that texture onscreen.

2. After the initialization code above, you can use the CCLabelTTF like any other CCNode, add it to your layer, position it, and so forth. 

3. Each time you call the setText method, a new texture is created.

CCLabelTTF *gameBeginLabel =

         [CCLabelTTF labelWithString:@"Game Start" fontName:@"Helvetica" fontSize:64];           
[gameBeginLabel setPosition:ccp(screenSize.width/2,screenSize.height/2)];
[self addChild:gameBeginLabel];
id labelAction = [CCSpawn actions:
                   [CCScaleBy actionWithDuration:2.0f scale:4],
                    [CCFadeOut actionWithDuration:2.0f],
                    nil];
[gameBeginLabel runAction:labelAction];

Anchor Points and Alignment

1. The anchor point is what the texture to use to place it onscreen. Cocos2D defaults to an anchor point in the middle of your texture, so by default your objects are always placed according to their center points. 

2. Default anchor point at the middle of the texture would have a value of (0.5,0.5). Remember, anchor points range between zero and one, with (0,0) on the bottom left and (1,1) on the top right.

[gameBeginLabel setAnchorPoint: ccp(0, 0.5f)];

Listing the Fonts Available in iOS

NSMutableArray *fontNames = [[NSMutableArray alloc] init];
       NSArray *fontFamilyNames = [UIFont familyNames];
       for (NSString *familyName in fontFamilyNames) {
            NSLog(@"Font Family Name = %@", familyName);
            NSArray *names = [UIFont fontNamesForFamilyName:familyName];
            NSLog(@"Font Names = %@", fontNames);
            [fontNames addObjectsFromArray:names];
        }
   [fontNames release];

CCLabelBMFont

1. CCLabelTTFs are great for when you just need the standard iOS fonts and do not have to change the text of the labels very often. 

2. A bitmapped font atlas is an image containing all of the characters you want to dis- play along with coordinates data that allows the characters to be cut out of the master image. 

3. Since the characters are already stored as images, you can- not alter their size without using a different font atlas. 

 CCLabelBMFont *gameBeginLabel =
        [CCLabelBMFont labelWithString:@"Game Start"
         fntFile:@"SpaceVikingFont.fnt"];

Live Debugging

1.