问iOS中的3d文本效果

EN

- (UIImage *)imageWith3dString:(NSString *)text
{
    CGFloat fontSize = 150.0;
    CGFloat fontSizeDelta = 3.0;
    CGFloat fontOffset = 5.0;

    NSString *fontName = @"Bebas";
    UIFont *font = [UIFont fontWithName:fontName size:fontSize];
    CGSize textSize = [text sizeWithFont:font
                       constrainedToSize:CGSizeMake(CGFLOAT_MAX, CGFLOAT_MAX)];

    CGSize size = CGSizeMake(textSize.width, fontSize);

    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef ctx = CGBitmapContextCreate(NULL,
                                             (int)size.width,
                                             (int)size.height,
                                             8,
                                             (int)(4 * size.width),
                                             colorSpace,
                                             kCGImageAlphaPremultipliedLast);

    // Draw with shadow
    CGContextSetShadowWithColor(ctx, CGSizeMake(0, 0), 10.0, [UIColor colorWithWhite:0.0 alpha:0.6].CGColor);

    CGContextSetRGBStrokeColor(ctx, 1.0, 1.0, 1.0, 0.6);
    CGContextSetAllowsAntialiasing(ctx, YES);  
    CGContextSetLineWidth(ctx, 2.0);
    CGContextSetTextDrawingMode(ctx, kCGTextFillStroke);

    CGContextSetRGBFillColor(ctx, 222 / 255.0, 222 / 255.0, 222 / 255.0, 1.0);
    CGContextSetCharacterSpacing(ctx, 2.6);
    CGContextSelectFont(ctx, [fontName UTF8String], fontSize - fontSizeDelta, kCGEncodingMacRoman);
    CGContextShowTextAtPoint(ctx, 0.0, 3.0 + fontOffset, [text UTF8String], text.length);

    CGContextSetShadowWithColor(ctx, CGSizeZero, 0.0, NULL); // disable shadow
    CGContextSetCharacterSpacing(ctx, 1.0);
    CGContextSelectFont(ctx, [fontName UTF8String], fontSize, kCGEncodingMacRoman);
    CGContextShowTextAtPoint(ctx, 0.0, 3.0, [text UTF8String], text.length);


    CGImageRef imageRef = CGBitmapContextCreateImage(ctx);
    UIImage *image = [UIImage imageWithCGImage:imageRef];

    CGColorSpaceRelease(colorSpace);
    CGImageRelease(imageRef);
    CGContextRelease(ctx);

    return image;
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    UIImageView *imageView = [[UIImageView alloc] initWithImage:[self imageWith3dString:@"3"]];

    [self.view addSubview:imageView];
}