获取随机颜色但避免深色:帮助我的算法

我正试图得到一个随机的颜色。我已经使用蛮力完成了这项工作,但这种方法似乎过于繁琐(尽管分布相当均匀):

- (UIColor *) getRandomColor {
 // GOAL: reject colors that are too dark
 float total = 3;
 float one = arc4random() % 256 / 256.0;
 total -= one;
 float two = arc4random() % 256 / 256.0;
 total -= two;
 float three = total; // UIColor will chop out-of-range nums

 NSMutableArray *threeFloats = [[[NSMutableArray alloc] initWithObjects:[NSNumber numberWithFloat:one], [NSNumber numberWithFloat:two], [NSNumber numberWithFloat:three], nil] autorelease];

 NSNumber *red, *green, *blue;
 red = [threeFloats objectAtIndex:arc4random() % [threeFloats count]];
 [threeFloats removeObject:red];
 green = [threeFloats objectAtIndex:arc4random() % [threeFloats count]];
 [threeFloats removeObject:green];
 blue = [threeFloats lastObject];

 return [UIColor colorWithRed:[red floatValue] green:[green floatValue] blue:[blue floatValue] alpha:1];
}

怎样才能更好呢?我想要红色、绿色和蓝色的均匀分布,不要太暗(否则我会随机抽取三个数字,然后处理掉)。