关于CATransform3D矩阵变换的简单解析

关于CATransform3D矩阵变换的简单解析

效果图:

我能能够用上的CATransform3D其实很简单,并不复杂.

CATransform3D有着4种东西我们可以设置.

1. 透视效果(由m34的值决定)

2. 位移变换(主要是x,y方向)

3. 缩放变换

4. 空间旋转

源码:

//
//  RootViewController.m
//
//  Copyright (c) 2014年 Y.X. All rights reserved.
//

#import "RootViewController.h"
#import "CATransform3DOperation.h"
#import "YXGCD.h"

@interface RootViewController ()

@property (nonatomic, strong) GCDTimer *timer;

@end

// 将角度转换为弧度
#define DEGREES_TO_RADIANS(d)  ((d) * M_PI / 180.f)

@implementation RootViewController


- (void)viewDidLoad
{
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor blackColor];
    
    // 给Layer一个图片内容
    UIImage *image = [UIImage imageNamed:@"4"];
    CALayer *layer = [CALayer layer];
    layer.frame = CGRectMake(0, 0, image.size.width, image.size.height);
    layer.position = self.view.center;
    layer.borderWidth = 4.f;
    layer.borderColor = [UIColor redColor].CGColor;
    layer.contents = (__bridge id)image.CGImage;
    [self.view.layer addSublayer:layer];
    
    // 6s后执行操作
    [[GCDQueue mainQueue] execute:^{
        
        // 初始化3D变换,获取默认值
        CATransform3D perspectiveTransform = CATransform3DIdentity;
        
        // 透视
        perspectiveTransform.m34 = -1.0/500.0;
        
        // 位移
        perspectiveTransform = CATransform3DTranslate(perspectiveTransform, 30, -35, 0);
        
        // 空间旋转
        perspectiveTransform = CATransform3DRotate(perspectiveTransform,
                                                   DEGREES_TO_RADIANS(30), .75, 1, -0.5);
        
        // 缩放变换
        perspectiveTransform = CATransform3DScale(perspectiveTransform, 0.75, 0.75, 0.75);
        
        layer.transform = perspectiveTransform;
        layer.speed = 0.5;
        
    } afterDelay:NSEC_PER_SEC * 6];

    // 9s后执行操作
    [[GCDQueue mainQueue] execute:^{
        
        // 初始化3D变换,获取默认值
        CATransform3D perspectiveTransform = CATransform3DIdentity;
        
        layer.transform = perspectiveTransform;
        layer.speed = 0.5;
        
    } afterDelay:NSEC_PER_SEC * 9];
}


@end

核心代码:

http://stackoverflow.com/questions/3881446/meaning-of-m34-of-catransform3d