0x00 步骤

先读取两张图片把创建出CGImageRef创建上下文画布把图片依次画在画布指定位置上从上下文中获得合并后的图片关闭上下文释放内存

0x01 代码实现

- (void)composeImg {     UIImage *img = [UIImage imageNamed:@"0.png"];     CGImageRef imgRef = img.CGImage;     CGFloat w = CGImageGetWidth(imgRef);     CGFloat h = CGImageGetHeight(imgRef);          //以1.png的图大小为底图     UIImage *img1 = [UIImage imageNamed:@"1.png"];     CGImageRef imgRef1 = img1.CGImage;     CGFloat w1 = CGImageGetWidth(imgRef1);     CGFloat h1 = CGImageGetHeight(imgRef1);          //以1.png的图大小为画布创建上下文     UIGraphicsBeginImageContext(CGSizeMake(w1, h1));     [img1 drawInRect:CGRectMake(0, 0, w1, h1)];//先把1.png 画到上下文中     [img drawInRect:CGRectMake(100, 100, w, h)];//再把小图放在上下文中     UIImage *resultImg = UIGraphicsGetImageFromCurrentImageContext();//从当前上下文中获得最终图片     UIGraphicsEndImageContext();//关闭上下文          NSString *path = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject];     NSString *filePath = [path stringByAppendingPathComponent:@"01.png"];     [UIImagePNGRepresentation(resultImg) writeToFile:filePath atomically:YES];//保存图片到沙盒 CGImageRelease(imgRef);     CGImageRelease(imgRef1); }

0x10 效果图

转载于:https://www.cnblogs.com/LeeYZ/p/5167418.html

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