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获取CGAffineTransform xcode中的缩放值和旋转值

cgaffinetransform uiimage xcode ios

Alvin John Tandoc · 技术社区 · 10 年前

我正在开发一个应用程序,用户可以在上面捏和旋转图像。捏紧并旋转图像后。必须打印图像。我想得到我的图像的缩放因子和旋转因子,这样我就可以绘制新图像,然后打印新图像。但我的问题是我无法获得图像的缩放和旋转因子。有人能教我如何使用CGAffineTransform获得缩放因子和旋转因子吗。或者有人可以教我如何在缩放和旋转后保存图像。非常感谢你们。这是我的密码。

- (void)rotationImage:(UIRotationGestureRecognizer*)gesture {
    [self.view bringSubviewToFront:gesture.view];

    if ([gesture state] == UIGestureRecognizerStateEnded) {
        lastRotation = 0;
        return;
    }
    CGAffineTransform currentTransform = img_tempImage.transform;
    CGFloat rotation = 0.0 - (lastRotation - gesture.rotation);
    CGAffineTransform newTransform = CGAffineTransformRotate(currentTransform, rotation);
    img_tempImage.transform = newTransform;
    myTransform = img_tempImage.transform;
    lastRotation = gesture.rotation;
    isTransform = YES;

}

- (void)pinchImage:(UIPinchGestureRecognizer*)pinchGestureRecognizer {
    [self.view bringSubviewToFront:pinchGestureRecognizer.view];
    pinchGestureRecognizer.view.transform = CGAffineTransformScale(pinchGestureRecognizer.view.transform, pinchGestureRecognizer.scale, pinchGestureRecognizer.scale);
    pinchGestureRecognizer.scale = 1;
    myTransform = img_tempImage.transform;
    isTransform = YES;
}

- (void)panpan:(UIPanGestureRecognizer *)sender {
    [self.view bringSubviewToFront:img_tempImage];
    CGPoint translation = [sender translationInView:self.view];
    CGPoint imageViewPosition = img_tempImage.center;
    imageViewPosition.x += translation.x;
    imageViewPosition.y += translation.y;
    myPoint = imageViewPosition;
    img_tempImage.center = imageViewPosition;
    [sender setTranslation:CGPointZero inView:self.view];
}

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
    return  YES;
}

1 回复 | 直到 10 年前

Alvin John Tandoc 10 年前

我找到了关于如何获得刻度和旋转值的问题的答案。

 CGFloat angle = [(NSNumber *)[img_tempImage valueForKeyPath:@"layer.transform.rotation.z"] floatValue];
    NSLog(@"by angle: %.2f",angle);
    CGFloat xScale = img_tempImage.transform.a;
    CGFloat yScale = img_tempImage.transform.d;
    NSLog(@"xScale :%.2f",xScale);
    NSLog(@"yScale :%.2f",yScale);