我尝试在其超级视图中旋转图像视图，以便旋转时此图像视图始终接触超级视图的边界而不跨越它们，并进行适当的调整大小。我该如何实施？图像视图应该能够围绕 360° 旋转。
在这里，我使用基于三角形公式的计算，考虑到初始图像视图对角线角度。
也许我应该考虑旋转后图像视图的新边界框（它的 x 和 y 坐标变为负数，变换后的帧大小也变大）。
到目前为止没有成功，我的图像视图被缩小得太快而且太多了。因此，据我所知，我的目标是为CGAffineTransformScale. 也许还有其他方法可以做到这一点。
// set initial values
_planImageView.layer.affineTransform = CGAffineTransformScale(CGAffineTransformIdentity, 1, 1);
_degrees = 0;
_initialWidth = _planImageView.frame.size.width;
_initialHeight = _planImageView.frame.size.height;
_initialAngle = MathUtils::radiansToDegrees(atan((_initialWidth / 2) / (_initialHeight / 2)));
// rotation routine
- (void)rotatePlanWithDegrees:(double)degrees
{
double deltaDegrees = degrees - _degrees;
_initialAngle -= deltaDegrees;
double newAngle = _initialAngle;
double newWidth = (_initialWidth / 2) * tan(MathUtils::degreesToRadians(newAngle)) * 2;
double newHeight = newWidth * (_initialHeight / _initialWidth);
NSLog(@"DEG %f DELTA %f A %f W %f H %f", degrees, deltaDegrees, newAngle, newWidth, newHeight);
double currentScale = newWidth / _initialWidth;
_planImageView.layer.affineTransform = CGAffineTransformScale(CGAffineTransformIdentity, currentScale, currentScale);
_planImageView.layer.affineTransform = CGAffineTransformRotate(_planImageView.layer.affineTransform, (CGFloat) MathUtils::degreesToRadians(degrees));
_degrees = degrees;
self->_planImageView.center = _center;
// NSLog(@"%@", NSStringFromCGRect(_planImageView.frame));
}
编辑
由于答案，我覆盖了常规，现在它可以工作了！
- (void)rotatePlanWithDegrees:(double)degrees
{
double newWidth =
_initialWidth * abs(cos(MathUtils::degreesToRadians(degrees))) +
_initialHeight * abs(sin(MathUtils::degreesToRadians(degrees)));
double newHeight =
_initialWidth * abs(sin(MathUtils::degreesToRadians(degrees))) +
_initialHeight * abs(cos(MathUtils::degreesToRadians(degrees)));
CGFloat scale = (CGFloat) MIN(
self.planImageScrollView.frame.size.width / newWidth,
self.planImageScrollView.frame.size.height / newHeight);
CGAffineTransform rotationTransform = CGAffineTransformMakeRotation((CGFloat) MathUtils::degreesToRadians(degrees));
CGAffineTransform scaleTransform = CGAffineTransformMakeScale(scale, scale);
_planImageView.layer.affineTransform = CGAffineTransformConcat(rotationTransform, scaleTransform);
self->_planImageView.center = _center;
}