獲取嵌套在UIScrollView中的UIImageView中兩個CGPoint之間的距離

Question

CGRect screenSize = [[UIScreen mainScreen]bounds]; 
CGFloat screenWidth = screenSize.size.width; 
CGRect visibleRect; 
    visibleRect.origin = scrollView.contentOffset; 
    visibleRect.size = imageView.frame.size; 
    CGPoint midPoint = CGPointMake(visibleRect.origin.x + visibleRect.size.width/2, visibleRect.origin.y + visibleRect.size.height/2); 
CGPoint place = CGPointMake(class.xValue, class.yValue); 

xValue和yValue是'int'在類中聲明的。

-(int)distanceFrom:(CGPoint)point1 to:(CGPoint)point2{ 
CGFloat xDist = ((point2.x) - (point1.x)); 
CGFloat yDist = ((point2.y) - (point1.y)); 
return (sqrt((xDist * xDist) + (yDist * yDist))); 
} 

的問題是，一旦通過我在應用中滾動改變zoomScale調出方法的數急劇變化（〜1000個像素）。如何考慮zoomScale？在此先感謝， 亞歷克斯

Answer 1

當您放大時，距離方法的結果乘以滾動視圖的zoomScale。如果你想得到實際的距離，嘗試除以滾動視圖的zoomScale的距離。