Adjusting the line to fit our head in imageview

问题

I am developing one application same as HairTryOn all things are done. but problem is display in following image. i want to set hair style as per customer face using blue line as per display in image. i used the following code

    testVw = [[UIView alloc]initWithFrame:CGRectMake(100,100, 100, 100)];
    testVw.backgroundColor = [UIColor clearColor];
    [self.view addSubview:testVw];    


    resizeVw = [[UIImageView    alloc]initWithFrame:CGRectMake(testVw.frame.size.width-25, testVw.frame.size.height-25, 25, 25)];
    resizeVw.backgroundColor = [UIColor clearColor];
    resizeVw.userInteractionEnabled = YES;
    resizeVw.image = [UIImage imageNamed:@"button_02.png" ];

    [testVw addSubview:resizeVw];

    UIPanGestureRecognizer* panResizeGesture = [[UIPanGestureRecognizer alloc] 
    initWithTarget:self action:@selector(resizeTranslate:)];

    [testVw addGestureRecognizer:panResizeGesture];

The resizeTranslate: method:

-(void)resizeTranslate:(UIPanGestureRecognizer *)recognizer
{
        if ([recognizer state]== UIGestureRecognizerStateBegan) 
        {
            prevPoint = [recognizer locationInView:testVw.superview];
            [testVw setNeedsDisplay];
        }
        else if ([recognizer state] == UIGestureRecognizerStateChanged)
        {
            if (testVw.bounds.size.width < 20)
            {

                testVw.bounds = CGRectMake(testVw.bounds.origin.x, testVw.bounds.origin.y, 20,testVw.bounds.size.height);
                imgvw.frame = CGRectMake(12, 12, testVw.bounds.size.width-24, testVw.bounds.size.height-27);
                resizeVw.frame =CGRectMake(testVw.bounds.size.width-25, testVw.bounds.size.height-25, 25, 25);
                rotateVw.frame = CGRectMake(0, testVw.bounds.size.height-25, 25, 25);
                closeVw.frame = CGRectMake(0, 0, 25, 25);            
            }

            if(testVw.bounds.size.height < 20)
            {
                testVw.bounds = CGRectMake(testVw.bounds.origin.x, testVw.bounds.origin.y, testVw.bounds.size.width, 20);
                imgvw.frame = CGRectMake(12, 12, testVw.bounds.size.width-24, testVw.bounds.size.height-27);
                resizeVw.frame =CGRectMake(testVw.bounds.size.width-25, testVw.bounds.size.height-25, 25, 25);
                rotateVw.frame = CGRectMake(0, testVw.bounds.size.height-25, 25, 25);
                closeVw.frame = CGRectMake(0, 0, 25, 25);
            }

            CGPoint point = [recognizer locationInView:testVw.superview];
            float wChange = 0.0, hChange = 0.0;

            wChange = (point.x - prevPoint.x); //Slow down increment
            hChange = (point.y - prevPoint.y); //Slow down increment 


            testVw.bounds = CGRectMake(testVw.bounds.origin.x, testVw.bounds.origin.y, testVw.bounds.size.width + (wChange), testVw.bounds.size.height + (hChange));
            imgvw.frame = CGRectMake(12, 12, testVw.bounds.size.width-24, testVw.bounds.size.height-27);

            resizeVw.frame =CGRectMake(testVw.bounds.size.width-25, testVw.bounds.size.height-25, 25, 25);
            rotateVw.frame = CGRectMake(0, testVw.bounds.size.height-25, 25, 25);
            closeVw.frame = CGRectMake(0, 0, 25, 25);

            prevPoint = [recognizer locationInView:testVw.superview];

            [testVw setNeedsDisplay];
    }
    else if ([recognizer state] == UIGestureRecognizerStateEnded)
    {
        prevPoint = [recognizer locationInView:testVw.superview];
        [testVw setNeedsDisplay];
    }
}

This code Resizing full view. but i want to Resize only those part which is moved by finger.

回答1:

I don't see how your primitives are constructed. But you will need to partition your point set according to touch zones and scale then as needed. If you convert your lines into Bezier curves, then manipulating the curve will be easier, as you will not need to do terrible amount of adjustment to the shape with a small modifications.

来源：https://stackoverflow.com/questions/15402377/adjusting-the-line-to-fit-our-head-in-imageview