Animate transformation from a line to a curve - ios

I encountered a problem when drawing an animated bounce curve.
The code below allow the desired effect animating the line, however when curving i do not want to see the straight line. I had i done wrong with my code ? any comment or guidances are greatly appreciated.
Cheers
- (void)loadView
{
//up Path
upPath = CGPathCreateMutable();
CGPathMoveToPoint(upPath, nil,startingDrawPointX,startingDrawPointY);
CGPathAddQuadCurveToPoint(upPath, nil, controlPoint.x, 100, endingDrawPointX, endingDrawPointY);
CGPathCloseSubpath(upPath);
//down Path
downPath = CGPathCreateMutable();
CGPathMoveToPoint(downPath, nil,startingDrawPointX,startingDrawPointY);
CGPathAddQuadCurveToPoint(downPath, nil, controlPoint.x, 70, endingDrawPointX, endingDrawPointY);
CGPathCloseSubpath(downPath);
//mid Path
midPath = CGPathCreateMutable();
CGPathMoveToPoint(midPath, nil,startingDrawPointX,startingDrawPointY);
CGPathAddQuadCurveToPoint(midPath, nil, controlPoint.x, controlPoint.y, endingDrawPointX, endingDrawPointY);
CGPathCloseSubpath(midPath);
//Create Shape
shapeLayer = [CAShapeLayer layer];
// shapeLayer.path = midPath;
shapeLayer.fillColor = nil;
shapeLayer.strokeColor = kDBrownTextColor.CGColor;
shapeLayer.lineWidth = 2.0;
// shapeLayer.fillRule = kCAFillRuleNonZero;
[self.layer addSublayer:shapeLayer];
[self performSelector:#selector(startAnimation) withObject:nil afterDelay:1.5];
}
-(void)startAnimation
{
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"path"];
animation.duration = 1;
animation.repeatCount = maxCount;
animation.autoreverses = YES;
animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
animation.fromValue = (__bridge id)downPath;
animation.fromValue =(__bridge id)midPath;
animation.toValue = (__bridge id)upPath;
[shapeLayer addAnimation:animation forKey:#"animatePath"];
}

Comment out the lines with CGPathCloseSubpath - they are creating the straight lines you see

Related

CAShapeLayer filling with another CAShapeLayer as a mask

My question is about filling animation one CAShapeLayer with another CAShapeLayer. So, I wrote some code that almost achieves my goal.
I created a based layer and fill it with another. Code below:
- (void)viewDidLoad {
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
_shapeLayer = [CAShapeLayer layer];
[self drawBackgroundLayer];
}
// my main/backgound layer
- (void)drawBackgroundLayer {
_shapeLayer.frame = CGRectMake(0, 0, 250, 250);
_shapeLayer.lineWidth = 3;
_shapeLayer.strokeColor = [UIColor blackColor].CGColor;
_shapeLayer.fillColor = UIColor.whiteColor.CGColor;
_shapeLayer.path = [UIBezierPath bezierPathWithRect:_shapeLayer.bounds].CGPath;
[self.view.layer addSublayer:_shapeLayer];
[self createCircleLayer];
}
Create a circled mask layer for filling:
- (void)createCircleLayer {
_shapeLayer.fillColor = UIColor.greenColor.CGColor;
CAShapeLayer *layer = [CAShapeLayer layer];
CGFloat radius = _shapeLayer.bounds.size.width*sqrt(2)/2;
layer.bounds = CGRectMake(0, 0, 2*radius, 2*radius);
layer.position = CGPointMake(_shapeLayer.bounds.size.width/2, _shapeLayer.bounds.size.height/2);
UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:layer.bounds cornerRadius:radius];
layer.path = path.CGPath;
layer.transform = CATransform3DMakeScale(0.1, 0.1, 1);
_shapeLayer.mask = layer;
}
// our result is next]
So, let's animate it. I just transform the layer to fill the whole "_shapeLayer".
- (void)animateMaskLayer:(CAShapeLayer *)maskLayer {
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"transform"];
animation.toValue = [NSValue valueWithCATransform3D:CATransform3DMakeScale(1, 1, 1.0)];
animation.duration = 1;
animation.removedOnCompletion = NO;
animation.fillMode = kCAFillModeForwards;
[newLayer addAnimation:animation forKey:#"transform"];
}
Now, I want to do the same with this green layer (fill it with red color).
But when I use the mask I have red circle and the white background what is obviously.
My goal here is to have red circle and green background. Like normal filling with another color.
By using inverse mask won't help neither.
So, I just have no ideas how to do it.
If you suggest using:
[_shapeLayer addSublayer:layer];
it won't work as there will be not only square but different paths and clipToBounds is not an option.
Thank you for any help!
So, the solution is simple. I just use two layers and one mask layer.
First layer: Red layer I want to fill with green layer;
- (void)drawBackgroundLayer {
_shapeLayer.frame = CGRectMake(20, 20, 250, 250);
_shapeLayer.lineWidth = 3;
_shapeLayer.strokeColor = [UIColor blackColor].CGColor;
_shapeLayer.lineWidth = 3;
_shapeLayer.fillColor = UIColor.redColor.CGColor;
_shapeLayer.path = [UIBezierPath bezierPathWithRect:_shapeLayer.bounds].CGPath;
[self.view.layer addSublayer:_shapeLayer];
[self drawUpperLayer];
}
Second Layer: Green Layer I use for filling.
- (void)drawUpperLayer {
_upperLayer = [CAShapeLayer layer];
_upperLayer.frame = _shapeLayer.frame;
_upperLayer.lineWidth = 3;
_upperLayer.strokeColor = [UIColor blackColor].CGColor;
_upperLayer.fillColor = UIColor.greenColor.CGColor;
_upperLayer.path = [UIBezierPath bezierPathWithRect:_shapeLayer.bounds].CGPath;
[_shapeLayer.superlayer addSublayer:_upperLayer];
}
Mask Layer:
- (void)createMaskLayer {
CAShapeLayer *layer = [CAShapeLayer layer];
CGFloat radius = _upperLayer.bounds.size.width*sqrt(2)/2;
layer.bounds = CGRectMake(0, 0, 2*radius, 2*radius);
layer.fillColor = UIColor.blackColor.CGColor;
layer.position = CGPointMake(_upperLayer.bounds.size.width/2, _upperLayer.bounds.size.height/2);
UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:layer.bounds cornerRadius:radius];
layer.path = path.CGPath;
layer.transform = CATransform3DMakeScale(0.1, 0.1, 1);
_upperLayer.mask = layer;
}
Animate mask layer:
- (void)animateMaskLayer:(CAShapeLayer *)maskLayer {
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"transform"];
animation.toValue = [NSValue valueWithCATransform3D:CATransform3DMakeScale(1, 1, 1.0)];
animation.duration = 2;
animation.removedOnCompletion = NO;
animation.fillMode = kCAFillModeForwards;
[maskLayer addAnimation:animation forKey:#"transform"];
}
So, resulted animation:

CABasicAnimation + UIBezierPath

I'm trying to create a circular bar such the one that you can find around the recording button in the native camera on iOS when you are doing a timelapse.
A circle is created along the animation, and once it is completed is removed again "naturally".
I tried next code:
CAShapeLayer *circle = [CAShapeLayer layer];
circle.path = [UIBezierPath bezierPathWithArcCenter:CGPointMake(self.lapseBtnOutlet.center.x, self.lapseBtnOutlet.center.y) radius:28 startAngle:2*M_PI*0-M_PI_2 endAngle:2*M_PI*1-M_PI_2 clockwise:YES].CGPath;
circle.fillColor = [UIColor clearColor].CGColor;
circle.strokeColor = [UIColor whiteColor].CGColor;
circle.lineWidth = 2.0;
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"strokeEnd"];
animation.duration = self.lapseInterval;
animation.removedOnCompletion = NO;
animation.fromValue = #(0);
animation.toValue = #(1);
animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear];
[circle addAnimation:animation forKey:#"drawCircleAnimation"];
But my problem now is that I don't know how to "remove" the line from start-to-end.
I tried with autoreverse property, but it removes the circle from end-to-start instead from start-to-end. Any ideas?
You need to animate the strokeStart from 0 to 1, and when the animation finishes, remove the shape layer.
- (void)viewDidLoad {
[super viewDidLoad];
[self performSelector:#selector(animateProperty:) withObject:#"strokeEnd" afterDelay:1];
[self performSelector:#selector(animateProperty:) withObject:#"strokeStart" afterDelay:3];
}
-(void)animateProperty:(NSString *) prop {
if (! self.circle) {
self.circle = [CAShapeLayer layer];
self.circle.path = [UIBezierPath bezierPathWithArcCenter:CGPointMake(self.lapseBtnOutlet.center.x, self.lapseBtnOutlet.center.y) radius:28 startAngle:2*M_PI*0-M_PI_2 endAngle:2*M_PI*1-M_PI_2 clockwise:YES].CGPath;
self.circle.fillColor = [UIColor clearColor].CGColor;
self.circle.strokeColor = [UIColor whiteColor].CGColor;
self.circle.lineWidth = 2.0;
[self.view.layer addSublayer:self.circle];
}
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:prop];
animation.delegate = ([prop isEqualToString:#"strokeStart"])? self : nil;
animation.duration = 1;
animation.removedOnCompletion = NO;
animation.fromValue = #0;
animation.toValue = #1;
[self.circle addAnimation:animation forKey:prop];
}
-(void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag {
[self.circle removeFromSuperlayer];
self.circle = nil;
}

How to animate a curve

I would like to change the curve's Y position which acts like a UISlider with animation.
I have a method drawCurve that will draw a quadCurve, but I would like to animate it. I'm not too sure how I should link it up with CABasicAnimation.
//draw line path
-(void)drawCurve
{
//ensure the drag up or down just in the middle
if (controlPoint.x <= halfWidth || controlPoint.x >= halfWidth) {controlPoint.x = halfWidth;}
if (controlPoint.y <= 0 ) {controlPoint.y = 0;}
if (controlPoint.y >= self.frame.size.height) {controlPoint.y = self.frame.size.height;}
CGContextRef ctx = UIGraphicsGetCurrentContext();
curvePath = CGPathCreateMutable();
CGPathMoveToPoint(curvePath, NULL, startingDrawPointX, startingDrawPointY);
CGPathAddQuadCurveToPoint(curvePath, NULL, controlPoint.x, controlPoint.y, endingDrawPointX, endingDrawPointY);
CGContextAddPath(ctx, curvePath);
CGContextSetStrokeColorWithColor(ctx,kDBrownTextColor.CGColor);
CGContextSetLineWidth(ctx, 2.0);//thickness
CGContextStrokePath(ctx);
CGPathRelease(curvePath);
}
-(void)startAnimation
{
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"path"];
animation.duration = 1;
animation.repeatCount = 5;
animation.autoreverses = NO;
animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
animation.fromValue = (__bridge id)currentCurvePath;
animation.toValue = (__bridge id)ToPath;
[self.layer.superlayer addAnimation:animation forKey:#"animatePath"];
}
Here is an example of what I think your trying to accomplish, using a CAShapeLayer.
+(Class) layerClass {
return [CAShapeLayer class];
}
//draw line path
-(void)drawCurve
{
//ensure the drag up or down just in the middle
if (controlPoint.x <= halfWidth || controlPoint.x >= halfWidth) {controlPoint.x = halfWidth;}
if (controlPoint.y <= 0 ) {controlPoint.y = 0;}
if (controlPoint.y >= self.frame.size.height) {controlPoint.y = self.frame.size.height;}
//create the path
curvePath = CGPathCreateMutable();
CGPathMoveToPoint(curvePath, NULL, startingDrawPointX, startingDrawPointY);
CGPathAddQuadCurveToPoint(curvePath, NULL, controlPoint.x, controlPoint.y, endingDrawPointX, endingDrawPointY);
//add the path to the background layer
CAShapeLayer *layer = (CAShapeLayer *)self.layer;
layer.path = curvePath;
layer.strokeColor = [UIColor brownColor].CGColor;
layer.lineWidth = 2.0;
//release the path
CGPathRelease(curvePath);
}
-(void)startAnimation {
[CATransaction begin];
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"path"];
animation.duration = 1;
animation.repeatCount = 5;
animation.autoreverses = NO;
animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
animation.fromValue = (__bridge id)curvePath;
animation.toValue = (__bridge id)ToPath;
[self.layer addAnimation:animation forKey:#"animatePath"];
[CATransaction commit];
}

CABasicAnimation is not triggered after creation of the layer

I have CALayer subclass. After creation of the layer I want to animate affineTransform of layer but without success. New value is set but the change is not animated. If I trigger the animation after 1 second everything works perfect.
RCLClockDialLayer *layer = [RCLClockDialLayer layer];
layer.frame = CGRectMake(center.x, center.y, 2, self.radius);
layer.center = center;
layer.radius = self.radius;
layer.width = width;
layer.backgroundColor = [UIColor blackColor].CGColor;
layer.color = [UIColor whiteColor];
layer.affineTransform = CGAffineTransformRotate(layer.affineTransform, RCLDegreesToRadians(270));
[self addSubLayer:layer];
CGAffineTransform transform = CGAffineTransformIdentity;
transform = CGAffineTransformRotate(transform, RCLDegreesToRadians(80));
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"affineTransform"];
animation.duration = .5;
animation.fromValue = [layer valueForKey:#"affineTransform"];
animation.toValue = [NSValue valueWithCGAffineTransform:transform];
animation.fillMode = kCAFillModeForwards;
animation.cumulative = YES;
animation.removedOnCompletion = NO;
layer.affineTransform = transform;
[layer addAnimation:animation forKey:#"affineTransform"];
This is my code. I have tried many different solutions but nothing works. Do someone know what is the reason for this?

CABasicAnimation - transform scale keep in center

Trying to animatie an ellipse masked on a UIView to be scale transformed remaining in the center position.
I have found CALayer - CABasicAnimation not scaling around center/anchorPoint, and followed by adding a bounds property to the maskLayer CAShapeLayer however, this ends with the mask being positioned in the left corner with only 1/4 of it showing. I would like the mask to remain within the center of the screen.
#synthesize maskedView;
- (void)viewDidLoad
{
[super viewDidLoad];
UIViewController *vc = [self.storyboard instantiateViewControllerWithIdentifier:#"Next"];
vc.view.frame = CGRectMake(0,0, self.view.frame.size.width, self.view.frame.size.height);
vc.view.layer.bounds = self.view.layer.bounds;
CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
CGRect maskRect = CGRectMake((self.view.frame.size.width/2)-50, (self.view.frame.size.height/2)-50, 100, 100);
CGMutablePathRef path = CGPathCreateMutable();
CGPathAddEllipseInRect(path, nil, maskRect);
[maskLayer setPath:path];
CGPathRelease(path);
vc.view.layer.mask = maskLayer;
[self.view addSubview:vc.view];
maskedView = vc.view;
[self startAnimation];
}
Animation...
-(void)startAnimation
{
maskedView.layer.mask.bounds = CGRectMake((self.view.frame.size.width/2)-50, (self.view.frame.size.height/2)-50, 100, 100);
maskedView.layer.mask.anchorPoint = CGPointMake(.5,.5);
maskedView.layer.mask.contentsGravity = #"center";
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"transform.scale"];
animation.duration = 1.0f;
animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
animation.fromValue = [NSNumber numberWithFloat:1.0f];
animation.toValue = [NSNumber numberWithFloat:5.0f];
[maskedView.layer.mask addAnimation:animation forKey:#"animateMask"];
}
Update
I seem to have fixed this with a second animation on the position key. Is this correct or is there a better way of doing this?
CABasicAnimation *animation2 = [CABasicAnimation animationWithKeyPath:#"position"];
animation2.duration = 1.0f;
animation2.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
animation2.fromValue = [NSValue valueWithCGPoint:CGPointMake((self.view.frame.size.width/2), (self.view.frame.size.height/2))];
animation2.toValue = [NSValue valueWithCGPoint:CGPointMake((self.view.frame.size.width/2), (self.view.frame.size.height/2))];
[toBeMask.layer.mask addAnimation:animation2 forKey:#"animateMask2"];
You can create a scale around the center of the object instead of (0, 0) like this:
CABasicAnimation *scale = [CABasicAnimation animationWithKeyPath:#"transform"];
CATransform3D tr = CATransform3DIdentity;
tr = CATransform3DTranslate(tr, self.bounds.size.width/2, self.bounds.size.height/2, 0);
tr = CATransform3DScale(tr, 3, 3, 1);
tr = CATransform3DTranslate(tr, -self.bounds.size.width/2, -self.bounds.size.height/2, 0);
scale.toValue = [NSValue valueWithCATransform3D:tr];
So we start out with the "identity" transform (which means 'no transform'). Then we translate (move) to the center of the object. Then we scale. Then we move back to origo so we're back where we started (we only wanted to affect the scale operation).
I seem to have fixed this with a second animation on the position key. Is this correct or is there a better way of doing this?
CABasicAnimation *animation2 = [CABasicAnimation animationWithKeyPath:#"position"];
animation2.duration = 1.0f;
animation2.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
animation2.fromValue = [NSValue valueWithCGPoint:CGPointMake((self.view.frame.size.width/2), (self.view.frame.size.height/2))];
animation2.toValue = [NSValue valueWithCGPoint:CGPointMake((self.view.frame.size.width/2), (self.view.frame.size.height/2))];
[toBeMask.layer.mask addAnimation:animation2 forKey:#"animateMask2"];
I am not sure why, but CAShapeLayer does not set the bounds property to the layer. In my case, that's was the problem.
Try setting the bounds. That should work.
I did something like this for building the initial circle
self.circle = [CAShapeLayer layer];
CGRect roundedRect = CGRectMake(0, 0, width, width);
self.circle.bounds = roundedRect;
UIBezierPath *start = [UIBezierPath bezierPathWithRoundedRect:roundedRect cornerRadius:width/2];
[self.circle setPath:start.CGPath];
self.circle.position = CGPointMake(whatever suits you);
self.circleView.layer.mask = self.circle;
[self.circleView.layer.mask setValue: #(1) forKeyPath: #"transform.scale"];
And something like this for scaling it
CABasicAnimation *scale = [CABasicAnimation animationWithKeyPath:#"transform.scale"];
scale.fromValue = [self.circleView.layer.mask valueForKeyPath:#"transform.scale"];
scale.toValue = #(100);
scale.duration = 1.0;
scale.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
[self.circleView.layer.mask setValue:scale.toValue forKeyPath:scale.keyPath];
[self.circleView.layer.mask addAnimation:scale forKey:scale.keyPath];
PD: AnchorPoint is by default (.5,.5) according to apple documentations...but we all know that does not mean anything right?
Hope it helps!!
I have written following function with many added tweaks and options, could be useful for many others.
func layerScaleAnimation(layer: CALayer, duration: CFTimeInterval, fromValue: CGFloat, toValue: CGFloat) {
let timing = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseIn)
let scaleAnimation: CABasicAnimation = CABasicAnimation(keyPath: "transform.scale")
CATransaction.begin()
CATransaction.setAnimationTimingFunction(timing)
scaleAnimation.duration = duration
scaleAnimation.fromValue = fromValue
scaleAnimation.toValue = toValue
layer.add(scaleAnimation, forKey: "scale")
CATransaction.commit()
}
Note: Don't forget to update size after animation completion, because CATransaction reverts back to actual size.

Resources