I am trying to draw a piece of pie in SCNShape using the following code:
UIBezierPath *piePiece = [UIBezierPath bezierPath];
[piePiece addArcWithCenter: CGPointZero radius: 0.150 startAngle: 0.0 endAngle: M_PI/6 clockwise: YES];
[piePiece closePath];
SCNShape *pieShape = [SCNShape shapeWithPath: piePiece extrusionDepth: 0];
pieShape.firstMaterial.diffuse.contents = [UIColor blueColor];
pieShape.firstMaterial.doubleSided = YES;
SCNNode *pieNode = [SCNNode nodeWithGeometry: pieShape];
But I get the following shape:
Sample
I don't see the arc. What am I doing wrong?
Thanks
You must change the flatness of the UIBezierPath to a lower value. In Swift:
pieShape.flatness = 0.0003
Related
I am using a UIBezierPath to draw a curved line. The curve works however, I am unable to curve the edges of the line.
If you look at the top/bottom end of the curve, you can see that the edges are flattened out, thats not what I want. Is there a way to curve the edges?
I am using a simple UIBezierPath to draw an (almost) semi circle. This creates the curved line shape that I want:
CAShapeLayer *circle = [CAShapeLayer layer];
circle.path = [UIBezierPath bezierPathWithArcCenter:CGPointMake(0, 0) radius:70 startAngle:1.0472 endAngle:5.23599 clockwise:NO].CGPath;
circle.fillColor = [UIColor clearColor].CGColor;
circle.strokeColor = [UIColor colorWithWhite:1.0 alpha:0.2].CGColor;
circle.lineWidth = 18.0;
circle.cornerRadius = 10.0;
circle.position = CGPointMake(100, 100);
circle.anchorPoint = CGPointMake(0.5, 0.5);
[mainView.layer addSublayer:circle];
Despite setting the cornerRadius property, the corners are not curved. What am I doing wrong?
Thanks for your time, Dan.
Include the following.
circle.lineCap = kCALineJoinRound;
For Swift 3.0 and above
circle.lineCapStyle = .Round;
Swift 4.0
circle.lineCap = kCALineCapRound
and if you want your lines intersections to also be rounded set
circle.lineJoin = kCALineCapRound
as well.
I'm using CAShapeLayer to draw a semicircle and I want to have a kCGLineCapRound at the start and a kCGLineCapButt at the end. How can I do that?
UIBezierPath *circlePathMax = [UIBezierPath bezierPathWithArcCenter:CGPointMake(self.view.center.x, self.view.center.y) radius:radius startAngle:angle1 endAngle:angle2 clockwise:YES];
CAShapeLayer *circleMax;
circleMax = [CAShapeLayer layer];
circleMax.path = circlePathMax.CGPath;
circleMax.lineCap = kCALineCapRound;
circleMax.fillColor = [UIColor clearColor].CGColor;
circleMax.lineWidth = 10;
circleMax.strokeColor = [UIColor colorWithRed:255.0/255.0f green:255.0f/255.0f blue:255.0f/255.0f alpha:0.7f].CGColor;
circleMax.zPosition = 3;
[self.view.layer addSublayer:circleMax];
I can specify only one generic lineCap
You could use lineCap .butt, and at the end of your semicircle, draw yourself a circle.
This is the trick I used. In my case I had to draw a semicircle with transparency on top of an imageView of a gradient semicircle. This allowed me to use .butt with the background color (with alpha component) as strokeColor to "hide" the squared corners.
let circleMin = CAShapeLayer.init()
let circlePathMin = UIBezierPath.init(arcCenter: myCenter, radius: myRadius, startAngle: startingAngle, endAngle: endingAngle, clockwise: true)
circleMin.path = circlePathMin.cgPath
circleMin.lineCap = .butt
circleMin.fillColor = UIColor.clear.cgColor
circleMin.lineWidth = 14
circleMin.strokeColor = self.containerView.backgroundColor?.withAlphaComponent(0.7).cgColor
circleMin.zPosition = 3
containerView.layer.addSublayer(circleMin)
In questions like How to draw a smooth circle..., ...Draw Circle... and ...draw filled Circles the question and answer is very broad, contains lots of unnecessary steps and the methods used isn't always the easiest to re-create or manage.
What is an easy way to draw a circle and add it to my UIView?
An easy way to draw a circle is to create a CAShapeLayer and add a UIBezierPath.
objective-c
CAShapeLayer *circleLayer = [CAShapeLayer layer];
[circleLayer setPath:[[UIBezierPath bezierPathWithOvalInRect:CGRectMake(50, 50, 100, 100)] CGPath]];
swift
let circleLayer = CAShapeLayer();
circleLayer.path = UIBezierPath(ovalIn: CGRect(x: 50, y: 50, width: 100, height: 100)).cgPath;
After creating the CAShapeLayer we set its path to be a UIBezierPath.
Our UIBezierPath then draws a bezierPathWithOvalInRect. The CGRect we set will effect its size and position.
Now that we have our circle, we can add it to our UIView as a sublayer.
objective-c
[[self.view layer] addSublayer:circleLayer];
swift
view.layer.addSublayer(circleLayer)
Our circle is now visible in our UIView.
If we wish to customise our circle's color properties we can easily do so by setting the CAShapeLayer's stroke- and fill color.
objective-c
[circleLayer setStrokeColor:[[UIColor redColor] CGColor]];
[circleLayer setFillColor:[[UIColor clearColor] CGColor]];
swift
shapeLayer.strokeColor = UIColor.red.cgColor;
shapeLayer.fillColor = UIColor.clear.cgColor;
Additionall properties can be found over at 's documentation on the subject https://developer.apple.com/.../CAShapeLayer_class/index.html.
Using CAShapeLayer Class makes drawing easy...
1.Create CAShapeLayer Object
2.Create a Circular path
3.Set the path to the wanted CAShapeLayer path
4.Add the layer to your view
let shapeLayer = CAShapeLayer()
let center = view.center
let circulPath = UIBezierPath(arcCenter: center, radius: 100, startAngle: 0, endAngle: 2.0 * CGFloat.pi, clockwise: true)
shapeLayer.path = circulPath.cgPath
view.layer.addSublayer(shapeLayer)
Note That ,here I draw the circle from center of the view.
You can also set the fill color for your circle like bellow:
shapeLayer.fillColor = UIColor.red.cgColor
for further study you can check on
CALayer.com
I try to change a circle into a square and vice versa and I am almost there. However it doesn't animates as expected. I would like all corners of a square to be animated/morphed at the same time but what I get is the following:
I use CAShapeLayer and CABasicAnimation in order to animate shape property.
Here is how I create the circle path:
- (UIBezierPath *)circlePathWithCenter:(CGPoint)center radius:(CGFloat)radius
{
UIBezierPath *circlePath = [UIBezierPath bezierPath];
[circlePath addArcWithCenter:center radius:radius startAngle:0 endAngle:M_PI/2 clockwise:YES];
[circlePath addArcWithCenter:center radius:radius startAngle:M_PI/2 endAngle:M_PI clockwise:YES];
[circlePath addArcWithCenter:center radius:radius startAngle:M_PI endAngle:3*M_PI/2 clockwise:YES];
[circlePath addArcWithCenter:center radius:radius startAngle:3*M_PI/2 endAngle:M_PI clockwise:YES];
[circlePath closePath];
return circlePath;
}
Here is the square path:
- (UIBezierPath *)squarePathWithCenter:(CGPoint)center size:(CGFloat)size
{
CGFloat startX = center.x-size/2;
CGFloat startY = center.y-size/2;
UIBezierPath *squarePath = [UIBezierPath bezierPath];
[squarePath moveToPoint:CGPointMake(startX, startY)];
[squarePath addLineToPoint:CGPointMake(startX+size, startY)];
[squarePath addLineToPoint:CGPointMake(startX+size, startY+size)];
[squarePath addLineToPoint:CGPointMake(startX, startY+size)];
[squarePath closePath];
return squarePath;
}
I apply the circle path to one of my View's layers, set the fill etc. It draws perfectly.
Then in my gestureRecognizer selector I create and run the following animation:
CABasicAnimation *animation = [CABasicAnimation animationWithKeyPath:#"path"];
animation.duration = 1;
animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
animation.fromValue = (__bridge id)(self.stateLayer.path);
animation.toValue = (__bridge id)(self.stopPath.CGPath);
self.stateLayer.path = self.stopPath.CGPath;
[self.stateLayer addAnimation:animation forKey:#"animatePath"];
As you can notice in the circlePathWithCenter:radius: and squarePathWithCenter:size: I follow the suggestion from here (to have the same number of segments and control points):
Smooth shape shift animation
The animation looks better then in the post from above but it is still not the one I want to achieve :(
I know that I can do it with simple CALayer and then set appropriate level of cornerRadius to make a circle out of square/rectangle and after that animate cornerRadius property to change it from circle to square but I'm still extremaly curious if it is even possible to do it with CAShapeLayer and path animation.
Thanks in advance for help!
After playing with it for a little while in the playground I noticed that each arc adds two segments to the bezier path, not just one. Moreover, calling closePath adds two more. So to keep the number of segments consistent, I ended up with adding fake segments to my square path. The code is in Swift, but I think it doesn't matter.
func circlePathWithCenter(center: CGPoint, radius: CGFloat) -> UIBezierPath {
let circlePath = UIBezierPath()
circlePath.addArcWithCenter(center, radius: radius, startAngle: -CGFloat(M_PI), endAngle: -CGFloat(M_PI/2), clockwise: true)
circlePath.addArcWithCenter(center, radius: radius, startAngle: -CGFloat(M_PI/2), endAngle: 0, clockwise: true)
circlePath.addArcWithCenter(center, radius: radius, startAngle: 0, endAngle: CGFloat(M_PI/2), clockwise: true)
circlePath.addArcWithCenter(center, radius: radius, startAngle: CGFloat(M_PI/2), endAngle: CGFloat(M_PI), clockwise: true)
circlePath.closePath()
return circlePath
}
func squarePathWithCenter(center: CGPoint, side: CGFloat) -> UIBezierPath {
let squarePath = UIBezierPath()
let startX = center.x - side / 2
let startY = center.y - side / 2
squarePath.moveToPoint(CGPoint(x: startX, y: startY))
squarePath.addLineToPoint(squarePath.currentPoint)
squarePath.addLineToPoint(CGPoint(x: startX + side, y: startY))
squarePath.addLineToPoint(squarePath.currentPoint)
squarePath.addLineToPoint(CGPoint(x: startX + side, y: startY + side))
squarePath.addLineToPoint(squarePath.currentPoint)
squarePath.addLineToPoint(CGPoint(x: startX, y: startY + side))
squarePath.addLineToPoint(squarePath.currentPoint)
squarePath.closePath()
return squarePath
}
I know this is an old question but this might help someone.
I think its better to animate corner radius to get this effect.
let v1 = UIView(frame: CGRect(x: 100, y: 100, width: 50, height: 50))
v1.backgroundColor = UIColor.green
view.addSubview(v1)
animation:
let animation = CABasicAnimation(keyPath: "cornerRadius")
animation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionLinear)
animation.fillMode = kCAFillModeForwards
animation.isRemovedOnCompletion = false
animation.fromValue = v1.layer.cornerRadius
animation.toValue = v1.bounds.width/2
animation.duration = 3
v1.layer.add(animation, forKey: "cornerRadius")
Based on #Danchoys answer, here it is for Objective-C.
info is a button of 60px and infoVC is the next ViewController being pushed:
UIBezierPath * maskPath = [UIBezierPath new];
[maskPath addArcWithCenter:info.center radius:15.0f startAngle:DEGREES_TO_RADIANS(180) endAngle:DEGREES_TO_RADIANS(270) clockwise:true];
[maskPath addArcWithCenter:info.center radius:15.0f startAngle:DEGREES_TO_RADIANS(270) endAngle:DEGREES_TO_RADIANS(0) clockwise:true];
[maskPath addArcWithCenter:info.center radius:15.0f startAngle:DEGREES_TO_RADIANS(0) endAngle:DEGREES_TO_RADIANS(90) clockwise:true];
[maskPath addArcWithCenter:info.center radius:15.0f startAngle:DEGREES_TO_RADIANS(90) endAngle:DEGREES_TO_RADIANS(180) clockwise:true];
[maskPath closePath];
UIBezierPath * endPath = [UIBezierPath new];
[endPath moveToPoint:CGPointMake(0,0)];
[endPath addLineToPoint:endPath.currentPoint];
[endPath addLineToPoint:CGPointMake(w, 0)];
[endPath addLineToPoint:endPath.currentPoint];
[endPath addLineToPoint:CGPointMake(w, h)];
[endPath addLineToPoint:endPath.currentPoint];
[endPath addLineToPoint:CGPointMake(0, h)];
[endPath addLineToPoint:endPath.currentPoint];
[endPath closePath];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame = info.bounds;
maskLayer.path = maskPath.CGPath;
_infoVC.view.layer.mask = maskLayer;
CABasicAnimation * animation = [CABasicAnimation animationWithKeyPath:#"path"];
animation.fromValue = (id)maskPath.CGPath;
animation.toValue = (id)endPath.CGPath;
animation.duration = 0.3f;
[maskLayer addAnimation:animation forKey:nil];
[maskLayer setPath:endPath.CGPath];
I can highly recommend the library CanvasPod, it also has a predefined "morph" animation and is easy to integrate. You can also check out examples on the website canvaspod.io.
This is handy for people making a recording button and want a native iOS like animation.
Instantiate this class within the UIViewController you would like to have the button. Add a UITapGestureRecogniser and call animateRecordingButton when tapped.
import UIKit
class RecordButtonView: UIView {
enum RecordingState {
case ready
case recording
}
var currentState: RecordingState = .ready
override init(frame: CGRect) {
super.init(frame: frame)
self.isUserInteractionEnabled = true
self.backgroundColor = .white
// My button is 75 points in height and width so this
// Will make a circle
self.layer.cornerRadius = 35
}
required init?(coder: NSCoder) {
super.init(coder: coder)
}
func animateRecordingButton() {
var newRadius: CGFloat
var scale: CGFloat
switch currentState {
case .ready:
// The square radius
newRadius = 10
// Lets scale it down to 70%
scale = 0.7
currentState = .recording
case .recording:
// Animate back to cirlce
newRadius = 35
currentState = .ready
// Animate back to full scale
scale = 1
}
UIView.animate(withDuration: 1) {
self.layer.cornerRadius = newRadius
self.transform = CGAffineTransform(scaleX: scale, y: scale)
}
}
}
I am trying to draw a view with few hollow circles in it. The view background color will be black with opacity 0.5 and hollow circles on places where I could see the view underneath it. This is working fine with below piece of code but has an issue when my hollow circles intersects, I want to cover both of them as hollow area but due to even odd rule this is not working out. Any suggestions?
Or any alternatives?
- (void)addShadowView {
UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(0, 0, self.bounds.size.width, self.bounds.size.height) cornerRadius:0];
for (NSValue *point in self.hollowFrames) {
UIBezierPath *circlePath = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(point.CGPointValue.x - self.hollowCircleRadius.floatValue, point.CGPointValue.y - self.hollowCircleRadius.floatValue, 2.0 * self.hollowCircleRadius.floatValue, 2.0 * self.hollowCircleRadius.floatValue) cornerRadius:self.hollowCircleRadius.floatValue];
[path appendPath:circlePath];
}
[path setUsesEvenOddFillRule:YES];
CAShapeLayer *fillLayer = [CAShapeLayer layer];
fillLayer.path = path.CGPath;
fillLayer.fillRule = kCAFillRuleEvenOdd;
fillLayer.fillColor = [UIColor blackColor].CGColor;
fillLayer.opacity = 0.5;
[self.layer addSublayer:fillLayer];
}
This is how it looks right now. I want the intersected area also to be hollow and not filled with the fillColor.
don't fill the circles, clip out the centers.