I've created a dashed CAShapeLayer using the code below. The line draws correctly when its path is on a perfectly horizontal plane. However as soon as the path moves up or down, the line suffers from some issues. See the images as an example.
CGMutablePathRef linePath = CGPathCreateMutable();
CGPathMoveToPoint(linePath, NULL, startShapeLayer.centerX, startShapeLayer.centerY);
CGPathAddLineToPoint(linePath, NULL, endShapeCenter.x, endShapeCenter.y);
CGPathCloseSubpath(linePath);
CAShapeLayer *lineLayer = [CAShapeLayer layer];
lineLayer.path = linePath;
lineLayer.fillColor = [UIColor clearColor].CGColor;
lineLayer.strokeColor = [UIColor whiteColor].CGColor;
lineLayer.lineCap = kCALineCapRound;
lineLayer.lineDashPattern = #[#5, #5];
lineLayer.lineDashPhase = 5.0;
lineLayer.lineWidth = 1.0;
If anyone has some advice about drawing these kinds of shapes it'd be great to hear.
Related
My problem is following: I'm trying to cut out a segment out of custom UIView and apply a shadow effect to this view.
In a custom UIView class, I did this:
Created two layers - shadow and mask. Added a shadow layer as a sublayer for this custom view. Then I created a new view, set its mask as the mask layer and added it as a subview to the custom view.
self.backgroundColor = [UIColor clearColor];
CGFloat radius = 40;
float startAngle = -M_PI;
float endAngle = 0;
UIBezierPath *path = [UIBezierPath bezierPathWithRect:self.bounds];
[path moveToPoint:CGPointMake(CGRectGetMidX(self.bounds), CGRectGetMaxY(self.bounds)+radius/1.8)];
[path addArcWithCenter:CGPointMake(CGRectGetMidX(self.bounds), CGRectGetMaxY(self.bounds)+radius/1.8) radius:radius startAngle:startAngle endAngle:endAngle clockwise:YES];
CAShapeLayer *shadowLayer = [[CAShapeLayer alloc] init];
shadowLayer.frame = self.bounds;
shadowLayer.path = path.CGPath;
shadowLayer.shadowColor = [UIColor grayColor].CGColor;
shadowLayer.shadowOpacity = 0.5;
shadowLayer.shadowRadius = 2;
shadowLayer.masksToBounds = NO;
shadowLayer.shadowOffset = CGSizeMake(2.0, 2.0);
shadowLayer.fillRule = kCAFillRuleEvenOdd;
CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
maskLayer.frame = self.bounds;
maskLayer.masksToBounds = NO;
maskLayer.path = path.CGPath;
maskLayer.fillRule = kCAFillRuleEvenOdd;
maskLayer.fillColor = [UIColor whiteColor].CGColor;
[self.layer addSublayer:shadowLayer];
UIView *view = [[UIView alloc] initWithFrame:self.bounds];
view.backgroundColor = [UIColor whiteColor];
view.layer.mask = maskLayer;
[self addSubview:view];
That is what I want to achieve -
and this is what I actually get
If I set clipToBounds = YES, it will cut off the desired shadow effect.
There would be absolutely no problem, if I wanted to cut of a semicircle. Because in this case the semicircle path fully sits inside of view bounds.
But I do need to achieve a result shown in the first image.
I was thinking about building the path line by line, but the problem occurs when it comes to this arc, and the result will probably not be so accurate.
Does anyone have ideas how it could be done?
Thank you!
EDIT:
If the issue is that the path is wrong, do no composite the path in code using a circle and guessing the coordinates. Instead you should export the coordinates actual artwork and use the artwork coordinates for the curve. It looks like you have a sketch file so the easiest way to do this is to copy and paste into paint code which will give you the code for the curve, but in the event you don't have paint code (you should, its amazing for this kind of stuff) you can export the curve as SVG from sketch. If you open the resulting SVG in a text editor you will see its in human readable XML and you can extract the control points from your Bezier curve from there.
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.
So I'm trying to cut a circle out of an existing layer; and here's my code:
CGRect bounds = _containerLayer.bounds;
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame = bounds;
maskLayer.fillColor = [UIColor blackColor].CGColor;
CGFloat smallCircleRadius = (frame.size.width - barWidth)/2;
CGRect smallCircleRect = CGRectMake(CGRectGetMidX(bounds) - smallCircleRadius, CGRectGetMidY(bounds) - smallCircleRadius, 2 * smallCircleRadius, 2 * smallCircleRadius);
UIBezierPath *circlePath = [UIBezierPath bezierPathWithOvalInRect:smallCircleRect];
[circlePath appendPath:[UIBezierPath bezierPathWithRect:bounds]];
maskLayer.path = circlePath.CGPath;
maskLayer.fillRule = kCAFillRuleEvenOdd;
_containerLayer.mask = maskLayer;
This code does work, as I now see a black rectangle with a hollow circle in the middle. But the problem is that when I tried to set maskLayer.fillColor = [UIColor clearColor].CGColor;, The whole thing including _containerLayer just disappears - I want to make the fillColor transparent so I can see what's originally in the _containerLayer (which wasn't cut out). What should I do to achieve this? Thanks!
I am not able to display rounded caps on my Arc created using UIBezierPath. It's still perfectly squared regardless I set kCGLineCapRound or not.
This topic should be same as this one, however solution is not working.
Here is the example code I have in viewWillAppear (for test purposes only):
int radius = 100;
CAShapeLayer *arc = [CAShapeLayer layer];
UIBezierPath *path = [UIBezierPath bezierPathWithArcCenter:CGPointMake(100, 50) radius:radius startAngle:M_PI endAngle:M_PI/150 clockwise:YES];
path.lineCapStyle = kCGLineCapRound;
arc.path = path.CGPath;
arc.position = CGPointMake(CGRectGetMidX(self.view.frame)-radius, CGRectGetMidY(self.view.frame)-radius);
arc.fillColor = [UIColor clearColor].CGColor;
arc.strokeColor = [UIColor purpleColor].CGColor;
arc.lineWidth = 10.0f;
arc.cornerRadius = 3.0f;
Here is how it looks:
I am helpless so I would appreciate any help. Thanks guys.
Use the lineCap property of the CAShapeLayer rather than the lineCapStyle of the path.
arc.lineCap = kCALineCapRound;
If you are calling the path's stroke method (e.g. if you're doing this in drawRect or manually drawing in a UIGraphicsContext) then set attributes like the cap or join styles in the UIBezierPath. But when using CAShapeLayer, the attributes are set on the shape layer, not the path.
I want to create a mask layer which is a circle that makes the circle content transparent and keep everything around. Unfortunately, the following code does the opposite, it draws a circle and make everything around transparent.
CAShapeLayer * shape = [CAShapeLayer layer];
shape.frame = CGRectMake((CGSSize().width/2.f)-40.f, -40.f, 80.f, 80.f);
CGPathRef pathRef =
CGPathCreateWithEllipseInRect(CGRectMakeBoundsWithSize(shape.frame.size), NULL);
shape.path = pathRef;
shape.fillColor = [UIColor blueColor].CGColor;
self.layer.mask = shape;
Yeah, kCAFillRuleEvenOdd didn't do it's magic without adding a rect first, here is a working snippet though:
CAShapeLayer *shape = [CAShapeLayer layer];
shape.frame = self.bounds;
CGMutablePathRef pathRef = CGPathCreateMutable();
CGPathAddRect(pathRef, NULL, self.bounds);
CGPathAddEllipseInRect(pathRef, NULL, self.bounds);
shape.fillRule = kCAFillRuleEvenOdd;
shape.path = pathRef;
self.layer.mask = shape;