hi i have a circle shapeLayer need color by GradientColor
i tried ues CAGradientLayer and mask it like this
let gradientChargeLayer = CAGradientLayer()
gradientChargeLayer.colors = CGColor.mColor
gradientChargeLayer.frame = vShape.bounds
gradientChargeLayer.locations = [0,1]
gradientChargeLayer.startPoint = CGPoint(x: 0,y: 0.5)
gradientChargeLayer.endPoint = CGPoint(x: 1,y: 0.5)
gradientChargeLayer.mask = shapeLayer
vShape.layer.addSublayer(gradientChargeLayer)
but what i want is gradient color from stroke start to end
shapeLayer.path = circularPath.cgPath
shapeLayer.strokeColor = UIColor.red.cgColor <<< here
thanks
you could’ve different approaches I believe
One, you could make an outer and inner circle and then add the required path/layer to the outer circle (this circle bigger than inner) both circles without visible stroke
Or I could recommend you UIGraphigsImageRenderer to work with
https://developer.apple.com/documentation/uikit/uigraphicsimagerenderer
This last have a context that could be used to do more advanced rendering context.cgContext.setStrokePattern here you can add a CGPattern and colors to trying accomplish it
PD. Sorry if my english is confuse
Shape layers only draw in a single color, as I guess you are aware.
By making your shape layer a mask onto a gradient layer you're able to have the shape layer reveal the color of the underlying gradient layer.
If you are always drawing a circle and want the color of the circle's stroke to vary from beginning to end you could set up your gradient layer using a type of conic, and specifying the colors in the gradient layer to begin and end where you want them. However, that would only work for shape layers that contain ovals, where the size and center of the shape and the size and the center of the gradient match.
As #Guillodacosta said in their answer, you may have to give up on using a shape layer and draw your graphic into a graphics context using Core Graphics. (You could do that once and capture the results into a UIImageView to avoid the slowdown of Core Graphics rendering.)
Related
I have a question about drawing half of a UIBezierPath. How do I fill left part (left from thumb) with green color and right part (right from thumb) with white color without using CAGradientLayer?
Code I used to create Bezier Path - https://gist.github.com/robertmryan/67484c74297cede3926a3aed2fceedb9
Screenshot of what I want to achieve:
One approach is to add a mask layer to your curved-path shape layer.
When the "thumb" position changes, change the width of the mask to reveal only the "left-side" of the shape layer.
Create a shape layer to use as the mask:
let maskLayer: CALayer = {
let layer = CALayer()
layer.backgroundColor = UIColor.black.cgColor
return layer
}()
In viewDidLoad() set that layer as the mask for the curved-shape layer:
pathLayer.mask = maskLayer
Whenever the "thumb" position is set, update the width of the mask:
func updateMask(at point: CGPoint) -> Void {
var f = view.bounds
f.size.width = point.x
CATransaction.begin()
CATransaction.setDisableActions(true)
maskLayer.frame = f
CATransaction.commit()
}
I posted a modified version of your gist at: https://gist.github.com/DonMag/a2154e70a3c67193a7b19bee41c8fe95
It really has only a few changes... look for comments beginning with // DonMag -
Here is the result (with an imageView behind it to show the transparency):
Edit
After comments, the goal is to have the "right-side" of the track path be white instead of transparent.
Using the same approach, we can add a white shape layer on top of the original shape layer, and mask it to show only the right-hand-side.
Here is an updated gist - https://gist.github.com/DonMag/397dfbe4779e817531ef7a663365b2e7 - showing this result:
I have a CAShapelayer that's made from a bezier path, but the path is complex and not just a square.
I need to animate the shapelayer fill color to Yellow starting from the bottom of the curve and up (over y axis). (after the layer already attached with the path)
here is the path and layer curve:
If I use this code, it will animate all of the area at once.
let animation = CABasicAnimation(keyPath: "fillColor")
animation.fromValue = UIColor.white.cgColor
animation.toValue = curveFillColor!.cgColor
animation.duration = 4
animation.fillMode = .forwards
animation.isRemovedOnCompletion=false
shapeLayer.add(animation, forKey: "fillColor")
Shape layer code is :
let shapeLayer = CAShapeLayer()
shapeLayer.fillColor = UIColor.yellow.cgColor
shapeLayer.strokeColor = UIColor.yellow.cgColor
shapeLayer.lineWidth = 2.0
shapeLayer.lineJoin = CAShapeLayerLineJoin.round
shapeLayer.lineCap = CAShapeLayerLineCap.round
shapeLayer.strokeStart = 0
shapeLayer.path = path.cgPath
self.layer.addSublayer(shapeLayer)
I think you will probably have to create 2 versions of your shape layer: One filled using the starting color, and one filled with the ending color. Stack them on top of each other with the ending color layer on top. Then mask the ending color layer with a rectangular shape layer mask that has zero height. (meaning that the entire layer is masked.)
Now add an animation that animates the shape layer mask to the full height of your shape layer. That will reveal the ending color layer and cover the starting color layer, creating the effect that the ending color layer paints up from the bottom.
An alternative might be to rework your shape layer so that it that draws from the bottom to the top. To do that I guess you'd create a layer that was composed of a series of vertical lines drawn from bottom to top. Then you could animate the strokeStart or strokeEnd properties of your shape, but transforming your shape into a series of vertical lines would be a pain, and I don't know how you would do that for an arbitrary shape.
I am working on drawing app. I want to implement eraser functionality that erases the path drawn using UIBezierPath.Is it possible??
I have tried below code but its not working
UIGraphicsBeginImageContextWithOptions(self.tempImageView.frame.size, false, 0.0)
if let context = UIGraphicsGetCurrentContext()
{
tempImageView.image?.draw(in: CGRect(x:
0, y: 0, width: self.tempImageView.frame.size.width, height: self.tempImageView.frame.size.height))
let sublayer = CAShapeLayer()
self.tempImageView.layer.addSublayer(sublayer)
context.setBlendMode(CGBlendMode.clear)
sublayer.strokeColor = editorPanelView.drawingColor.cgColor
sublayer.lineJoin = kCALineJoinRound
sublayer.lineCap = kCALineCapRound
sublayer.lineWidth = editorPanelView.brushWidth
let path = UIBezierPath()
path.move(to: CGPoint(x: mid1.x, y: mid1.y))
path.addQuadCurve(to:CGPoint(x:mid2.x, y:mid2.y) , controlPoint: CGPoint(x: prevPoint1.x, y: prevPoint1.y))
sublayer.path = path.cgPath
layerArray.append(sublayer)
UIGraphicsEndImageContext()
}
I am not able to find any solution for this. Any help (even if it's just a kick in the right direction) would be appreciated.
A CAShapeLayer is a vector drawing. It's shapes. The usual eraser tool works with raster (pixel-based) drawings. The two are different, and there isn't a straightforward way to do an eraser tool on vector drawings.
One way you could do it is to have the eraser tool edit a mask layer which is applied to your shape layer. It would have the effect of erasing the parts of the shape layer where the mask is opaque.
One tricky part to this is that once you've drawn into the mask, you'd have to erase that part of the mask in order for the user to be able to draw new content into the erased area, and that might cause the erased parts of the old drawing to show through.
Getting what you want to do to work well would be quite tricky.
I have my program drawing several different CGMutablePaths, each of which belongs to its own CAShapeLayer. It currently looks like this
Notice how the lines of the rectangle overlap the circles. Here is how I want it to look
Essentially, I want the ellipses and their fill to be drawn on top of the lines of the rectangle.
In my code, I have an array of CAShapeLayers, the first of which is the rectangle. In awakeFromNib(), I loop through all the shape layers and update information like the stroke width and fill, then I manually change the fill color of the rectangle to be different. In the draw function, I create all my paths, rectangle first, then ellipses. Finally, I add those paths to their relative shape layer, ellipses after the rectangle.
I have tried swapping the order in each case, but no luck. I honestly can't think of anything else that might be effecting draw order. The strangest part about it is that, in the first image, you'll see that the bottom left ellipse has indeed been drawn above the rectangle, but nowhere in my code is it set apart.
var shapeLayers: [String: CAShapeLayer] = [
"rectangle": CAShapeLayer(),
"ellipse1": CAShapeLayer(),
"ellipse2": CAShapeLayer()...and so on
]
override func awakeFromNib() {
wantsLayer = true
for (_, shapeLayer) in shapeLayers {
shapeLayer.lineWidth = borderWidth
shapeLayer.strokeColor = ColorScheme.blue.cgColor
shapeLayer.fillColor = ColorScheme.white.cgColor
shapeLayer.path = nil
shapeLayer.lineCap = kCALineCapSquare
layer?.addSublayer(shapeLayer)
}
shapeLayers["rectangle"]?.fillColor = NSColor.clear.cgColor
}
override func draw(_ dirtyRect: NSRect) {
let rectangle = CGMutablePath().addRect(selectionBounds)
let ellipse1 = CGMutablePath().addEllipse(in: CGRect(origin: somePoint, size: someSize))
let ellipse2 = CGMutablePath().addEllipse(in: CGRect(origin: somePoint, size: someSize))
...and so on
shapeLayers["rectangle"]?.path = rectangle
shapeLayers["ellipse1"]?.path = ellipse1
shapeLayers["ellipse2"]?.path = ellipse2...and so on
}
I'm clearly missing something basic in my understanding of shapeLayers and paths. Your help is greatly appreciated - TIA
You can use the zPosition to force the layers to draw in a specific order. Just assign them arbitrary values as long as the numbers ascend from back layer to front layer.
I'm trying to draw several shapes (rectangle, triangle, circle, ...) in swift and for that, I use uibezierpath but I am not able to draw exactly what I want.
I need to draw for example a rectangle, but the borders of this rectangle need to have different line width.
To do that, I create different path then use the "appendpath" to merge them in one path. So that works, BUT I also need to have a background image in this rectangle.
For that, I create a layer and set it an image. The issue is that, no background image are displayed when I use "appendpath", certainly because it doesn't recognize my drawing as a rectangle.
I hope it is clear enough, but is there a way to draw a shape with a background image, and have different border width ?
Thanks for your help !!
There are two solutions I'd suggest you try:
1) Masking
Create a normal CALayer and set the image as its contents. Then create a CAShapeLayer with the path you like and use it as the first layer's mask.
E.g.:
let imageLayer = CALayer()
imageLayer.contents = UIImage(named: "yourImage")?.CGImage // Your image here
imageLayer.frame = ... // Define a frame
let maskPath = UIBezierPath(...) // Create your path here
let maskLayer = CAShapeLayer()
maskLayer.path = maskPath.CGPath
imageLayer.mask = maskLayer
Don't forget to set the right frames and paths, and you should be able to achieve the effect you wanted.
2) Fill color
Create a CAShapeLayer with the path you like, then use your image as its fillColor.
E.g.:
let path = UIBezierPath(...) // Create your path here
let layer = CAShapeLayer()
layer.path = path.CGPath
let image = UIImage(named: "yourImage") // Your image here
layer.fillColor = UIColor(patternImage: image!).CGColor
You may find this approach easier at first, but controlling the way the image fills your shape is not trivial at all.
I hope this will help.
If you'd like more details, please provide an image or a sketch of what you're trying to achieve and / or the code you've written so far. Thanks!