when I add a gradient color on my view, all of my UI disappear.
I don't know why because it's just the background that I change.
func createGradientLayer() {
let gradientLayer = CAGradientLayer()
gradientLayer.frame = self.view.bounds
gradientLayer.colors = [UIColor().HexToColor(hexString: "#783CBD", alpha: 1).cgColor, UIColor().HexToColor(hexString: "#BC1FFF", alpha: 1).cgColor]
gradientLayer.startPoint = CGPoint(x: 0, y: 0)
gradientLayer.endPoint = CGPoint(x: 1, y: 1)
self.view.layer.addSublayer(gradientLayer)
}
The problem is that method addSublayer by default adds a new view on top of all other views (and hide them).
You need to add sublayer under all other views
self.view.layer.insertSublayer(gradientLayer, at: 0)
Currently I have drawn 2 lines on the screen which are the same color but both have an alpha value less than 1. When these lines intersect, the intersection is a different color than the rest of the lines. There was a previous post addressing the same issue: swift drawing translucent lines, how to make overlapping parts not getting darker? However, this post wasn't sufficiently answered. I draw the lines currently like this:
var points = [CGPoint]()
points = [CGPoint(x: -100, y: 100), CGPoint(x: 100, y: -100)]
let FirstLine = SKShapeNode(points: &points, count: points.count)
FirstLine.strokeColor = UIColor.init(red: 0.25, green: 0.62, blue: 0.0, alpha: 0.5)
FirstLine.lineWidth = 30
addChild(FirstLine)
points = [CGPoint(x: 100, y: 100), CGPoint(x: -100, y: -100)]
let SecondLine = SKShapeNode(points: &points, count: points.count)
SecondLine.strokeColor = UIColor.init(red: 0.25, green: 0.62, blue: 0.0, alpha: 0.5)
SecondLine.lineWidth = 30
addChild(SecondLine)
Here is what it looks like:
I understand why this occurs, but is there any way to make the intersection look the same so it looks much better?
Edit: I have decided to implement #Confused's answer. However, the problem now is that the texture always centres to the middle of the screen. This is an example:
The red cross is in its correct position as it is connecting the specified points together. However, once I make the red cross a texture, it always centres to the middle of the screen (the green cross is the red cross as a texture). Can I use any code that could re-position the texture to its correct position. Note: this code can't just work for this example, I need one that works all the time regardless of the red cross' position.
FINAL EDIT FOR PEOPLE WITH THE SAME PROBLEM
First, setup everything like this:
var points = [CGPoint]()
let crossParent = SKNode()
addChild(crossParent)
Please note THAT YOU MUST create a parent SKNode for the texture otherwise everything on the screen will become the texture and not just the node that you want. Then, add that parent node to the scene.
After, create the lines that you want (in this case the green cross):
//The first line of the green cross
points = [CGPoint(x: -300, y: 300), CGPoint(x: -100, y: 100)]
let FirstLine = SKShapeNode(points: &points, count: points.count)
FirstLine.strokeColor = UIColor.init(red: 0.25, green: 0.62, blue: 0.0, alpha: 1.0)
FirstLine.lineWidth = 30
crossParent.addChild(FirstLine)
Remember to NOT add the first line that you create to the scene, but rather to the parent SKNode that you made at the beginning. Also, set the alpha value to 1.0 for every line that you draw. Then add your other lines:
//The second line of the green cross
points = [CGPoint(x: -100, y: 300), CGPoint(x: -300, y: 100)]
let SecondLine = SKShapeNode(points: &points, count: points.count)
SecondLine.strokeColor = UIColor.init(red: 0.25, green: 0.62, blue: 0.0, alpha: 1.0)
SecondLine.lineWidth = 30
FirstLine.addChild(SecondLine)
Note that you MUST add that line to the first line like this and not to the scene. If you are adding more than one line after adding the first line, then add it to the first line like I have done here too for each consecutive
line that you add.
Now, create the texture like this:
let tex = view?.texture(from: FirstLine)
let cross = SKSpriteNode(texture: tex, color: .clear, size: (tex?.size())!)
cross.alpha = 0.5
addChild(cross)
After doing this, whatever you call cross will be your texture, and you can change the alpha value like I have done here to anything you like and the image will not have varying colors. Remember to then add that texture to the scene.
Finally, you may notice that the texture is not in the same position as where you originally put the points. You can put it back into the same position like this:
cross.position = CGPoint(x: (FirstLine.frame.midX), y: (FirstLine.frame.midY))
Hope this helps :) Thank you to #Confused for the texture part of the program :D
This is a technique. It does not solve your problem, nor directly answer your question. Instead it offers a way to have the desired result, but without the flexibility and inherent nature of lines you actually want.
You can create textures from anything you draw with any number of nodes, with any number of techniques.
You do this (easiest way) by attaching all the drawing elements to a single node, within an SKView space that you have access to, and then render the "parent" node of your drawn objects to a texture.
How does this help?
I'm glad you asked:
You can draw everything at an opacity level of 100%, and render it to a texture, then take that texture of your drawings, put it where you like, and reduce its opacity to any percentage you like, and get an even result. No bright spots where things overlay each other.
Here's code that does all the above:
var points = [CGPoint]()
points = [CGPoint(x: -100, y: 100), CGPoint(x: 100, y: -100)]
let FirstLine = SKShapeNode(points: &points, count: points.count)
FirstLine.strokeColor = UIColor.init(red: 0.25, green: 0.62, blue: 0.0, alpha: 1)
FirstLine.lineWidth = 30
// ^^ Note the FirstLine is not added to the Scene
points = [CGPoint(x: 100, y: 100), CGPoint(x: -100, y: -100)]
let SecondLine = SKShapeNode(points: &points, count: points.count)
SecondLine.strokeColor = UIColor.init(red: 0.25, green: 0.62, blue: 0.0, alpha: 1)
SecondLine.lineWidth = 30
FirstLine.addChild(SecondLine)
// ^^ Note SecondLine being added to FirstLine, and that they both have alpha of 1
// Now the magic: use the view of the SKScene to render FirstLine and its child (SecondLine)
// They are rendered into a texture, named, imaginatively, "tex"
let tex = view.texture(from: FirstLine)
let cross = SKSpriteNode(texture: tex, color: .clear, size: (tex?.size())!)
cross.alpha = 0.5
// ^^ The alpha of the above sprite is set to your original desire of 0.5
// And then added to the scene, with the desired result.
addChild(cross)
and here's the result:
NO! I think is, unfortunately, the answer.
There are the following blend modes, none of which provide the result you're looking for:
case alpha // Blends the source and destination colors by multiplying the source alpha value.
case add // Blends the source and destination colors by adding them up.
case subtract // Blends the source and destination colors by subtracting the source from the destination.
case multiply // Blends the source and destination colors by multiplying them.
case multiplyX2 // Blends the source and destination colors by multiplying them and doubling the result.
case screen // Blends the source and destination colors by multiplying one minus the source with the destination and adding the source.
case replace // Replaces the destination with the source (ignores alpha).
The only option that might work is a custom shader that figures out if it's overlapping itself, somehow. But I have NO CLUE where to even start making something like that, or if it's even possible.
Make the stroke color fully opaque.
Add your path nodes to an SKEffectNode.
Set the alpha of the effect node to the desired value.
Put the effect node into your main scene.
While doing this you can also put all lines in one shape node:
let path = CGMutablePath()
path.move( to: CGPoint(x: -100, y: 100))
path.addLine(to: CGPoint(x: 100, y: -100))
path.move( to: CGPoint(x: 100, y: 100))
path.addLine(to: CGPoint(x: -100, y: -100))
let shape = SKShapeNode(path: path)
shape.strokeColor = UIColor(red: 0.25, green: 0.62, blue: 0.0, alpha: 1)
shape.lineWidth = 30
let effect = SKEffectNode()
effect.addChild(shape)
effect.alpha = 0.5
addChild(effect)
The problem is you are doing the alpha blend at the color level, do the alpha blending at the node level
var points = [CGPoint]()
var cross = SKEffectNode()
points = [CGPoint(x: -100, y: 100), CGPoint(x: 100, y: -100)]
let FirstLine = SKShapeNode(points: &points, count: points.count)
FirstLine.strokeColor = UIColor.init(red: 0.25, green: 0.62, blue: 0.0, alpha: 1)
FirstLine.lineWidth = 30
cross.addChild(FirstLine)
points = [CGPoint(x: 100, y: 100), CGPoint(x: -100, y: -100)]
let SecondLine = SKShapeNode(points: &points, count: points.count)
SecondLine.strokeColor = UIColor.init(red: 0.25, green: 0.62, blue: 0.0, alpha: 1)
SecondLine.lineWidth = 30
cross.addChild(SecondLine)
cross.alpha = 0.5
addChild(cross)
I'm trying to make a semi-transparent window (white), and have a view that sits over the top of it to make it appear clear again.
Essentially, it looks like:
And what I want it to look like is:
My window is defined like:
window!.alphaValue = 0;
// Set level to screensaver level
window!.level = 1000
window!.backgroundColor = NSColor.white;
window!.animator().alphaValue = 0.5;
A white window with 50% opacity. The view on top contains a single CAShapeLayer. This layer is defined like:
shapeLayer = CAShapeLayer();
shapeLayer!.lineWidth = 1.0;
shapeLayer!.strokeColor = NSColor(red: 0.5, green: 0.5, blue: 0.5, alpha: 1).cgColor;
shapeLayer!.fillColor = NSColor(red: 0, green: 0, blue: 0, alpha: 0.5).cgColor;
This window is movable by the user, so I need some kind of dynamic way to clear the contents of the main window and show through to whatever is underneath (the desktop, another application, etc)
I have created a clickable diagram with CAShapeLayers and UIBezierPaths. These shapes have a background-color that I want to fade out to transparent on the sides/edges. All CAShapeLayers have different shapes. Is there a way to achieve this in Swift?
I attached a simple example image of what I'm trying to do:
Right now, I'm creating the CAShapeLayers as follows:
var path = UIBezierPath()
path.moveToPoint(CGPointMake(20, 30))
path.addLineToPoint(CGPointMake(40, 30))
path.addLineToPoint(CGPointMake(50, 60))
path.addLineToPoint(CGPointMake(120, 180))
path.closePath()
var layer = CAShapeLayer()
layer.path = path.CGPath
layer.fillColor = UIColor(red: 255, green: 0, blue: 0, alpha: 0.5).CGColor
layer.hidden = true
baseImg.layer.addSublayer(layer)
Is there a way to add a CIGaussianBlur or a UIBlurEffect to these shapes?
I want the red circle just have the border (no red in centre) and have the rest outside the circle darkened?
I have a issue about that. Could you help me solve it?
With google maps for this, you should do the following steps
Create a GMSCircle object
Set stroke color and fill color for the
circle
Set map for the circle object
Example code:
let circleCenter = CLLocationCoordinate2DMake(9.931233, 76.267303)//change to your center point
let circ = GMSCircle(position: circleCenter, radius: 5000)//radius in meters
circ.fillColor = UIColor(red: 0.35, green: 0, blue: 0, alpha: 0.05)
circ.strokeColor = UIColor.redColor()
circ.strokeWidth = 1
circ.map = mapView //your map view in the UI