Shadows not working with Mask type.

[Abdul-Moiz]

I am trying to apply shadow on Mask type Circle seems like it's not working. Removing mask working properly.

[JakeLin]

@Abdul-Moiz I introduced this bug when I fixed another bug #180 , I am looking at how can we fix it.

[JakeLin]

@Abdul-Moiz I have tried to fix this issue, please have a look at the commit 3c5bc85

But the effect is not right, it is not easy to fix it. If you have time, can you have a look and let me know if you find anything? Thanks

If you want to apply a shadow to a Circle, there is a workaround, you can set cornerRadius = width / 2.

[Abdul-Moiz]

@JakeLin I tried to look into the issue. Somehow the shadow is clipping within the view bounds.
The approach I can think of to fix it is adding sublayer below main layer. And avoid the masking completely.

For time being going with the workaround 2.

[JakeLin]

@Abdul-Moiz thanks for looking at it. As you said, I think we need to have two layers. And apply the mask to shadowPath of the second layer. Would you like to give it a go with a PR when you have time? Please let me know if you are interested.

[Abdul-Moiz]

@JakeLin This is the code that made the shadow render correctly on the view with masking. I didn't tested all the cases but working fine for AnimatableView, Button and image.

public func configMaskShadow() {
    commonSetup()
    // if a layer mask is specified, display the shadow to match the mask
    if let mask = layer.mask as? CAShapeLayer {
      // Clear default layer borders
      layer.shadowColor = nil
      layer.shadowRadius = 0
      layer.shadowOpacity = 0

      // Remove any previous layer
      layer.superlayer?.sublayers?.filter { $0.name == "shadowLayer-\(unsafeAddressOf(self))" }
        .forEach { $0.removeFromSuperlayer() }

      // Create new layer with object's memory reference to make this string unique. Otherwise common name will remove all the shadow layers as it's adding in layer's superview.
      let shadowLayer = CAShapeLayer()
      shadowLayer.name = "shadowLayer-\(unsafeAddressOf(self))"
      shadowLayer.frame = frame

      // Configure shadow properties
      if let unwrappedShadowColor = shadowColor {
        shadowLayer.shadowColor = unwrappedShadowColor.CGColor
      }
      if !shadowRadius.isNaN && shadowRadius > 0 {
        shadowLayer.shadowRadius = shadowRadius
      }
      if !shadowOpacity.isNaN && shadowOpacity >= 0 && shadowOpacity <= 1 {
        shadowLayer.shadowOpacity = Float(shadowOpacity)
      }
      if !shadowOffset.x.isNaN {
        shadowLayer.shadowOffset.width = shadowOffset.x
      }
      if !shadowOffset.y.isNaN {
        shadowLayer.shadowOffset.height = shadowOffset.y
      }
      shadowLayer.shadowPath = mask.path

      // Add to layer's superview in order to render shadow otherwise it will clip out due to mask layer.
      layer.superlayer?.insertSublayer(shadowLayer, below: layer)
    }
  }

[JakeLin]

@Abdul-Moiz thanks, looks very good. The solution should be fine. I am busy on preparing a presentation for Dev World will have a deep look later.

[JakeLin]

@Abdul-Moiz Sorry for the late action, I have submitted a PR #295 to address this issue, please have a look when you have time. Thanks for fixing this issue.