Mapbox GL plugin + ShaderEffect

[loiczimmermann]

Hi,

I'm experiencing some quite weired issues when using mapboxgl plugin with ShaderEffect. The opacity is not applied on the layer.

Here is the QML object I try to display on the map:

import QtQuick 2.12
import QtGraphicalEffects 1.0

import QtLocation 5.15

MapItemGroup {
	MapItemView {
		id: list
		anchors.fill: parent
		model: mySegmentModel

		delegate: MapPolyline{
                       path: model.points
	               line.width: 2
	               line.color: model.color
		}
	}

	ShaderEffectSource {
		height: parent.height
		width: parent.width
		sourceItem: list
		opacity: 0.3
		hideSource: true
	}
}

If I apply the opacity directly on the MapPolyline, it works well but as all polylines can cross each other, I got some bad effect. Furhermore with old mapbox plugin it was working correctly.