Reduce the effect of noise on power flow direction visualisation

We visualise the direction of power flow with an icon and a colour
e.g. feed-in icon with green colour gauge, versus grid-draw icon
     with blue colour gauge.

This commit ensures that we don't flicker between feed-in and
grid-draw visualisation if the value is actually zero and the
readings are just noise, by requiring that the power value
exceeds a certain magnitude before we recognise it.

Contributes to #1328

components/SideMultiGauge.qml

@@ -47,12 +47,14 @@ Item {
 		delegate: Item {
 			id: gaugeDelegate
 
-			readonly property bool feedingToGrid: root.inputMode
-					&& (model.power || 0) < 0
-
 			width: Theme.geometry_briefPage_edgeGauge_width
 			height: root.height
 
+			// ignore noise values (close to zero)
+			readonly property real modelValue: Math.floor(Math.abs(model[root.phaseModelProperty] || 0)) < 1.0 ? 0.0
+					: model[root.phaseModelProperty]
+			readonly property bool feedingToGrid: root.inputMode && modelValue < 0.0
+
 			SideGauge {
 				id: gauge
 				animationEnabled: root.animationEnabled
@@ -93,7 +95,7 @@ Item {
 				// reverses the gauge direction so that negative and positive values have the same
 				// value on the gauge, though negative values will be drawn in green.
 				value: root.visible
-					   ? (gaugeDelegate.feedingToGrid ? Math.abs(model[root.phaseModelProperty]) : model[root.phaseModelProperty])
+					   ? (gaugeDelegate.feedingToGrid ? Math.abs(gaugeDelegate.modelValue) : gaugeDelegate.modelValue)
 					   : root.minimumValue
 				minimumValue: 0
 				maximumValue: Math.max(Math.abs(root.minimumValue), Math.abs(root.maximumValue))

components/ThreePhaseBarGauge.qml

@@ -32,9 +32,16 @@ Flow {
 		id: phaseRepeater
 
 		delegate: Item {
+			id: phaseDelegate
+
 			width: root.orientation === Qt.Vertical ? root.width : root._delegateLength
 			height: root.orientation === Qt.Vertical ? root._delegateLength : root.height
 
+			// ignore noise values (close to zero)
+			readonly property real modelValue: Math.floor(Math.abs(model[root.phaseModelProperty] || 0)) < 1.0 ? 0.0
+					: model[root.phaseModelProperty]
+			readonly property bool feedingToGrid: root.inputMode && modelValue < 0.0
+
 			Label {
 				id: phaseLabel
 
@@ -53,7 +60,7 @@ Flow {
 				// reverses the gauge direction so that negative and positive values have the same
 				// value on the gauge, though negative values will be drawn in green.
 				value: root.visible
-					   ? gaugeLoader.feedingToGrid ? Math.abs(model[root.phaseModelProperty]) : model[root.phaseModelProperty]
+					   ? phaseDelegate.feedingToGrid ? Math.abs(phaseDelegate.modelValue) : phaseDelegate.modelValue
 					   : root.minimumValue
 				minimumValue: 0
 				maximumValue: Math.max(Math.abs(root.minimumValue), Math.abs(root.maximumValue))
@@ -65,15 +72,13 @@ Flow {
 				width: parent.width - (phaseLabel.visible ? phaseLabel.width : 0)
 				height: parent.height
 				sourceComponent: Global.isGxDevice ? cheapGauge : prettyGauge
-				readonly property bool feedingToGrid: root.inputMode
-						&& (model.power || 0) < 0
 			}
 
 			Component {
 				id: cheapGauge
 				CheapBarGauge {
-					foregroundColor: Theme.color_darkOk,gaugeLoader.feedingToGrid ? Theme.color_green : Theme.statusColorValue(valueStatus)
-					backgroundColor: Theme.color_darkOk,gaugeLoader.feedingToGrid ? Theme.color_darkGreen
+					foregroundColor: Theme.color_darkOk,phaseDelegate.feedingToGrid ? Theme.color_green : Theme.statusColorValue(valueStatus)
+					backgroundColor: Theme.color_darkOk,phaseDelegate.feedingToGrid ? Theme.color_darkGreen
 							: root.inOverviewWidget && valueStatus === Theme.Ok ? Theme.color_darkishBlue
 							: Theme.statusColorValue(valueStatus, true)
 					valueType: root.valueType
@@ -86,8 +91,8 @@ Flow {
 			Component {
 				id: prettyGauge
 				BarGauge {
-					foregroundColor: Theme.color_darkOk,gaugeLoader.feedingToGrid ? Theme.color_green : Theme.statusColorValue(valueStatus)
-					backgroundColor: Theme.color_darkOk,gaugeLoader.feedingToGrid ? Theme.color_darkGreen
+					foregroundColor: Theme.color_darkOk,phaseDelegate.feedingToGrid ? Theme.color_green : Theme.statusColorValue(valueStatus)
+					backgroundColor: Theme.color_darkOk,phaseDelegate.feedingToGrid ? Theme.color_darkGreen
 							: root.inOverviewWidget && valueStatus === Theme.Ok ? Theme.color_darkishBlue
 							: Theme.statusColorValue(valueStatus, true)
 					valueType: root.valueType

components/ThreePhaseDisplay.qml

@@ -34,7 +34,10 @@ Flow {
 		delegate: Item {
 			id: phaseDelegate
 
-			readonly property bool feedingToGrid: root.inputMode && (model.power || 0) < 0
+			// ignore noise values (close to zero)
+			readonly property real modelValue: Math.floor(Math.abs(model[root.phaseModelProperty] || 0)) < 1.0 ? 0.0
+					: model[root.phaseModelProperty]
+			readonly property bool feedingToGrid: root.inputMode && modelValue < 0.0
 			readonly property int valueStatus: feedingToGrid ? Theme.Ok
 					: root.phaseModelProperty ? Theme.getValueStatus(valueRange.valueAsRatio * 100, root.valueType)
 					: Theme.Ok
@@ -82,7 +85,7 @@ Flow {
 			ValueRange {
 				id: valueRange
 
-				value: root.phaseModelProperty ? model[root.phaseModelProperty] : 0
+				value: phaseDelegate.modelValue
 				minimumValue: root.minimumValue
 				maximumValue: root.maximumValue
 			}

data/common/AcInputPhaseModel.qml

@@ -9,7 +9,7 @@ import Victron.VenusOS
 ListModel {
 	id: root
 
-	property int totalPower
+	property real totalPower
 	property real firstPhaseCurrent: count === 1 ? get(0).current : NaN
 
 	readonly property Timer _timer: Timer { // timer needed so the display doesn't update too frequently

data/common/ActiveAcInput.qml

@@ -18,15 +18,14 @@ Device {
 	readonly property int source: !!inputInfo ? inputInfo.source : VenusOS.AcInputs_InputSource_NotAvailable
 	readonly property alias gensetStatusCode: _acInputService.gensetStatusCode
 
-	readonly property real power: _phases.totalPower
+	// clamp to zero any values with magnitude < 1 (assume it's noise) to avoid UI flicker.
+	readonly property real power: (Math.floor(Math.abs(_phases.totalPower)) < 1.0) ? 0.0 : _phases.totalPower
 	readonly property real current: phases.count === 1 ? _phases.firstPhaseCurrent : NaN // multi-phase systems don't have a total current
 	readonly property alias currentLimit: _acInputService.currentLimit
 	readonly property alias phases: _phases
 
 	// Phase measurements from com.victronenergy.system/Ac/ActiveIn/L<1|2|3>
-	readonly property AcInputPhaseModel _phases: AcInputPhaseModel {
-		id: _phases
-	}
+	readonly property AcInputPhaseModel _phases: AcInputPhaseModel { id: _phases }
 
 	// Data from the input-specific service, e.g. com.victronenergy.vebus for a VE.Bus input,
 	// or com.victronenergy.grid for grid parallel systems.