Unit icon alpha control (#7343)

* Unit icon alpha/size control

Implemented sliders in Options -> Display to give user control over unit icon opacity and size.

* Simplified sliders and re-added idle 50% transparency

* Minor fixes from PR review

* Removed unit icon size adjustment

android/assets/jsons/translations/template.properties

@@ -697,6 +697,7 @@ Show pixel units =
 Show pixel improvements = 
 Enable Nuclear Weapons = 
 Experimental Demographics scoreboard = 
+Unit icon opacity = 
 Show zoom buttons in world screen = 
 Enable display cutout (requires restart) = 
 Show tile yields = 

core/src/com/unciv/models/metadata/GameSettings.kt

@@ -45,6 +45,7 @@ class GameSettings {
 
     var showMinimap: Boolean = true
     var minimapSize: Int = 6    // default corresponds to 15% screen space
+    var unitIconOpacity = 1f // default corresponds to fully opaque
     var showPixelUnits: Boolean = true
     var showPixelImprovements: Boolean = true
     var continuousRendering = false

core/src/com/unciv/ui/options/DisplayTab.kt

@@ -42,6 +42,8 @@ fun displayTab(
 
     addMinimapSizeSlider(this, settings, optionsPopup.selectBoxMinWidth)
 
+    addUnitIconAlphaSlider(this, settings, optionsPopup.selectBoxMinWidth)
+
     addResolutionSelectBox(this, settings, optionsPopup.selectBoxMinWidth, onResolutionChange)
 
     addTileSetSelectBox(this, settings, optionsPopup.selectBoxMinWidth, onTilesetChange)
@@ -94,6 +96,25 @@ private fun addMinimapSizeSlider(table: Table, settings: GameSettings, selectBox
     table.add(minimapSlider).minWidth(selectBoxMinWidth).pad(10f).row()
 }
 
+private fun addUnitIconAlphaSlider(table: Table, settings: GameSettings, selectBoxMinWidth: Float) {
+    table.add("Unit icon opacity".toLabel()).left().fillX()
+
+    val getTipText: (Float) -> String = {"%.0f".format(it*100) + "%"}
+
+    val unitIconAlphaSlider = UncivSlider(
+        0f, 1f, 0.1f, initial = settings.unitIconOpacity, getTipText = getTipText
+    ) {
+        settings.unitIconOpacity = it
+        settings.save()
+
+        val worldScreen = UncivGame.Current.getWorldScreenIfActive()
+        if (worldScreen != null)
+            worldScreen.shouldUpdate = true
+
+    }
+    table.add(unitIconAlphaSlider).minWidth(selectBoxMinWidth).pad(10f).row()
+}
+
 private fun addResolutionSelectBox(table: Table, settings: GameSettings, selectBoxMinWidth: Float, onResolutionChange: () -> Unit) {
     table.add("Resolution".toLabel()).left().fillX()
 

core/src/com/unciv/ui/tilegroups/TileGroupIcons.kt

@@ -66,6 +66,7 @@ class TileGroupIcons(val tileGroup: TileGroup) {
 
         if (unit != null && isViewable) { // Tile is visible
             newImage = UnitGroup(unit, 25f)
+
             if (UncivGame.Current.settings.continuousRendering && oldUnitGroup?.blackSpinningCircle != null) {
                 newImage.blackSpinningCircle = ImageGetter.getCircle()
                         .apply { rotation = oldUnitGroup.blackSpinningCircle!!.rotation }
@@ -99,13 +100,18 @@ class TileGroupIcons(val tileGroup: TileGroup) {
                 newImage.addActor(holder)
             }
 
+            newImage.unitBaseImage.color.a = UncivGame.Current.settings.unitIconOpacity //0f (invisible) to 1f (fully opaque)
+            newImage.actionGroup?.color?.a = UncivGame.Current.settings.unitIconOpacity //0f (invisible) to 1f (fully opaque)
+
             // Instead of fading out the entire unit with its background, we just fade out its central icon,
             // that way it remains much more visible on the map
             if (!unit.isIdle() && unit.civInfo == viewingCiv) {
-                newImage.unitBaseImage.color.a = 0.5f
+                newImage.unitBaseImage.color.a *= 0.5f
-                newImage.actionGroup?.color?.a = 0.5f
+                newImage.actionGroup?.color?.a = 0.5f * UncivGame.Current.settings.unitIconOpacity
             }
+
         }
+
         return newImage
     }
 

core/src/com/unciv/ui/utils/UnitGroup.kt

@@ -16,11 +16,13 @@ class UnitGroup(val unit: MapUnit, val size: Float): Group() {
     var actionGroup :Group? = null
     val unitBaseImage = ImageGetter.getUnitIcon(unit.name, unit.civInfo.nation.getInnerColor())
         .apply { setSize(size * 0.75f, size * 0.75f) }
+    var background: Image? = null
 
     init {
-        val background = getBackgroundImageForUnit()
+        background = getBackgroundImageForUnit()
-        background.apply {
+        background?.apply {
             this.color = unit.civInfo.nation.getOuterColor()
+            this.color.a = UncivGame.Current.settings.unitIconOpacity
             setSize(size, size)
         }
         setSize(size, size)
@@ -68,6 +70,11 @@ class UnitGroup(val unit: MapUnit, val size: Float): Group() {
 
 
     fun selectUnit() {
+
+        //Make unit icons fully opaque when units are selected
+        unitBaseImage.color.a = 1f
+        background?.color?.a = 1f
+
         val whiteHalo = getBackgroundImageForUnit()
         val whiteHaloSize = 30f
         whiteHalo.setSize(whiteHaloSize, whiteHaloSize)
@@ -75,6 +82,7 @@ class UnitGroup(val unit: MapUnit, val size: Float): Group() {
         addActor(whiteHalo)
         whiteHalo.toBack()
 
+
         if (UncivGame.Current.settings.continuousRendering) {
             val spinningCircle = if (blackSpinningCircle != null) blackSpinningCircle!!
             else ImageGetter.getCircle()