Pixel unit colors based on civilization colors (#3231)

* Enabled Pixel Unit colors based on civilization colors

* Strict pattern for image layers

* Updated docstring

* Reworked layers' retrieval

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

@@ -53,9 +53,9 @@ open class TileGroup(var tileInfo: TileInfo, var tileSetStrings:TileSetStrings)
     protected var naturalWonderImage: Image? = null
 
     protected var pixelMilitaryUnitImageLocation = ""
-    protected var pixelMilitaryUnitImage: Image? = null
+    protected var pixelMilitaryUnitGroup = Group().apply { isTransform = false; setSize(groupSize, groupSize) }
     protected var pixelCivilianUnitImageLocation = ""
-    protected var pixelCivilianUnitImage: Image? = null
+    protected var pixelCivilianUnitGroup = Group().apply { isTransform = false; setSize(groupSize, groupSize) }
 
     val miscLayerGroup = Group().apply { isTransform = false; setSize(groupSize, groupSize) }
     var resourceImage: Actor? = null
@@ -93,6 +93,9 @@ open class TileGroup(var tileInfo: TileInfo, var tileSetStrings:TileSetStrings)
         this.addActor(cityButtonLayerGroup)
         this.addActor(circleCrosshairFogLayerGroup)
 
+        terrainFeatureLayerGroup.addActor(pixelMilitaryUnitGroup)
+        terrainFeatureLayerGroup.addActor(pixelCivilianUnitGroup)
+
         updateTileImage(null)
 
         addCircleImage()
@@ -597,15 +600,16 @@ open class TileGroup(var tileInfo: TileInfo, var tileSetStrings:TileSetStrings)
         }
 
         if (pixelMilitaryUnitImageLocation != newImageLocation) {
-            pixelMilitaryUnitImage?.remove()
+            pixelMilitaryUnitGroup.clear()
-            pixelMilitaryUnitImage = null
             pixelMilitaryUnitImageLocation = newImageLocation
 
             if (newImageLocation != "" && ImageGetter.imageExists(newImageLocation)) {
-                val pixelUnitImage = ImageGetter.getImage(newImageLocation)
+                val nation = militaryUnit!!.civInfo.nation
-                terrainFeatureLayerGroup.addActor(pixelUnitImage)
+                val pixelUnitImages = ImageGetter.getLayeredImageColored(newImageLocation, null, nation.getInnerColor(), nation.getOuterColor())
-                setHexagonImageSize(pixelUnitImage)// Treat this as A TILE, which gets overlayed on the base tile.
+                for (pixelUnitImage in pixelUnitImages) {
-                pixelMilitaryUnitImage = pixelUnitImage
+                    pixelMilitaryUnitGroup.addActor(pixelUnitImage)
+                    setHexagonImageSize(pixelUnitImage)// Treat this as A TILE, which gets overlayed on the base tile.
+                }
             }
         }
     }
@@ -613,9 +617,10 @@ open class TileGroup(var tileInfo: TileInfo, var tileSetStrings:TileSetStrings)
 
     fun updatePixelCivilianUnit(tileIsViewable: Boolean) {
         var newImageLocation = ""
+        val civilianUnit = tileInfo.civilianUnit
 
-        if (tileInfo.civilianUnit != null && tileIsViewable) {
+        if (civilianUnit != null && tileIsViewable) {
-            val specificUnitIconLocation = tileSetStrings.unitsLocation + tileInfo.civilianUnit!!.name
+            val specificUnitIconLocation = tileSetStrings.unitsLocation + civilianUnit.name
             newImageLocation = when {
                 !UncivGame.Current.settings.showPixelUnits -> ""
                 ImageGetter.imageExists(specificUnitIconLocation) -> specificUnitIconLocation
@@ -624,15 +629,16 @@ open class TileGroup(var tileInfo: TileInfo, var tileSetStrings:TileSetStrings)
         }
 
         if (pixelCivilianUnitImageLocation != newImageLocation) {
-            pixelCivilianUnitImage?.remove()
+            pixelCivilianUnitGroup.clear()
-            pixelCivilianUnitImage = null
             pixelCivilianUnitImageLocation = newImageLocation
 
             if (newImageLocation != "" && ImageGetter.imageExists(newImageLocation)) {
-                val pixelUnitImage = ImageGetter.getImage(newImageLocation)
+                val nation = civilianUnit!!.civInfo.nation
-                terrainFeatureLayerGroup.addActor(pixelUnitImage)
+                val pixelUnitImages = ImageGetter.getLayeredImageColored(newImageLocation, null, nation.getInnerColor(), nation.getOuterColor())
-                setHexagonImageSize(pixelUnitImage)// Treat this as A TILE, which gets overlayed on the base tile.
+                for (pixelUnitImage in pixelUnitImages) {
-                pixelCivilianUnitImage = pixelUnitImage
+                    pixelCivilianUnitGroup.addActor(pixelUnitImage)
+                    setHexagonImageSize(pixelUnitImage)// Treat this as A TILE, which gets overlayed on the base tile.
+                }
             }
         }
     }

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

@@ -67,6 +67,61 @@ object ImageGetter {
         }
     }
 
+
+    /**
+     * Colors a multilayer image and returns it as a list of layers (Image).
+     *
+     * @param   baseFileName    The filename of the base image.
+     *                              For example: TileSets/FantasyHex/Units/Warrior
+     *
+     * @param   colors          The list of colors, one per layer. No coloring is applied to layers
+     *                              whose color is null.
+     *
+     * @return  The list of layers colored. The layers are sorted by NUMBER (see example below) order
+     *              and colors are applied, one per layer, in the same order. If a color is null, no
+     *              coloring is performed on such layer (it stays as it is). If there are less colors
+     *              than layers, the last layers are not colored. Defaults to an empty list if there
+     *              is no layer corresponding to baseFileName.
+     *
+     * Example:
+     *      getLayeredImageColored("TileSets/FantasyHex/Units/Warrior", null, Color.GOLD, Color.RED)
+     *
+     *      All images in the atlas that match the pattern "TileSets/FantasyHex/Units/Warrior" or
+     *      "TileSets/FantasyHex/Units/Warrior-NUMBER" are retrieved. NUMBERs must start from 1 and
+     *      be incremented by 1 per layer. If the n-th NUMBER is missing, the (n-1)-th layer is the
+     *      last one retrieved:
+     *      Given the layer names:
+     *          - TileSets/FantasyHex/Units/Warrior
+     *          - TileSets/FantasyHex/Units/Warrior-1
+     *          - TileSets/FantasyHex/Units/Warrior-2
+     *          - TileSets/FantasyHex/Units/Warrior-4
+     *      Only the base layer and layers 1 and 2 are retrieved.
+     *      The method returns then a list in which first layer has unmodified colors, the second is
+     *      colored in GOLD and the third in RED.
+     */
+    fun getLayeredImageColored(baseFileName: String, vararg colors: Color?): ArrayList<Image> {
+        if (!imageExists(baseFileName))
+            return arrayListOf()
+
+        val layerNames = mutableListOf(baseFileName)
+        val layerList = arrayListOf<Image>()
+
+        var i = 1
+        while (imageExists("$baseFileName-$i")) {
+            layerNames.add("$baseFileName-$i")
+            ++i
+        }
+
+        for (i in layerNames.indices) {
+            val image = getImage(layerNames[i])
+            if (i < colors.size && colors[i] != null)
+                image.color = colors[i]
+            layerList.add(image)
+        }
+
+        return layerList
+    }
+
     /*fun refreshAtlas() {
         atlas.dispose() // To avoid OutOfMemory exceptions
         atlas = TextureAtlas("game.atlas")