Add city centre icon to minimap

README.md

@@ -11,3 +11,6 @@ This [techdemo](https://www.youtube.com/watch?v=feEMmo1pRSY&feature=youtu.be) pr
 ![sc2](/images/niceCity5.jpg)
 
 This module originates from the GSOC 2016 Project Citysimulation by [CptCrispyCrunchy](https://github.com/CptCrispyCrunchy) with [Skaldarnar](https://github.com/skaldarnar) and [msteiger](https://github.com/msteiger) as mentors.
+
+### Images
+The building icon image was taken from http://www.iconsmind.com (Linkware License)

src/main/java/org/terasology/dynamicCities/minimap/CentreOverlay.java

@@ -0,0 +1,120 @@
+/*
+ * Copyright 2019 MovingBlocks
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.terasology.dynamicCities.minimap;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.terasology.dynamicCities.settlements.SettlementsCacheComponent;
+import org.terasology.entitySystem.entity.EntityRef;
+import org.terasology.logic.location.LocationComponent;
+import org.terasology.math.geom.Rect2f;
+import org.terasology.math.geom.Rect2fTransformer;
+import org.terasology.math.geom.Rect2i;
+import org.terasology.math.geom.Vector2f;
+import org.terasology.math.geom.Vector2i;
+import org.terasology.minimap.overlays.MinimapOverlay;
+import org.terasology.rendering.assets.texture.Texture;
+import org.terasology.rendering.nui.Canvas;
+import org.terasology.utilities.Assets;
+
+import java.util.Optional;
+
+public class CentreOverlay implements MinimapOverlay {
+
+    private EntityRef settlementCachingEntity;
+    private Logger logger = LoggerFactory.getLogger(DistrictOverlay.class);
+
+    private Vector2f iconSize = new Vector2f(32f, 32f);
+
+
+    public CentreOverlay(EntityRef entityRef) {
+        this.settlementCachingEntity = entityRef;
+    }
+
+    @Override
+    public void render(Canvas canvas, Rect2f worldRect) {
+        if (!settlementCachingEntity.hasComponent(SettlementsCacheComponent.class)) {
+            logger.error("No SettlementCacheComponent found!");
+            return;
+        }
+
+        Rect2f screenRect = Rect2f.createFromMinAndSize(
+                new Vector2f(canvas.getRegion().minX(), canvas.getRegion().minY()),
+                new Vector2f(canvas.getRegion().maxX(), canvas.getRegion().maxY())
+        );
+
+        Rect2fTransformer transformer = new Rect2fTransformer(worldRect, screenRect);
+
+        for (EntityRef settlement : settlementCachingEntity.getComponent(SettlementsCacheComponent.class).settlementEntities.values()) {
+            if (!settlement.isActive()) {
+                continue;
+            }
+            LocationComponent locationComponent = settlement.getComponent(LocationComponent.class);
+            if (locationComponent == null) {
+                logger.error("Cannot find location component for settlement: " + settlement.toString());
+                return;
+            }
+
+            Vector2f location = new Vector2f(locationComponent.getLocalPosition().x(), locationComponent.getLocalPosition().z());
+            Vector2f mapPoint = new Vector2f(
+                    transformer.applyX(location.x),
+                    transformer.applyY(location.y)
+            );
+
+            Vector2i min = clamp(mapPoint, screenRect);
+            Rect2i region = Rect2i.createFromMinAndSize(min.x, min.y, (int) iconSize.x, (int) iconSize.y);
+
+            Optional<Texture> icon = Assets.getTexture("DynamicCities:city-icon");
+            if (icon.isPresent()) {
+                canvas.drawTexture(icon.get(), region);
+            } else {
+                logger.error("No icon found for city");
+            }
+        }
+    }
+
+    private Vector2i clamp(Vector2f point, Rect2f box) {
+        float x;
+        float y;
+        Rect2f iconRegion = Rect2f.createFromMinAndSize(point, iconSize);
+        if (box.contains(iconRegion)) {
+            return new Vector2i(point.x, point.y);
+        } else {
+            if (iconRegion.maxX() >= box.maxX()) {
+                x = (int) box.maxX() - iconSize.x;
+            } else if (iconRegion.minX() <= box.minX()) {
+                x = (int) box.minX();
+            } else {
+                x = point.x;
+            }
+
+            if (iconRegion.maxY() >= box.maxY()) {
+                y = (int) box.maxY() - iconSize.y;
+            } else if (iconRegion.minY() <= box.minY()) {
+                y = (int) box.minY();
+            } else {
+                y = point.y;
+            }
+        }
+        return new Vector2i(x, y);
+    }
+
+    @Override
+    public int getZOrder() {
+        return 0;
+    }
+
+}

src/main/java/org/terasology/dynamicCities/minimap/DistrictOverlaySystem.java → src/main/java/org/terasology/dynamicCities/minimap/MinimapOverlaySystem.java

@@ -18,6 +18,7 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.terasology.dynamicCities.minimap.events.AddCentreOverlayEvent;
 import org.terasology.dynamicCities.minimap.events.AddDistrictOverlayEvent;
 import org.terasology.dynamicCities.minimap.events.RemoveDistrictOverlayEvent;
 import org.terasology.dynamicCities.settlements.SettlementsCacheComponent;
@@ -39,7 +40,7 @@
 import java.util.Map;
 
 @RegisterSystem(RegisterMode.CLIENT)
-public class DistrictOverlaySystem extends BaseComponentSystem {
+public class MinimapOverlaySystem extends BaseComponentSystem {
 
 
     @In
@@ -54,7 +55,7 @@ public class DistrictOverlaySystem extends BaseComponentSystem {
     @In
     private NetworkSystem networkSystem;
 
-    private Logger logger = LoggerFactory.getLogger(DistrictOverlaySystem.class);
+    private Logger logger = LoggerFactory.getLogger(MinimapOverlaySystem.class);
 
     private EntityRef clientEntity;
 
@@ -69,8 +70,9 @@ public void initialise() {
         }
         isOverlayAdded = new HashMap<>();
     }
+
     @ReceiveEvent
-    public void onAddOverlayEvent(AddDistrictOverlayEvent event, EntityRef entityRef) {
+    public void onAddDistrictOverlayEvent(AddDistrictOverlayEvent event, EntityRef entityRef) {
         if (networkSystem.getMode() == NetworkMode.NONE && !isOverlaySinglePlayerAdded) {
             Iterator<EntityRef> entityRefs =  entityManager.getEntitiesWith(SettlementsCacheComponent.class).iterator();
             if (entityRefs.hasNext()) {
@@ -105,6 +107,34 @@ public void onAddOverlayEvent(AddDistrictOverlayEvent event, EntityRef entityRef
         }
     }
 
+    @ReceiveEvent
+    public void onAddCentreOverlayEvent(AddCentreOverlayEvent event, EntityRef entityRef) {
+        if (networkSystem.getMode() == NetworkMode.NONE) {
+            Iterator<EntityRef> entities = entityManager.getEntitiesWith(SettlementsCacheComponent.class).iterator();
+            if (entities.hasNext()) {
+                minimapSystem.addOverlay(new CentreOverlay(entities.next()));
+            }
+        }
+
+        if (networkSystem.getMode() == NetworkMode.CLIENT) {
+            if (clientEntity.getComponent(ClientComponent.class).character.getId() == entityRef.getId() && !isOverlayAdded.getOrDefault(entityRef, false)) {
+                Iterator<EntityRef> entities = entityManager.getEntitiesWith(SettlementsCacheComponent.class).iterator();
+                if (entities.hasNext()) {
+                    minimapSystem.addOverlay(new CentreOverlay(entities.next()));
+                }
+            }
+        }
+
+        if (networkSystem.getMode() == NetworkMode.DEDICATED_SERVER && !isOverlayAdded.getOrDefault(entityRef, false)) {
+            if (localPlayer.getCharacterEntity() == entityRef) {
+                Iterator<EntityRef> entities = entityManager.getEntitiesWith(SettlementsCacheComponent.class).iterator();
+                if (entities.hasNext()) {
+                    minimapSystem.addOverlay(new CentreOverlay(entities.next()));
+                }
+            }
+        }
+    }
+
     @ReceiveEvent
     public void onRemoveDistrictOverlayEvent(RemoveDistrictOverlayEvent event, EntityRef entityRef) {
         if (networkSystem.getMode() == NetworkMode.CLIENT) {

src/main/java/org/terasology/dynamicCities/minimap/events/AddCentreOverlayEvent.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2019 MovingBlocks
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.terasology.dynamicCities.minimap.events;
+
+import org.terasology.entitySystem.event.Event;
+import org.terasology.network.BroadcastEvent;
+
+@BroadcastEvent
+public class AddCentreOverlayEvent implements Event {
+    public AddCentreOverlayEvent() {
+
+    }
+}

src/main/java/org/terasology/dynamicCities/settlements/SettlementCachingSystem.java

@@ -18,6 +18,7 @@
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.terasology.dynamicCities.minimap.events.AddCentreOverlayEvent;
 import org.terasology.dynamicCities.minimap.events.AddDistrictOverlayEvent;
 import org.terasology.dynamicCities.minimap.events.RemoveDistrictOverlayEvent;
 import org.terasology.dynamicCities.playerTracking.OnEnterSettlementEvent;
@@ -93,6 +94,7 @@ public void registerSettlement(SettlementRegisterEvent event, EntityRef settleme
     @ReceiveEvent
     public void addOverlayToClient(OnEnterSettlementEvent event, EntityRef player) {
         player.send(new AddDistrictOverlayEvent());
+        player.send(new AddCentreOverlayEvent());
     }
 
     @ReceiveEvent