From e16622afccaa34a5e0245ee2563ede9d4fb72aea Mon Sep 17 00:00:00 2001
From: Anuken <arnukren@gmail.com>
Date: Sun, 14 Feb 2021 20:44:40 -0500
Subject: [PATCH] Automatic retreat AI for builders/repair units

---
 core/src/mindustry/ai/types/BuilderAI.java    | 22 ++++++++++++++++-
 core/src/mindustry/ai/types/RepairAI.java     | 24 +++++++++++++++++++
 .../entities/units/AIController.java          |  2 +-
 3 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/core/src/mindustry/ai/types/BuilderAI.java b/core/src/mindustry/ai/types/BuilderAI.java
index ce8b5ae92d..8106e6731a 100644
--- a/core/src/mindustry/ai/types/BuilderAI.java
+++ b/core/src/mindustry/ai/types/BuilderAI.java
@@ -13,9 +13,12 @@ import mindustry.world.blocks.ConstructBlock.*;
 import static mindustry.Vars.*;
 
 public class BuilderAI extends AIController{
-    float buildRadius = 1500;
+    public static float buildRadius = 1500, retreatDst = 110f, fleeRange = 370f, retreatDelay = Time.toSeconds * 2f;
+
     boolean found = false;
     @Nullable Unit following;
+    @Nullable Teamc enemy;
+    float retreatTimer;
 
     @Override
     public void updateMovement(){
@@ -27,6 +30,7 @@ public class BuilderAI extends AIController{
         unit.updateBuilding = true;
 
         if(following != null){
+            retreatTimer = 0f;
             //try to follow and mimic someone
 
             //validate follower
@@ -39,9 +43,25 @@ public class BuilderAI extends AIController{
             //set to follower's first build plan, whatever that is
             unit.plans.clear();
             unit.plans.addFirst(following.buildPlan());
+        }else if(unit.buildPlan() == null){
+            //not following anyone or building
+            if(timer.get(timerTarget4, 40)){
+                enemy = target(unit.x, unit.y, fleeRange, true, true);
+            }
+
+            //fly away from enemy when not doing anything, but only after a delay
+            if((retreatTimer += Time.delta) >= retreatDelay){
+                if(enemy != null){
+                    var core = unit.closestCore();
+                    if(!unit.within(core, retreatDst)){
+                        moveTo(core, retreatDst);
+                    }
+                }
+            }
         }
 
         if(unit.buildPlan() != null){
+            retreatTimer = 0f;
             //approach request if building
             BuildPlan req = unit.buildPlan();
 
diff --git a/core/src/mindustry/ai/types/RepairAI.java b/core/src/mindustry/ai/types/RepairAI.java
index db20cc7d60..24b6ac424b 100644
--- a/core/src/mindustry/ai/types/RepairAI.java
+++ b/core/src/mindustry/ai/types/RepairAI.java
@@ -1,11 +1,16 @@
 package mindustry.ai.types;
 
+import arc.util.*;
 import mindustry.entities.*;
 import mindustry.entities.units.*;
 import mindustry.gen.*;
 import mindustry.world.blocks.ConstructBlock.*;
 
 public class RepairAI extends AIController{
+    public static float retreatDst = 160f, fleeRange = 310f, retreatDelay = Time.toSeconds * 3f;
+
+    @Nullable Teamc avoid;
+    float retreatTimer;
 
     @Override
     protected void updateMovement(){
@@ -29,6 +34,25 @@ public class RepairAI extends AIController{
 
             unit.lookAt(target);
         }
+
+        //not repairing
+        if(!(target instanceof Building)){
+            if(timer.get(timerTarget4, 40)){
+                avoid = target(unit.x, unit.y, fleeRange, true, true);
+            }
+
+            if((retreatTimer += Time.delta) >= retreatDelay){
+                //fly away from enemy when not doing anything
+                if(avoid != null){
+                    var core = unit.closestCore();
+                    if(!unit.within(core, retreatDst)){
+                        moveTo(core, retreatDst);
+                    }
+                }
+            }
+        }else{
+            retreatTimer = 0f;
+        }
     }
 
     @Override
diff --git a/core/src/mindustry/entities/units/AIController.java b/core/src/mindustry/entities/units/AIController.java
index b42c5efdb7..71bde595ce 100644
--- a/core/src/mindustry/entities/units/AIController.java
+++ b/core/src/mindustry/entities/units/AIController.java
@@ -15,7 +15,7 @@ import static mindustry.Vars.*;
 
 public class AIController implements UnitController{
     protected static final Vec2 vec = new Vec2();
-    protected static final int timerTarget = 0, timerTarget2 = 1, timerTarget3 = 2;
+    protected static final int timerTarget = 0, timerTarget2 = 1, timerTarget3 = 2, timerTarget4 = 2;
 
     protected Unit unit;
     protected Interval timer = new Interval(4);