From 044b47cfd59d8f9d30d9d29db618b0f1cee0962f Mon Sep 17 00:00:00 2001
From: Anuken <arnukren@gmail.com>
Date: Thu, 3 Jul 2025 23:29:05 -0400
Subject: [PATCH] Unit avoidance for wave pathfinder (mostly broken)

---
 core/src/mindustry/ai/Pathfinder.java         | 52 ++++++++++++++++++-
 .../entities/units/AIController.java          |  2 +-
 gradle.properties                             |  2 +-
 3 files changed, 52 insertions(+), 4 deletions(-)

diff --git a/core/src/mindustry/ai/Pathfinder.java b/core/src/mindustry/ai/Pathfinder.java
index 2c950e8636..70886f5f4f 100644
--- a/core/src/mindustry/ai/Pathfinder.java
+++ b/core/src/mindustry/ai/Pathfinder.java
@@ -107,6 +107,8 @@ public class Pathfinder implements Runnable{
 
     boolean needsRefresh;
 
+    int[][] avoidance;
+
     public Pathfinder(){
         clearCache();
 
@@ -121,6 +123,7 @@ public class Pathfinder implements Runnable{
             mainList = new Seq<>();
             clearCache();
 
+            avoidance = new int[4][tiles.length];
 
             for(int i = 0; i < tiles.length; i++){
                 Tile tile = world.tiles.geti(i);
@@ -143,6 +146,38 @@ public class Pathfinder implements Runnable{
             start();
         });
 
+        //TODO: the before/after game update avoidance code is very slow, but it works as a concept. future versions can do the clearing/area definitions in another thread
+
+        Events.run(Trigger.beforeGameUpdate, () -> {
+            for(var unit : Groups.unit){
+                if(!unit.isFlying()){
+                    int layer = unit.collisionLayer();
+                    if(layer < avoidance.length){
+                        float scaling = 2f;
+                        int r = Math.max(1, Mathf.ceil(unit.hitSize * 0.6f / tilesize * scaling));
+                        var arr = avoidance[layer];
+
+                        float rad2 = (unit.hitSize * unitCollisionRadiusScale / tilesize * scaling) * (unit.hitSize * unitCollisionRadiusScale / tilesize * scaling);
+
+                        for(int dx = -r; dx <= r; dx++){
+                            for(int dy = -r; dy <= r; dy++){
+                                int x = dx + unit.tileX(), y = dy + unit.tileY();
+                                if(x >= 0 && y >= 0 && x < wwidth && y < wheight && (dx*dx + dy*dy) <= rad2){
+                                    arr[x + y * wwidth] = Math.max(arr[x + y * wwidth], unit.id);
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        });
+
+        Events.run(Trigger.afterGameUpdate, () -> {
+            for(var arr : avoidance){
+                Arrays.fill(arr, 0);
+            }
+        });
+
         Events.on(ResetEvent.class, event -> stop());
 
         Events.on(TileChangeEvent.class, event -> {
@@ -359,6 +394,11 @@ public class Pathfinder implements Runnable{
 
     /** Gets next tile to travel to. Main thread only. */
     public @Nullable Tile getTargetTile(Tile tile, Flowfield path, boolean diagonals){
+        return getTargetTile(tile, path, diagonals, -1, 0);
+    }
+
+    /** Gets next tile to travel to. Main thread only. */
+    public @Nullable Tile getTargetTile(Tile tile, Flowfield path, boolean diagonals, int collisionLayer, int unitId){
         if(tile == null) return null;
 
         //uninitialized flowfields are not applicable
@@ -390,6 +430,7 @@ public class Pathfinder implements Runnable{
         int value = values[apos];
 
         var points = diagonals ? Geometry.d8 : Geometry.d4;
+        int[] avoid = collisionLayer == -1 ? null : avoidance[collisionLayer];
 
         Tile current = null;
         int tl = 0;
@@ -400,11 +441,13 @@ public class Pathfinder implements Runnable{
             if(other == null) continue;
 
             int packed = dx/res + dy/res * ww;
+            int avoidance = avoid == null || unitId == 0 ? 0 : avoid[packed] > unitId ? 1 : 0;
+            int cost = values[packed] + avoidance;
 
-            if(values[packed] < value && (current == null || values[packed] < tl) && path.passable(packed) &&
+            if(cost < value && avoidance == 0 && (current == null || cost < tl) && path.passable(packed) &&
             !(point.x != 0 && point.y != 0 && (!path.passable(((tile.x + point.x)/res + tile.y/res*ww)) || !path.passable((tile.x/res + (tile.y + point.y)/res*ww))))){ //diagonal corner trap
                 current = other;
-                tl = values[packed];
+                tl = cost;
             }
         }
 
@@ -655,6 +698,11 @@ public class Pathfinder implements Runnable{
             return pathfinder.getTargetTile(from, this);
         }
 
+        /** @return the next tile to travel to for this flowfield. Main thread only. */
+        public @Nullable Tile getNextTile(Tile from, int collisionlayer, int unitId){
+            return pathfinder.getTargetTile(from, this, true, collisionlayer, unitId);
+        }
+
         public boolean hasCompleteWeights(){
             return hasComplete && completeWeights != null;
         }
diff --git a/core/src/mindustry/entities/units/AIController.java b/core/src/mindustry/entities/units/AIController.java
index 666522f54d..f474fa1bea 100644
--- a/core/src/mindustry/entities/units/AIController.java
+++ b/core/src/mindustry/entities/units/AIController.java
@@ -136,7 +136,7 @@ public class AIController implements UnitController{
 
         Tile tile = unit.tileOn();
         if(tile == null) return;
-        Tile targetTile = pathfinder.getField(unit.team, costType, pathTarget).getNextTile(tile);
+        Tile targetTile = pathfinder.getField(unit.team, costType, pathTarget).getNextTile(tile, unit.collisionLayer(), unit.id);
 
         if((tile == targetTile && stopAtTargetTile) || !unit.canPass(targetTile.x, targetTile.y)) return;
 
diff --git a/gradle.properties b/gradle.properties
index a8e0be2bf0..7cd0af7dd7 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -26,4 +26,4 @@ org.gradle.caching=true
 org.gradle.internal.http.socketTimeout=100000
 org.gradle.internal.http.connectionTimeout=100000
 android.enableR8.fullMode=false
-archash=9b55a5d628
+archash=60e47d0f1b