Trench height

Source/CombatExtended/CombatExtended/CollisionVertical.cs

@@ -19,11 +19,11 @@ public struct CollisionVertical
     private readonly FloatRange heightRange;
     public readonly float shotHeight;
 
-    public FloatRange HeightRange => new FloatRange(heightRange.min, heightRange.max);
+    public FloatRange HeightRange => new FloatRange(Mathf.Max(0, heightRange.min), Mathf.Max(0.1f, heightRange.max));
     public float Min => heightRange.min;
     public float Max => heightRange.max;
-    public float BottomHeight => Max * BodyRegionBottomHeight;
-    public float MiddleHeight => Max * BodyRegionMiddleHeight;
+    public float BottomHeight => Max - (heightRange.Span * (1 - BodyRegionBottomHeight));
+    public float MiddleHeight => Max - (heightRange.Span * (1 - BodyRegionMiddleHeight));
 
     public CollisionVertical(Thing thing)
     {
@@ -73,7 +73,7 @@ private static void CalculateHeightRange(Thing thing, out FloatRange heightRange
         }
         float collisionHeight = 0f;
         float shotHeightOffset = 0;
-        float heightAdjust = 0;
+        float heightAdjust = CETrenches.GetHeightAdjust(thing.Position, thing.Map);
 
         var pawn = thing as Pawn;
         if (pawn != null)
@@ -127,8 +127,10 @@ private static void CalculateHeightRange(Thing thing, out FloatRange heightRange
             }
         }
         float fillPercent2 = collisionHeight;
-        heightRange = new FloatRange(Mathf.Min(edificeHeight, edificeHeight + fillPercent2) + heightAdjust, Mathf.Max(edificeHeight, edificeHeight + fillPercent2) + heightAdjust);
-        shotHeight = heightRange.max - shotHeightOffset;
+        heightRange = new FloatRange(
+            Mathf.Min(edificeHeight, edificeHeight + fillPercent2) + heightAdjust,
+            Mathf.Max(0.1f, Mathf.Max(edificeHeight, edificeHeight + fillPercent2) + heightAdjust));
+        shotHeight = Mathf.Max(0.1f, heightRange.max - shotHeightOffset);
     }
 
     /// <summary>

Source/CombatExtended/CombatExtended/Defs/ModExtensionCover.cs

@@ -0,0 +1,7 @@
+using Verse;
+
+namespace CombatExtended;
+public class ModExtensionCover : DefModExtension
+{
+    public float heightOffset = 0f;
+}

Source/CombatExtended/Compatibility/Trenches.cs

@@ -0,0 +1,59 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using CombatExtended.CombatExtended.LoggerUtils;
+using UnityEngine;
+using Verse;
+using VFESecurity;
+
+namespace CombatExtended.Compatibility;
+[StaticConstructorOnStartup]
+public class CETrenches
+{
+    private static bool CheckTrench(IntVec3 cell, Map map, out float heightAdjust)
+    {
+        heightAdjust = 0f;
+
+        //consider swimming pawns to be partially underground
+        TerrainDef terrain = cell.GetTerrain(map);
+        if (terrain != null && terrain.IsWater)
+        {
+            heightAdjust = terrain.passability == Traversability.Impassable ? -0.5f : -0.25f;
+            return true;
+        }
+
+        //find trench building
+        List<Thing> thingList = cell.GetThingList(map);
+        foreach (Thing thing in thingList)
+        {
+            ModExtensionCover modExtProperties = thing.def.GetModExtension<ModExtensionCover>();
+            if (modExtProperties == null || modExtProperties.heightOffset == 0f)
+            {
+                continue;
+            }
+
+            heightAdjust = modExtProperties.heightOffset;
+            return true;
+        }
+
+        return false;
+    }
+
+    public static float GetHeightAdjust(IntVec3 cell, Map map)
+    {
+        if (cell == null || map == null)
+        {
+            return 0;
+        }
+
+        float heightAdjust = 0;
+
+        if (CheckTrench(cell, map, out heightAdjust))
+        {
+            return heightAdjust;
+        }
+
+        return 0f;
+    }
+}