finalized dirt

added base for liquids

Scripts/Elements/Dirt.cs

@@ -11,10 +11,14 @@ public class Dirt : Solid {
     public override bool Update(int currentFrame) {
         if (!base.Update(currentFrame)) return false;
 
-        if (CheckBelow(X, Y)) {
-            _level.Swap(this, X, Y+1);
+        Vector2I freePos = Check(this, Vector2I.Down + Vector2I.Right);
+
+        if (freePos != Vector2I.Zero) { // diagonally right
+            _level.Swap(this, freePos);
+            return true;
         }
-        return true;
+
+        return true; // not necessarily end, subclasses could do some more things
     }
 
 }

Scripts/Elements/Element.cs

@@ -5,16 +5,15 @@ namespace FOU.Scripts.Elements;
 public class Element {
     public Color Color = Colors.Black;
 
-    public int X;
-    public int Y;
+    public Vector2I Position;
 
     protected Level _level;
 
     private int _lastUpdate = -1;
 
     public Element(int x, int y, ref Level level) {
-        X = x;
-        Y = y;
+        Position.X = x;
+        Position.Y = y;
         _level = level;
     }
 
@@ -31,15 +30,25 @@ public class Element {
     }
 
     public override string ToString() {
-        return $"{GetType()} {X}:{Y}";
+        return $"{GetType()} {Position}";
     }
 
-    protected bool CheckBelow(int x, int y) {
-        if (y+1 >= _level.SizeY) return false;
+    // OBSOLETE:
+    // protected bool CheckBelow(int sourceX, int sourceY) {
+    //     if (sourceY+1 >= _level.SizeY) return false;
+    //
+    //     if (_level.Get(sourceX, sourceY+1).GetType() == GetType())
+    //         return false;
+    //
+    //     return true;
+    // }
 
-        if (_level.Get(x, y+1).GetType() == GetType())
-            return false;
-
-        return true;
-    }
-}
+    /// <summary>
+    /// Checks from source to maxDirection (also X-mirrored) and returns a free position
+    /// </summary>
+    /// <param name="source">from where to check</param>
+    /// <param name="maxDirection">where to go to (max). X is treated as [-X..X]</param>
+    /// <returns>free position or V2.zero if nothing was found</returns>
+    protected virtual Vector2I Check(Element source, Vector2I maxDirection) {
+        return Vector2I.Zero;
+    }}

Scripts/Elements/Liquid.cs

@@ -0,0 +1,34 @@
+using Godot;
+
+namespace FOU.Scripts.Elements;
+
+public abstract class Liquid : Element {
+    protected Liquid(int x, int y, ref Level level) : base(x, y, ref level) { }
+
+    protected override Vector2I Check(Element source, Vector2I maxDirection) {
+        if (GD.Randi() % 2 != 0)
+            maxDirection.X *= -1;
+
+        Vector2I freePos = Vector2I.Zero;
+        for (int y = 0; y <= maxDirection.Y; y++) { // height
+            if (source.Position.Y + y >= _level.SizeY) return freePos; // bounds check
+
+            if (_level.Get(source.Position.X, source.Position.Y + y).GetType() == typeof(Element)) {
+                freePos = new Vector2I(source.Position.X, source.Position.Y + y);
+            }
+
+            for (int x = -maxDirection.X; x <= maxDirection.X; x++) { // width
+                if (freePos != Vector2I.Zero) break;
+
+                if (source.Position.X + x >= _level.SizeX || source.Position.X + x < 0) return freePos; // bounds check
+
+                if (_level.Get(source.Position.X + x, source.Position.Y + y).GetType() == typeof(Element)) {
+                    freePos = new Vector2I(source.Position.X + x, source.Position.Y + y);
+                    break;
+                }
+            }
+        }
+
+        return freePos;
+    }
+}

Scripts/Elements/Solid.cs

@@ -1,5 +1,36 @@
-namespace FOU.Scripts.Elements;
+using Godot;
+
+namespace FOU.Scripts.Elements;
 
 public abstract class Solid : Element {
     protected Solid(int x, int y, ref Level level) : base(x, y, ref level) { }
+
+    protected Vector2I Check(Element source, Vector2I maxDirection) {
+        if (GD.Randi() % 2 != 0)
+            maxDirection.X *= -1;
+
+        Vector2I freePos = Vector2I.Zero;
+        for (int y = maxDirection.Y; y > 0; y--) { // height
+            if (source.Position.Y + y >= _level.SizeY) return freePos; // bounds check
+
+            if (_level.Get(source.Position.X, source.Position.Y + y).GetType() == typeof(Element)) {
+                freePos = new Vector2I(source.Position.X, source.Position.Y + y);
+            } else {
+                freePos = Vector2I.Zero;
+            }
+
+            for (int x = -maxDirection.X; x <= maxDirection.X; x++) { // width
+                if (freePos != Vector2I.Zero) break;
+
+                if (source.Position.X + x >= _level.SizeX || source.Position.X + x < 0) return freePos; // bounds check
+
+                if (_level.Get(source.Position.X + x, source.Position.Y + y).GetType() == typeof(Element)) {
+                    freePos = new Vector2I(source.Position.X + x, source.Position.Y + y);
+                    break;
+                }
+            }
+        }
+
+        return freePos;
+    }
 }