Add pipe coloring (#4261)

Content.Client/Atmos/Visualizers/VentPumpVisualizer.cs

@@ -0,0 +1,47 @@
+using Content.Shared.Atmos.Visuals;
+using JetBrains.Annotations;
+using Robust.Client.GameObjects;
+
+namespace Content.Client.Atmos.Visualizers
+{
+    [UsedImplicitly]
+    public class VentPumpVisualizer : AppearanceVisualizer
+    {
+        private string _offState = "vent_off";
+        private string _inState = "vent_in";
+        private string _outState = "vent_out";
+        private string _weldedState = "vent_welded";
+
+        public override void OnChangeData(AppearanceComponent component)
+        {
+            base.OnChangeData(component);
+
+            if (!component.Owner.TryGetComponent(out ISpriteComponent? sprite))
+                return;
+
+            if (!component.TryGetData(VentPumpVisuals.State, out VentPumpState state))
+                return;
+
+            switch (state)
+            {
+                case VentPumpState.Off:
+                    sprite.LayerSetState(VentVisualLayers.Vent, _offState);
+                    break;
+                case VentPumpState.In:
+                    sprite.LayerSetState(VentVisualLayers.Vent, _inState);
+                    break;
+                case VentPumpState.Out:
+                    sprite.LayerSetState(VentVisualLayers.Vent, _outState);
+                    break;
+                case VentPumpState.Welded:
+                    sprite.LayerSetState(VentVisualLayers.Vent, _weldedState);
+                    break;
+            }
+        }
+    }
+
+    public enum VentVisualLayers
+    {
+        Vent,
+    }
+}