Hull-specific ambient lighting: light sources increase the amount of ambient light in rooms and the light can spread to adjacent rooms through gaps. Allows making the default ambient light much darker without making shadows look too dark in fully lit subs.

Subsurface/Content/Items/Electricity/lights.xml

@@ -10,8 +10,8 @@
 
     <Sprite texture="lamp.png" sourcerect="0,0,16,32" depth="0.8"/>
 
-    <LightComponent color="1.0,1.0,1.0,1.0" range ="800.0" powerconsumption="5">
+    <LightComponent lightcolor="1.0,1.0,1.0,1.0" range ="800.0" powerconsumption="5">
-      <sprite texture="Content/Items/Electricity/lamp.png" sourcerect="33,0,31,39"/>
+      <sprite texture="Content/Items/Electricity/lamp.png" sourcerect="33,0,31,37"/>
     </LightComponent>
 
     <ConnectionPanel selectkey="Action" canbeselected = "true" msg="Rewire [Screwdriver]">
@@ -20,8 +20,25 @@
       <input name="toggle"/>
       <input name="set_state"/>      
     </ConnectionPanel>
-
   </Item>
 
+  <Item
+    name="Emergency Light"
+    category="Electrical"
+    Tags="smallitem"
+    pickdistance="150">
+
+    <Sprite texture="lamp.png" sourcerect="0,48,48,16" depth="0.8"/>
+
+    <LightComponent lightcolor="1.0,0.0,0.0,0.2" range="500.0" IsOn="true">
+      <sprite texture="Content/Items/Electricity/lamp.png" sourcerect="0,48,48,16"/>
+    </LightComponent>
+    
+    <ConnectionPanel selectkey="Action" canbeselected = "true" msg="Rewire [Screwdriver]">
+      <requireditem name="Screwdriver,Wire" type="Equipped"/>
+      <input name="toggle"/>
+      <input name="set_state"/>
+    </ConnectionPanel>
+  </Item>
 </Items>
 

Subsurface/Source/Items/Components/Door.cs

@@ -56,10 +56,15 @@ namespace Barotrauma.Items.Components
             get
             {
                 if (linkedGap != null) return linkedGap;
+
                 foreach (MapEntity e in item.linkedTo)
                 {
                     linkedGap = e as Gap;
-                    if (linkedGap != null) return linkedGap;
+                    if (linkedGap != null)
+                    {
+                        linkedGap.PassAmbientLight = window != Rectangle.Empty;
+                        return linkedGap;
+                    }
                 }
                 Rectangle rect = item.Rect;
                 if (isHorizontal)
@@ -75,6 +80,7 @@ namespace Barotrauma.Items.Components
 
                 linkedGap = new Gap(rect, Item.Submarine);
                 linkedGap.Submarine = item.Submarine;
+                linkedGap.PassAmbientLight = window != Rectangle.Empty;
                 linkedGap.Open = openState;
                 item.linkedTo.Add(linkedGap);
                 return linkedGap;

Subsurface/Source/Map/Gap.cs

@@ -30,9 +30,14 @@ namespace Barotrauma
         private float higherSurface;
         private float lowerSurface;
 
+        private Vector2 lerpedFlowForce;
+
         //if set to true, hull connections of this gap won't be updated when changes are being done to hulls
         public bool DisableHullRechecks;
         
+        //can ambient light get through the gap even if it's not open
+        public bool PassAmbientLight;
+
         public float Open
         {
             get { return open; }
@@ -48,8 +53,6 @@ namespace Barotrauma
             get { return lerpedFlowForce; }
         }
 
-        private Vector2 lerpedFlowForce;
-
         public Hull FlowTargetHull
         {
             get { return flowTargetHull; }

Subsurface/Source/Map/Hull.cs

@@ -723,7 +723,6 @@ namespace Barotrauma
             }
 
             var entities = EntityGrid.GetEntities(entityGrids, position, useWorldCoordinates);
-
             foreach (Hull hull in entities)
             {
                 if (Submarine.RectContains(useWorldCoordinates ? hull.WorldRect : hull.rect, position)) return hull;

Subsurface/Source/Map/Levels/Level.cs

@@ -181,7 +181,7 @@ namespace Barotrauma
             
             backgroundColor = generationParams.BackgroundColor;
             float avgValue = (backgroundColor.R + backgroundColor.G + backgroundColor.G) / 3;
-            GameMain.LightManager.AmbientLight = new Color(backgroundColor * (60.0f / avgValue), 1.0f);
+            GameMain.LightManager.AmbientLight = new Color(backgroundColor * (10.0f / avgValue), 1.0f);
 
             float minWidth = Submarine.MainSub == null ? 0.0f : Math.Max(Submarine.MainSub.Borders.Width, Submarine.MainSub.Borders.Height);
             minWidth = Math.Max(minWidth, 6500.0f);

Subsurface/Source/Map/Lights/LightManager.cs

@@ -8,7 +8,9 @@ namespace Barotrauma.Lights
 {
     class LightManager
     {
-        //public static Vector2 ViewPos;
+        private const float AmbientLightUpdateInterval = 0.2f;
+        private const float AmbientLightFalloff = 0.8f;
+
         private static Entity viewTarget;
 
         public static Entity ViewTarget
@@ -36,11 +38,16 @@ namespace Barotrauma.Lights
 
         private Texture2D visionCircle;
         
+        private Dictionary<Hull, Color> hullAmbientLights = new Dictionary<Hull, Color>();
+        private Dictionary<Hull, Color> smoothedHullAmbientLights = new Dictionary<Hull, Color>();
+
+        private float ambientLightUpdateTimer;
+
         public LightManager(GraphicsDevice graphics)
         {
             lights = new List<LightSource>();
 
-            AmbientLight = new Color(60, 60, 60, 255);
+            AmbientLight = new Color(20, 20, 20, 255);
 
             visionCircle = Sprite.LoadTexture("Content/Lights/visioncircle.png");
 
@@ -53,7 +60,10 @@ namespace Barotrauma.Lights
 
             losTexture = new RenderTarget2D(graphics, GameMain.GraphicsWidth, GameMain.GraphicsHeight);
 
-            if (alphaClearTexture==null)
+            hullAmbientLights = new Dictionary<Hull, Color>();
+            smoothedHullAmbientLights = new Dictionary<Hull, Color>();
+
+            if (alphaClearTexture == null)
             {
                 alphaClearTexture = TextureLoader.FromFile("Content/Lights/alphaOne.png");
             }
@@ -77,7 +87,38 @@ namespace Barotrauma.Lights
             }
         }
 
-        public void UpdateLightMap(GraphicsDevice graphics, SpriteBatch spriteBatch, Camera cam)
+        public void Update(float deltaTime)
+        {
+            if (ambientLightUpdateTimer > 0.0f)
+            {
+                ambientLightUpdateTimer -= deltaTime;
+            }
+            else
+            {
+                CalculateAmbientLights();
+
+                ambientLightUpdateTimer = AmbientLightUpdateInterval;
+            }
+
+            foreach (Hull hull in hullAmbientLights.Keys)
+            {
+                if (!smoothedHullAmbientLights.ContainsKey(hull))
+                {
+                    smoothedHullAmbientLights.Add(hull, Color.TransparentBlack);
+                }
+            }
+
+            foreach (Hull hull in smoothedHullAmbientLights.Keys.ToList())
+            {
+                Color targetColor = Color.TransparentBlack;
+
+                hullAmbientLights.TryGetValue(hull, out targetColor);
+
+                smoothedHullAmbientLights[hull] = Color.Lerp(smoothedHullAmbientLights[hull], targetColor, deltaTime);
+            }
+        }
+
+        public void UpdateLightMap(GraphicsDevice graphics, SpriteBatch spriteBatch, Camera cam, Effect blur)
         {
             if (!LightingEnabled) return;
 
@@ -94,7 +135,7 @@ namespace Barotrauma.Lights
             
             foreach (LightSource light in lights)
             {
-                if (light.Color.A < 0.01f || light.Range < 1.0f || !light.CastShadows) continue;
+                if (light.Color.A < 1 || light.Range < 1.0f || !light.CastShadows) continue;
                 if (!MathUtils.CircleIntersectsRectangle(light.WorldPosition, light.Range, viewRect)) continue;
                             
                 //clear alpha to 1
@@ -118,7 +159,6 @@ namespace Barotrauma.Lights
 
             ClearAlphaToOne(graphics, spriteBatch);
             
-
             spriteBatch.Begin(SpriteSortMode.Deferred, CustomBlendStates.MultiplyWithAlpha, null, null, null, null, cam.Transform);
 
             GameMain.ParticleManager.Draw(spriteBatch, false, Particles.ParticleBlendState.Additive);
@@ -126,7 +166,7 @@ namespace Barotrauma.Lights
 
             foreach (LightSource light in lights)
             {
-                if (light.Color.A < 0.01f || light.Range < 1.0f || light.CastShadows) continue;
+                if (light.Color.A < 1 || light.Range < 1.0f || light.CastShadows) continue;
                 //if (!MathUtils.CircleIntersectsRectangle(light.WorldPosition, light.Range, viewRect)) continue;
 
                 light.Draw(spriteBatch);
@@ -147,6 +187,27 @@ namespace Barotrauma.Lights
             }
             spriteBatch.End();
 
+
+            spriteBatch.Begin(SpriteSortMode.Deferred, BlendState.Additive, null, null, null, null, cam.Transform);
+
+            foreach (Hull hull in smoothedHullAmbientLights.Keys)
+            {
+                if (smoothedHullAmbientLights[hull].A < 0.01f) continue;
+
+                var drawRect =
+                    hull.Submarine == null ?
+                    hull.Rect :
+                    new Rectangle((int)(hull.Submarine.DrawPosition.X + hull.Rect.X), (int)(hull.Submarine.DrawPosition.Y + hull.Rect.Y), hull.Rect.Width, hull.Rect.Height);
+
+                GUI.DrawRectangle(spriteBatch,
+                    new Vector2(drawRect.X, -drawRect.Y),
+                    new Vector2(hull.Rect.Width, hull.Rect.Height),
+                    smoothedHullAmbientLights[hull] * 0.5f, true);
+            }
+
+            spriteBatch.End();
+
+
             //clear alpha, to avoid messing stuff up later
             ClearAlphaToOne(graphics, spriteBatch);
             
@@ -173,8 +234,6 @@ namespace Barotrauma.Lights
 
                 spriteBatch.Draw(visionCircle, new Vector2(ViewTarget.WorldPosition.X, -ViewTarget.WorldPosition.Y), null, Color.White, rotation, 
                     new Vector2(LightSource.LightTexture.Width*0.2f, LightSource.LightTexture.Height/2), scale, SpriteEffects.None, 0.0f);
-
-
             }
             else
             {
@@ -210,6 +269,86 @@ namespace Barotrauma.Lights
             graphics.SetRenderTarget(null);            
         }
         
+
+        private void CalculateAmbientLights()
+        {
+            hullAmbientLights.Clear();
+
+            foreach (LightSource light in lights)
+            {
+                if (light.Color.A < 1f || light.Range < 1.0f) continue;
+
+                var newAmbientLights = AmbientLightHulls(light);
+                foreach (Hull hull in newAmbientLights.Keys)
+                {
+                    if (hullAmbientLights.ContainsKey(hull))
+                    {
+                        //hull already lit by some other light source -> add the ambient lights up
+                        hullAmbientLights[hull] = new Color(
+                            hullAmbientLights[hull].R + newAmbientLights[hull].R, 
+                            hullAmbientLights[hull].G + newAmbientLights[hull].G, 
+                            hullAmbientLights[hull].B + newAmbientLights[hull].B,
+                            hullAmbientLights[hull].A + newAmbientLights[hull].A);
+                    }
+                    else
+                    {
+                        hullAmbientLights.Add(hull, newAmbientLights[hull]);
+                    }
+                }
+            }
+        }
+
+        /// <summary>
+        /// Add ambient light to the hull the lightsource is inside + all adjacent hulls connected by a gap
+        /// </summary>
+        private Dictionary<Hull, Color> AmbientLightHulls(LightSource light)
+        {
+            Dictionary<Hull, Color> hullAmbientLight = new Dictionary<Hull, Color>();
+
+            var hull = Hull.FindHull(light.WorldPosition);
+            if (hull == null) return hullAmbientLight;
+
+            return AmbientLightHulls(hull, hullAmbientLight, light.Color * (light.Range/2000.0f));
+        }
+
+        /// <summary>
+        /// A flood fill algorithm that adds ambient light to all hulls the starting hull is connected to
+        /// </summary>
+        private Dictionary<Hull, Color> AmbientLightHulls(Hull hull, Dictionary<Hull, Color> hullAmbientLight, Color currColor)
+        {
+            if (hullAmbientLight.ContainsKey(hull))
+            {
+                if (hullAmbientLight[hull].A > currColor.A)
+                    return hullAmbientLight;
+                else
+                    hullAmbientLight[hull] = currColor;
+            }
+            else
+            {
+                hullAmbientLight.Add(hull, currColor);
+            }
+
+            foreach (Gap g in hull.ConnectedGaps)
+            {
+                for (int i = 0; i < g.linkedTo.Count;i++ )
+                {
+                    if (g.linkedTo[i] is Hull)
+                    {
+                        if (g.linkedTo[i] == hull) continue;
+
+                        Color nextHullLight = currColor * AmbientLightFalloff;
+                        if (!g.PassAmbientLight) nextHullLight *= g.Open;                        
+
+                        if (nextHullLight.A < 10) continue;
+
+                        hullAmbientLight = AmbientLightHulls((Hull)g.linkedTo[i], hullAmbientLight, nextHullLight);
+                    }
+                }
+            }
+
+            return hullAmbientLight;
+        }
+
         private void ClearAlphaToOne(GraphicsDevice graphics, SpriteBatch spriteBatch)
         {
             spriteBatch.Begin(SpriteSortMode.Deferred, CustomBlendStates.WriteToAlpha);
@@ -217,7 +356,7 @@ namespace Barotrauma.Lights
             spriteBatch.End();
         }
 
-        public void DrawLightMap(SpriteBatch spriteBatch, Camera cam, Effect effect)
+        public void DrawLightMap(SpriteBatch spriteBatch, Effect effect)
         {
             if (!LightingEnabled) return;
 
@@ -227,11 +366,11 @@ namespace Barotrauma.Lights
             spriteBatch.End();
         }
 
-        public void DrawLOS(GraphicsDevice graphics, SpriteBatch spriteBatch, Camera cam, Effect effect)
+        public void DrawLOS(SpriteBatch spriteBatch, Effect effect)
         {
             if (!LosEnabled || ViewTarget == null) return;
 
-            spriteBatch.Begin(SpriteSortMode.Deferred, CustomBlendStates.Multiplicative, null, null, null);
+            spriteBatch.Begin(SpriteSortMode.Deferred, CustomBlendStates.Multiplicative, null, null, null, effect);
             spriteBatch.Draw(losTexture, Vector2.Zero, Color.White);
             spriteBatch.End();
 
@@ -264,9 +403,6 @@ namespace Barotrauma.Lights
         public static BlendState Multiplicative { get; private set; }
         public static BlendState WriteToAlpha { get; private set; }
         public static BlendState MultiplyWithAlpha { get; private set; }
-
-
-
     }
 
 }

Subsurface/Source/Map/Lights/LightSource.cs

@@ -306,20 +306,21 @@ namespace Barotrauma.Lights
                     Vector2 center = new Vector2(LightTexture.Width / 2, LightTexture.Height / 2);
                     float scale = range / (lightTexture.Width / 2.0f);
 
-                    spriteBatch.Draw(lightTexture, new Vector2(WorldPosition.X, -WorldPosition.Y), null, color, 0, center, scale, SpriteEffects.None, 1);
+                    spriteBatch.Draw(lightTexture, new Vector2(WorldPosition.X, -WorldPosition.Y), null, color * (color.A / 255.0f), 0, center, scale, SpriteEffects.None, 1);
                 }
                 else
                 {
                     overrideLightTexture.Draw(spriteBatch,
-                        new Vector2(WorldPosition.X, -WorldPosition.Y), Color, 
+                        new Vector2(WorldPosition.X, -WorldPosition.Y), color * (color.A / 255.0f),
                         overrideLightTexture.Origin, -Rotation,
-                        new Vector2(overrideLightTexture.size.X/overrideLightTexture.SourceRect.Width, overrideLightTexture.size.Y/overrideLightTexture.SourceRect.Height));
+                        new Vector2(overrideLightTexture.size.X / overrideLightTexture.SourceRect.Width, overrideLightTexture.size.Y / overrideLightTexture.SourceRect.Height));
                 }
             }
 
             if (LightSprite != null)
             {
                 LightSprite.Draw(spriteBatch, new Vector2(WorldPosition.X, -WorldPosition.Y), Color, LightSprite.Origin);
+
             } 
         }
 

Subsurface/Source/Screens/GameScreen.cs

@@ -128,6 +128,8 @@ namespace Barotrauma
             {
                 cam.TargetPos = Lights.LightManager.ViewTarget.WorldPosition;
             }
+
+            GameMain.LightManager.Update((float)deltaTime);
             cam.MoveCamera((float)deltaTime);
                 
             foreach (Submarine sub in Submarine.Loaded)
@@ -205,7 +207,7 @@ namespace Barotrauma
 
             GameMain.LightManager.ObstructVision = Character.Controlled != null && Character.Controlled.ObstructVision;
 
-            GameMain.LightManager.UpdateLightMap(graphics, spriteBatch, cam);
+            GameMain.LightManager.UpdateLightMap(graphics, spriteBatch, cam, lightBlur.Effect);
             if (Character.Controlled != null)
             {
                 GameMain.LightManager.UpdateObstructVision(graphics, spriteBatch, cam, Character.Controlled.CursorWorldPosition);
@@ -339,8 +341,7 @@ namespace Barotrauma
                         
             spriteBatch.End();
 
-
+            GameMain.LightManager.DrawLightMap(spriteBatch, lightBlur.Effect);
-            GameMain.LightManager.DrawLightMap(spriteBatch, cam, lightBlur.Effect);
 
             spriteBatch.Begin(SpriteSortMode.BackToFront,
                 BlendState.AlphaBlend, SamplerState.LinearWrap,
@@ -355,7 +356,7 @@ namespace Barotrauma
 
             if (Character.Controlled != null)
             {
-                GameMain.LightManager.DrawLOS(graphics, spriteBatch, cam, lightBlur.Effect);
+                GameMain.LightManager.DrawLOS(spriteBatch, lightBlur.Effect);
             }
 
         }