- The emission rate of ParticleEmitters can be set as particles per second (instead of particles per frame).

- Particles that are outside the sub aren't visible inside hulls even if they overlap with the sub.
- ParticleManager takes the movement of the particles into account when determining which particles to cull. For example, a particle that will move upwards can be emitted even if it's below the camera view.

Barotrauma/BarotraumaClient/Source/Particles/Particle.cs

@@ -73,6 +73,11 @@ namespace Barotrauma.Particles
             get { return velocity; }
             set { velocity = value; }
         }
+
+        public Hull CurrentHull
+        {
+            get { return currentHull; }
+        }
         
         public void Init(ParticlePrefab prefab, Vector2 position, Vector2 speed, float rotation, Hull hullGuess = null)
         {

Barotrauma/BarotraumaClient/Source/Particles/ParticleEmitter.cs

@@ -4,7 +4,7 @@ using System.Xml.Linq;
 
 namespace Barotrauma.Particles
 {
-    class ParticleEmitterPrefab
+    class ParticleEmitter
     {        
         public readonly string Name;
 
@@ -15,10 +15,14 @@ namespace Barotrauma.Particles
         public readonly float VelocityMin, VelocityMax;
 
         public readonly float ScaleMin, ScaleMax;
+        
+        public readonly int ParticleAmount;
 
-        public readonly float ParticleAmount;
+        public readonly float ParticlesPerSecond;
+        
+        private float emitTimer;
 
-        public ParticleEmitterPrefab(XElement element)
+        public ParticleEmitter(XElement element)
         {
             Name = element.Name.ToString();
 
@@ -60,22 +64,40 @@ namespace Barotrauma.Particles
                 VelocityMax = VelocityMin;
             }
 
-            ParticleAmount = ToolBox.GetAttributeInt(element, "particleamount", 1);
+            ParticlesPerSecond = ToolBox.GetAttributeInt(element, "particlespersecond", 0);
+            ParticleAmount = ToolBox.GetAttributeInt(element, "particleamount", 0);
         }
 
-        public void Emit(Vector2 position, Hull hullGuess = null)
+        public void Emit(float deltaTime, Vector2 position, Hull hullGuess = null)
         {
+            emitTimer += deltaTime;
+            
+            if (ParticlesPerSecond > 0)
+            {
+                float emitInterval = 1.0f / ParticlesPerSecond;
+                while (emitTimer > emitInterval)
+                {
+                    Emit(position, hullGuess);
+                    emitTimer -= emitInterval;
+                }
+            }
+
             for (int i = 0; i<ParticleAmount; i++)
             {
-                float angle = Rand.Range(AngleMin, AngleMax);
-                Vector2 velocity = new Vector2((float)Math.Cos(angle), (float)Math.Sin(angle)) * Rand.Range(VelocityMin, VelocityMax);
+                Emit(position, hullGuess);
+            }
+        }
 
-                var particle = GameMain.ParticleManager.CreateParticle(particlePrefab, position, velocity, 0.0f, hullGuess);
+        private void Emit(Vector2 position, Hull hullGuess = null)
+        {
+            float angle = Rand.Range(AngleMin, AngleMax);
+            Vector2 velocity = new Vector2((float)Math.Cos(angle), (float)Math.Sin(angle)) * Rand.Range(VelocityMin, VelocityMax);
 
-                if (particle!=null)
-                {
-                    particle.Size *= Rand.Range(ScaleMin, ScaleMax);
-                }
+            var particle = GameMain.ParticleManager.CreateParticle(particlePrefab, position, velocity, 0.0f, hullGuess);
+
+            if (particle != null)
+            {
+                particle.Size *= Rand.Range(ScaleMin, ScaleMax);
             }
         }
     }

Barotrauma/BarotraumaClient/Source/Particles/ParticleManager.cs

@@ -66,19 +66,26 @@ namespace Barotrauma.Particles
 
         public Particle CreateParticle(ParticlePrefab prefab, Vector2 position, Vector2 speed, float rotation = 0.0f, Hull hullGuess = null)
         {
-            if (!Submarine.RectContains(MathUtils.ExpandRect(cam.WorldView, MaxOutOfViewDist), position)) return null;
-            //if (!cam.WorldView.Contains(position)) return null;
-
             if (particleCount >= MaxParticles) return null;
 
+            //endPos = x + vt + 1/2 * at^2
+            Vector2 particleEndPos = position + speed * prefab.LifeTime + 0.5f * prefab.VelocityChange * prefab.LifeTime * prefab.LifeTime;
+
+            Vector2 minPos = new Vector2(Math.Min(position.X, particleEndPos.X), Math.Min(position.Y, particleEndPos.Y));
+            Vector2 maxPos = new Vector2(Math.Max(position.X, particleEndPos.X), Math.Max(position.Y, particleEndPos.Y));
+
+            Rectangle expandedViewRect = MathUtils.ExpandRect(cam.WorldView, MaxOutOfViewDist);
+
+            if (minPos.X > expandedViewRect.Right || maxPos.X < expandedViewRect.X) return null;
+            if (minPos.Y > expandedViewRect.Y || maxPos.Y < expandedViewRect.Y - expandedViewRect.Height) return null;
+
             if (particles[particleCount] == null) particles[particleCount] = new Particle();
 
             particles[particleCount].Init(prefab, position, speed, rotation, hullGuess);
 
             particleCount++;
 
-            return particles[particleCount-1];
-
+            return particles[particleCount - 1];
         }
 
         public ParticlePrefab FindPrefab(string prefabName)
@@ -131,7 +138,7 @@ namespace Barotrauma.Particles
             }
         }
 
-        public void Draw(SpriteBatch spriteBatch, bool inWater, ParticleBlendState blendState)
+        public void Draw(SpriteBatch spriteBatch, bool inWater, bool? inSub, ParticleBlendState blendState)
         {
             ParticlePrefab.DrawTargetType drawTarget = inWater ? ParticlePrefab.DrawTargetType.Water : ParticlePrefab.DrawTargetType.Air;
 
@@ -139,6 +146,7 @@ namespace Barotrauma.Particles
             {
                 if (particles[i].BlendState != blendState) continue;
                 if (!particles[i].DrawTarget.HasFlag(drawTarget)) continue;
+                if (inSub.HasValue && (particles[i].CurrentHull == null) == inSub.Value) continue;
                 
                 particles[i].Draw(spriteBatch);
             }