Use modifier frequency field (#1025)

source/MonoGame.Extended/Particles/Modifiers/AgeModifier.cs

@@ -32,17 +32,17 @@ public class AgeModifier : Modifier
     /// Updates all particles by applying each interpolator in the collection to each particle.
     /// </summary>
     /// <inheritdoc/>
-    public override unsafe void Update(float elapsedSeconds, ParticleIterator iterator)
+    protected internal override unsafe void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount)
     {
         if (!Enabled) { return; }
 
-        while (iterator.HasNext)
+        for (int i = 0; i < particleCount && iterator.HasNext; i++)
         {
             Particle* particle = iterator.Next();
 
-            for (int i = 0; i < Interpolators.Count; i++)
+            for (int j = 0; j < Interpolators.Count; j++)
             {
-                Interpolators[i].Update(particle->Age, particle);
+                Interpolators[j].Update(particle->Age, particle);
             }
         }
     }

source/MonoGame.Extended/Particles/Modifiers/Containers/CircleContainerModifier.cs

@@ -64,13 +64,13 @@ public class CircleContainerModifier : Modifier
     /// Updates all particles by constraining them to the circular boundary.
     /// </summary>
     /// <inheritdoc/>
-    public override unsafe void Update(float elapsedSeconds, ParticleIterator iterator)
+    protected internal override unsafe void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount)
     {
         if (!Enabled) { return; }
 
         float radiusSq = Radius * Radius;
 
-        while (iterator.HasNext)
+        for (int i = 0; i < particleCount && iterator.HasNext; i++)
         {
             Particle* particle = iterator.Next();
 

source/MonoGame.Extended/Particles/Modifiers/Containers/RectangleContainerModifier.cs

@@ -51,11 +51,11 @@ public sealed class RectangleContainerModifier : Modifier
     /// Updates all particles by constraining them to the rectangular boundary.
     /// </summary>
     /// <inheritdoc/>
-    public override unsafe void Update(float elapsedSeconds, ParticleIterator iterator)
+    protected internal override unsafe void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount)
     {
         if (!Enabled) { return; }
 
-        while (iterator.HasNext)
+        for (int i = 0; i < particleCount && iterator.HasNext; i++)
         {
             Particle* particle = iterator.Next();
 

source/MonoGame.Extended/Particles/Modifiers/Containers/RectangleLoopContainerModifier.cs

@@ -30,11 +30,11 @@ public class RectangleLoopContainerModifier : Modifier
     /// Updates all particles by wrapping them around to the opposite side when they cross the rectangular boundary.
     /// </summary>
     /// <inheritdoc/>
-    public override unsafe void Update(float elapsedSeconds, ParticleIterator iterator)
+    protected internal override unsafe void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount)
     {
         if (!Enabled) { return; }
 
-        while (iterator.HasNext)
+        for (int i = 0; i < particleCount && iterator.HasNext; i++)
         {
             Particle* particle = iterator.Next();
 

source/MonoGame.Extended/Particles/Modifiers/DragModifier.cs

@@ -49,11 +49,11 @@ public class DragModifier : Modifier
     /// Updates all particles by applying drag forces based on their velocity.
     /// </summary>
     /// <inheritdoc/>
-    public override unsafe void Update(float elapsedSeconds, ParticleIterator iterator)
+    protected internal override unsafe void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount)
     {
         if (!Enabled) { return; }
 
-        while (iterator.HasNext)
+        for (int i = 0; i < particleCount && iterator.HasNext; i++)
         {
             Particle* particle = iterator.Next();
 

source/MonoGame.Extended/Particles/Modifiers/LinearGravityModifier.cs

@@ -41,13 +41,13 @@ public class LinearGravityModifier : Modifier
     /// Updates all particles by applying a linear gravitational force.
     /// </summary>
     /// <inheritdoc/>
-    public override unsafe void Update(float elapsedSeconds, ParticleIterator iterator)
+    protected internal override unsafe void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount)
     {
         if (!Enabled) { return; }
 
         Vector2 vector = Direction * (Strength * elapsedSeconds);
 
-        while (iterator.HasNext)
+        for (int i = 0; i < particleCount && iterator.HasNext; i++)
         {
             Particle* particle = iterator.Next();
 

source/MonoGame.Extended/Particles/Modifiers/Modifier.cs

@@ -2,6 +2,8 @@
 // Licensed under the MIT license.
 // See LICENSE file in the project root for full license information.
 
+using System;
+
 namespace MonoGame.Extended.Particles.Modifiers;
 
 /// <summary>
@@ -17,6 +19,10 @@ public abstract class Modifier
 {
     private const float DEFAULT_MODIFIER_FREQUENCY = 60.0f;
 
+    private float _frequency;
+    private float _cycleTime;
+    private int _particlesUpdatedThisCycle;
+
     /// <summary>
     /// Gets or sets the display name of this modifier.
     /// </summary>
@@ -40,7 +46,18 @@ public abstract class Modifier
     /// cost of performance. Lower values reduce CPU usage but may make particle changes appear
     /// less fluid.
     /// </remarks>
-    public float Frequency;
+    public float Frequency
+    {
+        get => _frequency;
+        set
+        {
+            if (value <= 0.0f)
+                throw new ArgumentOutOfRangeException(nameof(value), "Frequency must be greater than zero.");
+
+            _frequency = value;
+            _cycleTime = 1f / _frequency;
+        }
+    }
 
     /// <summary>
     /// Indicates whether this modifier is enabled.
@@ -65,10 +82,32 @@ public abstract class Modifier
         Enabled = true;
     }
 
+    internal void InternalUpdate(float elapsedSeconds, ParticleIterator iterator)
+    {
+        if (!Enabled || iterator.Total == 0)
+            return;
+
+        var particlesRemaining = iterator.Total - _particlesUpdatedThisCycle;
+        var particlesToUpdate = Math.Min(particlesRemaining, (int)Math.Ceiling((elapsedSeconds / _cycleTime) * iterator.Total));
+
+        if (particlesToUpdate > 0)
+        {
+            // Create a new iterator starting from the offset position
+            var offsetIterator = iterator.Reset(_particlesUpdatedThisCycle);
+
+            Update(_cycleTime, offsetIterator, particlesToUpdate);
+
+            _particlesUpdatedThisCycle += particlesToUpdate;
+        }
+
+        if (_particlesUpdatedThisCycle >= iterator.Total)
+            _particlesUpdatedThisCycle = 0;
+    }
+
     /// <summary>
     /// Updates the properties of particles according to this modifier's specific behavior.
     /// </summary>
     /// <param name="elapsedSeconds">The elapsed time, in seconds, since the last update.</param>
     /// <param name="iterator">The iterator used to iterate the particles ot update.</param>
-    public abstract void Update(float elapsedSeconds, ParticleIterator iterator);
+    protected internal abstract void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount);
 }

source/MonoGame.Extended/Particles/Modifiers/ModifierExecutionStrategy.cs

@@ -59,7 +59,7 @@ public abstract class ModifierExecutionStrategy
         {
             for (int i = 0; i < modifiers.Count; i++)
             {
-                modifiers[i].Update(elapsedSeconds, iterator.Reset());
+                modifiers[i].InternalUpdate(elapsedSeconds, iterator);
             }
         }
 
@@ -80,7 +80,7 @@ public abstract class ModifierExecutionStrategy
     {
         internal override unsafe void ExecuteModifiers(List<Modifier> modifiers, float elapsedSeconds, ParticleIterator iterator)
         {
-            TPL.ForEach(modifiers, modifier => modifier.Update(elapsedSeconds, iterator.Reset()));
+            TPL.ForEach(modifiers, modifier => modifier.InternalUpdate(elapsedSeconds, iterator));
         }
 
         public override string ToString()

source/MonoGame.Extended/Particles/Modifiers/OpacityFastFadeModifier.cs

@@ -32,11 +32,11 @@ public sealed class OpacityFastFadeModifier : Modifier
     /// Updates all particles by setting their opacity based on their age.
     /// </summary>
     /// <inheritdoc/>
-    public override unsafe void Update(float elapsedSeconds, ParticleIterator iterator)
+    protected internal override unsafe void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount)
     {
         if (!Enabled) { return; }
 
-        while (iterator.HasNext)
+        for (int i = 0; i < particleCount && iterator.HasNext; i++)
         {
             Particle* particle = iterator.Next();
 

source/MonoGame.Extended/Particles/Modifiers/RotationModifier.cs

@@ -32,13 +32,13 @@ public class RotationModifier : Modifier
     /// Updates all particles by applying rotation based on the elapsed time.
     /// </summary>
     /// <inheritdoc/>
-    public override unsafe void Update(float elapsedSeconds, ParticleIterator iterator)
+    protected internal override unsafe void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount)
     {
         if (!Enabled) { return; }
 
         float rotationRateDelta = RotationRate * elapsedSeconds;
 
-        while (iterator.HasNext)
+        for (int i = 0; i < particleCount && iterator.HasNext; i++)
         {
             Particle* particle = iterator.Next();
 

source/MonoGame.Extended/Particles/Modifiers/VelocityColorModifier.cs

@@ -58,13 +58,13 @@ public class VelocityColorModifier : Modifier
     /// Updates all particles by changing their colors based on their current velocity.
     /// </summary>
     /// <inheritdoc/>
-    public override unsafe void Update(float elapsedSeconds, ParticleIterator iterator)
+    protected internal override unsafe void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount)
     {
         if (!Enabled) { return; }
 
         float velocityThreshold2 = VelocityThreshold * VelocityThreshold;
 
-        while (iterator.HasNext)
+        for (int i = 0; i < particleCount && iterator.HasNext; i++)
         {
             Particle* particle = iterator.Next();
 

source/MonoGame.Extended/Particles/Modifiers/VelocityModifier.cs

@@ -38,13 +38,13 @@ public class VelocityModifier : Modifier
     /// Updates all particles by applying interpolators with an amount based on each particle's velocity.
     /// </summary>
     /// <inheritdoc />
-    public override unsafe void Update(float elapsedSeconds, ParticleIterator iterator)
+    protected internal override unsafe void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount)
     {
         if (!Enabled) { return; }
 
         float velocityThreshold2 = VelocityThreshold * VelocityThreshold;
 
-        while (iterator.HasNext)
+        for (int i = 0; i < particleCount && iterator.HasNext; i++)
         {
             Particle* particle = iterator.Next();
 
@@ -53,9 +53,9 @@ public class VelocityModifier : Modifier
 
             if (velocitySquared >= velocityThreshold2)
             {
-                for (int i = 0; i < Interpolators.Count; i++)
+                for (int j = 0; j < Interpolators.Count; j++)
                 {
-                    Interpolator interpolator = Interpolators[i];
+                    Interpolator interpolator = Interpolators[j];
                     interpolator.Update(1, particle);
                 }
             }
@@ -63,9 +63,9 @@ public class VelocityModifier : Modifier
             {
                 float t = (float)Math.Sqrt(velocitySquared) / VelocityThreshold;
 
-                for (int i = 0; i < Interpolators.Count; i++)
+                for (int j = 0; j < Interpolators.Count; j++)
                 {
-                    Interpolator interpolator = Interpolators[i];
+                    Interpolator interpolator = Interpolators[j];
                     interpolator.Update(t, particle);
                 }
             }

source/MonoGame.Extended/Particles/Modifiers/VortexModifier.cs

@@ -52,11 +52,11 @@ public unsafe class VortexModifier : Modifier
     /// Updates all particles by applying a gravitational force towards the vortex center.
     /// </summary>
     /// <inheritdoc/>
-    public override unsafe void Update(float elapsedSeconds, ParticleIterator iterator)
+    protected internal override unsafe void Update(float elapsedSeconds, ParticleIterator iterator, int particleCount)
     {
         if (!Enabled) { return; }
 
-        while (iterator.HasNext)
+        for (int i = 0; i < particleCount && iterator.HasNext; i++)
         {
             Particle* particle = iterator.Next();