Started work on the keyframe engine to tie everything together!

src/Artemis.Core/Models/Profile/LayerProperties/BaseLayerProperty.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using Artemis.Core.Exceptions;
+using Artemis.Core.Models.Profile.KeyframeEngines;
 
 namespace Artemis.Core.Models.Profile.LayerProperties
 {
@@ -67,12 +68,16 @@ namespace Artemis.Core.Models.Profile.LayerProperties
         /// </summary>
         public Type Type { get; set; }
 
-        protected List<BaseKeyframe> BaseKeyframes { get; set; }
         /// <summary>
-        ///     A list of keyframes defining different values of the property in time, this list contains the untyped <see cref="BaseKeyframe"/>.
+        ///     A list of keyframes defining different values of the property in time, this list contains the untyped
+        ///     <see cref="BaseKeyframe" />.
         /// </summary>
         public IReadOnlyCollection<BaseKeyframe> UntypedKeyframes => BaseKeyframes.AsReadOnly();
 
+        public KeyframeEngine KeyframeEngine { get; set; }
+
+        protected List<BaseKeyframe> BaseKeyframes { get; set; }
+
         protected object BaseValue
         {
             get => _baseValue;
@@ -80,11 +85,14 @@ namespace Artemis.Core.Models.Profile.LayerProperties
             {
                 if (value != null && value.GetType() != Type)
                     throw new ArtemisCoreException($"Cannot set value of type {value.GetType()} on property {this}, expected type is {Type}.");
-                _baseValue = value;
+                if (!Equals(_baseValue, value))
+                {
+                    _baseValue = value;
+                    OnValueChanged();
+                }
             }
         }
 
-
         public void ApplyToEntity()
         {
             // Big o' TODO
@@ -94,5 +102,16 @@ namespace Artemis.Core.Models.Profile.LayerProperties
         {
             return $"{nameof(Id)}: {Id}, {nameof(Name)}: {Name}, {nameof(Description)}: {Description}";
         }
+
+        #region Events
+
+        public event EventHandler<EventArgs> ValueChanged;
+
+        protected virtual void OnValueChanged()
+        {
+            ValueChanged?.Invoke(this, EventArgs.Empty);
+        }
+
+        #endregion
     }
 }

src/Artemis.Core/Models/Profile/LayerProperties/LayerProperty.cs

@@ -9,14 +9,18 @@ namespace Artemis.Core.Models.Profile.LayerProperties
         {
         }
 
+        /// <summary>
+        ///     The value of the property without any keyframes applied
+        /// </summary>
         public T Value
         {
-            get => (T) BaseValue;
+            get => BaseValue != null ? (T) BaseValue : default;
             set => BaseValue = value;
         }
 
         /// <summary>
-        ///     A list of keyframes defining different values of the property in time, this list contains the strongly typed <see cref="Keyframe{T}"/>
+        ///     A list of keyframes defining different values of the property in time, this list contains the strongly typed
+        ///     <see cref="Keyframe{T}" />
         /// </summary>
         public ReadOnlyCollection<Keyframe<T>> Keyframes => BaseKeyframes.Cast<Keyframe<T>>().ToList().AsReadOnly();
 
@@ -45,5 +49,17 @@ namespace Artemis.Core.Models.Profile.LayerProperties
         {
             BaseKeyframes.Clear();
         }
+
+        /// <summary>
+        /// Gets the current value using the keyframes
+        /// </summary>
+        /// <returns></returns>
+        public T GetCurrentValue()
+        {
+            if (KeyframeEngine == null)
+                return Value;
+
+            return (T) KeyframeEngine.GetCurrentValue();
+        }
     }
 }