CompositionAnimation fixes

src/Avalonia.Base/Rendering/Composition/Animations/AnimationInstanceBase.cs

@@ -30,7 +30,9 @@ protected void Initialize(CompositionProperty property, HashSet<(string name, st
             _trackedObjects = new ();
             foreach (var t in trackedObjects)
             {
-                var obj = Parameters.GetObjectParameter(t.name);
+                var obj = (t.name == ExpressionKeywords.Target) 
+                    ? TargetObject 
+                    : Parameters.GetObjectParameter(t.name);
                 if (obj is ServerObject tracked)
                 {
                     var off = tracked.GetCompositionProperty(t.member);

src/Avalonia.Base/Rendering/Composition/Expressions/DelegateExpressionFfi.cs

@@ -62,12 +62,10 @@ bool CallWithCast(List<FfiRecord> countGroup, IReadOnlyList<ExpressionVariant> a
                     var arg = arguments[c].Type;
                     if (parameter != arg)
                     {
-                        var canCast = (parameter == VariantType.Double && arg == VariantType.Scalar)
-                                      || (parameter == VariantType.Vector3D && arg == VariantType.Vector3)
+                        var canCast =  (parameter == VariantType.Vector3D && arg == VariantType.Vector3)
                                       || (parameter == VariantType.Vector && arg == VariantType.Vector2)
                                       || (anyCast && (
-                                          (arg == VariantType.Double && parameter == VariantType.Scalar)
-                                          || (arg == VariantType.Vector3D && parameter == VariantType.Vector3)
+                                          (arg == VariantType.Vector3D && parameter == VariantType.Vector3)
                                           || (arg == VariantType.Vector && parameter == VariantType.Vector2)
                                       ));
                         if (!canCast)
@@ -112,7 +110,7 @@ void Add(string name, Func<IReadOnlyList<ExpressionVariant>, ExpressionVariant>
         static readonly Dictionary<Type, VariantType> TypeMap = new Dictionary<Type, VariantType>
         {
             [typeof(bool)] = VariantType.Boolean,
-            [typeof(float)] = VariantType.Scalar,
+            [typeof(float)] = VariantType.Double,
             [typeof(double)] = VariantType.Double,
             [typeof(Vector2)] = VariantType.Vector2,
             [typeof(Vector)] = VariantType.Vector,

src/Avalonia.Base/Rendering/Composition/Expressions/Expression.cs

@@ -104,6 +104,17 @@ internal enum ExpressionKeyword
         False
     }
 
+    internal class ExpressionKeywords
+    {
+        public const string StartingValue = "this.startingvalue";
+        public const string CurrentValue = "this.currentvalue";
+        public const string FinalValue = "this.finalvalue";
+        public const string Pi = "pi";
+        public const string True = "true";
+        public const string False = "false";
+        public const string Target = "this.target";
+    }
+
     internal class ConditionalExpression : Expression
     {
         public Expression Condition { get; }
@@ -202,6 +213,10 @@ public override void CollectReferences(HashSet<(string parameter, string propert
             Target.CollectReferences(references);
             if (Target is ParameterExpression pe)
                 references.Add((pe.Name, Member));
+            else if (Target is KeywordExpression { Keyword : ExpressionKeyword.Target })
+            {
+                references.Add((ExpressionKeywords.Target, Member));
+            }
         }
 
         public override ExpressionVariant Evaluate(ref ExpressionEvaluationContext context)

src/Avalonia.Base/Rendering/Composition/Expressions/ExpressionParser.cs

@@ -25,19 +25,19 @@ static bool TryParseAtomic(ref TokenParser parser,
         {
             // We can parse keywords, parameter names and constants
             expr = null;
-            if (parser.TryParseKeywordLowerCase("this.startingvalue"))
+            if (parser.TryParseKeywordLowerCase(ExpressionKeywords.StartingValue))
                 expr = new KeywordExpression(ExpressionKeyword.StartingValue);
-            else if(parser.TryParseKeywordLowerCase("this.currentvalue"))
+            else if(parser.TryParseKeywordLowerCase(ExpressionKeywords.CurrentValue))
                 expr = new KeywordExpression(ExpressionKeyword.CurrentValue);
-            else if(parser.TryParseKeywordLowerCase("this.finalvalue"))
+            else if(parser.TryParseKeywordLowerCase(ExpressionKeywords.FinalValue))
                 expr = new KeywordExpression(ExpressionKeyword.FinalValue);
-            else if(parser.TryParseKeywordLowerCase("pi"))
+            else if(parser.TryParseKeywordLowerCase(ExpressionKeywords.Pi))
                 expr = new KeywordExpression(ExpressionKeyword.Pi);
-            else if(parser.TryParseKeywordLowerCase("true"))
+            else if(parser.TryParseKeywordLowerCase(ExpressionKeywords.True))
                 expr = new KeywordExpression(ExpressionKeyword.True);
-            else if(parser.TryParseKeywordLowerCase("false"))
+            else if(parser.TryParseKeywordLowerCase(ExpressionKeywords.False))
                 expr = new KeywordExpression(ExpressionKeyword.False);
-            else if (parser.TryParseKeywordLowerCase("this.target"))
+            else if (parser.TryParseKeywordLowerCase(ExpressionKeywords.Target))
                 expr = new KeywordExpression(ExpressionKeyword.Target);
 
             if (expr != null)