diff --git a/sjplayer/src/sjplayer/CircleElement.d b/sjplayer/src/sjplayer/CircleElement.d
index 68a4c85..b5ce776 100644
--- a/sjplayer/src/sjplayer/CircleElement.d
+++ b/sjplayer/src/sjplayer/CircleElement.d
@@ -15,13 +15,20 @@ class CircleElement : ElementInterface {
   ///
   static struct Instance {
     /// this should be transposed
-    align(1) mat3 matrix;
+    align(1) mat3 matrix = mat3.identity;
     ///
-    align(1) float weight;
+    align(1) float weight = 1;
     ///
-    align(1) float smooth;
+    align(1) float smooth = 0;
     ///
-    align(1) vec4 color;
+    align(1) vec4 color = vec4(0, 0, 0, 0);
+  }
+
+  override void Initialize() {
+    alive        = false;
+    damage       = 0;
+    nearness_coe = 0;
+    instance     = instance.init;
   }
 
   override DamageCalculationResult CalculateDamage(vec2 p1, vec2 p2) const {
diff --git a/sjplayer/src/sjplayer/CircleElementScheduledController.d b/sjplayer/src/sjplayer/CircleElementScheduledController.d
index 55e6ed8..b298d8d 100644
--- a/sjplayer/src/sjplayer/CircleElementScheduledController.d
+++ b/sjplayer/src/sjplayer/CircleElementScheduledController.d
@@ -3,71 +3,26 @@ module sjplayer.CircleElementScheduledController;
 
 import std.typecons;
 
-import gl4d;
-
-import sjscript;
-
 import sjplayer.CircleElement,
-       sjplayer.ScheduledControllerFactory,
-       sjplayer.ScheduledControllerInterface,
-       sjplayer.VarStoreInterface,
-       sjplayer.util.MatrixFactory,
-       sjplayer.util.Parameter;
+       sjplayer.ElementScheduledController,
+       sjplayer.ScheduledControllerFactory;
 
 ///
-class CircleElementScheduledController :
-  AbstractScheduledControllerWithOperationImpl {
- public:
-  ///
-  this(
-      CircleElement        element,
-      in VarStoreInterface varstore,
-      in ParametersBlock[] operations) {
-    super(varstore, operations);
-    element_ = element;
-  }
-
- protected:
-  override void PrepareOperation(ref in ParametersBlock params) {
-    element_.alive        = true;
-    element_.damage       = 0;
-    element_.nearness_coe = 0;
-    element_.matrix       = mat3.identity.transposed;
-    element_.weight       = 1;
-    element_.smooth       = 0.01;
-    element_.color        = vec4(1, 1, 1, 1);
-
-    matrix_factory_ = matrix_factory_.init;
-
-    super.PrepareOperation(params);
-  }
-  override void ProcessOperation(float time, ref in ParametersBlock params) {
-    super.ProcessOperation(time, params);
-    element_.matrix = matrix_factory_.Create().transposed;
-  }
-  override void FinalizeOperation(ref in ParametersBlock params) {
-    element_.alive = false;
-  }
-
-  override void SetParameter(Nullable!float time, ref in Parameter param) {
-    auto vars = VarStore(this, time);
-    switch (param.name) {
-      case "damage":       return param.CalculateParameter(element_.damage,       vars);
-      case "nearness_coe": return param.CalculateParameter(element_.nearness_coe, vars);
-      case "weight":       return param.CalculateParameter(element_.weight,       vars);
-      case "smooth":       return param.CalculateParameter(element_.smooth,       vars);
-      default:
-    }
-    if (param.CalculateMatrixParameter(matrix_factory_, vars)) return;
-
-    return super.SetParameter(time, param);
-  }
-
- private:
-  CircleElement element_;
-
-  MatrixFactory matrix_factory_;
-}
+alias CircleElementScheduledController = ElementScheduledController!(
+    CircleElement,
+    [
+      "damage":       "damage",
+      "nearness_coe": "nearness_coe",
+      "weight":       "weight",
+      "smooth":       "smooth",
+      "color_r":      "color.r",
+      "color_g":      "color.g",
+      "color_b":      "color.b",
+      "color_a":      "color.a",
+    ]
+  );
+static assert(CircleElementScheduledController.AliveManagementAvailable);
+static assert(CircleElementScheduledController.MatrixModificationAvailable);
 
 ///
 alias CircleElementScheduledControllerFactory =
diff --git a/sjplayer/src/sjplayer/ElementInterface.d b/sjplayer/src/sjplayer/ElementInterface.d
index 5ed8a58..b52c6e0 100644
--- a/sjplayer/src/sjplayer/ElementInterface.d
+++ b/sjplayer/src/sjplayer/ElementInterface.d
@@ -14,6 +14,9 @@ interface ElementInterface {
     float nearness;
   }
 
+  ///
+  void Initialize();
+
   ///
   DamageCalculationResult CalculateDamage(vec2 p1, vec2 p2) const;
 }
diff --git a/sjplayer/src/sjplayer/ElementScheduledController.d b/sjplayer/src/sjplayer/ElementScheduledController.d
new file mode 100644
index 0000000..707f4af
--- /dev/null
+++ b/sjplayer/src/sjplayer/ElementScheduledController.d
@@ -0,0 +1,94 @@
+/// License: MIT
+module sjplayer.ElementScheduledController;
+
+import std.traits,
+       std.typecons;
+
+import gl4d;
+
+import sjscript;
+
+import sjplayer.ElementInterface,
+       sjplayer.ScheduledControllerInterface,
+       sjplayer.VarStoreInterface,
+       sjplayer.util.MatrixFactory,
+       sjplayer.util.Parameter;
+
+///
+class ElementScheduledController(
+    Element, string[string] ParameterNameMap) :
+  AbstractScheduledControllerWithOperationImpl
+  if (is(Element : ElementInterface)) {
+ public:
+  ///
+  enum AliveManagementAvailable =
+    is(typeof((Element e) => e.alive)) &&
+    is(ReturnType!((Element e) => e.alive) == bool);
+  ///
+  enum MatrixModificationAvailable =
+    is(typeof((Element e) => e.matrix)) &&
+    is(ReturnType!((Element e) => e.matrix) == mat3);
+
+  ///
+  this(
+      Element element,
+      in VarStoreInterface varstore,
+      in ParametersBlock[] operations) {
+    super(varstore, operations);
+    element_ = element;
+  }
+
+ protected:
+  override void PrepareOperation(ref in ParametersBlock params) {
+    element_.Initialize();
+    static if (AliveManagementAvailable) {
+      element_.alive = true;
+    }
+    static if (MatrixModificationAvailable) {
+      matrix_factory_ = matrix_factory_.init;
+    }
+    super.PrepareOperation(params);
+  }
+  override void ProcessOperation(float time, ref in ParametersBlock params) {
+    super.ProcessOperation(time, params);
+    static if (MatrixModificationAvailable) {
+      element_.matrix = matrix_factory_.Create().transposed;
+    }
+  }
+  override void FinalizeOperation(ref in ParametersBlock params) {
+    static if (AliveManagementAvailable) {
+      element_.alive = false;
+    }
+  }
+
+  override float GetVariable(string name) const {
+    switch (name) {
+      static foreach (map_name, code; ParameterNameMap) {
+        case map_name:
+          return mixin("element_."~code);
+      }
+      default: return super.GetVariable(name);
+    }
+  }
+  override void SetParameter(Nullable!float time, ref in Parameter param) {
+    auto vars = VarStore(this, time);
+    switch (param.name) {
+      static foreach (map_name, code; ParameterNameMap) {
+        case map_name:
+          param.CalculateParameter(mixin("element_."~code), vars);
+          return;
+      }
+      default:
+    }
+    static if (MatrixModificationAvailable) {
+      if (param.CalculateMatrixParameter(matrix_factory_, vars)) return;
+    }
+    super.SetParameter(time, param);
+  }
+
+  Element element_;
+
+  static if (MatrixModificationAvailable) {
+    MatrixFactory matrix_factory_;
+  }
+}