use abstract merge strategy to extract duplicated code

src/layer/abstract/MergedLayer3d.js

@@ -68,7 +68,7 @@ function MergedLayer3d( config ) {
 	 * Initialized in MergedLayer3d's initStrategy period.
 	 * Applicable strategy: Add3d, Average3d, Concatenate3d, Dot3d, Maximum3d, Multiply3d, Subtract3d.
 	 *
-	 * @type { Object }, Strategy3d
+	 * @type { Object }, MergeStrategy3d
 	 */
 
 	this.operationStrategy = undefined;

src/merge/abstract/Strategy1d.js → src/merge/abstract/MergeStrategy.js

@@ -2,14 +2,14 @@
  * @author syt123450 / https://github.com/syt123450
  */
 
-function Strategy1d( mergedElements ) {
+function MergeStrategy( mergedElements ) {
 
 	this.mergedElements = mergedElements;
 	this.layerIndex = undefined;
 
 }
 
-Strategy1d.prototype = {
+MergeStrategy.prototype = {
 
 	setLayerIndex: function( layerIndex ) {
 
@@ -25,7 +25,7 @@ Strategy1d.prototype = {
 
 	getOutputShape: function() {
 
-		return [ 1 ];
+		return undefined;
 
 	},
 
@@ -42,4 +42,4 @@ Strategy1d.prototype = {
 
 };
 
-export { Strategy1d };
+export { MergeStrategy };

src/merge/abstract/MergeStrategy1d.js

@@ -0,0 +1,23 @@
+/**
+ * @author syt123450 / https://github.com/syt123450
+ */
+
+import { MergeStrategy } from "./MergeStrategy";
+
+function MergeStrategy1d( mergedElements ) {
+
+	MergeStrategy.call( this, mergedElements );
+
+}
+
+MergeStrategy1d.prototype = Object.assign( Object.create( MergeStrategy.prototype ), {
+
+	getOutputShape: function() {
+
+		return [ 1 ];
+
+	}
+
+} );
+
+export { MergeStrategy1d };

src/merge/abstract/MergeStrategy2d.js

@@ -0,0 +1,23 @@
+/**
+ * @author syt123450 / https://github.com/syt123450
+ */
+
+import { MergeStrategy } from "./MergeStrategy";
+
+function MergeStrategy2d( mergedElements ) {
+
+	MergeStrategy.call( this, mergedElements );
+
+}
+
+MergeStrategy2d.prototype = Object.assign( Object.create( MergeStrategy.prototype ), {
+
+	getOutputShape: function() {
+
+		return [ 1, 1 ];
+
+	}
+
+} );
+
+export { MergeStrategy2d };

src/merge/abstract/MergeStrategy3d.js

@@ -0,0 +1,23 @@
+/**
+ * @author syt123450 / https://github.com/syt123450
+ */
+
+import { MergeStrategy } from "./MergeStrategy";
+
+function MergeStrategy3d( mergedElements ) {
+
+	MergeStrategy.call( this, mergedElements );
+
+}
+
+MergeStrategy3d.prototype = Object.assign( Object.create( MergeStrategy.prototype ), {
+
+	getOutputShape: function() {
+
+		return [ 1, 1, 1 ];
+
+	}
+
+} );
+
+export { MergeStrategy3d };

src/merge/abstract/StableMerge1d.js

@@ -2,15 +2,15 @@
  * @author syt123450 / https://github.com/syt123450
  */
 
-import { Strategy1d } from "./Strategy1d";
+import { MergeStrategy1d } from "./MergeStrategy1d";
 
 function StableMerge1d( mergedElements ) {
 
-	Strategy1d.call( this, mergedElements );
+	MergeStrategy1d.call( this, mergedElements );
 
 }
 
-StableMerge1d.prototype = Object.assign( Object.create( Strategy1d.prototype ), {
+StableMerge1d.prototype = Object.assign( Object.create( MergeStrategy1d.prototype ), {
 
 	validate: function() {
 

src/merge/abstract/StableMerge2d.js

@@ -2,15 +2,15 @@
  * @author syt123450 / https://github.com/syt123450
  */
 
-import { Strategy2d } from "./Strategy2d";
+import { MergeStrategy2d } from "./MergeStrategy2d";
 
 function StableMerge2d( mergedElements ) {
 
-	Strategy2d.call( this, mergedElements );
+	MergeStrategy2d.call( this, mergedElements );
 
 }
 
-StableMerge2d.prototype = Object.assign( Object.create( Strategy2d.prototype ), {
+StableMerge2d.prototype = Object.assign( Object.create( MergeStrategy2d.prototype ), {
 
 	validate: function() {
 

src/merge/abstract/StableMerge3d.js

@@ -2,15 +2,15 @@
  * @author syt123450 / https://github.com/syt123450
  */
 
-import { Strategy3d } from "./Strategy3d";
+import { MergeStrategy3d } from "./MergeStrategy3d";
 
 function StableMerge3d( mergedElements ) {
 
-	Strategy3d.call( this, mergedElements );
+	MergeStrategy3d.call( this, mergedElements );
 
 }
 
-StableMerge3d.prototype = Object.assign( Object.create( Strategy3d.prototype ), {
+StableMerge3d.prototype = Object.assign( Object.create( MergeStrategy3d.prototype ), {
 
 	validate: function() {
 

src/merge/strategy/Concatenate1d.js

@@ -1,14 +1,18 @@
-import { Strategy1d } from "../abstract/Strategy1d";
+/**
+ * @author syt123450 / https://github.com/syt123450
+ */
+
+import { MergeStrategy1d } from "../abstract/MergeStrategy1d";
 
 function Concatenate1d( mergedElements ) {
 
-	Strategy1d.call( this, mergedElements );
+	MergeStrategy1d.call( this, mergedElements );
 
 	this.strategyType = "Concatenate1d";
 
 }
 
-Concatenate1d.prototype = Object.assign( Object.create( Strategy1d.prototype ), {
+Concatenate1d.prototype = Object.assign( Object.create( MergeStrategy1d.prototype ), {
 
 	validate: function() {
 

src/merge/strategy/Concatenate2d.js

@@ -1,14 +1,18 @@
-import { Strategy2d } from "../abstract/Strategy2d";
+/**
+ * @author syt123450 / https://github.com/syt123450
+ */
+
+import { MergeStrategy2d } from "../abstract/MergeStrategy2d";
 
 function Concatenate2d( mergedElements ) {
 
-	Strategy2d.call( this, mergedElements );
+	MergeStrategy2d.call( this, mergedElements );
 
 	this.strategyType = "Concatenate2d";
 
 }
 
-Concatenate2d.prototype = Object.assign( Object.create( Strategy2d.prototype ), {
+Concatenate2d.prototype = Object.assign( Object.create( MergeStrategy2d.prototype ), {
 
 	validate: function() {
 

src/merge/strategy/Concatenate3d.js

@@ -2,17 +2,17 @@
  * @author syt123450 / https://github.com/syt123450
  */
 
-import { Strategy3d } from "../abstract/Strategy3d";
+import { MergeStrategy3d } from "../abstract/MergeStrategy3d";
 
 function Concatenate3d( mergedElements ) {
 
-	Strategy3d.call( this, mergedElements );
+	MergeStrategy3d.call( this, mergedElements );
 
 	this.strategyType = "Concatenate3d";
 
 }
 
-Concatenate3d.prototype = Object.assign( Object.create( Strategy3d.prototype ), {
+Concatenate3d.prototype = Object.assign( Object.create( MergeStrategy3d.prototype ), {
 
 	validate: function() {