DragControls: Add mouseButtons

docs/examples/en/controls/DragControls.html

@@ -100,6 +100,18 @@ <h3>[property:Boolean enabled]</h3>
 			Whether or not the controls are enabled.
 		</p>
 
+		<h3>[property:Object mouseButtons]</h3>
+		<p>
+			This object contains references to the mouse button used by the controls. 
+			<code>
+				controls.mouseButtons = {
+					LEFT: true,
+					MIDDLE: true,
+					RIGHT: true
+				}
+			</code>
+		</p>
+
 		<h3>[property:Boolean recursive]</h3>
 		<p>
 			Whether children of draggable objects can be dragged independently from their parent. Default is `true`.

docs/examples/zh/controls/DragControls.html

@@ -102,14 +102,31 @@ <h3>[property:Boolean enabled]</h3>
 			是否启用控制器。
 		</p>
 
+		<h3>[property:Object mouseButtons]</h3>
+		<p>
+			鼠标事件中允许响应的按键。 
+			<code>
+				controls.mouseButtons = {
+					LEFT: true,
+					MIDDLE: true,
+					RIGHT: true
+				}
+			</code>
+		</p>
+
+		<h3>[property:Boolean recursive]</h3>
+		<p>
+			可拖动对象的子对象是否可以独立于其父对象进行拖动。默认值为 `true`。
+		</p>
+
 		<h3>[property:Boolean transformGroup]</h3>
 		<p>
 			当[page:DragControls.objects]数组包含一个单个可拖拽的组对象时该选项生效。如果设置为`true`，[name]会转换整个组对象，而不对单个对象做转换。默认值为`false`。
 		</p>
 
 		<h3>[property:String mode]</h3>
 		<p>
-			The current transformation mode. Possible values are `translate`, and `rotate`. Default is `translate`.
+			当前的变换模式，该值可以是 `translate` 或 `rotate`。 默认值为 `translate`。
 		</p>
 
 		<h2>方法</h2>
@@ -143,7 +160,7 @@ <h3>[method:Raycaster getRaycaster] ()</h3>
 
 		<h3>[method:undefined setObjects] ( [param:Array objects] )</h3>
 		<p>
-			Sets an array of draggable objects by overwriting the existing one.
+			通过覆盖现有数组来设置可拖动对象数组。
 		</p>
 
 		<h2>源代码</h2>

examples/jsm/controls/DragControls.js

@@ -37,7 +37,7 @@ class DragControls extends EventDispatcher {
 
 		this.rotateSpeed = 1;
 
-		//
+		this.mouseButtons = { LEFT: true, MIDDLE: true, RIGHT: true };
 
 		const scope = this;
 
@@ -89,6 +89,45 @@ class DragControls extends EventDispatcher {
 
 			if ( scope.enabled === false ) return;
 
+			if ( event.pointerType === 'mouse' ) {
+
+				switch ( event.buttons ) {
+
+					case 1:
+
+						if ( scope.mouseButtons.LEFT !== true ) {
+
+							return;
+
+						}
+
+						break;
+					case 2:
+
+						if ( scope.mouseButtons.RIGHT !== true ) {
+
+							return;
+
+						}
+
+						break;
+					case 4:
+
+						if ( scope.mouseButtons.MIDDLE !== true ) {
+
+							return;
+
+						}
+
+						break;
+					default:
+
+						break;
+
+				}
+
+			}
+
 			updatePointer( event );
 
 			_raycaster.setFromCamera( _pointer, _camera );
@@ -175,6 +214,45 @@ class DragControls extends EventDispatcher {
 
 			if ( scope.enabled === false ) return;
 
+			if ( event.pointerType === 'mouse' ) {
+
+				switch ( event.button ) {
+
+					case 0:
+
+						if ( scope.mouseButtons.LEFT !== true ) {
+
+							return;
+
+						}
+
+						break;
+					case 1:
+
+						if ( scope.mouseButtons.MIDDLE !== true ) {
+
+							return;
+
+						}
+
+						break;
+					case 2:
+
+						if ( scope.mouseButtons.RIGHT !== true ) {
+
+							return;
+
+						}
+
+						break;
+					default:
+
+						break;
+
+				}
+
+			}
+
 			updatePointer( event );
 
 			_intersections.length = 0;