com.jme3.anim.tween.action.BaseAction: basic javadoc (#2020)

Provides basic JavaDoc for the class com.jme3.anim.tween.action.BaseAction.

Author: pavly-gerges

jme3-core/src/main/java/com/jme3/anim/tween/action/BaseAction.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2009-2022 jMonkeyEngine
+ * Copyright (c) 2009-2024 jMonkeyEngine
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -35,14 +35,40 @@
 import com.jme3.anim.tween.ContainsTweens;
 import com.jme3.anim.tween.Tween;
 import com.jme3.util.SafeArrayList;
-
 import java.util.List;
 
+/**
+ * A simple implementation for the abstract class {@link Action} to provide a wrapper for a {@link Tween}.
+ * Internally, it is used as a helper class for {@link Action} to extract and gather actions from a tween and interpolate it.
+ * <p>
+ * An example showing two clip actions running in parallel at 2x of their ordinary speed
+ * by the help of BaseAction on a new Animation Layer :
+ * <pre class="prettyprint">
+ * //create a base action from a tween.
+ * final BaseAction action = new BaseAction(Tweens.parallel(clipAction0, clipAction1));
+ * //set the action properties - utilized within the #{@link Action} class.
+ * baseAction.setSpeed(2f);
+ * //register the action as an observer to the animComposer control.
+ * animComposer.addAction("basicAction", action);
+ * //make a new Layer for a basic armature mask
+ * animComposer.makeLayer(ActionState.class.getSimpleName(), new ArmatureMask());
+ * //run the action within this layer
+ * animComposer.setCurrentAction("basicAction", ActionState.class.getSimpleName());
+ * </pre>
+ * </p>
+ * Created by Nehon.
+ */
 public class BaseAction extends Action {
 
     final private Tween tween;
     private boolean maskPropagationEnabled = true;
 
+    /**
+     * Instantiates an action from a tween by extracting the actions from a tween
+     * to a list of sub-actions to be interpolated later.
+     *
+     * @param tween a tween to extract the actions from (not null).
+     */
     public BaseAction(Tween tween) {
         this.tween = tween;
         setLength(tween.getLength());
@@ -52,33 +78,35 @@ public BaseAction(Tween tween) {
         subActions.toArray(actions);
     }
 
-    private void gatherActions(Tween tween, List<Action> subActions) {
-        if (tween instanceof Action) {
-            subActions.add((Action) tween);
-        } else if (tween instanceof ContainsTweens) {
-            Tween[] tweens = ((ContainsTweens) tween).getTweens();
-            for (Tween t : tweens) {
-                gatherActions(t, subActions);
-            }
-        }
-    }
-
     /**
-     * @return true if mask propagation to child actions is enabled else returns false
+     * Tests whether the animation mask is applied to the wrapped actions {@link BaseAction#actions}.
+     *
+     * @return true if mask propagation to child actions is enabled else returns false.
      */
     public boolean isMaskPropagationEnabled() {
         return maskPropagationEnabled;
     }
 
     /**
+     * Determines whether to apply the animation mask to the wrapped or child actions {@link BaseAction#actions}.
      *
      * @param maskPropagationEnabled If true, then mask set by AnimLayer will be
-     *                               forwarded to all child actions (Default=true)
+     *                               forwarded to all child actions (Default=true).
      */
     public void setMaskPropagationEnabled(boolean maskPropagationEnabled) {
         this.maskPropagationEnabled = maskPropagationEnabled;
     }
 
+    /**
+     * Sets the animation mask which determines which part of the model will 
+     * be animated by the animation layer. If the {@link BaseAction#isMaskPropagationEnabled()} is false, setting
+     * the mask attribute will not affect the actions under this base action. Setting this to 'null' will animate
+     * the entire model.
+     *
+     * @param mask an animation mask to be applied to this action (nullable).
+     * @see com.jme3.anim.AnimLayer to adjust the animation mask to control which part will be animated
+     * @see BaseAction#setMaskPropagationEnabled(boolean)
+     */
     @Override
     public void setMask(AnimationMask mask) {
         super.setMask(mask);
@@ -94,4 +122,21 @@ public void setMask(AnimationMask mask) {
     public boolean interpolate(double t) {
         return tween.interpolate(t);
     }
+    
+    /**
+     * Extracts the actions from a tween into a list.
+     *
+     * @param tween      the tween to extract the actions from (not null).
+     * @param subActions a collection to gather the extracted actions (not null).
+     */
+    private void gatherActions(Tween tween, List<Action> subActions) {
+        if (tween instanceof Action) {
+            subActions.add((Action) tween);
+        } else if (tween instanceof ContainsTweens) {
+            Tween[] tweens = ((ContainsTweens) tween).getTweens();
+            for (Tween t : tweens) {
+                gatherActions(t, subActions);
+            }
+        }
+    }
 }