Adds SingleLayerInfluenceMask (#2043)

Checks if a joint is currently being used by a higher layer before approving it for personal use via contains(Object target). This can help smooth some interpolation issues that may arise between layers with looped/sequenced animations

Author: codex128

jme3-core/src/main/java/com/jme3/anim/SingleLayerInfluenceMask.java

@@ -0,0 +1,218 @@
+/*
+ * Copyright (c) 2024 jMonkeyEngine
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * * Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ *
+ * * Neither the name of 'jMonkeyEngine' nor the names of its contributors
+ *   may be used to endorse or promote products derived from this software
+ *   without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package com.jme3.anim;
+
+import com.jme3.scene.Spatial;
+
+/**
+ * Mask that excludes joints from participating in the layer
+ * if a higher layer is using those joints in an animation.
+ * 
+ * @author codex
+ */
+public class SingleLayerInfluenceMask extends ArmatureMask {
+    
+    private final String layer;
+    private final AnimComposer anim;
+    private final SkinningControl skin;
+    private boolean checkUpperLayers = true;
+    
+    /**
+     * @param layer The layer this mask is targeted for. It is important
+     * that this match the name of the layer this mask is (or will be) part of. You
+     * can use {@link makeLayer} to ensure this.
+     * @param spatial Spatial containing necessary controls ({@link AnimComposer} and {@link SkinningControl})
+     */
+    public SingleLayerInfluenceMask(String layer, Spatial spatial) {
+        super();
+        this.layer = layer;
+        anim = spatial.getControl(AnimComposer.class);
+        skin = spatial.getControl(SkinningControl.class);
+    }
+    /**
+     * @param layer The layer this mask is targeted for. It is important
+     * that this match the name of the layer this mask is (or will be) part of. You
+     * can use {@link makeLayer} to ensure this.
+     * @param anim anim composer this mask is assigned to
+     * @param skin skinning control complimenting the anim composer.
+     */
+    public SingleLayerInfluenceMask(String layer, AnimComposer anim, SkinningControl skin) {
+        super();
+        this.layer = layer;
+        this.anim = anim;
+        this.skin = skin;
+    }
+    
+    /**
+     * Makes a layer from this mask.
+     */
+    public void makeLayer() {
+        anim.makeLayer(layer, this);
+    }
+    
+    /**
+     * Adds all joints to this mask.
+     * @return this.instance
+     */
+    public SingleLayerInfluenceMask addAll() {
+        for (Joint j : skin.getArmature().getJointList()) {
+            super.addBones(skin.getArmature(), j.getName());
+        }
+        return this;
+    }
+    
+    /**
+     * Adds the given joint and all its children to this mask.
+     * @param joint
+     * @return this instance
+     */
+    public SingleLayerInfluenceMask addFromJoint(String joint) {
+        super.addFromJoint(skin.getArmature(), joint);
+        return this;
+    }
+    
+    /**
+     * Adds the given joints to this mask.
+     * @param joints
+     * @return this instance
+     */
+    public SingleLayerInfluenceMask addJoints(String... joints) {
+        super.addBones(skin.getArmature(), joints);
+        return this;
+    }
+    
+    /**
+     * Makes this mask check if each joint is being used by a higher layer
+     * before it uses them.
+     * <p>Not checking is more efficient, but checking can avoid some
+     * interpolation issues between layers. Default=true
+     * @param check 
+     * @return this instance
+     */
+    public SingleLayerInfluenceMask setCheckUpperLayers(boolean check) {
+        checkUpperLayers = check;
+        return this;
+    }
+    
+    /**
+     * Get the layer this mask is targeted for.
+     * <p>It is extremely important that this value match the actual layer
+     * this is included in, because checking upper layers may not work if
+     * they are different.
+     * @return target layer
+     */
+    public String getTargetLayer() {
+        return layer;
+    }
+    
+    /**
+     * Get the {@link AnimComposer} this mask is for.
+     * @return anim composer
+     */
+    public AnimComposer getAnimComposer() {
+        return anim;
+    }
+    
+    /**
+     * Get the {@link SkinningControl} this mask is for.
+     * @return skinning control
+     */
+    public SkinningControl getSkinningControl() {
+        return skin;
+    }
+    
+    /**
+     * Returns true if this mask is checking upper layers for joint use.
+     * @return 
+     */
+    public boolean isCheckUpperLayers() {
+        return checkUpperLayers;
+    }
+    
+    @Override
+    public boolean contains(Object target) {
+        return simpleContains(target) && (!checkUpperLayers || !isAffectedByUpperLayers(target));
+    }
+    
+    private boolean simpleContains(Object target) {
+        return super.contains(target);
+    }
+    
+    private boolean isAffectedByUpperLayers(Object target) {
+        boolean higher = false;
+        for (String name : anim.getLayerNames()) {
+            if (name.equals(layer)) {
+                higher = true;
+                continue;
+            }
+            if (!higher) {
+                continue;
+            }
+            AnimLayer lyr = anim.getLayer(name);  
+            // if there is no action playing, no joints are used, so we can skip
+            if (lyr.getCurrentAction() == null) continue;
+            if (lyr.getMask() instanceof SingleLayerInfluenceMask) {
+                // dodge some needless recursion by calling a simpler method
+                if (((SingleLayerInfluenceMask)lyr.getMask()).simpleContains(target)) {
+                    return true;
+                }
+            }
+            else if (lyr.getMask().contains(target)) {
+                return true;
+            }
+        }
+        return false;
+    }
+    
+    /**
+     * Creates an {@code SingleLayerInfluenceMask} for all joints.
+     * @param layer layer the returned mask is, or will be, be assigned to
+     * @param spatial spatial containing anim composer and skinning control
+     * @return new mask
+     */
+    public static SingleLayerInfluenceMask all(String layer, Spatial spatial) {
+        return new SingleLayerInfluenceMask(layer, spatial).addAll();
+    }
+    
+    /**
+     * Creates an {@code SingleLayerInfluenceMask} for all joints.
+     * @param layer layer the returned mask is, or will be, assigned to
+     * @param anim anim composer
+     * @param skin skinning control
+     * @return new mask
+     */
+    public static SingleLayerInfluenceMask all(String layer, AnimComposer anim, SkinningControl skin) {
+        return new SingleLayerInfluenceMask(layer, anim, skin).addAll();
+    }
+    
+}
+