Feature: added support for 'Maintain volume' constraint.

git-svn-id: https://jmonkeyengine.googlecode.com/svn/trunk@11068 75d07b2b-3a1a-0410-a2c5-0572b91ccdca

engine/src/blender/com/jme3/scene/plugins/blender/constraints/definitions/ConstraintDefinitionFactory.java

@@ -52,6 +52,7 @@ public class ConstraintDefinitionFactory {
         CONSTRAINT_CLASSES.put("bSizeLimitConstraint", ConstraintDefinitionSizeLimit.class);
         CONSTRAINT_CLASSES.put("bKinematicConstraint", ConstraintDefinitionIK.class);
         CONSTRAINT_CLASSES.put("bTransLikeConstraint", ConstraintDefinitionTransLike.class);// since blender 2.51
+        CONSTRAINT_CLASSES.put("bSameVolumeConstraint", ConstraintDefinitionMaintainVolume.class);// since blender 2.53
     }
 
     private static final Map<String, String>                                UNSUPPORTED_CONSTRAINTS = new HashMap<String, String>();
@@ -73,7 +74,6 @@ public class ConstraintDefinitionFactory {
         UNSUPPORTED_CONSTRAINTS.put("bPivotConstraint", "Pivot");
         // Blender 2.56+
         UNSUPPORTED_CONSTRAINTS.put("bTrackToConstraint", "Track to");
-        UNSUPPORTED_CONSTRAINTS.put("bSameVolumeConstraint", "Same volume");
         // Blender 2.62+
         UNSUPPORTED_CONSTRAINTS.put("bCameraSolverConstraint", "Camera solver");
         UNSUPPORTED_CONSTRAINTS.put("bObjectSolverConstraint", "Object solver");

engine/src/blender/com/jme3/scene/plugins/blender/constraints/definitions/ConstraintDefinitionMaintainVolume.java

@@ -0,0 +1,45 @@
+package com.jme3.scene.plugins.blender.constraints.definitions;
+
+import com.jme3.math.Transform;
+import com.jme3.scene.plugins.blender.BlenderContext;
+import com.jme3.scene.plugins.blender.constraints.ConstraintHelper.Space;
+import com.jme3.scene.plugins.blender.file.Structure;
+
+public class ConstraintDefinitionMaintainVolume extends ConstraintDefinition {
+    private static final int FLAG_MASK_X = 0;
+    private static final int FLAG_MASK_Y = 1;
+    private static final int FLAG_MASK_Z = 2;
+
+    private float            volume;
+
+    public ConstraintDefinitionMaintainVolume(Structure constraintData, Long ownerOMA, BlenderContext blenderContext) {
+        super(constraintData, ownerOMA, blenderContext);
+        volume = (float) Math.sqrt(((Number) constraintData.getFieldValue("volume")).floatValue());
+    }
+
+    @Override
+    public void bake(Space ownerSpace, Space targetSpace, Transform targetTransform, float influence) {
+        if (volume != 1 && influence > 0) {
+            Transform ownerTransform = this.getOwnerTransform(ownerSpace);
+            switch (flag) {
+                case FLAG_MASK_X:
+                    ownerTransform.getScale().multLocal(1, volume, volume);
+                    break;
+                case FLAG_MASK_Y:
+                    ownerTransform.getScale().multLocal(volume, 1, volume);
+                    break;
+                case FLAG_MASK_Z:
+                    ownerTransform.getScale().multLocal(volume, volume, 1);
+                    break;
+                default:
+                    throw new IllegalStateException("Unknown flag value: " + flag);
+            }
+            this.applyOwnerTransform(ownerTransform, ownerSpace);
+        }
+    }
+
+    @Override
+    public String getConstraintTypeName() {
+        return "Maintain volume";
+    }
+}