Feature: appending user defined UV sets to the mesh even if they are not

directly used by the model.

jme3-blender/src/main/java/com/jme3/scene/plugins/blender/materials/MaterialContext.java

@@ -1,6 +1,7 @@
 package com.jme3.scene.plugins.blender.materials;
 
 import java.io.IOException;
+import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
@@ -157,14 +158,14 @@ public final class MaterialContext implements Savable {
         }
 
         // applying textures
+        int textureIndex = 0;
         if (loadedTextures != null && loadedTextures.size() > 0) {
-            int textureIndex = 0;
             if (loadedTextures.size() > TextureHelper.TEXCOORD_TYPES.length) {
                 LOGGER.log(Level.WARNING, "The blender file has defined more than {0} different textures. JME supports only {0} UV mappings.", TextureHelper.TEXCOORD_TYPES.length);
             }
             for (CombinedTexture combinedTexture : loadedTextures) {
                 if (textureIndex < TextureHelper.TEXCOORD_TYPES.length) {
-                    combinedTexture.flatten(geometry, geometriesOMA, userDefinedUVCoordinates, blenderContext);
+                    String usedUserUVSet = combinedTexture.flatten(geometry, geometriesOMA, userDefinedUVCoordinates, blenderContext);
 
                     this.setTexture(material, combinedTexture.getMappingType(), combinedTexture.getResultTexture());
                     List<Vector2f> uvs = combinedTexture.getResultUVS();
@@ -173,13 +174,19 @@ public final class MaterialContext implements Savable {
                         uvCoordsBuffer.setupData(Usage.Static, 2, Format.Float, BufferUtils.createFloatBuffer(uvs.toArray(new Vector2f[uvs.size()])));
                         geometry.getMesh().setBuffer(uvCoordsBuffer);
                     }//uvs might be null if the user assigned non existing UV coordinates group name to the mesh (this should be fixed in blender file)
+                    
+                    if(usedUserUVSet != null) {
+                    	userDefinedUVCoordinates = new HashMap<>(userDefinedUVCoordinates);
+                    	userDefinedUVCoordinates.remove(usedUserUVSet);
+                    }
                 } else {
                     LOGGER.log(Level.WARNING, "The texture could not be applied because JME only supports up to {0} different UV's.", TextureHelper.TEXCOORD_TYPES.length);
                 }
             }
-        } else if (userDefinedUVCoordinates != null && userDefinedUVCoordinates.size() > 0) {
-            LOGGER.fine("No textures found for the mesh, but UV coordinates are applied.");
-            int textureIndex = 0;
+        }
+
+        if (userDefinedUVCoordinates != null && userDefinedUVCoordinates.size() > 0) {
+            LOGGER.fine("Storing unused, user defined UV coordinates sets.");
             if (userDefinedUVCoordinates.size() > TextureHelper.TEXCOORD_TYPES.length) {
                 LOGGER.log(Level.WARNING, "The blender file has defined more than {0} different UV coordinates for the mesh. JME supports only {0} UV coordinates buffers.", TextureHelper.TEXCOORD_TYPES.length);
             }
@@ -190,7 +197,9 @@ public final class MaterialContext implements Savable {
                     uvCoordsBuffer.setupData(Usage.Static, 2, Format.Float, BufferUtils.createFloatBuffer(uvs.toArray(new Vector2f[uvs.size()])));
                     geometry.getMesh().setBuffer(uvCoordsBuffer);
                 } else {
-                    LOGGER.log(Level.WARNING, "The texture could not be applied because JME only supports up to {0} different UV's.", TextureHelper.TEXCOORD_TYPES.length);
+                    LOGGER.log(Level.WARNING, "The user's UV set named: '{0}' could not be stored because JME only supports up to {1} different UV's.", new Object[] {
+                		entry.getKey(), TextureHelper.TEXCOORD_TYPES.length
+                    });
                 }
             }
         }

jme3-blender/src/main/java/com/jme3/scene/plugins/blender/textures/CombinedTexture.java

@@ -119,22 +119,24 @@ public class CombinedTexture {
         }
     }
 
-    /**
-     * This method flattens the texture and creates a single result of Texture2D
-     * type.
-     * 
-     * @param geometry
-     *            the geometry the texture is created for
-     * @param geometriesOMA
-     *            the old memory address of the geometries list that the given
-     *            geometry belongs to (needed for bounding box creation)
-     * @param userDefinedUVCoordinates
-     *            the UV's defined by user (null or zero length table if none
-     *            were defined)
-     * @param blenderContext
-     *            the blender context
-     */
-    public void flatten(Geometry geometry, Long geometriesOMA, Map<String, List<Vector2f>> userDefinedUVCoordinates, BlenderContext blenderContext) {
+	/**
+	 * This method flattens the texture and creates a single result of Texture2D
+	 * type.
+	 * 
+	 * @param geometry
+	 *            the geometry the texture is created for
+	 * @param geometriesOMA
+	 *            the old memory address of the geometries list that the given
+	 *            geometry belongs to (needed for bounding box creation)
+	 * @param userDefinedUVCoordinates
+	 *            the UV's defined by user (null or zero length table if none
+	 *            were defined)
+	 * @param blenderContext
+	 *            the blender context
+	 * @return the name of the user UV coordinates used (null if the UV's were
+	 *         generated)
+	 */
+    public String flatten(Geometry geometry, Long geometriesOMA, Map<String, List<Vector2f>> userDefinedUVCoordinates, BlenderContext blenderContext) {
         Mesh mesh = geometry.getMesh();
         Texture previousTexture = null;
         UVCoordinatesType masterUVCoordinatesType = null;
@@ -226,6 +228,7 @@ public class CombinedTexture {
             }
             resultUVS = ((TriangulatedTexture) resultTexture).getResultUVS();
             resultTexture = ((TriangulatedTexture) resultTexture).getResultTexture();
+            masterUserUVSetName = null;
         }
 
         // setting additional data
@@ -234,6 +237,8 @@ public class CombinedTexture {
         // otherwise ugly lines appear between the mesh faces
         resultTexture.setMagFilter(MagFilter.Nearest);
         resultTexture.setMinFilter(MinFilter.NearestNoMipMaps);
+        
+        return masterUserUVSetName;
     }
 
     /**