Database: added "opt_****" fields in Admin table. Tango: optimized mesh saved in database for quick open, open menu shows preview images. util3d::mergeTextures() return all textures in same cv::Mat.

app/android/src/com/introlab/rtabmap/Util.java

@@ -90,4 +90,37 @@ public class Util {
 		return fileList;
 	}
 	
+	/**
+	 * https://stackoverflow.com/questions/6701948/efficient-way-to-compare-version-strings-in-java
+	 * Compares two version strings. 
+	 * 
+	 * Use this instead of String.compareTo() for a non-lexicographical 
+	 * comparison that works for version strings. e.g. "1.10".compareTo("1.6").
+	 * 
+	 * @note It does not work if "1.10" is supposed to be equal to "1.10.0".
+	 * 
+	 * @param str1 a string of ordinal numbers separated by decimal points. 
+	 * @param str2 a string of ordinal numbers separated by decimal points.
+	 * @return The result is a negative integer if str1 is _numerically_ less than str2. 
+	 *         The result is a positive integer if str1 is _numerically_ greater than str2. 
+	 *         The result is zero if the strings are _numerically_ equal.
+	 */
+	public static int versionCompare(String str1, String str2) {
+	    String[] vals1 = str1.split("\\.");
+	    String[] vals2 = str2.split("\\.");
+	    int i = 0;
+	    // set index to first non-equal ordinal or length of shortest version string
+	    while (i < vals1.length && i < vals2.length && vals1[i].equals(vals2[i])) {
+	      i++;
+	    }
+	    // compare first non-equal ordinal number
+	    if (i < vals1.length && i < vals2.length) {
+	        int diff = Integer.valueOf(vals1[i]).compareTo(Integer.valueOf(vals2[i]));
+	        return Integer.signum(diff);
+	    }
+	    // the strings are equal or one string is a substring of the other
+	    // e.g. "1.2.3" = "1.2.3" or "1.2.3" < "1.2.3.4"
+	    return Integer.signum(vals1.length - vals2.length);
+	}
+	
 }