add xml attributes for combobox node and add resolution selection for new doc

engine/util.cpp

@@ -88,6 +88,23 @@ glm::vec3 convert_rgb2hsv(const glm::vec3 c)
     return glm::vec3(fabs(q.z + (q.w - q.y) / (6.0 * d + e)), d / (q.x + e), q.x);
 }
 
+std::vector<std::string> split(const std::string& subject, char d, int max_split/* = 0*/)
+{
+    std::vector<std::string> ret;
+    int start = 0;
+    int n = subject.find_first_of(d);
+    while (n != std::string::npos)
+    {
+        ret.push_back(subject.substr(start, n - start));
+        start = n + 1;
+        if (max_split && ret.size() == max_split)
+            break;
+        n = subject.find_first_of(d, start);
+    }
+    ret.push_back(subject.substr(start));
+    return ret;
+}
+
 static const char* gl2str(GLenum err)
 {
     switch (err)