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

engine/util.h

@@ -15,6 +15,7 @@ bool segments_intersect(const glm::vec2& p0a, const glm::vec2& p0b,
 glm::vec4 rand_color();
 glm::vec3 convert_hsv2rgb(const glm::vec3 c);
 glm::vec3 convert_rgb2hsv(const glm::vec3 c);
+std::vector<std::string> split(const std::string& subject, char d, int max_split = 0);
 
 size_t curl_data_handler(void *contents, size_t size, size_t nmemb, void *userp);
 size_t curl_data_write(void *ptr, size_t size, size_t nmemb, FILE *stream);