#define TOOL_BREAK    1 /* break at intersection */
#define TOOL_RMDUPL   2 /* remove duplicates */
#define TOOL_RMDANGLE 3 /* remove dangles */
#define TOOL_CHDANGLE 4 /* retype 'boundary' dangles to 'line' */
#define TOOL_SNAP     5 /* snap line to vertex in threshold */
#define TOOL_RMDAC    6 /* remove duplicate area centroids */
#define TOOL_BPOL     7 /* break polygons on shared points with different angles */
#define TOOL_RMBRIDGE 8 /* remove bridges connecting area and island or 2 islands */
#define TOOL_CHBRIDGE 9 /* change the type of bridges connecting area and island or 2 islands from boundary to line */
#define TOOL_PRUNE   10 /* remove vertices in threshold from lines and boundaries */
#define TOOL_RMAREA  11 /* remove small areas */
#define TOOL_RMSA    12 /* remove small angles between lines at nodes */