Documentation
Complete guide to implementing and working with the General Traffic Signal Specification (GTSS).
phases.txt
phases.txt defines phases and the lane and movement type through the intersection, number of lanes, compass bearing of the approach and the posted speed limit.
phase
phase is a unique identifier for each phase of a traffic signal. It is used to reference the phase in other GTSS files.
signal_id
signal_id is a unique agency specific identifier for each traffic signal. It is used to reference the signal in other GTSS files.
movement_type
movement_type describes the type of movement allowed during the phase, such as “L” for Left Turn, “T” for through. Additional Encodings shown in table below.
| Encoding | Phase Movement |
|---|---|
| T | Through |
| L | Left |
| LT | Left Through Shared Lane |
| TL | Permissive Left |
| FYA | Flashing Yellow Arrow |
| U | U-Turn |
| R | Right Turn |
| TR | Through Right |
| PED | Pedestrian |
num_of_lanes
num_of_lanes indicates the number of lanes available at the stop bar for the movement during the phase.
compass_bearing
compass_bearing indicates the compass bearing of the approach to the intersection, expressed in degrees (0-360).
posted_speed
posted_speed indicates the posted speed limit for the approach to the intersection, expressed in miles per hour (mph).
is_overlap
is_overlap is a boolean value indicating whether the phase overlaps with another phase. It is used to manage simultaneous movements at the intersection.
Example
phase,signal_id,movement_type,num_of_lanes,compass_bearing,posted_speed,is_overlap
1,1,L,2,90,35,false