If a specific key is pressed (once to change the mode or for each line) in the middle of the line should be appeare a label with the measured distance (default: pixel, but if a scale reference was provided , then this value with the user-defined unit).
If a specific key is pressed (once to change the mode or for each line) in the middle of the line should be appeare a label with the measured distance (default: pixel, but if a scale reference was provided , then this value with the user-defined unit).