diff options
Diffstat (limited to 'navit')
-rw-r--r-- | navit/attr.h | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/navit/attr.h b/navit/attr.h index 347df2112..60e3d5168 100644 --- a/navit/attr.h +++ b/navit/attr.h @@ -101,12 +101,21 @@ enum attr_format { #define ATTR_REL_MAXABS 0x40000000 #define ATTR_REL_RELSHIFT 0x60000000 +/** Indicates whether a position is valid **/ enum attr_position_valid { - attr_position_valid_invalid, - attr_position_valid_static, - attr_position_valid_extrapolated_time, - attr_position_valid_extrapolated_spatial, - attr_position_valid_valid, + attr_position_valid_invalid, /**< The position is invalid and should be discarded. **/ + attr_position_valid_static, /**< The position is valid but the vehicle is not moving, or moving very slowly. + Calculations that involve the difference between two consecutive positions, + such as bearing, may therefore be inaccurate. **/ + attr_position_valid_extrapolated_time, /**< FIXME: this description is just my (mvglasow) guess; this value is not used anywhere as of r5957. + The position is the vehicle's last known position, and the consumer of the + information should be aware that the vehicle may have moved since. **/ + attr_position_valid_extrapolated_spatial, /**< FIXME: this description is just my (mvglasow) guess; this value is not used anywhere as of r5957. + The position is a prediction of the vehicle's current position, based on + its last known position, the time elapsed since it was obtained and possibly + other factors. This would be used for positions obtained through inertial + navigation. **/ + attr_position_valid_valid, /**< The position is valid and can be used for all purposes. **/ }; #define ATTR_IS_INT(x) ((x) >= attr_type_int_begin && (x) <= attr_type_int_end) |