diff options
Diffstat (limited to 'src/roadveh.h')
| -rw-r--r-- | src/roadveh.h | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/src/roadveh.h b/src/roadveh.h index c73575a13..e49badbec 100644 --- a/src/roadveh.h +++ b/src/roadveh.h @@ -262,6 +262,36 @@ protected: // These functions should not be called outside acceleration code. return trackbits == TRACK_BIT_X || trackbits == TRACK_BIT_Y; } + + /** + * Road vehicles have to use GetSlopeZ() to compute their height + * if they are reversing because in that case, their direction + * is not parallel with the road. It is safe to return \c true + * even if it is not reversing. + * @return are we (possibly) reversing? + */ + FORCEINLINE bool HasToUseGetSlopeZ() + { + const RoadVehicle *rv = this->First(); + + /* Check if this vehicle is in the same direction as the road under. + * We already know it has either GVF_GOINGUP_BIT or GVF_GOINGDOWN_BIT set. */ + + if (rv->state <= RVSB_TRACKDIR_MASK && IsReversingRoadTrackdir((Trackdir)rv->state)) { + /* If the first vehicle is reversing, this vehicle may be reversing too + * (especially if this is the first, and maybe the only, vehicle).*/ + return true; + } + + while (rv != this) { + /* If any previous vehicle has different direction, + * we may be in the middle of reversing. */ + if (this->direction != rv->direction) return true; + rv = rv->Next(); + } + + return false; + } }; #define FOR_ALL_ROADVEHICLES(var) FOR_ALL_VEHICLES_OF_TYPE(RoadVehicle, var) |