Track geometry: UpdateCurveVector

       Name: UpdateCurveVector                                       [Show more]
       Type: Subroutine
   Category: Track geometry
    Summary: Move to the next segment vector along in the direction we are
             facing, but only for curved track sections
  Deep dive: Building a 3D track from sections and segments
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * GetTrackSegment (Part 3 of 3) calls UpdateCurveVector
             * TurnPlayerAround calls UpdateCurveVector


.UpdateCurveVector

 LDA thisSectionFlags   \ If bit 0 of the track section's flag byte is clear,
 AND #1                 \ then this is a straight track section, so return from
 BEQ ChangeDirection-1  \ the subroutine (as ChangeDirection-1 contains an RTS)

                        \ Otherwise this is a curved track section, so fall
                        \ through into UpdateVectorNumber to update the value
                        \ of thisVectorNumber to the number of the next vector
                        \ along the track