Moving: MVEIT (Part 7 of 9)

       Name: MVEIT (Part 7 of 9)                                     [Show more]
       Type: Subroutine
   Category: Moving
    Summary: Move current ship: Rotate ship's orientation vectors by pitch/roll
  Deep dive: Orientation vectors
             Pitching and rolling
    Context: See this subroutine in context in the source code
 References: No direct references to this subroutine in this source file


 This routine has multiple stages. This stage does the following:

   * Rotate the ship's orientation vectors according to our pitch and roll

 As with the previous step, this is all about moving the other ships rather
 than us (even though we are the one doing the moving). So we rotate the
 current ship's orientation vectors (which defines its orientation in space),
 by the angles we are "moving" the rest of the sky through (alpha and beta, our
 roll and pitch), so the ship appears to us to be stationary while we rotate.


 LDY #9                 ; Apply our pitch and roll rotations to the current
 JSR MVS4               ; ship's nosev vector

 LDY #15                ; Apply our pitch and roll rotations to the current
 JSR MVS4               ; ship's roofv vector

 LDY #21                ; Apply our pitch and roll rotations to the current
 JSR MVS4               ; ship's sidev vector