Add Grid-Aligned behavior to Playlab

[Hamms]

For our BB-8 levels; this is primarily to fix the behavior where BB-8 turns to face the null direction (south) between each movement step:

Behavior that is particularly funky when the solution involves using relative movement:

To fix this, I added dedicated methods for turning BB-8 (and animating the turn) so that we can highlight and animate the block, and added a new behavior which we can apply when using these blocks so that BB-8 can avoid being faced south and being compelled to move, resulting in an animation that looks like this:

[Hamms]

I'd love to solicit some opinions on whether or not this is the correct place to set this behavior

[islemaster]

This seems good to me. It's actually weirder that I don't see a corresponding setActivity call in the else case.

[Hamms]

I think it's the case that the else case expects BEHAVIOR_STOP, which is the default. If I'm correct then I could add that corresponding call for cleanliness, but if I'm not I have no idea what all could break

[islemaster]

Very nice!

[islemaster]

Style nit: You could check this condition and throw as an early-out at the top of this method, which would make it more obvious that the rest of the method is a simple command list with no branches.

Studio.turnSingle = function (opts) {
  if (!skin.gridAlignedMovement) {
    throw new TypeError("Studio.turnSingle is only valid in grid-aligned mode");
  }

  const sprite = Studio.sprite[opts.spriteIndex];
  sprite.lastMove = Studio.tickCount;
  sprite.setActivity(constants.BEHAVIOR_GRID_ALIGNED);
  sprite.addAction(new GridTurn(opts.dir, skin.slowExecutionFactor));
  Studio.yieldGridAlignedTicks();
  Studio.lastMoveSingleDir = opts.dir;
};

[islemaster]

This seems good to me. It's actually weirder that I don't see a corresponding setActivity call in the else case.

[islemaster]

Unnecessary nested describe blocks?

[Hamms]

sort of unnecessary, but it is the case that update can have some pretty different behavior based on when in the "lifecycle" of destination determination it's called, and I wanted to make absolutely clear which case we're in