27: Moving with gaze

================================================================================

Today’s hack is more an aside while I’m focussing on yet another Tevris rewrite.

I thought I’d play with an idea for controlling the left/right movement of the
active piece based on where you’re looking.

Now, knowing where you’re looking in 3D space is both a hard thing to Google,
and a hard thing to explain. So take this solution with a grain of salt:

var getpos = function (obj) {
  camera.matrixWorldInverse.getInverse( camera.matrixWorld );
var mat = new
THREE.Matrix4().multiplyMatrices( camera.matrixWorldInverse, obj.matrixWorld );
  var pos = obj.position.clone().applyProjection(mat);
  return pos;
};
var getLooking = function () {
  var pos = getpos(board[0][Math.floor(cols/2)]);
  // MAGIC 💩
  if (pos.x - pos.z > 180) {
    return 'left';
  }
  if (pos.x - pos.z < 120) {
    return 'right';
  }
};

There’s a lot going on there, and some MAGIC, and it’s not going to scale, but
it sort of works.

[IMAGE: https://blog.omgmog.net/images/2016-10/27/giphy.gif]

I’m not completely happy with this, so you may have noticed the poop emoji (💩)
all over the place. I’ll definitely throw this away with the re-write I’m
working on, but it’s nice to explore the idea.

================================================================================
Published October 27, 2016

Generated from the original post:
https://blog.omgmog.net/cardboctober/cardboctober-27/


Max Glenister is an interface designer and senior full-stack developer from
Oxfordshire. He writes mostly about front-end development and technology.

- Mastodon: https://indieweb.social/@omgmog
- Github: https://github.com/omgmog
- Reddit: https://reddit.com/u/omgmog
- Discord: https://discordapp.com/users/omgmog#6206