marble shadow on the ground

[jeromeetienne]

• when the marble is flying, the shaddow is still close to it
• this is super unrealistice

  solution

• at each .update(), detect the X,Z on the map
• get the marble position
• detect the closest voxel below
• set the shadow y accordingly

[jeromeetienne]

done in f4082634b78265a376ef7bba10e568ce4011d96d