void Update()
{
// Spin the cube. Proves that the batch is reading the matrices just fine
var transforms = _brg.GetBatchMatrices(_batch);
transforms[0] = Matrix4x4.Rotate(Quaternion.Euler(Mathf.Sin(Time.time) * 180, Mathf.Sin(Time.time) * 180, Mathf.Cos(Time.time) * 180));
// I thought this would set the color in the shader but it isn't working for me
var instVals = _brg.GetBatchVectorArray(_batch, "_Color");
instVals[0] = new Vector4(0, 1, 0, 1);
}