fix(random): pass dtype argument to numpy random Generator

numpy random Generator methods do not check the datatype of an output
array, so if the output dtype is not the default (np.float64), the
dtype must be explicitly passed to the generator.

Closes #288

draco/util/random.py

@@ -418,11 +418,16 @@ def _call(*args, **kwargs):
             # A worker method for each thread to fill its part of the array with the
             # random numbers
             def _fill(gen: np.random.Generator, local_array: np.ndarray) -> None:
+                if has_dtype:
+                    kwargs["dtype"] = dtype
                 if has_out:
+                    if out.dtype != dtype:
+                        raise TypeError(
+                            f"Output array of type f{local_array.dtype} does not "
+                            f"match dtype argument {dtype}."
+                        )
                     method(gen, *args, **kwargs, out=local_array)
                 else:
-                    if has_dtype:
-                        kwargs["dtype"] = dtype
                     local_array[:] = method(
                         gen,
                         *args,