Fix typo in visual shaders regarding switch node

Clarified that the last sentence is an
instruction, and rectified the state of the
components necessary to provide the output as
true

tutorials/shaders/visual_shaders.rst

@@ -224,7 +224,7 @@ Switch node
 ~~~~~~~~~~~
 
 The ``Switch`` node returns a vector if the boolean condition is ``true`` or
-``false``. ``Boolean`` was introduced above. If you convert a vector to a true
-boolean, all components of the vector should be above zero.
+``false``. ``Boolean`` was introduced above. If you want to convert a vector
+to a true boolean, all components of the vector should be non-zero.
 
 .. image:: img/vs_switch.webp