Document the return value of choose() and how it is useful.

diff --git a/theme.rst b/theme.rst
index 2e70ca9db8004b9fe44d579d05e78818fea3c66e..7fbe735b1ce6f081947603c1f4c0386b217f1982 100644 (file)
--- a/theme.rst
+++ b/theme.rst
@@ -203,6 +203,9 @@ you must set it directly on the effect::
   input0_scaled:set_int("width", 1280)  -- Set on both alternatives.
   input0_scaled:set_int("height", 720)
 
+  -- This is also possible, as choose() returns the chosen effect:
+  input0_scaled:choose(ResampleEffect):set_float("zoom_y", 1.0001)
+
 Actually, more versions are created than you'd immediately expect.
 In particular, the output format for the live output and all previews are
 different (Y'CbCr versus RGBA), which is also handled transparently for you.