Tremolo slope

[Philippe Auclair]

Hi,

Is there a solution to have a slope in a full measure tremolo?
This doesn't seem to work.
Philippe Auclair

\version "2.20.0"
\score {
  \new Staff {
    \override StemTremolo  #'slope = #0.5
    \repeat tremolo 16 { c'32 c'' }
  }
}