optionally clear after each fade step

2 files changed, 27 insertions, 6 deletions

diff --git a/src/lib.rs b/src/lib.rs
index 5952517..fd2d4f2 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -839,19 +839,26 @@ pub struct Fade
     to:       Palette,
     hz:       u8,
     duration: Duration,
+    clear:    bool,
 }
 
 impl Fade
 {
-    pub fn new(from: Palette, to: Palette, duration: Duration, hz: u8) -> Self
+    pub fn new(
+        from: Palette,
+        to: Palette,
+        duration: Duration,
+        hz: u8,
+        clear: bool,
+    ) -> Self
     {
         let hz = if hz == 0 { 1 } else { hz };
-        Self { from, to, hz, duration }
+        Self { from, to, hz, duration, clear }
     }
 
     pub fn commence(self, con: &Console) -> io::Result<()>
     {
-        let Self { from, to, hz, duration } = self;
+        let Self { from, to, hz, duration, clear } = self;
         con.apply_palette(&from)?;
 
         let fade = FadePalette::from(&con.current_palette()?);
@@ -866,6 +873,9 @@ impl Fade
             let progress = f64::from(i) / f64::from(iters);
             let pal = Palette::from(&fade.towards(&fade_to, progress));
             con.apply_palette(&pal)?;
+            if clear {
+                con.clear()?;
+            }
             let next = i * tick;
             std::thread::sleep(next.saturating_sub(t_0.elapsed()));
         }
diff --git a/src/vtcol.rs b/src/vtcol.rs
index 3694753..e3ab5f2 100644
--- a/src/vtcol.rs
+++ b/src/vtcol.rs
@@ -34,7 +34,7 @@ enum Job
     /** Toggle between two schemes. */
     Toggle(Scheme, Scheme),
     /** Fade from current scheme to another. */
-    Fade(Option<Scheme>, Scheme, Duration, u8),
+    Fade(Option<Scheme>, Scheme, Duration, u8, bool),
 }
 
 impl<'a> Job
@@ -126,6 +126,13 @@ impl<'a> Job
                             .takes_value(true),
                     )
                     .arg(
+                        Arg::with_name("clear")
+                            .short("c")
+                            .long("clear")
+                            .help("clear terminal on each fade step")
+                            .takes_value(false),
+                    )
+                    .arg(
                         Arg::with_name("frequency")
                             .value_name("HZ")
                             .short("h")
@@ -202,6 +209,7 @@ impl<'a> Job
                 } else {
                     DEFAULT_FADE_UPDATE_HZ
                 };
+                let clear = subm.is_present("clear");
                 let dur = Duration::from_millis(dur);
 
                 match (subm.value_of("from"), subm.value_of("to")) {
@@ -213,6 +221,7 @@ impl<'a> Job
                             Scheme::from(to),
                             dur,
                             hz,
+                            clear,
                         )),
                 }
             },
@@ -280,7 +289,8 @@ impl<'a> Job
             Self::Set(scm) => Self::set_scheme(scm)?,
             Self::Get => Self::get_scheme()?,
             Self::Toggle(one, two) => Self::toggle_scheme(one, two)?,
-            Self::Fade(from, to, ms, hz) => Self::fade(from, to, ms, hz)?,
+            Self::Fade(from, to, ms, hz, clear) =>
+                Self::fade(from, to, ms, hz, clear)?,
         }
 
         Ok(())
@@ -335,6 +345,7 @@ impl<'a> Job
         to: Scheme,
         dur: Duration,
         hz: u8,
+        clear: bool,
     ) -> Result<()>
     {
         let fd = Console::current()?;
@@ -347,7 +358,7 @@ impl<'a> Job
         };
         let to = Palette::try_from(&to)?;
 
-        let fade = Fade::new(from, to, dur, hz);
+        let fade = Fade::new(from, to, dur, hz, clear);
 
         fade.commence(&fd)?;
         Ok(())