add show example and scanner pattern

src/patterns.rs

@@ -1,13 +1,32 @@
+use serde_derive::{Deserialize, Serialize};
+use std::cmp::{max, min, Ordering};
+use std::convert::Infallible;
 use std::fmt;
+use std::ops::Div;
 
-pub(crate) enum patterns<const N: usize> {
+#[derive(Serialize, Deserialize, Debug)]
+#[serde(tag = "type")]
+pub(crate) enum Patterns<const N: usize> {
     Rainbow(Rainbow<N>),
     Fade(Fade<N>),
     ColorWipe(ColorWipe<N>),
     Scanner(Scanner<N>),
 }
 
-#[derive(Clone, Copy, Debug, Default)]
+impl<const N: usize> Iterator for Patterns<N> {
+    type Item = Strip<N>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        match self {
+            Patterns::Rainbow(p) => p.next(),
+            Patterns::Fade(p) => p.next(),
+            Patterns::ColorWipe(p) => p.next(),
+            Patterns::Scanner(p) => p.next(),
+        }
+    }
+}
+
+#[derive(Clone, Copy, Debug, Default, Serialize, Deserialize)]
 pub struct PixelColor {
     pub(crate) red: u8,
     pub(crate) green: u8,
@@ -26,6 +45,18 @@ impl fmt::Display for PixelColor {
     }
 }
 
+impl Div<u8> for PixelColor {
+    type Output = PixelColor;
+
+    fn div(self, rhs: u8) -> Self::Output {
+        PixelColor {
+            red: self.red / rhs,
+            green: self.green / rhs,
+            blue: self.blue / rhs,
+        }
+    }
+}
+
 #[derive(Copy, Clone)]
 pub struct Strip<const N: usize> {
     pub strip: [PixelColor; N],
@@ -197,3 +228,43 @@ impl<const N: usize> Iterator for Fade<N> {
         Some(strip)
     }
 }
+
+//////////////////////////////////////////////////////////////////////////
+/// scanner pattern ////////////////////////////////////////////////////
+//////////////////////////////////////////////////////////////////////////
+
+#[derive(Serialize, Deserialize, Debug)]
+pub struct Scanner<const N: usize> {
+    pub(crate) current_iteration: usize,
+    pub(crate) color: PixelColor,
+    pub(crate) background_color: Option<PixelColor>,
+}
+
+impl<const N: usize> Iterator for Scanner<N> {
+    type Item = Strip<N>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        let mut strip = Strip::<N>::default();
+        if let Some(c) = self.background_color {
+            strip.fill(c);
+        } else {
+            strip.fill(PixelColor::default());
+        }
+
+        let current_led = self.current_iteration % N;
+        let min_led;
+        if current_led < 8 {
+            min_led = 0;
+        } else {
+            min_led = current_led - 8;
+        }
+        let mut c = self.color;
+        for i in min_led..current_led {
+            strip.strip[i] = c;
+            c = c / 2;
+            println!("{}", c);
+        }
+        self.current_iteration += 1;
+        Some(strip)
+    }
+}