Starting to support arrays and tuples for inout

oxydsp-dsp/src/units.rs

@@ -0,0 +1,38 @@
+use std::f64::consts::PI;
+
+use crate::map;
+
+// Represents digital frequency
+#[derive(Clone, Copy, PartialEq, PartialOrd)]
+pub struct DigitalFrequency(pub usize);
+
+#[derive(Clone, Copy, PartialEq, PartialOrd)]
+pub struct Phase(pub DigitalFrequency);
+
+impl DigitalFrequency
+{
+    pub fn from_rad(radians_per_sample: f64) -> Self
+    {
+        // Frequnecy wraps arround : Going at 2 pi radians per second
+        // Is like not oscillating at all
+        let f = radians_per_sample.rem_euclid(radians_per_sample);
+
+        // Then we map the [0, 2*PI] range into the 0 to usize range
+        DigitalFrequency(map(f, 0., 2. * PI, 0., usize::MAX as f64).floor() as usize)
+    }
+
+    pub fn from_time_frequency(hertz: f64, sample_rate: f64) -> Self
+    {
+        Self::from_rad(map(hertz, 0., sample_rate, 0., 2. * PI))
+    }
+
+    pub fn as_rad(&self) -> f64
+    {
+        map(self.0 as f64, 0., usize::MAX as f64, 0., 2. * PI)
+    }
+
+    pub fn as_time_frequency(&self, sample_rate: f64) -> f64
+    {
+        map(self.0 as f64, 0., usize::MAX as f64, 0., sample_rate)
+    }
+}