Add woot precision (#10)

* woot precision

* update formula

* increase exponent

* overhaul

* adjustments

* more adjust

* yeah

* changes

* 3

src/osu_2019/pp.rs

@@ -400,6 +400,11 @@ impl<'m> OsuPP<'m> {
             aim_value *= base_buff;
         }
 
+        // Precision buff (reading)
+        if attributes.cs > 5.58 {
+            aim_value *= ((attributes.cs as f32 - 5.46).powf(1.8) + 1.0).powf(0.03);
+        }
+
         // Scale with accuracy
         aim_value *= 0.3 + self.acc.unwrap() / 2.0;
         aim_value *= 0.98 + attributes.od as f32 * attributes.od as f32 / 2500.0;

src/osu_2019/stars.rs

@@ -28,6 +28,7 @@ pub fn stars(map: &Beatmap, mods: u32, passed_objects: Option<usize>) -> OsuDiff
     let mut diff_attributes = OsuDifficultyAttributes {
         ar: map_attributes.ar,
         od: map_attributes.od,
+        cs: map_attributes.cs,
         ..Default::default()
     };
 
@@ -39,8 +40,8 @@ pub fn stars(map: &Beatmap, mods: u32, passed_objects: Option<usize>) -> OsuDiff
     let radius = OBJECT_RADIUS * (1.0 - 0.7 * (map_attributes.cs as f32 - 5.0) / 5.0) / 2.0;
     let mut scaling_factor = NORMALIZED_RADIUS / radius;
 
-    if radius < 30.0 {
-        let small_circle_bonus = (30.0 - radius).min(5.0) / 50.0;
+    if radius < 30.05 {
+        let small_circle_bonus = ((30.05 - radius) / 50.0).powf(1.1) * 1.45;
         scaling_factor *= 1.0 + small_circle_bonus;
     }
 
@@ -148,6 +149,7 @@ pub struct OsuDifficultyAttributes {
     pub ar: f64,
     pub od: f64,
     pub hp: f64,
+    pub cs: f64,
     pub n_circles: usize,
     pub n_sliders: usize,
     pub n_spinners: usize,