added some convenience methods

src/any/difficulty/gradual.rs

@@ -8,7 +8,7 @@ use crate::{
     mania::{ManiaBeatmap, ManiaGradualDifficulty},
     osu::{OsuBeatmap, OsuGradualDifficulty},
     taiko::{TaikoBeatmap, TaikoGradualDifficulty},
-    Beatmap, Converted, ModeDifficulty,
+    Beatmap, ModeDifficulty,
 };
 
 /// Gradually calculate the difficulty attributes on maps of any mode.
@@ -48,10 +48,10 @@ pub enum GradualDifficulty {
 }
 
 macro_rules! from_converted {
-    ( $fn:ident, $mode:ident, $converted:ident, $gradual:ident ) => {
+    ( $fn:ident, $mode:ident, $converted:ident ) => {
         #[doc = concat!("Create a [`GradualDifficulty`] for a [`", stringify!($converted), "`]")]
         pub fn $fn(difficulty: &ModeDifficulty, converted: &$converted<'_>) -> Self {
-            Self::$mode($gradual::new(difficulty, converted))
+            Self::$mode(difficulty.gradual_difficulty(converted))
         }
     };
 }
@@ -62,29 +62,23 @@ impl GradualDifficulty {
         let map = Cow::Borrowed(map);
 
         match map.mode {
-            GameMode::Osu => Self::Osu(OsuGradualDifficulty::new(
-                difficulty,
-                &Converted::new(map, false),
-            )),
-            GameMode::Taiko => Self::Taiko(TaikoGradualDifficulty::new(
-                difficulty,
-                &Converted::new(map, false),
-            )),
-            GameMode::Catch => Self::Catch(CatchGradualDifficulty::new(
-                difficulty,
-                &Converted::new(map, false),
-            )),
-            GameMode::Mania => Self::Mania(ManiaGradualDifficulty::new(
-                difficulty,
-                &Converted::new(map, false),
-            )),
+            GameMode::Osu => Self::Osu(difficulty.gradual_difficulty(&OsuBeatmap::new(map, false))),
+            GameMode::Taiko => {
+                Self::Taiko(difficulty.gradual_difficulty(&TaikoBeatmap::new(map, false)))
+            }
+            GameMode::Catch => {
+                Self::Catch(difficulty.gradual_difficulty(&CatchBeatmap::new(map, false)))
+            }
+            GameMode::Mania => {
+                Self::Mania(difficulty.gradual_difficulty(&ManiaBeatmap::new(map, false)))
+            }
         }
     }
 
-    from_converted!(from_osu_map, Osu, OsuBeatmap, OsuGradualDifficulty);
-    from_converted!(from_taiko_map, Taiko, TaikoBeatmap, TaikoGradualDifficulty);
-    from_converted!(from_catch_map, Catch, CatchBeatmap, CatchGradualDifficulty);
-    from_converted!(from_mania_map, Mania, ManiaBeatmap, ManiaGradualDifficulty);
+    from_converted!(from_osu_map, Osu, OsuBeatmap);
+    from_converted!(from_taiko_map, Taiko, TaikoBeatmap);
+    from_converted!(from_catch_map, Catch, CatchBeatmap);
+    from_converted!(from_mania_map, Mania, ManiaBeatmap);
 }
 
 impl Iterator for GradualDifficulty {

src/any/difficulty/mode.rs

@@ -56,6 +56,19 @@ impl ModeDifficulty {
         M::strains(self, map)
     }
 
+    /// Create a gradual difficulty calculator for a [`Converted`] beatmap.
+    pub fn gradual_difficulty<M: IGameMode>(&self, map: &Converted<'_, M>) -> M::GradualDifficulty {
+        M::gradual_difficulty(self, map)
+    }
+
+    /// Create a gradual performance calculator for a [`Converted`] beatmap.
+    pub fn gradual_performance<M: IGameMode>(
+        &self,
+        map: &Converted<'_, M>,
+    ) -> M::GradualPerformance {
+        M::gradual_performance(self, map)
+    }
+
     pub(crate) const fn get_mods(&self) -> u32 {
         self.mods
     }

src/any/performance/gradual.rs

@@ -8,7 +8,7 @@ use crate::{
     mania::{ManiaBeatmap, ManiaGradualPerformance},
     osu::{OsuBeatmap, OsuGradualPerformance},
     taiko::{TaikoBeatmap, TaikoGradualPerformance},
-    Beatmap, Converted, ModeDifficulty,
+    Beatmap, ModeDifficulty,
 };
 
 /// Gradually calculate the performance attributes on maps of any mode.
@@ -97,10 +97,10 @@ pub enum GradualPerformance {
 }
 
 macro_rules! from_converted {
-    ( $fn:ident, $mode:ident, $converted:ident, $gradual:ident ) => {
+    ( $fn:ident, $mode:ident, $converted:ident ) => {
         #[doc = concat!("Create a [`GradualPerformance`] for a [`", stringify!($converted), "`]")]
         pub fn $fn(difficulty: &ModeDifficulty, converted: &$converted<'_>) -> Self {
-            Self::$mode($gradual::new(difficulty, converted))
+            Self::$mode(difficulty.gradual_performance(converted))
         }
     };
 }
@@ -111,29 +111,25 @@ impl GradualPerformance {
         let map = Cow::Borrowed(map);
 
         match map.mode {
-            GameMode::Osu => Self::Osu(OsuGradualPerformance::new(
-                difficulty,
-                &Converted::new(map, false),
-            )),
-            GameMode::Taiko => Self::Taiko(TaikoGradualPerformance::new(
-                difficulty,
-                &Converted::new(map, false),
-            )),
-            GameMode::Catch => Self::Catch(CatchGradualPerformance::new(
-                difficulty,
-                &Converted::new(map, false),
-            )),
-            GameMode::Mania => Self::Mania(ManiaGradualPerformance::new(
-                difficulty,
-                &Converted::new(map, false),
-            )),
+            GameMode::Osu => {
+                Self::Osu(difficulty.gradual_performance(&OsuBeatmap::new(map, false)))
+            }
+            GameMode::Taiko => {
+                Self::Taiko(difficulty.gradual_performance(&TaikoBeatmap::new(map, false)))
+            }
+            GameMode::Catch => {
+                Self::Catch(difficulty.gradual_performance(&CatchBeatmap::new(map, false)))
+            }
+            GameMode::Mania => {
+                Self::Mania(difficulty.gradual_performance(&ManiaBeatmap::new(map, false)))
+            }
         }
     }
 
-    from_converted!(from_osu_map, Osu, OsuBeatmap, OsuGradualPerformance);
-    from_converted!(from_taiko_map, Taiko, TaikoBeatmap, TaikoGradualPerformance);
-    from_converted!(from_catch_map, Catch, CatchBeatmap, CatchGradualPerformance);
-    from_converted!(from_mania_map, Mania, ManiaBeatmap, ManiaGradualPerformance);
+    from_converted!(from_osu_map, Osu, OsuBeatmap);
+    from_converted!(from_taiko_map, Taiko, TaikoBeatmap);
+    from_converted!(from_catch_map, Catch, CatchBeatmap);
+    from_converted!(from_mania_map, Mania, ManiaBeatmap);
 
     /// Process the next hit object and calculate the performance attributes
     /// for the resulting score state.

src/any/performance/mod.rs

@@ -288,25 +288,25 @@ impl<A: AttributeProvider> From<A> for Performance<'_> {
 }
 
 macro_rules! impl_from_converted {
-    ( $mode:ident: $performance:ident ) => {
+    ( $mode:ident ) => {
         impl<'a> From<Converted<'a, $mode>> for Performance<'a> {
             fn from(converted: Converted<'a, $mode>) -> Self {
-                Self::$mode($performance::new(converted))
+                Self::$mode(converted.into())
             }
         }
 
         impl<'a, 'b: 'a> From<&'b Converted<'a, $mode>> for Performance<'a> {
             fn from(converted: &'b Converted<'a, $mode>) -> Self {
-                Self::$mode($performance::new(converted.as_owned()))
+                Self::$mode(converted.as_owned().into())
             }
         }
     };
 }
 
-impl_from_converted!(Osu: OsuPerformance);
-impl_from_converted!(Taiko: TaikoPerformance);
-impl_from_converted!(Catch: CatchPerformance);
-impl_from_converted!(Mania: ManiaPerformance);
+impl_from_converted!(Osu);
+impl_from_converted!(Taiko);
+impl_from_converted!(Catch);
+impl_from_converted!(Mania);
 
 /// While generating remaining hitresults, decide how they should be distributed.
 #[derive(Copy, Clone, Debug, Default, Eq, PartialEq)]

src/catch/mod.rs

@@ -36,6 +36,9 @@ pub struct Catch;
 impl IGameMode for Catch {
     type DifficultyAttributes = CatchDifficultyAttributes;
     type Strains = CatchStrains;
+    type Performance<'map> = CatchPerformance<'map>;
+    type GradualDifficulty = CatchGradualDifficulty;
+    type GradualPerformance = CatchGradualPerformance;
 
     fn try_convert(map: &mut Cow<'_, Beatmap>) -> ConvertStatus {
         convert::try_convert(map)
@@ -51,4 +54,22 @@ impl IGameMode for Catch {
     fn strains(difficulty: &ModeDifficulty, converted: &CatchBeatmap<'_>) -> Self::Strains {
         strains::strains(difficulty, converted)
     }
+
+    fn performance(map: CatchBeatmap<'_>) -> Self::Performance<'_> {
+        CatchPerformance::new(map)
+    }
+
+    fn gradual_difficulty(
+        difficulty: &ModeDifficulty,
+        map: &CatchBeatmap<'_>,
+    ) -> Self::GradualDifficulty {
+        CatchGradualDifficulty::new(difficulty, map)
+    }
+
+    fn gradual_performance(
+        difficulty: &ModeDifficulty,
+        map: &CatchBeatmap<'_>,
+    ) -> Self::GradualPerformance {
+        CatchGradualPerformance::new(difficulty, map)
+    }
 }

src/mania/mod.rs

@@ -33,6 +33,9 @@ pub struct Mania;
 impl IGameMode for Mania {
     type DifficultyAttributes = ManiaDifficultyAttributes;
     type Strains = ManiaStrains;
+    type Performance<'map> = ManiaPerformance<'map>;
+    type GradualDifficulty = ManiaGradualDifficulty;
+    type GradualPerformance = ManiaGradualPerformance;
 
     fn try_convert(map: &mut Cow<'_, Beatmap>) -> ConvertStatus {
         convert::try_convert(map)
@@ -48,4 +51,22 @@ impl IGameMode for Mania {
     fn strains(difficulty: &ModeDifficulty, converted: &ManiaBeatmap<'_>) -> Self::Strains {
         strains::strains(difficulty, converted)
     }
+
+    fn performance(map: ManiaBeatmap<'_>) -> Self::Performance<'_> {
+        ManiaPerformance::new(map)
+    }
+
+    fn gradual_difficulty(
+        difficulty: &ModeDifficulty,
+        map: &ManiaBeatmap<'_>,
+    ) -> Self::GradualDifficulty {
+        ManiaGradualDifficulty::new(difficulty, map)
+    }
+
+    fn gradual_performance(
+        difficulty: &ModeDifficulty,
+        map: &ManiaBeatmap<'_>,
+    ) -> Self::GradualPerformance {
+        ManiaGradualPerformance::new(difficulty, map)
+    }
 }

src/model/beatmap/converted.rs

@@ -5,7 +5,10 @@ use std::{
     marker::PhantomData,
 };
 
-use crate::model::mode::{ConvertStatus, IGameMode};
+use crate::{
+    model::mode::{ConvertStatus, IGameMode},
+    ModeDifficulty,
+};
 
 use super::{attributes::BeatmapAttributesBuilder, Beatmap};
 
@@ -43,6 +46,24 @@ impl<'a, M> Converted<'a, M> {
     }
 }
 
+impl<M> Converted<'_, M> {
+    /// Sum up the duration of all breaks (in milliseconds).
+    pub fn total_break_time(&self) -> f64 {
+        self.map.total_break_time()
+    }
+
+    /// Returns a [`BeatmapAttributesBuilder`] to calculate modified beatmap
+    /// attributes.
+    pub fn attributes(&self) -> BeatmapAttributesBuilder {
+        self.into()
+    }
+
+    /// The beats per minute of the map.
+    pub fn bpm(&self) -> f64 {
+        self.map.bpm()
+    }
+}
+
 impl<M: IGameMode> Converted<'_, M> {
     /// Attempt to convert a [`Beatmap`] to the specified mode.
     ///
@@ -72,20 +93,14 @@ impl<M: IGameMode> Converted<'_, M> {
         Self::try_from_owned(map).unwrap_or_else(|_| panic!("{}", INCOMPATIBLE_MODES))
     }
 
-    /// Sum up the duration of all breaks (in milliseconds).
-    pub fn total_break_time(&self) -> f64 {
-        self.map.total_break_time()
+    /// Create a gradual difficulty calculator for the map.
+    pub fn gradual_difficulty(&self, difficulty: &ModeDifficulty) -> M::GradualDifficulty {
+        difficulty.gradual_difficulty(self)
     }
 
-    /// Returns a [`BeatmapAttributesBuilder`] to calculate modified beatmap
-    /// attributes.
-    pub fn attributes(&self) -> BeatmapAttributesBuilder {
-        self.into()
-    }
-
-    /// The beats per minute of the map.
-    pub fn bpm(&self) -> f64 {
-        self.map.bpm()
+    /// Create a gradual performance calculator for the map.
+    pub fn gradual_performance(&self, difficulty: &ModeDifficulty) -> M::GradualPerformance {
+        difficulty.gradual_performance(self)
     }
 }
 
@@ -93,13 +108,18 @@ impl<'a, M: IGameMode> Converted<'a, M> {
     /// Borrow the contained [`Beatmap`] to cheaply create a new owned
     /// [`Converted`].
     ///
-    /// This is the same as `.clone()` except cheap but its lifetime might be
+    /// This is the same as `.clone()` except cheap - but its lifetime might be
     /// shorter.
     #[must_use]
     pub fn as_owned(&'a self) -> Self {
         Self::new(Cow::Borrowed(self.map.as_ref()), self.is_convert)
     }
 
+    /// Create a performance calculator for the map.
+    pub fn performance(self) -> M::Performance<'a> {
+        M::performance(self)
+    }
+
     /// Attempt to convert a [`&Beatmap`] to the specified mode.
     ///
     /// If the conversion is incompatible, `None` is returned.

src/model/beatmap/mod.rs

@@ -5,7 +5,7 @@ use rosu_map::{
     LATEST_FORMAT_VERSION,
 };
 
-use crate::{Difficulty, Performance};
+use crate::{Difficulty, GradualDifficulty, GradualPerformance, ModeDifficulty, Performance};
 
 pub use self::{
     attributes::{BeatmapAttributes, BeatmapAttributesBuilder, HitWindows},
@@ -70,16 +70,26 @@ impl Beatmap {
         rosu_map::from_bytes(bytes)
     }
 
-    /// Create a new difficulty calculator for this [`Beatmap`].
+    /// Create a difficulty calculator for this [`Beatmap`].
     pub fn difficulty(&self) -> Difficulty<'_> {
         Difficulty::new(self)
     }
 
-    /// Create a new performance calculator for this [`Beatmap`].
+    /// Create a performance calculator for this [`Beatmap`].
     pub fn performance(&self) -> Performance<'_> {
         Performance::new(self)
     }
 
+    /// Create a gradual difficulty calculator for this [`Beatmap`].
+    pub fn gradual_difficulty(&self, difficulty: &ModeDifficulty) -> GradualDifficulty {
+        GradualDifficulty::new(difficulty, self)
+    }
+
+    /// Create a gradual performance calculator for this [`Beatmap`].
+    pub fn gradual_performance(&self, difficulty: &ModeDifficulty) -> GradualPerformance {
+        GradualPerformance::new(difficulty, self)
+    }
+
     /// Finds the [`TimingPoint`] that is active at the given time.
     pub(crate) fn timing_point_at(&self, time: f64) -> Option<&TimingPoint> {
         timing_point_at(&self.timing_points, time)

src/model/mode.rs

@@ -22,6 +22,15 @@ pub trait IGameMode: Sized {
     /// The resulting type of a strain calculation.
     type Strains;
 
+    /// The type of a performance calculator.
+    type Performance<'map>;
+
+    /// The type of a gradual difficulty calculator.
+    type GradualDifficulty;
+
+    /// The type of a gradual performance calculator.
+    type GradualPerformance;
+
     /// Attempt to convert a beatmap.
     ///
     /// In case [`ConvertStatus::Incompatible`] is returned, the map should
@@ -38,6 +47,21 @@ pub trait IGameMode: Sized {
     /// Perform a difficulty calculation for a [`Converted`] beatmap without
     /// processing the final skill values.
     fn strains(difficulty: &ModeDifficulty, map: &Converted<'_, Self>) -> Self::Strains;
+
+    /// Create a performance calculator for a [`Converted`] beatmap.
+    fn performance(map: Converted<'_, Self>) -> Self::Performance<'_>;
+
+    /// Create a gradual difficulty calculator for a [`Converted`] beatmap.
+    fn gradual_difficulty(
+        difficulty: &ModeDifficulty,
+        map: &Converted<'_, Self>,
+    ) -> Self::GradualDifficulty;
+
+    /// Create a gradual performance calculator for a [`Converted`] beatmap.
+    fn gradual_performance(
+        difficulty: &ModeDifficulty,
+        map: &Converted<'_, Self>,
+    ) -> Self::GradualPerformance;
 }
 
 /// The status of a conversion through [`IGameMode::try_convert`].

src/osu/mod.rs

@@ -37,6 +37,9 @@ pub struct Osu;
 impl IGameMode for Osu {
     type DifficultyAttributes = OsuDifficultyAttributes;
     type Strains = OsuStrains;
+    type Performance<'map> = OsuPerformance<'map>;
+    type GradualDifficulty = OsuGradualDifficulty;
+    type GradualPerformance = OsuGradualPerformance;
 
     fn try_convert(map: &mut Cow<'_, Beatmap>) -> ConvertStatus {
         convert::try_convert(map)
@@ -52,4 +55,22 @@ impl IGameMode for Osu {
     fn strains(difficulty: &ModeDifficulty, converted: &OsuBeatmap<'_>) -> Self::Strains {
         strains::strains(difficulty, converted)
     }
+
+    fn performance(map: OsuBeatmap<'_>) -> Self::Performance<'_> {
+        OsuPerformance::new(map)
+    }
+
+    fn gradual_difficulty(
+        difficulty: &ModeDifficulty,
+        map: &OsuBeatmap<'_>,
+    ) -> Self::GradualDifficulty {
+        OsuGradualDifficulty::new(difficulty, map)
+    }
+
+    fn gradual_performance(
+        difficulty: &ModeDifficulty,
+        map: &OsuBeatmap<'_>,
+    ) -> Self::GradualPerformance {
+        OsuGradualPerformance::new(difficulty, map)
+    }
 }

src/taiko/mod.rs

@@ -33,6 +33,9 @@ pub struct Taiko;
 impl IGameMode for Taiko {
     type DifficultyAttributes = TaikoDifficultyAttributes;
     type Strains = TaikoStrains;
+    type Performance<'map> = TaikoPerformance<'map>;
+    type GradualDifficulty = TaikoGradualDifficulty;
+    type GradualPerformance = TaikoGradualPerformance;
 
     fn try_convert(map: &mut Cow<'_, Beatmap>) -> ConvertStatus {
         convert::try_convert(map)
@@ -48,4 +51,22 @@ impl IGameMode for Taiko {
     fn strains(difficulty: &ModeDifficulty, converted: &TaikoBeatmap<'_>) -> Self::Strains {
         strains::strains(difficulty, converted)
     }
+
+    fn performance(map: TaikoBeatmap<'_>) -> Self::Performance<'_> {
+        TaikoPerformance::new(map)
+    }
+
+    fn gradual_difficulty(
+        difficulty: &ModeDifficulty,
+        map: &TaikoBeatmap<'_>,
+    ) -> Self::GradualDifficulty {
+        TaikoGradualDifficulty::new(difficulty, map)
+    }
+
+    fn gradual_performance(
+        difficulty: &ModeDifficulty,
+        map: &TaikoBeatmap<'_>,
+    ) -> Self::GradualPerformance {
+        TaikoGradualPerformance::new(difficulty, map)
+    }
 }