Slowly defining the BMS header elements

Cargo.lock

@@ -2518,6 +2518,17 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "katexit"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ccfb0b7ce7938f84a5ecbdca5d0a991e46bc9d6d078934ad5e92c5270fe547db"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "khronos-egl"
 version = "6.0.0"
@@ -3235,6 +3246,7 @@ dependencies = [
 name = "parser"
 version = "0.1.0"
 dependencies = [
+ "katexit",
  "strum 0.27.1",
  "strum_macros 0.27.1",
  "winnow",

Cargo.toml

@@ -1,4 +1,4 @@
 
 [workspace]
-resolver = "3"
+resolver = "2"
 members = [ "parser","player"]

parser/Cargo.toml

@@ -4,6 +4,7 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
+katexit = "0.1.5"
 strum = "0.27.1"
 strum_macros = "0.27.1"
 winnow = "0.7.11"

parser/src/header.rs

@@ -1,11 +1,13 @@
-struct Header {
+use strum_macros::FromRepr;
+
+pub struct Header {
     player: Player,
 }
 
-/// Defines the play side.
+/// `#PLAYER [1-4]`. Defines the play side.
 #[derive(FromRepr, Debug, PartialEq, Clone)]
 #[repr(u8)]
-enum Player {
+pub enum Player {
     One,   // SP
     Two,   // Couple play
     Three, // DP
@@ -17,3 +19,256 @@ impl Default for Player {
         Self::One
     }
 }
+
+/// `#RANK [0-3]`. Defines the judge difficulty.
+///
+/// We follow LR2 convention here, so Rank is 0,1,2,3
+pub enum Rank {
+    VeryHard, // RANK 0, +-8ms
+    Hard,     // RANK 1, +- 15ms
+    Normal,   // RANK 2, +- 18ms
+    Easy,     // RANK 3, +- 21ms
+}
+
+// LR2 Convention is to apply Normal when unspecified.
+impl Default for Rank {
+    fn default() -> Self {
+        Self::Normal
+    }
+}
+
+pub enum JudgeRankType {
+    /// `#RANK [0-3]` Normal rank system.
+    ///
+    /// This is what you see 99% of the time.
+    Rank,
+
+    /// `#DEFEXRANK n`. Percentage judge.
+    /// Defexrank is very strange. It specifies judge difficulty as a percentage of RANK 2.
+    /// This means that 100 is equal to RANK 2. If a DefExRank of 199.97 is sepcified then
+    /// the rank is 199.97% of RANK 2.
+    ///
+    /// TODO: Implement Defexrank
+    Defexrank(f32),
+    /// `#EXRANK[01-ZZ] n`. In-chart adjustable rank.
+    /// Exrank is also weird. It allows the timing window of the chart to be changed
+    /// during play.
+    ///
+    /// To steal from hitkey as an example.
+    /// ```
+    /// #RANK 2
+    /// #EXRANKaa 48
+    /// #EXRANKcc 100
+    /// #114a0:aa0000cc
+    /// ```
+    /// Would result in the timing window for measure 114 changing to DEFEXRANK 48,
+    /// and then going back to DEFEXRANK 100 at the end of the measure.
+    ///
+    /// The string represents the identifier (In the example "cc" or "aa")
+    /// and the f32 represents the rank as a percentage of rank 2.
+    Exrank(String, f32),
+}
+
+#[cfg_attr(doc, katexit::katexit)]
+/// `#TOTAL n`. Rate of Gague Recovery ™
+///
+/// Total is a bit tricky to wrap your head around.
+/// As far as the player is concerned, TOTAL is what defines the rate of gauge recovery.
+///
+/// Let n be the value of #TOTAL n, and y the total amount of objects in the chart
+/// the rate of gauge recovery on a PGREAT is
+/// $\frac{n}{y}$
+///
+/// If there are 400 objects to hit, and TOTAL is 200, we get $\frac{200}{400} = 0.5$
+///
+/// If this field is omitted, the spec does not specify what the default value should be.
+/// - LR2 uses 160
+/// - jbmsparser for beatoraja uses 100.
+/// - We will use 160
+pub struct Total(f64);
+
+impl Default for Total {
+    fn default() -> Total {
+        Self(160.0)
+    }
+}
+
+/// `#VOLWAV n`. Flat volume multiplier.
+///
+/// Defaults to 100.
+///
+/// In general, this gets ignored.
+///
+/// #VOLWAV 250 would be playing at 250% volume.
+///
+/// #VOLWAV 25 would be playing at 25% volume.
+pub struct Volwav(i32);
+
+/// `#STAGEFILE imagefilename`. Splash screen.
+///
+/// This command is omissible. When omitted it is expected that the default splashscreen
+/// will be used.
+pub struct Stagefile(String);
+
+/// `#BANNER imagefilename`. Song select banner image.
+pub struct Banner(String);
+
+/// `#BACKBMP imagefilename`. Static "movie" background.
+///
+/// If we chose to follow the OverActive style, then this is a pre-movie splash
+/// like the song title, genre and such in IIDX.
+/// https://right-stick.sub.jp/backbmp/index.html
+pub struct BackBmp(String);
+
+/// `#PLAYLEVEL n`. Song difficulty.
+///
+/// Reported difficulty level. This will usually be [1-12] IIDX style.
+///
+/// #PLAYLEVEL 0 is a strange case. This is usually for gimmick charts which
+/// use commands like `#RANDOM` or `#SWITCH`
+pub struct PlayLevel(u16);
+
+/// For whatever reason, BM98 used #PLAYLEVEL 3 as it's default if this was
+/// omitted. Apparently many followed this, even through it's not spec.
+impl Default for PlayLevel {
+    fn default() -> Self {
+        PlayLevel(3)
+    }
+}
+
+/// `#DIFFICULTY [1-5]`. Difficulty. Normal/Hyper etc
+///
+/// We follow an adjusted IIDX naming convention in this enum.
+/// Beginner, Normal, Hyper, Another are from IIDX, but we take INSANE from bms.
+/// There's a lot of naiming conventions, these are disambiguated in code comments
+///
+/// This command is omissable, and anything which doesn't have it is expected to be
+/// unsortable and unfilterable by this metric.
+#[derive(FromRepr, Debug, PartialEq, Clone)]
+#[repr(u8)]
+enum Difficulty {
+    Beginner, // Easy/Beginner/Light
+    Normal,   // Normal/Standard
+    Hyper,    // Hard
+    Another,  // EX, Maximum
+    Insane,   // Kusofumen, 糞譜面, INSANE, 発狂, hakkyou, SUPER-CRAZY
+}
+
+/// `#TITLE string` Title of the track.
+///
+/// Unsurprisingly, defines the title of the track.
+///
+/// When omitted, it's not actually defined what will happen.
+///
+/// There's no limit on the length of the title.
+///
+/// LR2 trims whitespace on the left and right of the title.
+///
+/// Encoding and decoding can be hellish, because of how old BMS as a format is.
+/// Don't expect UTF-8 everywhere, expect a good chunk of UTF-16, SHIFT-JIS,
+/// IEC 2022 and even EUC.
+///
+/// Implicit Subtitles exist as a form of in-band signalling.
+/// The subtitle is delimited by any of the following
+/// - `#TITLE main-sub-`
+/// - `#TITLE main～sub～`
+/// - `#TITLE main(sub)`
+/// - `#TITLE main[sub]`
+/// - `#TITLE main<sub>`
+/// - `#TITLE main␣␣sub` (Two+ halfwidth spaces)
+/// - `#TITLE main"sub"` (Straight double quotes)
+///
+/// Because of how varied these are, we will make a choice as to which we will support.
+/// This is fine since there's now a `#SUBTITLE` command.
+///
+/// We will support full width tilde and quote marks only.
+pub struct Title(String);
+
+/// `#SUBTITLE string` Subtitle of the track
+///
+/// Due to the limitations of the implicit subtitle, an actual SUBTITLE field was
+/// defined.
+///
+/// Omissible. LR2 will only check for a implicit subtitle if `#SUBTITLE` doesn't exist.
+pub struct Subtitle(String);
+
+/// `#ARTIST string`
+///
+/// Definition of the track artist. Interestingly Artist isn't actually defined
+/// in the spec.
+pub struct Artist(String);
+
+/// `#SUBARTIST string`
+///
+/// Added by LR2. This is used usually to define things like BGA artists,
+/// noters and other such co-artists.
+pub struct Subartist(String);
+
+/// `#MAKER string`
+///
+/// Sometimes supported.
+///
+/// Used to denote when a composer differs from the chart maker. In this case
+/// it is used to store the chart makers name.
+pub struct Maker(String);
+
+/// `#GENRE string`
+///
+/// Denotes the genre of music for the chart.
+/// By default it will be empty if not set.
+///
+/// Supported by basically every client.
+pub struct Genre(String);
+
+// TODO: Landmine
+// It's in WAV00
+
+/// `#BPM n`
+///
+/// Defines the BPM of the music. Defines the scroll speed etc.
+/// The BMS spec defines 130 as the default value.
+///
+/// it is expected that fractional BPMs are supported, as such we will repr
+/// this as a float.
+pub struct ConstantBPM(f32);
+
+// Standard defined default.
+// TODO. Implement BPM changes
+impl Default for ConstantBPM {
+    fn default() -> Self {
+        Self(130.0)
+    }
+}
+
+/// `#BPMxx n` OR `#EXBPM[01-ZZ] n`
+///
+/// Hitkey refers to this as exBPM or "Extended BPM Change Command".
+/// This operates on Channel #xxx08.
+///
+/// This command allows the chart designer to describe BPM changes.
+/// For example,
+///
+/// ```
+/// #BPMAA 256
+/// #BPMBB 155.5
+/// #00108:AABBAABB
+/// ```
+///
+/// This defines the BPM AA to be 256, the BPM BB to be 155.5 and says where to use it
+/// in the chart itself.
+///
+/// Negative BPMs are allowed, and in general are expected to make the chart scroll _backwards_.
+///
+/// For more info, see https://hitkey.nekokan.dyndns.info/exbpm-object.htm
+///
+/// In parsing, we expect to parse the identifier to the string, and the bpm to the float.
+pub struct ExBPM(String, f32);
+
+/// Represent the multiple types of BPM as enum variants.
+pub enum BPM {
+    Constant(ConstantBPM),
+    Extended(ExBPM),
+}
+
+/// `#STOP[01-ZZ] n`
+pub struct Stop(String, u32);

parser/src/lib.rs

@@ -1,14 +1 @@
-pub fn add(left: u64, right: u64) -> u64 {
+pub mod header;
-    left + right
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn it_works() {
-        let result = add(2, 2);
-        assert_eq!(result, 4);
-    }
-}

player/Cargo.toml

@@ -5,3 +5,12 @@ edition = "2024"
 
 [dependencies]
 bevy = { version = "0.16.1", features = ["dynamic_linking"] }
+
+
+# Enable a small amount of optimization in the dev profile.
+[profile.dev]
+opt-level = 1
+
+# Enable a large amount of optimization in the dev profile for dependencies.
+[profile.dev.package."*"]
+opt-level = 3