progress

gpx-rs/engine/data/with_highway.gpx

@@ -0,0 +1,58 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<gpx xmlns="http://www.topografix.com/GPX/1/1"
+    xmlns:gpxtpx="http://www.garmin.com/xmlschemas/TrackPointExtension/v1" version="1.1" creator="https://gpx.studio">
+    <metadata>
+        <name>with_highway</name>
+    </metadata>
+    <trk>
+        <name>with_highway</name>
+        <trkseg>
+            <trkpt lat="50.790867" lon="4.404968">
+                <ele>109.0</ele>
+                <extensions>
+                    <gpxtpx:TrackPointExtension>
+                        <gpxtpx:Extensions>
+                            <surface>asphalt</surface>
+                            <highway>residential</highway>
+                        </gpxtpx:Extensions>
+                    </gpxtpx:TrackPointExtension>
+                </extensions>
+            </trkpt>
+            <trkpt lat="50.791000" lon="4.405100">
+                <ele>110.0</ele>
+                <extensions>
+                    <gpxtpx:TrackPointExtension>
+                        <gpxtpx:Extensions>
+                            <surface>asphalt</surface>
+                            <highway>residential</highway>
+                        </gpxtpx:Extensions>
+                    </gpxtpx:TrackPointExtension>
+                </extensions>
+            </trkpt>
+            <trkpt lat="50.791200" lon="4.405300">
+                <ele>111.0</ele>
+            </trkpt>
+            <trkpt lat="50.791400" lon="4.405500">
+                <ele>112.0</ele>
+                <extensions>
+                    <gpxtpx:TrackPointExtension>
+                        <gpxtpx:Extensions>
+                            <surface>gravel</surface>
+                            <highway>track</highway>
+                        </gpxtpx:Extensions>
+                    </gpxtpx:TrackPointExtension>
+                </extensions>
+            </trkpt>
+            <trkpt lat="50.791600" lon="4.405700">
+                <ele>113.0</ele>
+                <extensions>
+                    <gpxtpx:TrackPointExtension>
+                        <gpxtpx:Extensions>
+                            <surface>gravel</surface>
+                        </gpxtpx:Extensions>
+                    </gpxtpx:TrackPointExtension>
+                </extensions>
+            </trkpt>
+        </trkseg>
+    </trk>
+</gpx>

gpx-rs/engine/src/core/gpx/categories.rs

@@ -0,0 +1,90 @@
+/// Maps the values of a category of trackpoint data (the surface, the highway...) to small codes,
+/// so that the trackpoints only hold a `u8` instead of a string.
+///
+/// The codes are the positions of the names in the order of first appearance. The table only
+/// grows: a code never changes meaning, so it stays valid in every state of the history.
+#[derive(Debug, Default, Clone, PartialEq)]
+pub struct Categories(Vec<String>);
+
+impl Categories {
+    /// Maximum number of distinct values.
+    pub const CAPACITY: usize = u8::MAX as usize;
+
+    /// The code of `name`, which is added to the table if it is new. `None` if the table is full.
+    pub fn code(&mut self, name: &str) -> Option<u8> {
+        let index = match self.0.iter().position(|known| known == name) {
+            Some(index) => index,
+            None if self.0.len() < Self::CAPACITY => {
+                self.0.push(name.to_owned());
+                self.0.len() - 1
+            }
+            None => return None,
+        };
+        u8::try_from(index).ok()
+    }
+
+    /// The name of a code, `None` if it is unknown.
+    pub fn name(&self, code: u8) -> Option<&str> {
+        self.0.get(usize::from(code)).map(String::as_str)
+    }
+
+    /// All the names, in the order of their codes.
+    pub fn names(&self) -> &[String] {
+        &self.0
+    }
+}
+
+/// The categories of the data of the trackpoints. There is one table per engine, shared by all
+/// its files.
+#[derive(Debug, Default, Clone, PartialEq)]
+pub struct TrackpointCategories {
+    pub surface: Categories,
+    pub highway: Categories,
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_codes_follow_the_order_of_appearance() {
+        let mut categories = Categories::default();
+        assert_eq!(categories.code("asphalt"), Some(0));
+        assert_eq!(categories.code("gravel"), Some(1));
+        // a known name keeps its code
+        assert_eq!(categories.code("asphalt"), Some(0));
+        assert_eq!(categories.names(), ["asphalt", "gravel"]);
+    }
+
+    #[test]
+    fn test_names_of_codes() {
+        let mut categories = Categories::default();
+        let code = categories.code("asphalt").unwrap();
+        assert_eq!(categories.name(code), Some("asphalt"));
+        assert_eq!(categories.name(code + 1), None);
+        assert_eq!(Categories::default().name(0), None);
+    }
+
+    #[test]
+    fn test_a_full_table_gives_no_code_to_new_names() {
+        let mut categories = Categories::default();
+        for i in 0..Categories::CAPACITY {
+            assert_eq!(categories.code(&i.to_string()), Some(i as u8));
+        }
+        assert_eq!(categories.code("one too many"), None);
+        assert_eq!(categories.names().len(), Categories::CAPACITY);
+        // the known ones still have their code, the last one included
+        assert_eq!(categories.code("0"), Some(0));
+        assert_eq!(categories.code("254"), Some(254));
+        assert_eq!(categories.name(254), Some("254"));
+    }
+
+    #[test]
+    fn test_the_categories_are_independent() {
+        let mut categories = TrackpointCategories::default();
+        categories.surface.code("asphalt");
+        assert_eq!(categories.highway.code("path"), Some(0));
+        assert_eq!(categories.surface.names(), ["asphalt"]);
+        assert_eq!(categories.highway.names(), ["path"]);
+    }
+}

gpx-rs/engine/src/core/gpx/mod.rs

@@ -1,3 +1,4 @@
+mod categories;
 mod chunk;
 mod common;
 mod file;
@@ -6,6 +7,7 @@ mod track;
 mod trackpoint;
 mod waypoint;
 
+pub use categories::*;
 pub use chunk::*;
 pub use common::*;
 pub use file::*;

gpx-rs/engine/src/core/gpx/trackpoint.rs

@@ -9,5 +9,8 @@ pub struct Trackpoint {
     pub hr: Option<u16>,
     pub cad: Option<u16>,
     pub power: Option<u16>,
-    // TODO OSM data? or store intervals at a higher level?
+    /// Code of the surface, see [`crate::TrackpointCategories`].
+    pub surface: Option<u8>,
+    /// Code of the highway, see [`crate::TrackpointCategories`].
+    pub highway: Option<u8>,
 }

gpx-rs/engine/src/core/io/parse.rs

@@ -1,8 +1,8 @@
 use std::rc::Rc;
 
 use crate::{
-    Author, File, Link, LngLat, Track, TrackSegment, Trackpoint, TrackpointChunk, Waypoint,
-    WaypointChunk,
+    Author, File, Link, LngLat, Track, TrackSegment, Trackpoint, TrackpointCategories,
+    TrackpointChunk, Waypoint, WaypointChunk,
 };
 use chrono::DateTime;
 use quick_xml::Error;
@@ -29,6 +29,8 @@ enum GPXElement {
     Heartrate,
     Cadence,
     Power,
+    Surface,
+    Highway,
     Symbol,
     Type,
     Color,
@@ -48,7 +50,9 @@ fn parse_coordinates(attributes: Attributes<'_>) -> LngLat {
     coordinates
 }
 
-pub fn parse(data: &[u8]) -> Result<File, Error> {
+/// Parses a GPX file. The surface and the highway of the trackpoints are stored as codes of
+/// `categories`, which learns the values it does not know yet.
+pub fn parse(data: &[u8], categories: &mut TrackpointCategories) -> Result<File, Error> {
     let mut reader = Reader::from_reader(data);
     let mut buf = vec![];
     let mut gpx = File::default();
@@ -95,8 +99,10 @@ pub fn parse(data: &[u8]) -> Result<File, Error> {
                 e if e.ends_with("atemp") => stack.push(GPXElement::Temperature),
                 e if e.ends_with("hr") => stack.push(GPXElement::Heartrate),
                 e if e.ends_with("cad") => stack.push(GPXElement::Cadence),
-                "power" => stack.push(GPXElement::Power),
+                e if e.ends_with("power") => stack.push(GPXElement::Power),
                 e if e.ends_with("PowerInWatts") => stack.push(GPXElement::Power),
+                "surface" => stack.push(GPXElement::Surface),
+                "highway" => stack.push(GPXElement::Highway),
                 "sym" => stack.push(GPXElement::Symbol),
                 "type" => stack.push(GPXElement::Type),
                 e if e.ends_with("color") => stack.push(GPXElement::Color),
@@ -270,6 +276,18 @@ pub fn parse(data: &[u8]) -> Result<File, Error> {
                         trkpt.power = e.parse().ok();
                     }
                 }
+                Some(GPXElement::Surface) => {
+                    stack.pop();
+                    if let Some(GPXElement::Trackpoint(trkpt)) = stack.last_mut() {
+                        trkpt.surface = categories.surface.code(&e);
+                    }
+                }
+                Some(GPXElement::Highway) => {
+                    stack.pop();
+                    if let Some(GPXElement::Trackpoint(trkpt)) = stack.last_mut() {
+                        trkpt.highway = categories.highway.code(&e);
+                    }
+                }
                 Some(GPXElement::Symbol) => {
                     stack.pop();
                     if let Some(GPXElement::Waypoint(wpt)) = stack.last_mut() {
@@ -322,7 +340,11 @@ mod tests {
     use super::*;
 
     fn parse_data(name: &str) -> File {
-        parse(&std::fs::read(format!("data/{name}.gpx")).unwrap()).unwrap()
+        parse(
+            &std::fs::read(format!("data/{name}.gpx")).unwrap(),
+            &mut Default::default(),
+        )
+        .unwrap()
     }
 
     #[test]
@@ -513,6 +535,88 @@ mod tests {
         assert!(trkpt.hr.is_some_and(|h| h == 150));
     }
 
+    fn parse_data_with_categories(name: &str) -> (File, TrackpointCategories) {
+        let mut categories = TrackpointCategories::default();
+        let file = parse(
+            &std::fs::read(format!("data/{name}.gpx")).unwrap(),
+            &mut categories,
+        )
+        .unwrap();
+        (file, categories)
+    }
+
+    #[test]
+    fn test_parse_trackpoint_surface() {
+        let (gpx, categories) = parse_data_with_categories("with_surface");
+
+        let trkseg = &gpx.trk[0].trkseg[0];
+        assert_eq!(trkseg.len(), 80);
+        // the codes follow the order of appearance in the file
+        assert_eq!(categories.surface.names(), ["asphalt", "cobblestone"]);
+        let asphalt = Some(0);
+        let cobblestone = Some(1);
+        assert_eq!(trkseg.iter().filter(|p| p.surface == asphalt).count(), 79);
+        assert_eq!(
+            trkseg.iter().filter(|p| p.surface == cobblestone).count(),
+            1
+        );
+        // no highway in this file
+        assert!(trkseg.iter().all(|trkpt| trkpt.highway.is_none()));
+        assert!(categories.highway.names().is_empty());
+    }
+
+    #[test]
+    fn test_parse_trackpoint_surface_and_highway() {
+        let (gpx, categories) = parse_data_with_categories("with_highway");
+
+        let trkseg = &gpx.trk[0].trkseg[0];
+        let names = |code: Option<u8>, names: &crate::Categories| {
+            code.and_then(|code| names.name(code)).map(str::to_owned)
+        };
+        let values: Vec<_> = trkseg
+            .iter()
+            .map(|trkpt| {
+                (
+                    names(trkpt.surface, &categories.surface),
+                    names(trkpt.highway, &categories.highway),
+                )
+            })
+            .collect();
+        let some = |s: &str| Some(s.to_owned());
+        assert_eq!(
+            values,
+            [
+                (some("asphalt"), some("residential")),
+                (some("asphalt"), some("residential")),
+                (None, None),
+                (some("gravel"), some("track")),
+                (some("gravel"), None),
+            ]
+        );
+    }
+
+    #[test]
+    fn test_parse_shares_the_categories_between_files() {
+        let mut categories = TrackpointCategories::default();
+        let mut parsed = |name: &str| {
+            parse(
+                &std::fs::read(format!("data/{name}.gpx")).unwrap(),
+                &mut categories,
+            )
+            .unwrap()
+        };
+        let first = parsed("with_highway");
+        let second = parsed("with_surface");
+        let code = |file: &File, i: usize| file.trk[0].trkseg[0][i].surface;
+        // "asphalt" is the same in both, "cobblestone" comes after "gravel"
+        assert_eq!(code(&first, 0), Some(0));
+        assert_eq!(code(&second, 0), Some(0));
+        assert_eq!(
+            categories.surface.names(),
+            ["asphalt", "gravel", "cobblestone"]
+        );
+    }
+
     #[test]
     fn test_parse_trackpoint_cad() {
         let gpx = parse_data("with_cad");

gpx-rs/engine/src/core/statistics/statistics.rs

@@ -331,7 +331,7 @@ mod tests {
         let mut f = File::open("data/with_time.gpx").unwrap();
         let mut data = String::new();
         let _ = f.read_to_string(&mut data);
-        let gpx = parse(data.as_bytes()).unwrap();
+        let gpx = parse(data.as_bytes(), &mut Default::default()).unwrap();
 
         let trkseg = &gpx.trk[0].trkseg[0];
         let stats = Statistics::compute(trkseg);
@@ -348,7 +348,7 @@ mod tests {
         let mut f = File::open(path).unwrap();
         let mut data = String::new();
         let _ = f.read_to_string(&mut data);
-        parse(data.as_bytes()).unwrap()
+        parse(data.as_bytes(), &mut Default::default()).unwrap()
     }
 
     #[test]
@@ -482,7 +482,7 @@ mod tests {
             ("data/with_power_1.gpx", 3),
         ] {
             let data = std::fs::read(path).unwrap();
-            let gpx = parse(&data).unwrap();
+            let gpx = parse(&data, &mut Default::default()).unwrap();
             let trkseg = &gpx.trk[0].trkseg[0];
             let global = Statistics::compute(trkseg).global;
             let values: Vec<f64> = trkseg

gpx-rs/engine/src/engine/command/file/load.rs

@@ -1,4 +1,4 @@
-use crate::{Apply, CommandError, File, State, parse, produce};
+use crate::{Apply, CommandError, File, State, TrackpointCategories, parse, produce};
 
 #[derive(Debug)]
 pub struct Load<'a> {
@@ -9,9 +9,9 @@ pub struct Load<'a> {
 }
 
 impl Load<'_> {
-    fn parse(self) -> Result<File, CommandError> {
-        let mut file =
-            parse(self.data).map_err(|err| CommandError::InvalidData(err.to_string()))?;
+    fn parse(self, categories: &mut TrackpointCategories) -> Result<File, CommandError> {
+        let mut file = parse(self.data, categories)
+            .map_err(|err| CommandError::InvalidData(err.to_string()))?;
         if file.info.name.trim().is_empty() {
             file.info.name = self.name.to_owned();
         }
@@ -40,7 +40,7 @@ impl Apply for LoadFiles<'_> {
         let mut files = Vec::with_capacity(self.files.len());
         let mut first_error = None;
         for load in self.files {
-            match load.parse() {
+            match load.parse(state.categories) {
                 Ok(file) => files.push(file),
                 Err(error) => {
                     first_error.get_or_insert(error);

gpx-rs/engine/src/engine/command/fixture.rs

@@ -2,7 +2,7 @@
 
 use std::collections::HashSet;
 
-use crate::{Clipboard, FileId, FileOrder, Selection, StackEntry, State};
+use crate::{Clipboard, FileId, FileOrder, Selection, StackEntry, State, TrackpointCategories};
 
 #[derive(Default)]
 pub struct Fixture {
@@ -10,11 +10,13 @@ pub struct Fixture {
     pub selection: Selection,
     pub order: FileOrder,
     pub clipboard: Option<Clipboard>,
+    pub categories: TrackpointCategories,
 }
 
 impl Fixture {
     pub fn state(&mut self) -> State<'_> {
         State {
+            categories: &mut self.categories,
             files: &mut self.files,
             selection: &mut self.selection,
             order: &mut self.order,

gpx-rs/engine/src/engine/command/pattern/update_selected.rs

@@ -179,7 +179,7 @@ mod tests {
     fn fixture_with_tracks() -> (Fixture, FileId) {
         let mut fx = Fixture::default();
         let data = std::fs::read("data/with_tracks_and_segments.gpx").unwrap();
-        let file = Rc::new(crate::parse(&data).unwrap());
+        let file = Rc::new(crate::parse(&data, &mut Default::default()).unwrap());
         let id = file.id;
         fx.files.insert(id, file);
         (fx, id)

gpx-rs/engine/src/engine/derived/statistics_buffer.rs

@@ -33,6 +33,17 @@ pub struct StatisticsBuffer {
     pub cad: Vec<f64>,
     pub atemp: Vec<f64>,
     pub power: Vec<f64>,
+    /// Surface of the trackpoints: 0 when unknown, else 1 + its code in the categories of the
+    /// engine (so that it is never 0 for a known surface).
+    pub surface: Vec<u8>,
+    /// Highway of the trackpoints, as the surface.
+    pub highway: Vec<u8>,
+}
+
+/// 0 for an unknown value, else the code plus one. The categories hold at most 255 values, so it
+/// fits.
+fn unknown_or_next(code: Option<u8>) -> u8 {
+    code.and_then(|code| code.checked_add(1)).unwrap_or(0)
 }
 
 impl StatisticsBuffer {
@@ -65,6 +76,8 @@ impl StatisticsBuffer {
         self.cad.clear();
         self.atemp.clear();
         self.power.clear();
+        self.surface.clear();
+        self.highway.clear();
 
         let optional = |value: Option<f64>| value.unwrap_or(f64::NAN);
 
@@ -102,6 +115,8 @@ impl StatisticsBuffer {
                 self.cad.push(optional(trkpt.cad.map(f64::from)));
                 self.atemp.push(optional(trkpt.atemp.map(f64::from)));
                 self.power.push(optional(trkpt.power.map(f64::from)));
+                self.surface.push(unknown_or_next(trkpt.surface));
+                self.highway.push(unknown_or_next(trkpt.highway));
             }
             self.global.merge(&stats.global);
         }
@@ -153,7 +168,7 @@ mod tests {
 
     fn computed(path: &str) -> (TrackSegment, Statistics) {
         let data = std::fs::read(path).unwrap();
-        let file = parse(&data).unwrap();
+        let file = parse(&data, &mut Default::default()).unwrap();
         let segment = file.trk[0].trkseg[0].clone();
         let stats = Statistics::compute(&segment);
         (segment, stats)
@@ -179,6 +194,8 @@ mod tests {
             buffer.cad.len(),
             buffer.atemp.len(),
             buffer.power.len(),
+            buffer.surface.len(),
+            buffer.highway.len(),
         ]
     }
 
@@ -278,6 +295,45 @@ mod tests {
         assert_eq!(buffer.global.total_time, None);
     }
 
+    #[test]
+    fn test_surface_and_highway_codes() {
+        let (segment, s) = computed("data/with_highway.gpx");
+        let mut buffer = StatisticsBuffer::default();
+        buffer.update(&[(&segment, &s)]);
+
+        // 0 for the trackpoints that have none, else the code of the engine plus one
+        assert_eq!(buffer.surface, [1, 1, 0, 2, 2]);
+        assert_eq!(buffer.highway, [1, 1, 0, 2, 0]);
+        assert!(all_lengths(&buffer).iter().all(|len| *len == 5));
+    }
+
+    #[test]
+    fn test_codes_of_the_trackpoints_are_used_as_they_are() {
+        let (mut segment, _) = computed("data/simple.gpx");
+        let mut point = segment[0].clone();
+        point.surface = Some(7);
+        point.highway = Some(254);
+        segment.splice(0, 1, vec![point]);
+        let s = Statistics::compute(&segment);
+        let mut buffer = StatisticsBuffer::default();
+        buffer.update(&[(&segment, &s)]);
+        assert_eq!((buffer.surface[0], buffer.highway[0]), (8, 255));
+        assert_eq!((buffer.surface[1], buffer.highway[1]), (0, 0));
+    }
+
+    #[test]
+    fn test_no_codes_without_surface_and_highway() {
+        let (segment, s) = computed("data/simple.gpx");
+        let mut buffer = StatisticsBuffer::default();
+        buffer.update(&[(&segment, &s)]);
+        assert_eq!(buffer.surface.len(), s.local.len());
+        assert!(buffer.surface.iter().all(|c| *c == 0));
+        assert!(buffer.highway.iter().all(|c| *c == 0));
+        // and they are reset by the next update
+        buffer.update(&[]);
+        assert!(buffer.surface.is_empty() && buffer.highway.is_empty());
+    }
+
     #[test]
     fn test_update_replaces_previous_content() {
         let (segment, s) = computed("data/simple.gpx");
@@ -344,7 +400,7 @@ mod tests {
     #[test]
     fn test_slice_keeps_the_bounds_and_averages_of_the_selection() {
         let data = std::fs::read("data/with_hr.gpx").unwrap();
-        let file = parse(&data).unwrap();
+        let file = parse(&data, &mut Default::default()).unwrap();
         let segment = file.trk[0].trkseg[0].clone();
         let s = Statistics::compute(&segment);
         let mut buffer = StatisticsBuffer::default();

gpx-rs/engine/src/engine/derived/statistics_cache.rs

@@ -161,7 +161,7 @@ mod tests {
 
     fn state(path: &str) -> (StackEntry, Rc<File>) {
         let data = std::fs::read(path).unwrap();
-        let file = Rc::new(parse(&data).unwrap());
+        let file = Rc::new(parse(&data, &mut Default::default()).unwrap());
         let mut state = StackEntry::default();
         state.insert(file.id, file.clone());
         (state, file)
@@ -273,7 +273,7 @@ mod tests {
         let (mut state, first) = state("data/simple.gpx");
         let (other, second) = {
             let data = std::fs::read("data/with_time.gpx").unwrap();
-            let file = Rc::new(parse(&data).unwrap());
+            let file = Rc::new(parse(&data, &mut Default::default()).unwrap());
             (file.clone(), file)
         };
         state.insert(other.id, other);

gpx-rs/engine/src/engine/engine.rs

@@ -3,7 +3,7 @@
 use crate::{
     Action, Apply, Clipboard, Command, CoordinatesCache, Diff, FileId, FileOrder, FileStructure,
     FileStructureCache, GlobalStatistics, SelectMode, Selection, Stack, State, StatisticsBuffer,
-    StatisticsCache, TrackSegmentId, Trackpoint, Waypoint, WaypointId,
+    StatisticsCache, TrackSegmentId, Trackpoint, TrackpointCategories, Waypoint, WaypointId,
 };
 
 #[derive(Debug, Default)]
@@ -18,6 +18,7 @@ pub struct Engine {
     order_changed: bool,
     selection_changed: bool,
     statistics_buffer: StatisticsBuffer,
+    categories: TrackpointCategories,
     clipboard: Option<Clipboard>,
     clipboard_changed: bool,
 }
@@ -27,6 +28,11 @@ impl Engine {
         &self.statistics_buffer
     }
 
+    /// The names of the surfaces and highways that the trackpoints refer to by code.
+    pub fn categories(&self) -> &TrackpointCategories {
+        &self.categories
+    }
+
     /// Files in display order.
     pub fn order(&self) -> &[FileId] {
         &self.order.0
@@ -216,6 +222,7 @@ impl Engine {
     fn edit(&mut self, command: Command) -> Option<Diff> {
         self.stack.create_and_push_next(|files| {
             let mut state = State {
+                categories: &mut self.categories,
                 files,
                 selection: &mut self.selection,
                 order: &mut self.order,
@@ -1231,6 +1238,52 @@ mod tests {
         assert!(engine.waypoint(&file, &id).is_some());
     }
 
+    #[test]
+    fn test_categories_are_shared_and_kept_by_the_history() {
+        let mut engine = Engine::default();
+        assert!(engine.categories().surface.names().is_empty());
+
+        load(&mut engine, "data/with_highway.gpx");
+        assert_eq!(engine.categories().surface.names(), ["asphalt", "gravel"]);
+        assert_eq!(
+            engine.categories().highway.names(),
+            ["residential", "track"]
+        );
+        // the trackpoints of the selection refer to them
+        assert_eq!(engine.statistics().surface, [1, 1, 0, 2, 2]);
+        assert_eq!(engine.statistics().highway, [1, 1, 0, 2, 0]);
+
+        // a second file goes on with the same table
+        load(&mut engine, "data/with_surface.gpx");
+        assert_eq!(
+            engine.categories().surface.names(),
+            ["asphalt", "gravel", "cobblestone"]
+        );
+        assert_eq!(engine.statistics().surface.len(), 80);
+        assert_eq!(engine.statistics().surface[0], 1);
+        assert_eq!(
+            engine
+                .statistics()
+                .surface
+                .iter()
+                .filter(|c| **c == 3)
+                .count(),
+            1
+        );
+
+        // undoing does not forget what was learned: the codes stay valid in every state
+        assert!(engine.execute(Action::Undo));
+        assert!(engine.execute(Action::Undo));
+        assert_eq!(
+            engine.categories().surface.names(),
+            ["asphalt", "gravel", "cobblestone"]
+        );
+        assert!(engine.execute(Action::Redo));
+        let first = engine.order()[0];
+        select_files(&mut engine, &[first]);
+        assert_eq!(engine.statistics().surface, [1, 1, 0, 2, 2]);
+    }
+
     #[test]
     fn test_trackpoint() {
         let mut engine = Engine::default();

gpx-rs/engine/src/engine/state/mod.rs

@@ -9,6 +9,7 @@ pub use selection::*;
 pub use stack::*;
 
 pub struct State<'a> {
+    pub categories: &'a mut crate::TrackpointCategories,
     pub files: &'a mut StackEntry,
     pub selection: &'a mut Selection,
     pub order: &'a mut FileOrder,

gpx-rs/wasm/src/lib.rs

@@ -14,7 +14,7 @@ use std::cell::RefCell;
 use wasm_bindgen::prelude::*;
 
 use gpx_engine::{self as engine, Action, Command, Engine, FileId, LngLat, LngLatBounds};
-use js_sys::{Array, BigInt64Array, Float64Array, Object, Reflect};
+use js_sys::{Array, BigInt64Array, Float64Array, Object, Reflect, Uint8Array};
 
 #[wasm_bindgen]
 #[derive(Clone, Copy)]
@@ -164,6 +164,28 @@ stats_getter!(cad, Float64Array);
 stats_getter!(atemp, Float64Array);
 stats_getter!(power, Float64Array);
 
+// Surface and highway of the trackpoints: 0 when unknown, else 1 + the index in `surfaces()` or
+// `highways()`.
+stats_getter!(surface, Uint8Array);
+stats_getter!(highway, Uint8Array);
+
+/// The names of the surfaces, in the order of their codes (see `surface`). The list only grows:
+/// a name keeps its index.
+#[wasm_bindgen]
+pub fn surfaces() -> StringList {
+    with_engine(|e| array(e.categories().surface.names(), |name| name.as_str().into()))
+        .unwrap_or_default()
+        .unchecked_into()
+}
+
+/// The names of the highways, in the order of their codes (see `highway`).
+#[wasm_bindgen]
+pub fn highways() -> StringList {
+    with_engine(|e| array(e.categories().highway.names(), |name| name.as_str().into()))
+        .unwrap_or_default()
+        .unchecked_into()
+}
+
 // File commands
 
 #[wasm_bindgen]
@@ -803,6 +825,8 @@ extern "C" {
     pub type GlobalStatistics;
     #[wasm_bindgen(typescript_type = "string[]")]
     pub type FileOrder;
+    #[wasm_bindgen(typescript_type = "string[]")]
+    pub type StringList;
 }
 
 fn set(object: &Object, key: &str, value: impl Into<JsValue>) {

website/src/lib/components/elevation-profile/elevation-profile.ts

@@ -25,6 +25,7 @@ import type { Coordinates } from 'gpx';
 import { NO_TIME, type SelectionStatistics } from '$lib/engine';
 import type { SlicedStatistics } from '$lib/logic/selection-statistics';
 import { mode } from 'mode-watcher';
+import { categoryAt } from '$lib/trackpoint-categories';
 import { getHighwayColor, getSlopeColor, getSurfaceColor } from '$lib/assets/colors';
 
 const { distanceUnits, velocityUnits, temperatureUnits } = settings;
@@ -41,7 +42,8 @@ interface ElevationProfilePoint {
         segment: number;
         length: number;
     };
-    extensions: Record<string, any>;
+    surface?: string;
+    highway?: string;
     coordinates: Coordinates;
     index: number;
 }
@@ -185,14 +187,11 @@ export class ElevationProfile {
                                 segment: point.slope.segment.toFixed(1),
                                 length: getDistanceWithUnits(point.slope.length),
                             };
-                            let surface = point.extensions.surface
-                                ? point.extensions.surface
-                                : 'unknown';
-                            let highway = point.extensions.highway
-                                ? point.extensions.highway
-                                : 'unknown';
-                            let sacScale = point.extensions.sac_scale;
-                            let mtbScale = point.extensions.mtb_scale;
+                            let surface = point.surface ?? 'unknown';
+                            let highway = point.highway ?? 'unknown';
+                            // TODO the engine does not store the sac and mtb scales yet
+                            let sacScale: string | undefined = undefined;
+                            let mtbScale: string | undefined = undefined;
 
                             let labels = [
                                 `    ${i18n._('quantities.distance')}: ${getDistanceWithUnits(point.x, false)}`,
@@ -413,8 +412,8 @@ export class ElevationProfile {
                     segment: data.slopeSegmentSlope[index],
                     length: data.slopeSegmentDistance[index],
                 },
-                // TODO the engine does not store the extensions (surface, highway...) yet
-                extensions: data.extensions[index] ?? {},
+                surface: categoryAt(data.surface, data.surfaces, index),
+                highway: categoryAt(data.highway, data.highways, index),
                 coordinates: { lat: data.lat[index], lon: data.lng[index] },
                 index,
             });
@@ -602,16 +601,13 @@ export class ElevationProfile {
 
     surfaceFillCallback(context: ScriptableLineSegmentContext & { p0: { raw: any } }) {
         const point = context.p0.raw as ElevationProfilePoint;
-        return getSurfaceColor(point.extensions.surface);
+        return getSurfaceColor(point.surface ?? '');
     }
 
     highwayFillCallback(context: ScriptableLineSegmentContext & { p0: { raw: any } }) {
         const point = context.p0.raw as ElevationProfilePoint;
-        return getHighwayColor(
-            point.extensions.highway,
-            point.extensions.sac_scale,
-            point.extensions.mtb_scale
-        );
+        // TODO the engine does not store the sac and mtb scales yet
+        return getHighwayColor(point.highway ?? '', undefined, undefined);
     }
 
     destroy() {

website/src/lib/engine.ts

@@ -140,11 +140,14 @@ export type SelectionStatistics = {
     cad: Float64Array;
     atemp: Float64Array;
     power: Float64Array;
-    /**
-     * Extensions of the trackpoints (surface, highway...), or an empty array when they are not
-     * known. TODO the engine does not store them yet.
-     */
-    extensions: Record<string, string>[];
+    /** Surface of the trackpoints: 0 when unknown, else 1 + the index in `surfaces`. */
+    surface: Uint8Array;
+    /** Names of the surfaces, by code: a name keeps its index. */
+    surfaces: string[];
+    /** Highway of the trackpoints: 0 when unknown, else 1 + the index in `highways`. */
+    highway: Uint8Array;
+    /** Names of the highways, by code. */
+    highways: string[];
     /**
      * Global statistics of the trackpoints from `start` to `end` (both included), for example
      * the part of the elevation profile that was dragged over. `undefined` if the range is not
@@ -174,7 +177,10 @@ const EMPTY_SELECTION_STATISTICS: SelectionStatistics = {
     cad: new Float64Array(),
     atemp: new Float64Array(),
     power: new Float64Array(),
-    extensions: [],
+    surface: new Uint8Array(),
+    surfaces: [],
+    highway: new Uint8Array(),
+    highways: [],
     slice: () => undefined,
 };
 
@@ -625,7 +631,10 @@ class Engine {
             cad: wasm.cad().slice(),
             atemp: wasm.atemp().slice(),
             power: wasm.power().slice(),
-            extensions: [],
+            surface: wasm.surface().slice(),
+            surfaces: wasm.surfaces(),
+            highway: wasm.highway().slice(),
+            highways: wasm.highways(),
             slice: (start, end) =>
                 version === this._statisticsVersion ? wasm.slice_statistics(start, end) : undefined,
         };

website/src/lib/trackpoint-categories.test.ts

@@ -0,0 +1,24 @@
+import { describe, it } from 'node:test';
+import assert from 'node:assert/strict';
+import { categoryAt } from './trackpoint-categories';
+
+describe('categoryAt', () => {
+    const codes = new Uint8Array([1, 1, 0, 2, 0]);
+    const names = ['asphalt', 'gravel'];
+
+    it('is the name of the code', () => {
+        assert.equal(categoryAt(codes, names, 0), 'asphalt');
+        assert.equal(categoryAt(codes, names, 3), 'gravel');
+    });
+
+    it('is undefined when the value is unknown', () => {
+        assert.equal(categoryAt(codes, names, 2), undefined);
+        assert.equal(categoryAt(codes, names, 4), undefined);
+    });
+
+    it('is undefined out of the trackpoints, or for a code without name', () => {
+        assert.equal(categoryAt(codes, names, 5), undefined);
+        assert.equal(categoryAt(new Uint8Array([3]), names, 0), undefined);
+        assert.equal(categoryAt(new Uint8Array(), [], 0), undefined);
+    });
+});

website/src/lib/trackpoint-categories.ts

@@ -0,0 +1,12 @@
+/**
+ * The value of a trackpoint for a category of the engine (surface, highway): `codes` has one entry
+ * per trackpoint, 0 when the value is unknown, else 1 + the index of the value in `names`.
+ */
+export function categoryAt(
+    codes: ArrayLike<number>,
+    names: readonly string[],
+    index: number
+): string | undefined {
+    const code = codes[index];
+    return code ? names[code - 1] : undefined;
+}

website/src/routes/[[language]]/+page.svelte

@@ -45,7 +45,10 @@
         cad: new Float64Array(),
         atemp: new Float64Array(),
         power: new Float64Array(),
-        extensions: [],
+        surface: new Uint8Array(),
+        surfaces: [],
+        highway: new Uint8Array(),
+        highways: [],
         slice: () => undefined,
     });
     let slicedStatistics = writable(undefined);