Render NOBJNM national language names

docs/docs/api/style.md

@@ -43,6 +43,12 @@ typedef struct tile57_mariner {
     double sounding_size_scale;     /* extra size multiplier for SOUNDINGS, on top of
                                      * size_scale (scales each digit + spacing together).
                                      * 1.0 = none; 0 reads as 1.0. */
+    uint8_t soundings;              /* spot soundings, independent of the display
+                                     * category. 0 = follow the category, 1 = always
+                                     * show, 2 = always hide. S-52 files SOUNDG under
+                                     * OTHER, so 0 means a host enables the whole OTHER
+                                     * category to get soundings, and takes the seabed
+                                     * and the cables with it. */
     double device_scale;            /* device px per reference px — the HiDPI density the
                                      * SURFACE paths are drawn at (2.0 on a Retina backing
                                      * store). Describes the DISPLAY where size_scale
@@ -52,6 +58,22 @@ typedef struct tile57_mariner {
                                      * it (that density is already in the requested
                                      * width/height). 1.0 = a 1x framebuffer; 0 reads as
                                      * 1.0. */
+    bool chart_over_image;          /* CHART OVER PICTURE: a raster chart is drawn
+                                     * beneath this one, so the DEPARE / DRGARE / UNSARE
+                                     * / LNDARE fills and the no-data background drop
+                                     * out and the picture shows through. Contours,
+                                     * symbols, lights, soundings, text and boundaries
+                                     * already drawn as lines or patterns stay. Engages
+                                     * the S-52 §10.3.4.2 DisplayPlane precedence, which
+                                     * the clause conditions on an image beneath the
+                                     * chart; radar_overlay satisfies the same gate. */
+    char preferred_language[4];     /* the mariner's label language, an ISO 639-2 code
+                                     * such as "zho", or "" for the portrayed name. A code
+                                     * the chart states draws that language's name; any
+                                     * other code still draws an S-57 national name
+                                     * (NOBJNM), which records no language. The bake
+                                     * stores each language beside the portrayed name, so
+                                     * this switches without a re-bake. */
 } tile57_mariner;
 
 void tile57_mariner_defaults(tile57_mariner *m);   /* canonical defaults, date_view = "" */

docs/docs/limitations.md

@@ -51,6 +51,12 @@ result is **best effort**:
 - **Missing S-101 content stays missing.** S-101 attributes and features with
   no S-57 source are never invented; rules that test them take their fallback
   branch.
+- **A national name has no language.** S-57 stores one `NOBJNM` per feature and
+  records only the lexical level of the text (part 3 clause 2.4), which is a
+  character repertoire rather than a language. The adapter converts it to a
+  second `featureName` tagged ISO 639-2 `und`, undetermined, so the
+  mariner's language setting reaches it whatever code they ask for. S-101 permits several `featureName` entries with distinct
+  languages. An S-57 source yields at most one.
 - **Unconvertible objects fall back or drop.** An S-57 object class with no
   S-101 equivalent portrays as the S-52 question mark (QUESMRK1) — or, where
   the S-65 guidance says the object is simply not carried into S-101 (e.g. an
@@ -95,6 +101,18 @@ result is **best effort**:
 
 ## Display / style gaps
 
+- **The embedded font covers Latin, Greek and Cyrillic.** A label in another
+  script draws with the bundled Noto Sans, which has no glyphs for it, and comes
+  out as boxes. Point `TILE57_FONT_FALLBACK` at a TrueType file or collection
+  holding the script, and the pixel outputs draw each codepoint the bundled face
+  lacks from that one. The PDF and vector outputs embed a single face per label,
+  so a label mixing scripts still draws its fallback glyphs from the bundled
+  face there. A host that supplies its own face through the surface callbacks is
+  unaffected.
+- **A chart states more than four languages.** The bake runs a portrayal pass
+  per language and stores a text property per language, so it keeps the first
+  four it finds and drops the rest.
+
 - **Overscale hatch occlusion is tile-path only.** The S-52 §10.1.10 overscale
   indication (`OVERSC01`, see [architecture](./architecture.md)) is gated
   correctly everywhere, but only the generated MapLibre style sandwiches the

docs/docs/rendering.md

@@ -119,7 +119,7 @@ tile57 png chart.pmtiles --view -76.48,38.974,15.1 --size 1024x768 -o out.png
 
 # Mariner settings
 tile57 png ... --safety 5 --safety-depth 5 --feet --palette night \
-               --no-names --plain --simplified --dq --scale 1.5
+               --no-names --language zho --plain --simplified --dq --scale 1.5
 ```
 
 ### From C (and therefore Go, Python, C++, …)

docs/docs/tile-schema.md

@@ -146,11 +146,12 @@ Depth soundings, drawn as digit glyph strings (SNDFRM digit composition).
 ### text
 
 Text labels (the name typically derives from `OBJNAM` via the `featureName`
-attribute).
+attribute; a feature named in other languages also gets a `text_<lang>` for each).
 
 | Field | Type | Meaning |
 | --- | --- | --- |
 | `text` | string | The label text. |
+| `text_<lang>` | string | The same label in one of the languages the chart states, keyed by ISO 639-2 code, one property per language. An S-57 national name (`NOBJNM`) is keyed `text_und`, because S-57 records no language for it. A client selects with the mariner's language without a re-bake. |
 | `font_size_px` | number | Font size in pixels. |
 | `color_token` | string | Text color name. |
 | `halo_color_token` | string | Halo color name (`""` = no halo). |

include/tile57.h

@@ -720,6 +720,15 @@ typedef struct tile57_mariner {
                          * specified values and blending them produces colours the
                          * spec does not name.
                          * Appended for ABI-append-safety; a zeroed struct is off. */
+    char preferred_language[4]; /* The mariner's label language, an ISO 639-2
+                         * code such as "zho", or "" for the portrayed name. A
+                         * code the chart states draws that language's name. Any
+                         * other code still draws an S-57 national name (NOBJNM),
+                         * because S-57 records no language for it.
+                         * The bake stores each language the chart states beside
+                         * the portrayed name, so this switches without a
+                         * re-bake. Appended for ABI-append-safety; a zeroed
+                         * struct keeps the portrayed name. */
 } tile57_mariner;
 
 /* Fill *m with the canonical default mariner settings (so a host needn't

src/capi.zig

@@ -2219,6 +2219,14 @@ export fn tile57_assets_free(out: ?*CAssets) callconv(.c) void {
 
 // ---- chart-style generation (mirrors tile57_mariner in tile57.h) -----------
 
+/// The mariner language as the ABI's fixed field. A code longer than the field
+/// holds is dropped, which reads as the portrayed name.
+fn langCode(s: []const u8) [4]u8 {
+    var out = [_]u8{0} ** 4;
+    if (s.len < out.len) @memcpy(out[0..s.len], s);
+    return out;
+}
+
 const CMariner = extern struct {
     scheme: c_int,
     shallow_contour: f64,
@@ -2280,6 +2288,11 @@ const CMariner = extern struct {
     // background so a raster chart beneath shows through, and engage the
     // DisplayPlane precedence. See tile57.h. Appended for ABI-append-safety.
     chart_over_image: bool,
+    // The mariner's label language, an ISO 639-2 code, or "" for the portrayed
+    // name. The bake stores each language the chart states beside that name, so
+    // this switches without a re-bake. Appended for ABI-append-safety; a zeroed
+    // struct keeps the portrayed name.
+    preferred_language: [4]u8,
 };
 
 /// The tri-state `soundings` field as the engine's optional bool.
@@ -2342,6 +2355,7 @@ fn marinerFromC(cm: *const CMariner) mariner.Settings {
         .sounding_size_scale = if (cm.sounding_size_scale > 0) cm.sounding_size_scale else 1.0,
         .device_scale = if (cm.device_scale > 0) cm.device_scale else 1.0,
         .chart_over_image = cm.chart_over_image,
+        .preferred_language = std.mem.sliceTo(&cm.preferred_language, 0),
         .viewing_groups_off = if (cm.viewing_groups_off != null and cm.viewing_groups_off_len > 0)
             cm.viewing_groups_off[0..cm.viewing_groups_off_len]
         else
@@ -2526,6 +2540,7 @@ export fn tile57_mariner_defaults(cm: ?*CMariner) callconv(.c) void {
         .sounding_size_scale = d.sounding_size_scale,
         .device_scale = d.device_scale,
         .chart_over_image = d.chart_over_image,
+        .preferred_language = langCode(d.preferred_language),
     };
 }
 

src/chart.zig

@@ -230,6 +230,7 @@ const CellBackend = struct {
     portrayal_plain: ?[]const ?[]const u8 = null, // PlainBoundaries variant (areas)
     portrayal_simplified: ?[]const ?[]const u8 = null, // SimplifiedSymbols variant (points)
     portrayal_lights: ?[]const ?[]const u8 = null, // FullLightLines variant (sectored lights)
+    portrayal_national: []const scene.LangStreams = &.{}, // one pass per national language
     portray_arena: ?*std.heap.ArenaAllocator = null,
     coverage: []const []const []const s57.LonLat = &.{}, // M_COVR (in portray_arena)
     cscl: i32 = 0, // compilation scale (DSPM CSCL, 1:N)
@@ -267,6 +268,7 @@ fn cellRef(cb: *CellBackend) scene.CellRef {
         .portrayal_plain = cb.portrayal_plain,
         .portrayal_simplified = cb.portrayal_simplified,
         .portrayal_lights = cb.portrayal_lights,
+        .portrayal_national = cb.portrayal_national,
         .geo = cb.geo,
         .geo_world = cb.geo_world,
         .feat_bbox = cb.feat_bbox,
@@ -290,6 +292,7 @@ const LazyCell = struct {
     portrayal_plain: ?[]const ?[]const u8 = null,
     portrayal_simplified: ?[]const ?[]const u8 = null,
     portrayal_lights: ?[]const ?[]const u8 = null,
+    portrayal_national: []const scene.LangStreams = &.{},
     arena: ?*std.heap.ArenaAllocator = null,
     tick: u64 = 0, // LRU: last tile that used this cell
     // M_COVR(CATCOV=1) coverage polygons, assembled once from `cell` for best-band
@@ -587,6 +590,14 @@ fn parseAnyCell(base: []const u8, updates: []const []const u8) ?CellLoad {
 
 /// Portray a cell three ways, using the native adapted set (S-101) when present,
 /// else the S-57 adapter.
+/// The portrayal's national passes as the scene's own type. The two modules
+/// state the same pair, and scene has no dependency on portray.
+fn nationalPasses(a: std.mem.Allocator, passes: []const portray.LangStreams) []const scene.LangStreams {
+    const out = a.alloc(scene.LangStreams, passes.len) catch return &.{};
+    for (passes, out) |p, *o| o.* = .{ .lang = p.lang, .streams = p.streams };
+    return out;
+}
+
 fn portrayVariantsAny(arena: std.mem.Allocator, cell: *const s57.Cell, adapted: ?[]const s101.adapter.Adapted, dir: []const u8) !portray.CellPortrayal {
     if (adapted) |ad| return portray.portrayCellVariantsAdapted(arena, cell, ad, dir);
     return portray.portrayCellVariants(arena, cell, dir);
@@ -610,6 +621,7 @@ fn lazyEnsureLoaded(ls: *LazySource, lc: *LazyCell) void {
             lc.portrayal_plain = cp.plain;
             lc.portrayal_simplified = cp.simplified;
             lc.portrayal_lights = cp.lights;
+            lc.portrayal_national = nationalPasses(p.allocator(), cp.national);
             lc.arena = p;
         } else |_| {
             p.deinit();
@@ -639,6 +651,7 @@ fn lazyUnload(lc: *LazyCell) void {
     lc.portrayal_plain = null;
     lc.portrayal_simplified = null;
     lc.portrayal_lights = null;
+    lc.portrayal_national = &.{};
     if (lc.arena) |p| {
         p.deinit();
         gpa.destroy(p);
@@ -780,6 +793,7 @@ fn buildCellBackend(base: []const u8, updates: []const []const u8, dir: []const
         cb.portrayal_plain = cp.plain;
         cb.portrayal_simplified = cp.simplified;
         cb.portrayal_lights = cp.lights;
+        cb.portrayal_national = nationalPasses(pa.allocator(), cp.national);
     } else |_| {}
     // Assemble geometry + its projection + per-feature bboxes ONCE (the baker's
     // per-cell caches) so live per-view rendering reuses them across the view's tiles
@@ -3104,6 +3118,7 @@ pub const Chart = struct {
                     .portrayal_plain = cb.portrayal_plain,
                     .portrayal_simplified = cb.portrayal_simplified,
                     .portrayal_lights = cb.portrayal_lights,
+                    .portrayal_national = cb.portrayal_national,
                 }};
                 return scene.generateView(&ps, a, gpa, &one, lon, lat, zoom, self.pick_attrs) catch error.TileGen;
             },
@@ -3366,6 +3381,7 @@ pub const Chart = struct {
                     .portrayal_plain = cb2.portrayal_plain,
                     .portrayal_simplified = cb2.portrayal_simplified,
                     .portrayal_lights = cb2.portrayal_lights,
+                    .portrayal_national = cb2.portrayal_national,
                     .geo = cb2.geo,
                     .geo_world = cb2.geo_world,
                     .feat_bbox = cb2.feat_bbox,
@@ -3528,6 +3544,7 @@ pub const Chart = struct {
                         .portrayal_plain = cb2.portrayal_plain,
                         .portrayal_simplified = cb2.portrayal_simplified,
                         .portrayal_lights = cb2.portrayal_lights,
+                        .portrayal_national = cb2.portrayal_national,
                     }};
                     scene.appendTile(surf, a, &one, z, qt.tx, qt.ty, self.pick_attrs) catch continue;
                 },
@@ -3581,6 +3598,7 @@ pub const Chart = struct {
                     .portrayal_plain = cb.portrayal_plain,
                     .portrayal_simplified = cb.portrayal_simplified,
                     .portrayal_lights = cb.portrayal_lights,
+                    .portrayal_national = cb.portrayal_national,
                 }};
                 return scene.generateView(&as, a, gpa, &one, lon, lat, zoom, self.pick_attrs) catch error.TileGen;
             },
@@ -4156,6 +4174,7 @@ const BakeWork = struct {
         var portrayal_plain: ?[]const ?[]const u8 = null;
         var portrayal_simplified: ?[]const ?[]const u8 = null;
         var portrayal_lights: ?[]const ?[]const u8 = null;
+        var portrayal_national: []const scene.LangStreams = &.{};
         var geo: ?scene.GeoParts = null;
         var geo_world: ?scene.GeoWorld = null;
         var feat_bbox: ?[]const ?[4]f64 = null;
@@ -4167,6 +4186,7 @@ const BakeWork = struct {
                 portrayal_plain = cp.plain;
                 portrayal_simplified = cp.simplified;
                 portrayal_lights = cp.lights;
+                portrayal_national = nationalPasses(p.allocator(), cp.national);
             } else |_| {}
             // Build the geometry cache for EVERY cell, unconditionally.
             // `build_geo` (cacheGeoForBand) gated it to the finer bands, but coarse cells are
@@ -4205,7 +4225,7 @@ const BakeWork = struct {
         // Sector-figure reach (exact, from the portrayal streams): buildTileMap
         // addresses the neighbouring tiles the cell's light legs/arcs cross.
         const lr = scene.collectLightReach(&cell, portrayal);
-        c.outs[i] = .{ .cell = cell, .portrayal = portrayal, .portrayal_plain = portrayal_plain, .portrayal_simplified = portrayal_simplified, .portrayal_lights = portrayal_lights, .geo = geo, .geo_world = geo_world, .feat_bbox = feat_bbox, .bounds = b, .cscl = cscl, .coverage = coverage, .scamins = scamins, .light_bbox = lr.bbox, .light_range_m = lr.range_m };
+        c.outs[i] = .{ .cell = cell, .portrayal = portrayal, .portrayal_plain = portrayal_plain, .portrayal_simplified = portrayal_simplified, .portrayal_lights = portrayal_lights, .portrayal_national = portrayal_national, .geo = geo, .geo_world = geo_world, .feat_bbox = feat_bbox, .bounds = b, .cscl = cscl, .coverage = coverage, .scamins = scamins, .light_bbox = lr.bbox, .light_range_m = lr.range_m };
         c.arenas[i] = pa;
     }
 };

src/portray/lua_shim.c

@@ -140,6 +140,10 @@ typedef struct tg_portray_ctx {
     double shallow_contour;
     double deep_contour;
     double safety_height;
+    /* ISO 639-2 code the rules match featureName.language against. The
+     * catalogue's GetFeatureName returns the entry whose language equals this,
+     * and falls back to the nameUsage 1 entry when none does. */
+    const char *preferred_language;
 } tg_portray_ctx;
 
 static const tg_portray_ctx tg_default_ctx = {
@@ -166,6 +170,8 @@ static void tg_set_ctx_globals(lua_State *L, const tg_portray_ctx *ctx) {
     TG_SET_REAL("SHALLOW_CONTOUR", ctx->shallow_contour);
     TG_SET_REAL("DEEP_CONTOUR", ctx->deep_contour);
     TG_SET_REAL("SAFETY_HEIGHT", ctx->safety_height);
+    lua_pushstring(L, ctx->preferred_language ? ctx->preferred_language : "eng");
+    lua_setglobal(L, "PREFERRED_LANGUAGE");
 #undef TG_SET_BOOL
 #undef TG_SET_REAL
 }
@@ -583,7 +589,7 @@ int tile57_diag_portray_demo(const char *dir) {
         "cp('ShallowWaterDangers','boolean','false'); cp('SafetyContour','real','30')\n"
         "cp('SafetyDepth','real','30'); cp('ShallowContour','real','2')\n"
         "cp('DeepContour','real','30'); cp('SafetyHeight','real','0')\n"
-        "cp('PreferredLanguage','text','eng')\n"
+        "cp('PreferredLanguage','text', PREFERRED_LANGUAGE)\n"
         "PortrayalInitializeContextParameters(cps)\n"
         "local out={}\n"
         "local ctx=portrayalContext.ContextParameters\n"
@@ -1107,7 +1113,7 @@ int tg_portray_run(const char *dir, size_t dir_len, const tg_portray_ctx *ctx) {
         "cp('ShallowWaterDangers','boolean', b(SHALLOW_WATER_DANGERS)); cp('SafetyContour','real', SAFETY_CONTOUR)\n"
         "cp('SafetyDepth','real', SAFETY_DEPTH); cp('ShallowContour','real', SHALLOW_CONTOUR)\n"
         "cp('DeepContour','real', DEEP_CONTOUR); cp('SafetyHeight','real', SAFETY_HEIGHT)\n"
-        "cp('PreferredLanguage','text','eng')\n"
+        "cp('PreferredLanguage','text', PREFERRED_LANGUAGE)\n"
         "PortrayalInitializeContextParameters(cps)\n"
         // Drive portrayal through the reference S-100 Part 9a entry point exactly as
         // the catalogue intends. HostPortrayalEmit is the framework's per-feature