Add support for parsing MLT-format vector tile sources (#3246)

Co-authored-by: Bart Louwers <bart@emeel.net>
Co-authored-by: Bart Louwers <bart.louwers@gmail.com>

.gitmodules

@@ -100,6 +100,10 @@
 [submodule "vendor/filesystem"]
 	path = vendor/filesystem
 	url = https://github.com/gulrak/filesystem.git
+[submodule "vendor/maplibre-tile-spec"]
+	path = vendor/maplibre-tile-spec
+	url = https://github.com/maplibre/maplibre-tile-spec.git
+	branch = cpp
 [submodule "vendor/kdbush.hpp"]
 	path = vendor/kdbush.hpp
 	url = https://github.com/mourner/kdbush.hpp.git

BUILD.bazel

@@ -144,6 +144,7 @@ cc_library(
         "//vendor:eternal",
         "//vendor:expected-lite",
         "//vendor:maplibre-native-base",
+        "//vendor/maplibre-tile-spec/cpp:mlt_cpp",
         "//vendor:parsedate",
         "//vendor:pmtiles",
         "//vendor:polylabel",

CMakeLists.txt

@@ -302,9 +302,9 @@ list(APPEND INCLUDE_FILES
     ${PROJECT_SOURCE_DIR}/include/mbgl/style/conversion/light.hpp
     ${PROJECT_SOURCE_DIR}/include/mbgl/style/conversion/position.hpp
     ${PROJECT_SOURCE_DIR}/include/mbgl/style/conversion/property_value.hpp
-    ${PROJECT_SOURCE_DIR}/include/mbgl/style/conversion/raster_dem_options.hpp
     ${PROJECT_SOURCE_DIR}/include/mbgl/style/conversion/rotation.hpp
     ${PROJECT_SOURCE_DIR}/include/mbgl/style/conversion/source.hpp
+    ${PROJECT_SOURCE_DIR}/include/mbgl/style/conversion/source_options.hpp
     ${PROJECT_SOURCE_DIR}/include/mbgl/style/conversion/tileset.hpp
     ${PROJECT_SOURCE_DIR}/include/mbgl/style/conversion/transition_options.hpp
     ${PROJECT_SOURCE_DIR}/include/mbgl/style/expression/assertion.hpp
@@ -676,9 +676,9 @@ list(APPEND SRC_FILES
     ${PROJECT_SOURCE_DIR}/src/mbgl/style/conversion/light.cpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/style/conversion/position.cpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/style/conversion/property_value.cpp
-    ${PROJECT_SOURCE_DIR}/src/mbgl/style/conversion/raster_dem_options.cpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/style/conversion/rotation.cpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/style/conversion/source.cpp
+    ${PROJECT_SOURCE_DIR}/src/mbgl/style/conversion/source_options.cpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/style/conversion/stringify.hpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/style/conversion/tileset.cpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/style/conversion/transition_options.cpp
@@ -879,10 +879,15 @@ list(APPEND SRC_FILES
     ${PROJECT_SOURCE_DIR}/src/mbgl/tile/tile_operation.cpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_tile.cpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_tile.hpp
-    ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_tile_data.cpp
-    ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_tile_data.hpp
+    ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_mlt_tile.cpp
+    ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_mlt_tile.hpp
+    ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_mlt_tile_data.cpp
+    ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_mlt_tile_data.hpp
+    ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_mvt_tile.cpp
+    ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_mvt_tile.hpp
+    ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_mvt_tile_data.cpp
+    ${PROJECT_SOURCE_DIR}/src/mbgl/tile/vector_mvt_tile_data.hpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/util/action_journal.cpp
-    ${PROJECT_SOURCE_DIR}/src/mbgl/util/action_journal_impl.hpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/util/action_journal_impl.cpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/util/camera.cpp
     ${PROJECT_SOURCE_DIR}/src/mbgl/util/bounding_volumes.hpp
@@ -1553,6 +1558,7 @@ include(${PROJECT_SOURCE_DIR}/vendor/unordered_dense.cmake)
 include(${PROJECT_SOURCE_DIR}/vendor/vector-tile.cmake)
 include(${PROJECT_SOURCE_DIR}/vendor/wagyu.cmake)
 include(${PROJECT_SOURCE_DIR}/vendor/metal-cpp.cmake)
+include(${PROJECT_SOURCE_DIR}/vendor/maplibre-tile-spec.cmake)
 include(${PROJECT_SOURCE_DIR}/vendor/supercluster.cmake)
 include(${PROJECT_SOURCE_DIR}/vendor/expected-lite.cmake)
 include(${PROJECT_SOURCE_DIR}/vendor/kdbush.cmake)
@@ -1581,6 +1587,7 @@ target_link_libraries(
         mbgl-vendor-unique_resource
         mbgl-vendor-vector-tile
         mbgl-vendor-wagyu
+	    mlt-cpp
         $<$<BOOL:${MLN_WITH_METAL}>:mbgl-vendor-metal-cpp>
         $<IF:$<BOOL:${MLN_USE_RUST}>,mbgl-rustutils,mbgl-vendor-csscolorparser>
         $<$<BOOL:${MLN_TEXT_SHAPING_HARFBUZZ}>:mbgl-freetype>
@@ -1614,6 +1621,8 @@ set(EXPORT_TARGETS
     mbgl-vendor-boost
     mbgl-vendor-earcut.hpp
     mbgl-vendor-eternal
+    mbgl-vendor-filesystem
+    mbgl-vendor-metal-cpp
     mbgl-vendor-rapidjson
     mbgl-vendor-parsedate
     mbgl-vendor-pmtiles
@@ -1622,8 +1631,7 @@ set(EXPORT_TARGETS
     mbgl-vendor-unique_resource
     mbgl-vendor-vector-tile
     mbgl-vendor-wagyu
-    mbgl-vendor-metal-cpp
-    mbgl-vendor-filesystem
+    mlt-cpp
     unordered_dense
 )
 

bazel/core.bzl

@@ -336,9 +336,9 @@ MLN_CORE_SOURCE = [
     "src/mbgl/style/conversion/light.cpp",
     "src/mbgl/style/conversion/position.cpp",
     "src/mbgl/style/conversion/property_value.cpp",
-    "src/mbgl/style/conversion/raster_dem_options.cpp",
     "src/mbgl/style/conversion/rotation.cpp",
     "src/mbgl/style/conversion/source.cpp",
+    "src/mbgl/style/conversion/source_options.cpp",
     "src/mbgl/style/conversion/stringify.hpp",
     "src/mbgl/style/conversion/tileset.cpp",
     "src/mbgl/style/conversion/transition_options.cpp",
@@ -514,8 +514,14 @@ MLN_CORE_SOURCE = [
     "src/mbgl/tile/tile_operation.cpp",
     "src/mbgl/tile/vector_tile.cpp",
     "src/mbgl/tile/vector_tile.hpp",
-    "src/mbgl/tile/vector_tile_data.cpp",
-    "src/mbgl/tile/vector_tile_data.hpp",
+    "src/mbgl/tile/vector_mlt_tile.cpp",
+    "src/mbgl/tile/vector_mlt_tile.hpp",
+    "src/mbgl/tile/vector_mlt_tile_data.cpp",
+    "src/mbgl/tile/vector_mlt_tile_data.hpp",
+    "src/mbgl/tile/vector_mvt_tile.cpp",
+    "src/mbgl/tile/vector_mvt_tile.hpp",
+    "src/mbgl/tile/vector_mvt_tile_data.cpp",
+    "src/mbgl/tile/vector_mvt_tile_data.hpp",
     "src/mbgl/util/action_journal.cpp",
     "src/mbgl/util/action_journal_impl.hpp",
     "src/mbgl/util/action_journal_impl.cpp",
@@ -696,9 +702,9 @@ MLN_CORE_HEADERS = [
     "include/mbgl/style/conversion/light.hpp",
     "include/mbgl/style/conversion/position.hpp",
     "include/mbgl/style/conversion/property_value.hpp",
-    "include/mbgl/style/conversion/raster_dem_options.hpp",
     "include/mbgl/style/conversion/rotation.hpp",
     "include/mbgl/style/conversion/source.hpp",
+    "include/mbgl/style/conversion/source_options.hpp",
     "include/mbgl/style/conversion/tileset.hpp",
     "include/mbgl/style/conversion/transition_options.hpp",
     "include/mbgl/style/conversion_impl.hpp",

benchmark/parse/vector_tile.benchmark.cpp

@@ -1,6 +1,6 @@
 #include <benchmark/benchmark.h>
 
-#include <mbgl/tile/vector_tile_data.hpp>
+#include <mbgl/tile/vector_mvt_tile_data.hpp>
 #include <mbgl/util/io.hpp>
 
 using namespace mbgl;
@@ -11,7 +11,7 @@ static void Parse_VectorTile(benchmark::State& state) {
 
     while (state.KeepRunning()) {
         std::size_t length = 0;
-        VectorTileData tile(data);
+        VectorMVTTileData tile(data);
         for (const auto& name : tile.layerNames()) {
             if (auto layer = tile.getLayer(name)) {
                 const std::size_t count = layer->featureCount();

bin/cache.cpp

@@ -7,14 +7,13 @@
 #include <args.hxx>
 #include <mapbox/io/io.hpp>
 
-#include <fstream>
 #include <iostream>
 #include <memory>
 #include <string>
 #include <unordered_map>
 
 int main(int argc, char* argv[]) {
-    args::ArgumentParser p("Mapbox GL cache tool", "");
+    args::ArgumentParser p("MapLibre cache tool", "");
     args::HelpFlag helpFlag(p, "help", "Display this help menu", {'h'});
 
     args::ValueFlag<std::string> urlValue(p, "URL", "Resource URL (required)", {'u'}, args::Options::Required);
@@ -35,7 +34,7 @@ int main(int argc, char* argv[]) {
                                                                   {"tile", mbgl::Resource::Tile}};
 
     std::string typeHelp("One of the following (required):");
-    for (auto key : typeMap) {
+    for (const auto& key : typeMap) {
         typeHelp += " " + key.first;
     }
 
@@ -53,18 +52,18 @@ int main(int argc, char* argv[]) {
         std::cout << p;
         exit(0);
     } catch (const args::ParseError& e) {
-        std::cerr << e.what() << std::endl;
+        std::cerr << e.what() << '\n';
         std::cerr << p;
         exit(1);
     } catch (const args::ValidationError& e) {
-        std::cerr << e.what() << std::endl;
+        std::cerr << e.what() << '\n';
         std::cerr << p;
         exit(2);
     }
 
     auto file = mapbox::base::io::readFile(args::get(dataValue));
     if (!file) {
-        std::cerr << file.error() << std::endl;
+        std::cerr << file.error() << '\n';
         exit(3);
     }
 
@@ -78,15 +77,15 @@ int main(int argc, char* argv[]) {
 
     if (args::get(typeFlag) == mbgl::Resource::Tile) {
         if (!xValueFlag || !yValueFlag || !zValueFlag) {
-            std::cerr << "Error: -x, -y and -z must be provided for tiles" << std::endl;
+            std::cerr << "Error: -x, -y and -z must be provided for tiles" << '\n';
             exit(1);
         }
 
-        resource.tileData = {{args::get(urlValue),
-                              1,
-                              args::get(xValueFlag),
-                              args::get(yValueFlag),
-                              static_cast<int8_t>(args::get(zValueFlag))}};
+        resource.tileData = {{.urlTemplate = args::get(urlValue),
+                              .pixelRatio = 1,
+                              .x = args::get(xValueFlag),
+                              .y = args::get(yValueFlag),
+                              .z = static_cast<int8_t>(args::get(zValueFlag))}};
     }
 
     mbgl::util::RunLoop loop;

include/mbgl/style/conversion/source_options.hpp

@@ -8,8 +8,8 @@ namespace style {
 namespace conversion {
 
 template <>
-struct Converter<RasterDEMOptions> {
-    std::optional<RasterDEMOptions> operator()(const Convertible& value, Error& error) const;
+struct Converter<SourceOptions> {
+    std::optional<SourceOptions> operator()(const Convertible& value, Error& error) const;
 };
 
 } // namespace conversion

include/mbgl/style/sources/raster_dem_source.hpp

@@ -7,8 +7,9 @@
 namespace mbgl {
 namespace style {
 
-struct RasterDEMOptions {
-    std::optional<Tileset::DEMEncoding> encoding = std::nullopt;
+struct SourceOptions {
+    std::optional<Tileset::RasterEncoding> rasterEncoding = std::nullopt;
+    std::optional<Tileset::VectorEncoding> vectorEncoding = std::nullopt;
 };
 
 // NOTE: Any derived class must invalidate `weakFactory` in the destructor
@@ -17,7 +18,7 @@ public:
     RasterDEMSource(std::string id,
                     variant<std::string, Tileset> urlOrTileset,
                     uint16_t tileSize,
-                    std::optional<RasterDEMOptions> options = std::nullopt);
+                    std::optional<SourceOptions> options = std::nullopt);
     ~RasterDEMSource() override;
     bool supportsLayerType(const mbgl::style::LayerTypeInfo*) const override;
 
@@ -25,7 +26,7 @@ protected:
     void setTilesetOverrides(Tileset& tileset) override;
 
 private:
-    std::optional<RasterDEMOptions> options;
+    std::optional<SourceOptions> options;
 };
 
 template <>

include/mbgl/style/sources/vector_source.hpp

@@ -16,7 +16,8 @@ public:
     VectorSource(std::string id,
                  variant<std::string, Tileset> urlOrTileset,
                  std::optional<float> maxZoom = std::nullopt,
-                 std::optional<float> minZoom = std::nullopt);
+                 std::optional<float> minZoom = std::nullopt,
+                 Tileset::VectorEncoding encoding = Tileset::VectorEncoding::Mapbox);
 
     void setTilesetOverrides(Tileset& tileset) override;
 
@@ -30,11 +31,14 @@ public:
 
     bool supportsLayerType(const mbgl::style::LayerTypeInfo*) const override;
 
+    Tileset::VectorEncoding getEncoding() const noexcept { return encoding; }
+
     mapbox::base::WeakPtr<Source> makeWeakPtr() override { return weakFactory.makeWeakPtr(); }
 
 private:
     std::optional<float> maxZoom;
     std::optional<float> minZoom;
+    Tileset::VectorEncoding encoding;
     mapbox::base::WeakPtrFactory<Source> weakFactory{this}; // Must remain last
 };
 

include/mbgl/util/tileset.hpp

@@ -18,38 +18,40 @@ public:
         XYZ,
         TMS
     };
-    enum class DEMEncoding : bool {
-        Mapbox,
-        Terrarium
+    enum class RasterEncoding : std::uint8_t {
+        Mapbox,    // Mapbox DEM
+        Terrarium, // Terrarium DEM
+    };
+    enum class VectorEncoding : std::uint8_t {
+        Mapbox, // Mapbox Vector Tiles (MVT)
+        MLT,    // MapLibre Tiles
     };
 
     std::vector<std::string> tiles;
     Range<uint8_t> zoomRange;
     std::string attribution;
     Scheme scheme;
-    // DEMEncoding is not supported by the TileJSON spec
-    DEMEncoding encoding;
+    std::optional<RasterEncoding> rasterEncoding;
+    std::optional<VectorEncoding> vectorEncoding;
     std::optional<LatLngBounds> bounds;
 
     Tileset(std::vector<std::string> tiles_ = std::vector<std::string>(),
             Range<uint8_t> zoomRange_ = {0, util::DEFAULT_MAX_ZOOM},
             std::string attribution_ = {},
             Scheme scheme_ = Scheme::XYZ,
-            DEMEncoding encoding_ = DEMEncoding::Mapbox)
+            std::optional<RasterEncoding> rasterEncoding_ = std::nullopt,
+            std::optional<VectorEncoding> encoding_ = std::nullopt)
         : tiles(std::move(tiles_)),
           zoomRange(zoomRange_),
           attribution(std::move(attribution_)),
           scheme(scheme_),
-          encoding(encoding_) {};
+          rasterEncoding(rasterEncoding_),
+          vectorEncoding(encoding_) {}
 
     // TileJSON also includes center and zoom but they are not used by mbgl.
 
-    friend bool operator==(const Tileset& lhs, const Tileset& rhs) noexcept {
-        return std::tie(lhs.tiles, lhs.zoomRange, lhs.attribution, lhs.scheme, lhs.bounds) ==
-               std::tie(rhs.tiles, rhs.zoomRange, rhs.attribution, rhs.scheme, rhs.bounds);
-    }
-
-    friend bool operator!=(const Tileset& lhs, const Tileset& rhs) noexcept { return !(lhs == rhs); }
+    bool operator==(const Tileset&) const = default;
+    bool operator!=(const Tileset&) const = default;
 };
 
 } // namespace mbgl

metrics/integration/render-tests/extent/1024-symbol/style.json

@@ -2,7 +2,13 @@
   "version": 8,
   "metadata": {
     "test": {
-      "allowed": 0.003
+      "allowed": 0.003,
+      "source-replace": [
+        {
+          "replace": "maplibre",
+          "with": "mlt"
+        }
+      ]
     }
   },
   "center": [
@@ -19,6 +25,14 @@
       "tiles": [
         "local://tiles/extent1024-14-8802-5374.mvt"
       ]
+    },
+    "mlt": {
+      "type": "vector",
+      "maxzoom": 14,
+      "tiles": [
+        "local://tiles/extent1024-14-8802-5374.mlt"
+      ],
+      "encoding": "mlt"
     }
   },
   "layers": [

metrics/integration/render-tests/fill-pattern/wrapping-with-interpolation/style.json

@@ -1,7 +1,14 @@
 {
   "version": 8,
   "metadata": {
-    "test": {}
+    "test": {
+      "source-replace": [
+        {
+          "replace": "maplibre",
+          "with": "mlt"
+        }
+      ]
+    }
   },
   "zoom": 0.99,
   "center": [
@@ -15,6 +22,14 @@
       "tiles": [
         "local://tiles/{z}-{x}-{y}.mvt"
       ]
+    },
+    "mlt": {
+      "type": "vector",
+      "maxzoom": 14,
+      "tiles": [
+        "local://tiles/{z}-{x}-{y}.mlt"
+      ],
+      "encoding": "mlt"
     }
   },
   "sprite": "local://sprites/solid-black",

metrics/integration/render-tests/icon-visibility/visible/style.json

@@ -2,7 +2,11 @@
   "version": 8,
   "metadata": {
     "test": {
-      "height": 256
+      "height": 256,
+      "source-replace": [{
+          "replace": "maplibre",
+          "with": "mlt"
+      }]
     }
   },
   "center": [
@@ -17,6 +21,14 @@
       "tiles": [
         "local://tiles/{z}-{x}-{y}.mvt"
       ]
+    },
+    "mlt": {
+      "type": "vector",
+      "maxzoom": 14,
+      "tiles": [
+        "local://tiles/{z}-{x}-{y}.mlt"
+      ],
+      "encoding": "mlt"
     }
   },
   "sprite": "local://sprites/sprite",

metrics/integration/render-tests/text-pitch-alignment/viewport-overzoomed-single-glyph/style.json

@@ -1,5 +1,15 @@
 {
   "version": 8,
+  "metadata": {
+    "test": {
+      "source-replace": [
+        {
+          "replace": "maplibre",
+          "with": "mlt"
+        }
+      ]
+    }
+  },
   "center": [
     -118.28162,
     33.86852
@@ -14,6 +24,14 @@
       "tiles": [
         "local://tiles/mapbox.mapbox-streets-v7/16-11235-26208.mvt"
       ]
+    },
+    "mlt": {
+      "type": "vector",
+      "maxzoom": 16,
+      "tiles": [
+        "local://tiles/mapbox.mapbox-streets-v7/16-11235-26208.mlt"
+      ],
+      "encoding": "mlt"
     }
   },
   "glyphs": "local://glyphs/{fontstack}/{range}.pbf",

metrics/integration/render-tests/tms/tms/style.json

@@ -1,7 +1,14 @@
 {
   "version": 8,
   "metadata": {
-    "test": {}
+    "test": {
+      "source-replace": [
+        {
+          "replace": "maplibre",
+          "with": "mlt"
+        }
+      ]
+    }
   },
   "zoom": 2,
   "sources": {
@@ -12,6 +19,15 @@
       "tiles": [
         "local://tiles/{z}-{x}-{y}.tms.mvt"
       ]
+    },
+    "mlt": {
+      "type": "vector",
+      "maxzoom": 14,
+      "scheme": "tms",
+      "tiles": [
+        "local://tiles/{z}-{x}-{y}.tms.mlt"
+      ],
+      "encoding": "mlt"
     }
   },
   "layers": [

platform/darwin/src/MLNRasterDEMSource.h

@@ -10,11 +10,30 @@
  The default value for this option is ``MLNDEMEncoding/MLNDEMEncodingMapbox``.
 
  This option cannot be represented in a TileJSON or style JSON file. It is used
- with the ``MLNRasterDEMSource`` class and is ignored when creating an
+ with the ``MLNRasterDEMSource`` class and is ignored when creating a
  ``MLNRasterTileSource`` or ``MLNRasterTileSource`` object.
  */
 FOUNDATION_EXTERN MLN_EXPORT const MLNTileSourceOption MLNTileSourceOptionDEMEncoding;
 
+/**
+ The encoding formula used to generate the raster tileset
+*/
+
+typedef NS_ENUM(NSUInteger, MLNDEMEncoding) {
+
+  /**
+     Raster tiles generated with the [Mapbox encoding
+     formula](https://docs.mapbox.com/help/troubleshooting/access-elevation-data/#mapbox-terrain-rgb)
+  */
+  MLNDEMEncodingMapbox = 0,
+
+  /**
+   Raster tiles generated with the [Mapzen Terrarium encoding
+   formula](https://aws.amazon.com/public-datasets/terrain/).
+  */
+  MLNDEMEncodingTerrarium = 1,
+};
+
 /**
  ``MLNRasterDEMSource`` is a map content source that supplies rasterized
  <a href="https://en.wikipedia.org/wiki/Digital_elevation_model">digital elevation model</a>

platform/darwin/src/MLNRasterDEMSource.mm

@@ -5,6 +5,8 @@
 
 #import <mbgl/style/sources/raster_dem_source.hpp>
 
+const MLNTileSourceOption MLNTileSourceOptionDEMEncoding = @"MLNTileSourceOptionDEMEncoding";
+
 @implementation MLNRasterDEMSource
 
 - (std::unique_ptr<mbgl::style::RasterSource>)pendingSourceWithIdentifier:(NSString *)identifier urlOrTileset:(mbgl::variant<std::string, mbgl::Tileset>)urlOrTileset tileSize:(uint16_t)tileSize {

platform/darwin/src/MLNTileSource.h

@@ -142,25 +142,6 @@ typedef NS_ENUM(NSUInteger, MLNTileCoordinateSystem) {
   MLNTileCoordinateSystemTMS
 };
 
-/**
- The encoding formula used to generate the raster-dem tileset
-*/
-
-typedef NS_ENUM(NSUInteger, MLNDEMEncoding) {
-
-  /**
-   Raster tiles generated with the [Mapbox encoding
-   formula](https://docs.mapbox.com/help/troubleshooting/access-elevation-data/#mapbox-terrain-rgb).
-  */
-  MLNDEMEncodingMapbox = 0,
-
-  /**
-   Raster tiles generated with the [Mapzen Terrarium encoding
-   formula](https://aws.amazon.com/public-datasets/terrain/).
-  */
-  MLNDEMEncodingTerrarium
-};
-
 /**
  ``MLNTileSource`` is a map content source that supplies map tiles to be shown on
  the map. The location of and metadata about the tiles are defined either by an

platform/darwin/src/MLNTileSource.mm

@@ -3,6 +3,7 @@
 #import "MLNAttributionInfo_Private.h"
 #import "MLNGeometry_Private.h"
 #import "MLNRasterDEMSource.h"
+#import "MLNVectorTileSource.h"
 #import "NSString+MLNAdditions.h"
 #import "NSValue+MLNAdditions.h"
 
@@ -20,7 +21,6 @@ const MLNTileSourceOption MLNTileSourceOptionCoordinateBounds = @"MLNTileSourceO
 const MLNTileSourceOption MLNTileSourceOptionAttributionHTMLString = @"MLNTileSourceOptionAttributionHTMLString";
 const MLNTileSourceOption MLNTileSourceOptionAttributionInfos = @"MLNTileSourceOptionAttributionInfos";
 const MLNTileSourceOption MLNTileSourceOptionTileCoordinateSystem = @"MLNTileSourceOptionTileCoordinateSystem";
-const MLNTileSourceOption MLNTileSourceOptionDEMEncoding = @"MLNTileSourceOptionDEMEncoding";
 
 @implementation MLNTileSource
 
@@ -131,19 +131,38 @@ mbgl::Tileset MLNTileSetFromTileURLTemplates(NSArray<NSString *> *tileURLTemplat
         }
     }
 
-    if (NSNumber *demEncodingNumber = options[MLNTileSourceOptionDEMEncoding]) {
-        if (![demEncodingNumber isKindOfClass:[NSValue class]]) {
+    NSNumber *encodingNumber = options[MLNTileSourceOptionDEMEncoding];
+    if (encodingNumber) {
+        if (![encodingNumber isKindOfClass:[NSValue class]]) {
             [NSException raise:NSInvalidArgumentException
                         format:@"MLNTileSourceOptionDEMEncoding must be set to an NSValue or NSNumber."];
         }
-        MLNDEMEncoding demEncoding;
-        [demEncodingNumber getValue:&demEncoding];
-        switch (demEncoding) {
+        MLNDEMEncoding encoding;
+        [encodingNumber getValue:&encoding];
+        switch (encoding) {
             case MLNDEMEncodingMapbox:
-                tileSet.encoding = mbgl::Tileset::DEMEncoding::Mapbox;
+                tileSet.rasterEncoding = mbgl::Tileset::RasterEncoding::Mapbox;
                 break;
             case MLNDEMEncodingTerrarium:
-                tileSet.encoding = mbgl::Tileset::DEMEncoding::Terrarium;
+                tileSet.rasterEncoding = mbgl::Tileset::RasterEncoding::Terrarium;
+                break;
+        }
+    }
+
+    encodingNumber = options[MLNVectorTileSourceOptionEncoding];
+    if (encodingNumber) {
+        if (![encodingNumber isKindOfClass:[NSValue class]]) {
+            [NSException raise:NSInvalidArgumentException
+                        format:@"MLNTileSourceOptionVectorEncoding must be set to an NSValue or NSNumber."];
+        }
+        MLNVectorTileSourceEncoding encoding;
+        [encodingNumber getValue:&encoding];
+        switch (encoding) {
+            case MLNVectorTileSourceEncodingMapbox:
+                tileSet.vectorEncoding = mbgl::Tileset::VectorEncoding::Mapbox;
+                break;
+            case MLNVectorTileSourceEncodingMLT:
+                tileSet.vectorEncoding = mbgl::Tileset::VectorEncoding::MLT;
                 break;
         }
     }

platform/darwin/src/MLNVectorTileSource.h

@@ -4,6 +4,33 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
+/**
+ An `NSNumber` object containing an unsigned integer that specifies the encoding
+ formula for vector tilesets. The integer corresponds to one of the constants in
+ ``MLNVectorTileSourceEncoding``.
+
+ The default value for this option is
+ ``MLNVectorTileSourceEncoding/MLNVectorTileSourceEncodingMapbox``.
+ */
+FOUNDATION_EXTERN MLN_EXPORT const MLNTileSourceOption MLNVectorTileSourceOptionEncoding;
+
+/**
+ The encoding formula used to generate the raster-dem tileset
+*/
+
+typedef NS_ENUM(NSUInteger, MLNVectorTileSourceEncoding) {
+
+  /**
+     Vector tiles in [MVT format](https://github.com/mapbox/vector-tile-spec).
+  */
+  MLNVectorTileSourceEncodingMapbox = 0,
+
+  /**
+   Vector tiles in [MLT format](https://github.com/maplibre/maplibre-tile-spec).
+  */
+  MLNVectorTileSourceEncodingMLT = 1,
+};
+
 /**
  ``MLNVectorTileSource`` is a map content source that supplies tiled vector data
  in <a href="https://www.mapbox.com/vector-tiles/">Mapbox Vector Tile</a> format

platform/darwin/src/MLNVectorTileSource.mm

@@ -14,6 +14,8 @@
 #include <mbgl/style/sources/vector_source.hpp>
 #include <mbgl/renderer/renderer.hpp>
 
+const MLNTileSourceOption MLNVectorTileSourceOptionEncoding = @"MLNVectorTileSourceOptionEncoding";
+
 @interface MLNVectorTileSource ()
 
 @property (nonatomic, readonly) mbgl::style::VectorSource *rawSource;

platform/darwin/test/MLNTileSetTests.mm

@@ -1,6 +1,7 @@
 #import <XCTest/XCTest.h>
 
 #import <Mapbox.h>
+#import "MLNVectorTileSource.h"
 #import "MLNTileSource_Private.h"
 #import "MLNGeometry_Private.h"
 
@@ -12,9 +13,13 @@
 
 @implementation MLNTileSetTests
 
-- (void)testTileSetFromTileURLTemplates {
+namespace {
     // a tile set that provides an mbgl tile set
     NSArray *tileURLTemplates = @[@"tile.1", @"tile.2", @"tile.3"];
+
+}
+
+- (void)testTileSetFromTileURLTemplates {
     mbgl::Tileset tileSet = MLNTileSetFromTileURLTemplates(tileURLTemplates, nil);
 
     // has the correct URL templates
@@ -120,23 +125,61 @@
 
     // the scheme is reflected by the mbgl tileset
     XCTAssertEqual(tileSet.scheme, mbgl::Tileset::Scheme::TMS);
+}
 
-    // when the dem encoding is changed using an NSNumber
+- (void)testTileSetFromTileURLTemplatesRasterEncodings {
+    mbgl::Tileset tileSet;
+
+    // when the DEM encoding is changed using an NSNumber
     tileSet = MLNTileSetFromTileURLTemplates(tileURLTemplates, @{
         MLNTileSourceOptionDEMEncoding: @(MLNDEMEncodingTerrarium),
     });
 
     // the encoding is reflected by the mbgl tileset
-    XCTAssertEqual(tileSet.encoding, mbgl::Tileset::DEMEncoding::Terrarium);
+    XCTAssertEqual(tileSet.rasterEncoding, mbgl::Tileset::RasterEncoding::Terrarium);
+    XCTAssertFalse(tileSet.vectorEncoding);
 
-    // when the dem encoding is changed using an NSValue
+    // when the raster encoding is changed using an NSValue
     MLNDEMEncoding terrarium = MLNDEMEncodingTerrarium;
     tileSet = MLNTileSetFromTileURLTemplates(tileURLTemplates, @{
         MLNTileSourceOptionDEMEncoding: [NSValue value:&terrarium withObjCType:@encode(MLNDEMEncoding)],
     });
 
     // the encoding is reflected by the mbgl tileset
-    XCTAssertEqual(tileSet.encoding, mbgl::Tileset::DEMEncoding::Terrarium);
+    XCTAssertEqual(tileSet.rasterEncoding, mbgl::Tileset::RasterEncoding::Terrarium);
+    XCTAssertFalse(tileSet.vectorEncoding);
+}
+
+- (void)testTileSetFromTileURLTemplatesVectorEncodings {
+    mbgl::Tileset tileSet;
+
+    // when the raster encoding is changed using an NSNumber
+    tileSet = MLNTileSetFromTileURLTemplates(tileURLTemplates, @{
+        MLNVectorTileSourceOptionEncoding: @(MLNVectorTileSourceEncodingMapbox),
+    });
+
+    // the encoding is reflected by the mbgl tileset
+    XCTAssertEqual(tileSet.vectorEncoding, mbgl::Tileset::VectorEncoding::Mapbox);
+    XCTAssertFalse(tileSet.rasterEncoding);
+
+    // when the raster encoding is changed using an NSNumber
+    tileSet = MLNTileSetFromTileURLTemplates(tileURLTemplates, @{
+        MLNVectorTileSourceOptionEncoding: @(MLNVectorTileSourceEncodingMLT),
+    });
+
+    // the encoding is reflected by the mbgl tileset
+    XCTAssertEqual(tileSet.vectorEncoding, mbgl::Tileset::VectorEncoding::MLT);
+    XCTAssertFalse(tileSet.rasterEncoding);
+
+    // when the raster encoding is changed using an NSValue
+    MLNVectorTileSourceEncoding mlt = MLNVectorTileSourceEncodingMLT;
+    tileSet = MLNTileSetFromTileURLTemplates(tileURLTemplates, @{
+        MLNVectorTileSourceOptionEncoding: [NSValue value:&mlt withObjCType:@encode(MLNVectorTileSourceEncoding)],
+    });
+
+    // the encoding is reflected by the mbgl tileset
+    XCTAssertEqual(tileSet.vectorEncoding, mbgl::Tileset::VectorEncoding::MLT);
+    XCTAssertFalse(tileSet.rasterEncoding);
 }
 
 - (void)testInvalidTileSet {

platform/default/src/mbgl/storage/mbtiles_file_source.cpp

@@ -105,6 +105,11 @@ public:
         const auto format_ptr = values.find("format");
         const std::string format = (format_ptr == values.end()) ? "png" : format_ptr->second;
 
+        // Translate MIME type field to source encoding.
+        if (format == "mlt" || format == "application/vnd.maplibre-vector-tile") {
+            doc.AddMember("encoding", "mlt", allocator);
+        }
+
         if (format != "pbf" && !values.contains("scale")) {
             values["scale"] = "1";
         }

platform/default/src/mbgl/storage/pmtiles_file_source.cpp

@@ -47,6 +47,11 @@ std::string extract_url(const std::string& url) {
 }
 } // namespace
 
+// temporary, remove this when it's available in `pmtiles.hpp`
+namespace pmtiles {
+const uint8_t TILETYPE_MLT = 0x6;
+} // namespace pmtiles
+
 namespace mbgl {
 using namespace rapidjson;
 
@@ -305,6 +310,11 @@ private:
                         rapidjson::Value().SetString(std::string(util::PMTILES_PROTOCOL + url), allocator), allocator);
                 }
 
+                // Translate tile type field to source encoding.
+                if (header.tile_type == pmtiles::TILETYPE_MLT) {
+                    doc.AddMember("encoding", "mlt", allocator);
+                }
+
                 if (!doc.HasMember("bounds")) {
                     doc.AddMember("bounds", rapidjson::Value(), allocator);
                 }

render-test/render_test.cpp

@@ -131,6 +131,57 @@ ArgumentsTuple parseArguments(int argc, char** argv) {
                           updateResults,
                           std::move(testFilter)};
 }
+
+void runWithAlternateSources(TestRunner& runner, TestMetadata& metadata, bool& errored, bool& passed) {
+    constexpr auto replacementsKey = "source-replace";
+    constexpr auto targetKey = "replace";
+    constexpr auto sourceKey = "with";
+    constexpr auto sourcesKey = "sources";
+
+    if (!metadata.document.HasMember("metadata") || !metadata.document["metadata"].HasMember("test")) {
+        return;
+    }
+
+    auto& testElement = metadata.document["metadata"]["test"];
+    if (!testElement.HasMember(replacementsKey) || !testElement[replacementsKey].IsArray()) {
+        return;
+    }
+
+    const auto& replacesElement = testElement[replacementsKey];
+    if (!replacesElement.IsArray() || replacesElement.Empty()) {
+        return;
+    }
+
+    auto& sources = metadata.document[sourcesKey];
+
+    // Each item in the source replacements array...
+    for (auto i = replacesElement.Begin(); i != replacesElement.End(); ++i) {
+        const auto& entry = *i;
+        if (entry.IsObject() && entry.HasMember(targetKey) && entry.HasMember(sourceKey) &&
+            entry[targetKey].IsString() && entry[sourceKey].IsString()) {
+            const auto* targetName = entry[targetKey].GetString();
+            const auto* sourceName = entry[sourceKey].GetString();
+            if (sources.HasMember(targetName) && sources[targetName].IsObject() && sources.HasMember(sourceName) &&
+                sources[sourceName].IsObject()) {
+                // Swap the named sources
+                sources[targetName].Swap(sources[sourceName]);
+
+                // run the test again with the new source
+                runner.run(metadata);
+
+                // Restore the original source
+                sources[targetName].Swap(sources[sourceName]);
+
+                // stop if the test fails
+                errored = metadata.metricsErrored || metadata.renderErrored || metadata.labelCutOffFound;
+                passed = !errored && !metadata.metricsFailed && !metadata.renderFailed;
+                if (!passed) {
+                    break;
+                }
+            }
+        }
+    }
+}
 } // namespace
 namespace mbgl {
 
@@ -200,7 +251,7 @@ int runRenderTests(int argc, char** argv, std::function<void()> testStatus) {
         if (it != ignores.end()) {
             metadata.ignoredTest = shouldIgnore = true;
             ignoreReason = it->second;
-            if (ignoreReason.rfind("skip", 0) == 0) {
+            if (ignoreReason.starts_with("skip")) {
                 printf(ANSI_COLOR_GRAY "* skipped %s (%s)" ANSI_COLOR_RESET "\n", id.c_str(), ignoreReason.c_str());
                 mbgl::Log::Info(mbgl::Event::General, "* skipped " + id + "(" + ignoreReason + ")");
                 continue;
@@ -217,6 +268,10 @@ int runRenderTests(int argc, char** argv, std::function<void()> testStatus) {
         bool errored = metadata.metricsErrored || metadata.renderErrored || metadata.labelCutOffFound;
         bool passed = !errored && !metadata.metricsFailed && !metadata.renderFailed;
 
+        if (passed) {
+            runWithAlternateSources(runner, metadata, errored, passed);
+        }
+
         if (shouldIgnore) {
             if (passed) {
                 status = "ignored passed";

src/mbgl/geometry/dem_data.cpp

@@ -3,7 +3,7 @@
 
 namespace mbgl {
 
-DEMData::DEMData(const PremultipliedImage& _image, Tileset::DEMEncoding _encoding)
+DEMData::DEMData(const PremultipliedImage& _image, Tileset::RasterEncoding _encoding)
     : dim(_image.size.height),
       // extra two pixels per row for border backfilling on either edge
       stride(dim + 2),
@@ -99,7 +99,7 @@ const std::array<float, 4>& DEMData::getUnpackVector() const {
     // https://aws.amazon.com/public-datasets/terrain/
     static const std::array<float, 4> unpackTerrarium = {{256.0f, 1.0f, 1.0f / 256.0f, 32768.0f}};
 
-    return encoding == Tileset::DEMEncoding::Terrarium ? unpackTerrarium : unpackMapbox;
+    return encoding == Tileset::RasterEncoding::Terrarium ? unpackTerrarium : unpackMapbox;
 }
 
 } // namespace mbgl

src/mbgl/geometry/dem_data.hpp

@@ -13,7 +13,7 @@ namespace mbgl {
 
 class DEMData {
 public:
-    DEMData(const PremultipliedImage& image, Tileset::DEMEncoding encoding);
+    DEMData(const PremultipliedImage& image, Tileset::RasterEncoding encoding);
     void backfillBorder(const DEMData& borderTileData, int8_t dx, int8_t dy);
 
     int32_t get(int32_t x, int32_t y) const;
@@ -24,7 +24,7 @@ public:
 
     const int32_t dim;
     const int32_t stride;
-    const Tileset::DEMEncoding encoding;
+    const Tileset::RasterEncoding encoding;
 
 private:
     std::shared_ptr<PremultipliedImage> image;

src/mbgl/gfx/fill_generator.cpp

@@ -54,10 +54,10 @@ std::size_t totalVerticesCheck(const GeometryCollection& polygon) {
 
 void addFillIndices(SegmentVector& fillSegments,
                     gfx::IndexVector<gfx::Triangles>& fillIndexes,
-                    std::vector<uint32_t>& indices,
-                    std::size_t startVertices,
-                    std::size_t totalVertices) {
-    std::size_t nIndices = indices.size();
+                    const std::span<const uint32_t>& indices,
+                    const std::size_t startVertices,
+                    const std::size_t totalVertices) {
+    const std::size_t nIndices = indices.size();
     assert(nIndices % 3 == 0);
 
     if (fillSegments.empty() ||
@@ -66,10 +66,13 @@ void addFillIndices(SegmentVector& fillSegments,
     }
 
     auto& triangleSegment = fillSegments.back();
-    assert(triangleSegment.vertexLength <= std::numeric_limits<uint16_t>::max());
+    assert(triangleSegment.vertexLength + totalVertices <= std::numeric_limits<uint16_t>::max());
     const auto triangleIndex = static_cast<uint16_t>(triangleSegment.vertexLength);
 
     for (std::size_t i = 0; i < nIndices; i += 3) {
+        assert(
+            std::max({triangleIndex + indices[i + 0], triangleIndex + indices[i + 1], triangleIndex + indices[i + 2]}) <
+            triangleIndex + totalVertices);
         fillIndexes.emplace_back(
             triangleIndex + indices[i], triangleIndex + indices[i + 1], triangleIndex + indices[i + 2]);
     }
@@ -78,8 +81,8 @@ void addFillIndices(SegmentVector& fillSegments,
     triangleSegment.indexLength += nIndices;
 }
 
-void addOutlineIndices(std::size_t base,
-                       std::size_t nVertices,
+void addOutlineIndices(const std::size_t base,
+                       const std::size_t nVertices,
                        SegmentVector& lineSegments,
                        gfx::IndexVector<gfx::Lines>& lineIndexes) {
     if (nVertices == 0) return;
@@ -206,21 +209,36 @@ void generateFillAndOutineBuffers(const GeometryCollection& geometry,
     gfx::PolylineGeneratorOptions lineOptions;
     lineOptions.type = FeatureType::Polygon;
 
+    // If we have pre-tessellated geometry, multi-polygons are tessellated
+    // together, so we need to add them to the fill segment all at once.
+    if (!geometry.getTriangles().empty()) {
+        const std::size_t startVertices = fillVertices.elements();
+        std::size_t totalVertices = 0;
+        for (const auto& polygon : geometry) {
+            totalVertices += polygon.size();
+            addRingVertices(fillVertices, polygon);
+        }
+        addFillIndices(fillSegments, fillIndexes, geometry.getTriangles(), startVertices, totalVertices);
+        return;
+    }
+
     for (auto& polygon : classifyRings(geometry)) {
         // Optimize polygons with many interior rings for earcut tesselation.
         limitHoles(polygon, 500);
 
-        std::size_t totalVertices = totalVerticesCheck(polygon);
-        std::size_t startVertices = fillVertices.elements();
+        const std::size_t totalVertices = totalVerticesCheck(polygon);
+        const std::size_t startVertices = fillVertices.elements();
 
         for (const auto& ring : polygon) {
-            std::size_t base = fillVertices.elements();
-            std::size_t nVertices = addRingVertices(fillVertices, ring);
+            const std::size_t base = fillVertices.elements();
+            const std::size_t nVertices = addRingVertices(fillVertices, ring);
             addOutlineIndices(base, nVertices, basicLineSegments, basicLineIndexes);
             lineGenerator.generate(ring, lineOptions);
         }
 
+        // tessellate, if no triangles are provided
         std::vector<uint32_t> indices = mapbox::earcut(polygon);
+
         addFillIndices(fillSegments, fillIndexes, indices, startVertices, totalVertices);
     }
 }

src/mbgl/gfx/hillshade_prepare_drawable_data.hpp

@@ -11,13 +11,13 @@ namespace gfx {
 
 class HillshadePrepareDrawableData : public DrawableData {
 public:
-    HillshadePrepareDrawableData(int32_t stride_, Tileset::DEMEncoding encoding_, uint8_t maxzoom_)
+    HillshadePrepareDrawableData(int32_t stride_, Tileset::RasterEncoding encoding_, uint8_t maxzoom_)
         : stride(stride_),
           encoding(encoding_),
           maxzoom(maxzoom_) {}
 
     int32_t stride;
-    Tileset::DEMEncoding encoding;
+    Tileset::RasterEncoding encoding;
     uint8_t maxzoom;
 };
 

src/mbgl/programs/programs.cpp

@@ -0,0 +1,78 @@
+#include <mbgl/programs/programs.hpp>
+#include <mbgl/programs/background_program.hpp>
+#include <mbgl/programs/circle_program.hpp>
+#include <mbgl/programs/heatmap_program.hpp>
+#include <mbgl/programs/hillshade_program.hpp>
+#include <mbgl/programs/fill_extrusion_program.hpp>
+#include <mbgl/programs/fill_program.hpp>
+#include <mbgl/programs/line_program.hpp>
+#include <mbgl/programs/raster_program.hpp>
+#include <mbgl/programs/symbol_program.hpp>
+#include <mbgl/util/logging.hpp>
+
+namespace mbgl {
+
+Programs::Programs(const ProgramParameters& programParameters_)
+    : programParameters(programParameters_) {}
+
+Programs::~Programs() = default;
+
+namespace {
+/// @brief Register a list of types with a shader registry instance
+/// @tparam ...T Type list parameter pack
+/// @param registry A shader registry instance
+/// programParameters_ ProgramParameters used to initialize each instance
+template <typename... T>
+void registerTypes(gfx::ShaderRegistry& registry, const ProgramParameters& programParameters_) {
+    /// The following fold expression will create a shared_ptr for every type
+    /// in the parameter pack and register it with the shader registry.
+
+    /// Registration calls are wrapped in a lambda that throws on registration
+    /// failure, we shouldn't expect registration to faill unless the shader
+    /// registry instance provided already has conflicting programs present.
+    (
+        [](bool expr) {
+            if (!expr) {
+                throw std::runtime_error("Failed to register " + std::string(T::Name) + " with shader registry!");
+            }
+        }(registry.getLegacyGroup().registerShader(std::make_shared<T>(programParameters_))),
+        ...);
+}
+} // namespace
+
+void Programs::registerWith(gfx::ShaderRegistry& registry) {
+#if MLN_LEGACY_RENDERER
+    /// The following types will be registered
+    registerTypes<BackgroundProgram,
+                  BackgroundPatternProgram,
+                  RasterProgram,
+                  HeatmapProgram,
+                  HeatmapTextureProgram,
+                  HillshadeProgram,
+                  HillshadePrepareProgram,
+                  FillProgram,
+                  FillPatternProgram,
+                  FillOutlineProgram,
+                  FillOutlinePatternProgram,
+                  FillExtrusionProgram,
+                  FillExtrusionPatternProgram,
+                  CircleProgram,
+                  LineProgram,
+                  LineGradientProgram,
+                  LineSDFProgram,
+                  LinePatternProgram,
+                  SymbolIconProgram,
+                  SymbolSDFIconProgram,
+                  SymbolSDFTextProgram,
+                  SymbolTextAndIconProgram,
+                  CollisionBoxProgram,
+                  CollisionCircleProgram,
+                  DebugProgram,
+                  ClippingMaskProgram>(registry, programParameters);
+#else
+    /// The following types will be registered
+    registerTypes<DebugProgram, ClippingMaskProgram>(registry, programParameters);
+#endif
+}
+
+} // namespace mbgl

src/mbgl/renderer/buckets/hillshade_bucket.cpp

@@ -6,7 +6,7 @@ namespace mbgl {
 
 using namespace style;
 
-HillshadeBucket::HillshadeBucket(PremultipliedImage&& image_, Tileset::DEMEncoding encoding)
+HillshadeBucket::HillshadeBucket(PremultipliedImage&& image_, Tileset::RasterEncoding encoding)
     : demdata(image_, encoding) {}
 
 HillshadeBucket::HillshadeBucket(DEMData&& demdata_)

src/mbgl/renderer/buckets/hillshade_bucket.hpp

@@ -19,8 +19,8 @@ using HillshadeLayoutVertex = gfx::Vertex<TypeList<attributes::pos, attributes::
 
 class HillshadeBucket final : public Bucket {
 public:
-    HillshadeBucket(PremultipliedImage&&, Tileset::DEMEncoding encoding);
-    HillshadeBucket(std::shared_ptr<PremultipliedImage>, Tileset::DEMEncoding encoding);
+    HillshadeBucket(PremultipliedImage&&, Tileset::RasterEncoding encoding);
+    HillshadeBucket(std::shared_ptr<PremultipliedImage>, Tileset::RasterEncoding encoding);
     HillshadeBucket(DEMData&&);
     ~HillshadeBucket() override;
 

src/mbgl/renderer/buckets/line_bucket.cpp

@@ -79,7 +79,7 @@ void LineBucket::addGeometry(const GeometryCoordinates& coordinates,
     const std::size_t first = [&coordinates, &len] {
         std::size_t i = 0;
         // If the line has duplicate vertices at the start, adjust index to remove them.
-        while (i < len - 1 && coordinates[i] == coordinates[i + 1]) {
+        while (i + 1 < len && coordinates[i] == coordinates[i + 1]) {
             i++;
         }
         return i;
@@ -102,17 +102,16 @@ void LineBucket::addGeometry(const GeometryCoordinates& coordinates,
         return;
     }
 
-    const auto& props = feature.getProperties();
-    auto clip_start_it = props.find("mapbox_clip_start");
-    auto clip_end_it = props.find("mapbox_clip_end");
-    if (clip_start_it != props.end() && clip_end_it != props.end()) {
+    const auto clip_start = feature.getValue("mapbox_clip_start");
+    const auto clip_end = feature.getValue("mapbox_clip_end");
+    if (clip_start && clip_end) {
         double total_length = 0.0;
         for (std::size_t i = first; i < len - 1; ++i) {
             total_length += util::dist<double>(coordinates[i], coordinates[i + 1]);
         }
 
         options.clipDistances = gfx::PolylineGeneratorDistances{
-            *numericValue<double>(clip_start_it->second), *numericValue<double>(clip_end_it->second), total_length};
+            *numericValue<double>(*clip_start), *numericValue<double>(*clip_end), total_length};
     }
 
     options.joinType = layout.evaluate<LineJoin>(zoom, feature, canonical);

src/mbgl/renderer/layers/hillshade_prepare_layer_tweaker.cpp

@@ -22,8 +22,8 @@ constexpr std::array<float, 4> unpackMapbox = {{6553.6f, 25.6f, 0.1f, 10000.0f}}
 // https://aws.amazon.com/public-datasets/terrain/
 constexpr std::array<float, 4> unpackTerrarium = {{256.0f, 1.0f, 1.0f / 256.0f, 32768.0f}};
 
-constexpr const std::array<float, 4>& getUnpackVector(const Tileset::DEMEncoding encoding) {
-    return (encoding == Tileset::DEMEncoding::Terrarium) ? unpackTerrarium : unpackMapbox;
+constexpr const std::array<float, 4>& getUnpackVector(const Tileset::RasterEncoding encoding) {
+    return (encoding == Tileset::RasterEncoding::Terrarium) ? unpackTerrarium : unpackMapbox;
 }
 } // namespace
 

src/mbgl/renderer/render_source.cpp

@@ -24,6 +24,7 @@ std::unique_ptr<RenderSource> RenderSource::create(const Immutable<Source::Impl>
                                                    const TaggedScheduler& threadPool_) {
     switch (impl->type) {
         case SourceType::Vector:
+            // the TileSet isn't available yet, so we can't make different sources by format
             return std::make_unique<RenderVectorSource>(staticImmutableCast<TileSource::Impl>(impl),
                                                         std::move(threadPool_));
         case SourceType::Raster:

src/mbgl/renderer/sources/render_vector_source.cpp

@@ -1,8 +1,10 @@
 #include <mbgl/renderer/sources/render_vector_source.hpp>
+
 #include <mbgl/renderer/render_tile.hpp>
 #include <mbgl/renderer/paint_parameters.hpp>
-#include <mbgl/tile/vector_tile.hpp>
 #include <mbgl/renderer/tile_parameters.hpp>
+#include <mbgl/tile/vector_mlt_tile.hpp>
+#include <mbgl/tile/vector_mvt_tile.hpp>
 
 namespace mbgl {
 
@@ -20,17 +22,29 @@ void RenderVectorSource::updateInternal(const Tileset& tileset,
                                         const bool needsRendering,
                                         const bool needsRelayout,
                                         const TileParameters& parameters) {
-    tilePyramid.update(layers,
-                       needsRendering,
-                       needsRelayout,
-                       parameters,
-                       *baseImpl,
-                       util::tileSize_I,
-                       tileset.zoomRange,
-                       tileset.bounds,
-                       [&](const OverscaledTileID& tileID, TileObserver* observer_) {
-                           return std::make_unique<VectorTile>(tileID, baseImpl->id, parameters, tileset, observer_);
-                       });
+    tilePyramid.update(
+        layers,
+        needsRendering,
+        needsRelayout,
+        parameters,
+        *baseImpl,
+        util::tileSize_I,
+        tileset.zoomRange,
+        tileset.bounds,
+        [&](const OverscaledTileID& tileID, TileObserver* observer_) -> std::unique_ptr<VectorTile> {
+            if (!isMLT.has_value()) {
+                auto impl = staticImmutableCast<style::TileSource::Impl>(baseImpl);
+                assert(impl->tileset); // we should have one by now
+                if (impl->tileset) {
+                    isMLT = (impl->tileset->vectorEncoding == Tileset::VectorEncoding::MLT);
+                }
+            }
+            if (isMLT && *isMLT) {
+                return std::make_unique<VectorMLTTile>(tileID, baseImpl->id, parameters, tileset, observer_);
+            } else {
+                return std::make_unique<VectorMVTTile>(tileID, baseImpl->id, parameters, tileset, observer_);
+            }
+        });
 }
 
 } // namespace mbgl

src/mbgl/renderer/sources/render_vector_source.hpp

@@ -17,6 +17,9 @@ private:
                         bool needsRelayout,
                         const TileParameters&) override;
     const std::optional<Tileset>& getTileset() const override;
+
+private:
+    std::optional<bool> isMLT;
 };
 
 } // namespace mbgl

src/mbgl/style/conversion/raster_dem_options.cpp

@@ -1,34 +0,0 @@
-#include <mbgl/style/conversion/raster_dem_options.hpp>
-#include <mbgl/style/conversion_impl.hpp>
-#include <mbgl/style/expression/dsl.hpp>
-
-#include <sstream>
-
-namespace mbgl {
-namespace style {
-namespace conversion {
-
-std::optional<RasterDEMOptions> Converter<RasterDEMOptions>::operator()(const Convertible& value, Error& error) const {
-    RasterDEMOptions options;
-
-    auto encodingValue = objectMember(value, "encoding");
-    if (encodingValue) {
-        std::optional<std::string> encoding = toString(*encodingValue);
-        if (encoding && *encoding == "terrarium") {
-            options.encoding = {Tileset::DEMEncoding::Terrarium};
-        } else if (encoding && *encoding == "mapbox") {
-            options.encoding = {Tileset::DEMEncoding::Mapbox};
-        } else {
-            error.message =
-                "invalid raster-dem encoding type - valid types are 'mapbox' "
-                "and 'terrarium'";
-            return std::nullopt;
-        }
-    }
-
-    return {std::move(options)};
-}
-
-} // namespace conversion
-} // namespace style
-} // namespace mbgl

src/mbgl/style/conversion/source.cpp

@@ -2,7 +2,7 @@
 #include <mbgl/style/conversion/coordinate.hpp>
 #include <mbgl/style/conversion/geojson.hpp>
 #include <mbgl/style/conversion/geojson_options.hpp>
-#include <mbgl/style/conversion/raster_dem_options.hpp>
+#include <mbgl/style/conversion/source_options.hpp>
 #include <mbgl/style/conversion/tileset.hpp>
 #include <mbgl/style/conversion_impl.hpp>
 #include <mbgl/style/sources/geojson_source.hpp>
@@ -16,8 +16,8 @@ namespace mbgl {
 namespace style {
 namespace conversion {
 
-// A tile source can either specify a URL to TileJSON, or inline TileJSON.
 namespace {
+// A tile source can either specify a URL to TileJSON, or inline TileJSON.
 std::optional<variant<std::string, Tileset>> convertURLOrTileset(const Convertible& value, Error& error) {
     auto urlVal = objectMember(value, "url");
     if (!urlVal) {
@@ -25,7 +25,7 @@ std::optional<variant<std::string, Tileset>> convertURLOrTileset(const Convertib
         if (!tileset) {
             return std::nullopt;
         }
-        return {*tileset};
+        return {std::move(*tileset)};
     }
 
     std::optional<std::string> url = toString(*urlVal);
@@ -34,7 +34,7 @@ std::optional<variant<std::string, Tileset>> convertURLOrTileset(const Convertib
         return std::nullopt;
     }
 
-    return {*url};
+    return {std::move(*url)};
 }
 
 std::optional<std::unique_ptr<Source>> convertRasterSource(const std::string& id,
@@ -83,7 +83,7 @@ std::optional<std::unique_ptr<Source>> convertRasterDEMSource(const std::string&
            parameters. Since style.json can contain TileJSON parameter overrides or non-TileJSON spec parameters, a
            separate mechanism is needed. Ideally these two pathways share parsing logic.
     */
-    std::optional<RasterDEMOptions> options = convert<RasterDEMOptions>(value, error);
+    auto options = convert<SourceOptions>(value, error);
 
     return {std::make_unique<RasterDEMSource>(id, std::move(*urlOrTileset), tileSize, options)};
 }
@@ -91,11 +91,11 @@ std::optional<std::unique_ptr<Source>> convertRasterDEMSource(const std::string&
 std::optional<std::unique_ptr<Source>> convertVectorSource(const std::string& id,
                                                            const Convertible& value,
                                                            Error& error) {
-    std::optional<variant<std::string, Tileset>> urlOrTileset = convertURLOrTileset(value, error);
+    auto urlOrTileset = convertURLOrTileset(value, error);
     if (!urlOrTileset) {
         return std::nullopt;
     }
-    auto maxzoomValue = objectMember(value, "maxzoom");
+    const auto maxzoomValue = objectMember(value, "maxzoom");
     std::optional<float> maxzoom;
     if (maxzoomValue) {
         maxzoom = toNumber(*maxzoomValue);
@@ -104,7 +104,7 @@ std::optional<std::unique_ptr<Source>> convertVectorSource(const std::string& id
             return std::nullopt;
         }
     }
-    auto minzoomValue = objectMember(value, "minzoom");
+    const auto minzoomValue = objectMember(value, "minzoom");
     std::optional<float> minzoom;
     if (minzoomValue) {
         minzoom = toNumber(*minzoomValue);
@@ -113,7 +113,20 @@ std::optional<std::unique_ptr<Source>> convertVectorSource(const std::string& id
             return std::nullopt;
         }
     }
-    return {std::make_unique<VectorSource>(id, std::move(*urlOrTileset), std::move(maxzoom), std::move(minzoom))};
+    const auto encodingValue = objectMember(value, "encoding");
+    auto encoding = Tileset::VectorEncoding::Mapbox;
+    if (encodingValue) {
+        const auto encodingStr = toString(*encodingValue);
+        if (encodingStr && encodingStr == "mvt") {
+            encoding = Tileset::VectorEncoding::Mapbox;
+        } else if (encodingStr && encodingStr == "mlt") {
+            encoding = Tileset::VectorEncoding::MLT;
+        } else {
+            error.message = "invalid encoding";
+            return std::nullopt;
+        }
+    }
+    return {std::make_unique<VectorSource>(id, std::move(*urlOrTileset), maxzoom, minzoom, encoding)};
 }
 
 std::optional<std::unique_ptr<Source>> convertGeoJSONSource(const std::string& id,

src/mbgl/style/conversion/source_options.cpp

@@ -0,0 +1,33 @@
+#include <mbgl/style/conversion/source_options.hpp>
+#include <mbgl/style/conversion_impl.hpp>
+#include <mbgl/style/expression/dsl.hpp>
+
+namespace mbgl {
+namespace style {
+namespace conversion {
+
+std::optional<SourceOptions> Converter<SourceOptions>::operator()(const Convertible& value, Error& error) const {
+    const auto encodingValue = objectMember(value, "encoding");
+    if (encodingValue) {
+        const auto encoding = toString(*encodingValue);
+        if (encoding && *encoding == "terrarium") {
+            return {{.rasterEncoding = Tileset::RasterEncoding::Terrarium}};
+        } else if (encoding && *encoding == "mapbox") {
+            return {{.rasterEncoding = Tileset::RasterEncoding::Mapbox}};
+        } else if (encoding && *encoding == "mvt") {
+            return {{.vectorEncoding = Tileset::VectorEncoding::Mapbox}};
+        } else if (encoding && *encoding == "mlt") {
+            return {{.vectorEncoding = Tileset::VectorEncoding::MLT}};
+        } else {
+            error.message =
+                "invalid encoding - valid types are 'mapbox' and 'terrarium' for raster sources, 'mvt' and 'mlt' for "
+                "vector sources";
+            return std::nullopt;
+        }
+    }
+    return {};
+}
+
+} // namespace conversion
+} // namespace style
+} // namespace mbgl

src/mbgl/style/conversion/tileset.cpp

@@ -1,5 +1,5 @@
 #include <mbgl/style/conversion/tileset.hpp>
-#include <mbgl/style/conversion/raster_dem_options.hpp>
+#include <mbgl/style/conversion/source_options.hpp>
 #include <mbgl/style/conversion_impl.hpp>
 #include <mbgl/util/geo.hpp>
 #include <mbgl/math/clamp.hpp>
@@ -39,10 +39,13 @@ std::optional<Tileset> Converter<Tileset>::operator()(const Convertible& value,
         }
     }
 
-    auto rasterDEMOptions = convert<RasterDEMOptions>(value, error);
-    if (rasterDEMOptions) {
-        if (std::optional<Tileset::DEMEncoding> encoding = rasterDEMOptions.value().encoding) {
-            result.encoding = encoding.value();
+    auto options = convert<SourceOptions>(value, error);
+    if (options) {
+        if (const auto encoding = options->rasterEncoding) {
+            result.rasterEncoding = encoding;
+        }
+        if (const auto encoding = options->vectorEncoding) {
+            result.vectorEncoding = encoding;
         }
     }
 

src/mbgl/style/sources/raster_dem_source.cpp

@@ -15,7 +15,7 @@ namespace style {
 RasterDEMSource::RasterDEMSource(std::string id,
                                  variant<std::string, Tileset> urlOrTileset_,
                                  uint16_t tileSize,
-                                 std::optional<RasterDEMOptions> options_)
+                                 std::optional<SourceOptions> options_)
     : RasterSource(std::move(id), std::move(urlOrTileset_), tileSize, SourceType::RasterDEM),
       options(std::move(options_)) {}
 
@@ -30,8 +30,8 @@ bool RasterDEMSource::supportsLayerType(const mbgl::style::LayerTypeInfo* info)
 
 void RasterDEMSource::setTilesetOverrides(Tileset& tileset) {
     if (options) {
-        if (std::optional<Tileset::DEMEncoding> encoding = options.value().encoding) {
-            tileset.encoding = encoding.value();
+        if (const auto encoding = options->rasterEncoding) {
+            tileset.rasterEncoding = encoding;
         }
     }
 }

src/mbgl/style/sources/vector_source.cpp

@@ -10,6 +10,7 @@
 #include <mbgl/util/constants.hpp>
 #include <mbgl/util/exception.hpp>
 #include <mbgl/util/mapbox.hpp>
+#include <string>
 
 namespace mbgl {
 namespace style {
@@ -17,10 +18,12 @@ namespace style {
 VectorSource::VectorSource(std::string id,
                            variant<std::string, Tileset> urlOrTileset_,
                            std::optional<float> maxZoom_,
-                           std::optional<float> minZoom_)
+                           std::optional<float> minZoom_,
+                           Tileset::VectorEncoding encoding_)
     : TileSource(id, urlOrTileset_, util::tileSize_I, SourceType::Vector),
       maxZoom(std::move(maxZoom_)),
-      minZoom(std::move(minZoom_)) {}
+      minZoom(std::move(minZoom_)),
+      encoding(encoding_) {}
 
 void VectorSource::setTilesetOverrides(Tileset& tileset) {
     if (maxZoom) {

src/mbgl/tile/geometry_tile_data.hpp

@@ -4,11 +4,14 @@
 #include <mbgl/util/feature.hpp>
 
 #include <cstdint>
+#include <memory>
+#include <span>
 #include <string>
 #include <vector>
-#include <memory>
-#include <optional>
 
+namespace mlt {
+class MapLibreTile;
+}
 namespace mbgl {
 
 class CanonicalTileID;
@@ -44,8 +47,17 @@ public:
 
     GeometryCollection clone() const { return GeometryCollection(*this); }
 
+    const auto& getTriangles() const { return triangles; }
+    void setTriangles(std::shared_ptr<const mlt::MapLibreTile> owner, std::span<const std::uint32_t> triangles_) {
+        triangleOwner = std::move(owner);
+        triangles = triangles_;
+    }
+
 private:
     GeometryCollection(const GeometryCollection&) = default;
+
+    std::shared_ptr<const mlt::MapLibreTile> triangleOwner;
+    std::span<const std::uint32_t> triangles = {};
 };
 
 class GeometryTileFeature {

src/mbgl/tile/raster_dem_tile.cpp

@@ -24,7 +24,7 @@ RasterDEMTile::RasterDEMTile(const OverscaledTileID& id_,
       threadPool(parameters.threadPool),
       mailbox(std::make_shared<Mailbox>(*Scheduler::GetCurrent())),
       worker(parameters.threadPool, ActorRef<RasterDEMTile>(*this, mailbox)) {
-    encoding = tileset.encoding;
+    encoding = tileset.rasterEncoding.value_or(Tileset::RasterEncoding::Mapbox);
     if (id.canonical.y == 0) {
         // this tile doesn't have upper neighboring tiles so marked those as backfilled
         neighboringTiles = neighboringTiles | DEMTileNeighbors::NoUpper;

src/mbgl/tile/raster_dem_tile.hpp

@@ -99,7 +99,7 @@ private:
     Actor<RasterDEMTileWorker> worker;
 
     uint64_t correlationID = 0;
-    Tileset::DEMEncoding encoding;
+    Tileset::RasterEncoding encoding;
 
     // Contains the Bucket object for the tile. Buckets are render
     // objects and they get added by tile parsing operations.

src/mbgl/tile/raster_dem_tile_worker.cpp

@@ -11,7 +11,7 @@ RasterDEMTileWorker::RasterDEMTileWorker(const ActorRef<RasterDEMTileWorker>&, A
 
 void RasterDEMTileWorker::parse(const std::shared_ptr<const std::string>& data,
                                 uint64_t correlationID,
-                                Tileset::DEMEncoding encoding) {
+                                Tileset::RasterEncoding encoding) {
     if (!data) {
         parent.invoke(&RasterDEMTile::onParsed, nullptr,
                       correlationID); // No data; empty tile.

src/mbgl/tile/raster_dem_tile_worker.hpp

@@ -14,7 +14,9 @@ class RasterDEMTileWorker {
 public:
     RasterDEMTileWorker(const ActorRef<RasterDEMTileWorker>&, ActorRef<RasterDEMTile>);
 
-    void parse(const std::shared_ptr<const std::string>& data, uint64_t correlationID, Tileset::DEMEncoding encoding);
+    void parse(const std::shared_ptr<const std::string>& data,
+               uint64_t correlationID,
+               Tileset::RasterEncoding encoding);
 
 private:
     ActorRef<RasterDEMTile> parent;

src/mbgl/tile/vector_mlt_tile.cpp

@@ -0,0 +1,24 @@
+#include <mbgl/tile/vector_mlt_tile.hpp>
+
+#include <mbgl/renderer/tile_parameters.hpp>
+#include <mbgl/tile/tile_loader_impl.hpp>
+#include <mbgl/tile/vector_mlt_tile_data.hpp>
+
+#include <utility>
+
+namespace mbgl {
+
+VectorMLTTile::VectorMLTTile(const OverscaledTileID& id_,
+                             std::string sourceID_,
+                             const TileParameters& parameters_,
+                             const Tileset& tileset_,
+                             TileObserver* observer_)
+    : VectorTile(id_, std::move(sourceID_), parameters_, tileset_, observer_) {}
+
+void VectorMLTTile::setData(const std::shared_ptr<const std::string>& data_) {
+    if (!obsolete) {
+        GeometryTile::setData(data_ ? std::make_unique<VectorMLTTileData>(data_) : nullptr);
+    }
+}
+
+} // namespace mbgl

src/mbgl/tile/vector_mlt_tile.hpp

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <mbgl/tile/geometry_tile.hpp>
+#include <mbgl/tile/tile_loader.hpp>
+#include <mbgl/tile/vector_tile.hpp>
+
+namespace mbgl {
+
+class Tileset;
+class TileParameters;
+
+class VectorMLTTile : public VectorTile {
+public:
+    VectorMLTTile(const OverscaledTileID&,
+                  std::string sourceID,
+                  const TileParameters&,
+                  const Tileset&,
+                  TileObserver* observer = nullptr);
+
+    void setData(const std::shared_ptr<const std::string>& data) override;
+};
+
+} // namespace mbgl

src/mbgl/tile/vector_mlt_tile_data.cpp

@@ -0,0 +1,220 @@
+#include <mapbox/feature.hpp>
+#include <mbgl/tile/vector_mlt_tile_data.hpp>
+
+#include <mbgl/util/constants.hpp>
+#include <mbgl/util/instrumentation.hpp>
+#include <mbgl/util/logging.hpp>
+
+#include <mlt/decoder.hpp>
+#include <mlt/layer.hpp>
+
+namespace mbgl {
+
+using GeometryType = mlt::metadata::tileset::GeometryType;
+
+VectorMLTTileFeature::VectorMLTTileFeature(std::shared_ptr<const MapLibreTile> tile_,
+                                           const mlt::Layer& layer_,
+                                           const mlt::Feature& feature_,
+                                           std::uint32_t extent_)
+    : tile(std::move(tile_)),
+      layer(layer_),
+      feature(feature_),
+      extent(extent_) {}
+
+FeatureType VectorMLTTileFeature::getType() const {
+    switch (feature.getGeometry().type) {
+        case GeometryType::POINT:
+            return FeatureType::Point;
+        case GeometryType::MULTIPOINT:
+        case GeometryType::MULTILINESTRING:
+        case GeometryType::LINESTRING:
+            return FeatureType::LineString;
+        case GeometryType::POLYGON:
+        case GeometryType::MULTIPOLYGON:
+            return FeatureType::Polygon;
+        default:
+            return FeatureType::Unknown;
+    }
+}
+
+namespace {
+struct PropertyVisitor {
+    Value operator()(std::nullptr_t) const { return mapbox::feature::null_value; }
+    Value operator()(bool value) const { return value; }
+    Value operator()(std::uint32_t value) const { return value; }
+    Value operator()(std::uint64_t value) const { return value; }
+    Value operator()(float value) const { return value; }
+    Value operator()(double value) const { return value; }
+    Value operator()(std::string_view value) const { return std::string(value); }
+
+    template <typename T>
+    Value operator()(std::optional<T> value) const {
+        return value ? operator()(*value) : NullValue();
+    }
+};
+} // namespace
+
+std::optional<Value> VectorMLTTileFeature::getValue(const std::string& key) const {
+    if (auto prop = feature.getProperty(key, layer)) {
+        return std::visit(PropertyVisitor(), *prop);
+    }
+    return std::nullopt;
+}
+
+const PropertyMap& VectorMLTTileFeature::getProperties() const {
+    if (!properties) {
+        const PropertyVisitor visitor;
+        properties.emplace();
+        properties->reserve(layer.getProperties().size());
+        for (const auto& [key, props] : layer.getProperties()) {
+            auto value = props.getProperty(feature.getIndex());
+            auto prop = value ? std::visit(visitor, std::move(*value)) : mapbox::feature::null_value;
+            properties->emplace(key, std::move(prop));
+        }
+    }
+    return *properties;
+}
+
+FeatureIdentifier VectorMLTTileFeature::getID() const {
+    return feature.getID();
+}
+
+namespace {
+struct PointConverter {
+    double scale;
+    inline constexpr static GeometryCoordinate convert(double scale, const mlt::Coordinate& coord) {
+        return {static_cast<std::int16_t>(std::round(coord.x * scale)),
+                static_cast<std::int16_t>(std::round(coord.y * scale))};
+    }
+    GeometryCoordinate operator()(const mlt::Coordinate& coord) const { return convert(scale, coord); }
+    GeometryCoordinates operator()(const mlt::CoordVec& coords) const {
+        GeometryCoordinates result(coords.size());
+        std::ranges::transform(coords, result.begin(), *this);
+        return result;
+    }
+};
+} // namespace
+
+const GeometryCollection& VectorMLTTileFeature::getGeometries() const {
+    MLN_TRACE_FUNC();
+
+    if (!lines) {
+        const auto scale = static_cast<double>(util::EXTENT) / extent;
+        const auto& geometry = feature.getGeometry();
+        const PointConverter convert{scale};
+        switch (geometry.type) {
+            case GeometryType::POINT: {
+                const auto& geom = static_cast<const mlt::geometry::Point&>(geometry);
+                lines = GeometryCollection{{convert(geom.getCoordinate())}};
+                break;
+            }
+            case GeometryType::MULTIPOINT:
+            case GeometryType::LINESTRING: {
+                const auto& geom = static_cast<const mlt::geometry::MultiPoint&>(geometry);
+                lines = GeometryCollection{convert(geom.getCoordinates())};
+                break;
+            }
+            case GeometryType::POLYGON: {
+                const auto& geom = static_cast<const mlt::geometry::Polygon&>(geometry);
+                lines.emplace(geom.getRings().size());
+                std::ranges::transform(geom.getRings(), lines->begin(), convert);
+                if (!geometry.getTriangles().empty()) {
+                    lines->setTriangles(tile, geometry.getTriangles());
+                }
+                break;
+            }
+            case GeometryType::MULTILINESTRING: {
+                const auto& geom = static_cast<const mlt::geometry::MultiLineString&>(geometry);
+                lines.emplace(geom.getLineStrings().size());
+                std::ranges::transform(geom.getLineStrings(), lines->begin(), convert);
+                break;
+            }
+            case GeometryType::MULTIPOLYGON: {
+                const auto& geom = static_cast<const mlt::geometry::MultiPolygon&>(geometry);
+                const auto& polygons = geom.getPolygons();
+                using RingVec = mlt::geometry::MultiPolygon::RingVec;
+                lines.emplace(std::accumulate(
+                    polygons.begin(), polygons.end(), static_cast<std::size_t>(0), [](std::size_t a, const RingVec& b) {
+                        return a + b.size();
+                    }));
+                for (const auto& poly : polygons) {
+                    std::ranges::transform(poly, std::back_inserter(*lines), convert);
+                }
+                if (!geometry.getTriangles().empty()) {
+                    lines->setTriangles(tile, geometry.getTriangles());
+                }
+                break;
+            }
+            default:
+                lines.emplace();
+                break;
+        }
+    }
+    return *lines;
+}
+
+VectorMLTTileLayer::VectorMLTTileLayer(std::shared_ptr<const MapLibreTile> tile_, const mlt::Layer& layer_)
+    : tile(std::move(tile_)),
+      layer(layer_) {}
+
+std::size_t VectorMLTTileLayer::featureCount() const {
+    return layer.getFeatures().size();
+}
+
+std::unique_ptr<GeometryTileFeature> VectorMLTTileLayer::getFeature(std::size_t index) const {
+    const auto& features = layer.getFeatures();
+    const mlt::Feature* targetFeature = nullptr;
+    targetFeature = &features[index];
+    return std::make_unique<VectorMLTTileFeature>(tile, layer, *targetFeature, layer.getExtent());
+}
+
+std::string VectorMLTTileLayer::getName() const {
+    return layer.getName();
+}
+
+VectorMLTTileData::VectorMLTTileData(std::shared_ptr<const std::string> data_)
+    : data(std::move(data_)) {}
+
+VectorMLTTileData::VectorMLTTileData(const VectorMLTTileData& other)
+    : data(other.data),
+      tile(other.tile) {}
+
+std::unique_ptr<GeometryTileData> VectorMLTTileData::clone() const {
+    return std::make_unique<VectorMLTTileData>(*this);
+}
+
+std::unique_ptr<GeometryTileLayer> VectorMLTTileData::getLayer(const std::string& name) const {
+    MLN_TRACE_FUNC();
+
+    if (data && !tile) {
+        try {
+            mlt::DataView tileData{data->data(), data->size()};
+            tile = std::make_shared<MapLibreTile>(mlt::Decoder().decode(tileData));
+        } catch (const std::exception& ex) {
+            Log::Warning(Event::ParseTile, "MLT parse failed: " + std::string(ex.what()));
+        }
+        // We don't need the raw data anymore
+        data.reset();
+    }
+
+    if (tile) {
+        if (const auto* layer = tile->getLayer(name)) {
+            return std::make_unique<VectorMLTTileLayer>(tile, *layer);
+        }
+    }
+    return nullptr;
+}
+
+std::vector<std::string> VectorMLTTileData::layerNames() const {
+    if (data && !data->empty() && !tile) {
+        getLayer({});
+    }
+    if (tile) {
+        std::vector<std::string> result(tile->getLayers().size());
+        std::ranges::transform(tile->getLayers(), result.begin(), [](const auto& layer) { return layer.getName(); });
+        return result;
+    }
+    return {};
+}
+
+} // namespace mbgl

src/mbgl/tile/vector_mlt_tile_data.hpp

@@ -0,0 +1,85 @@
+#pragma once
+
+#include <mbgl/tile/geometry_tile_data.hpp>
+#include <mbgl/util/containers.hpp>
+
+#include <unordered_map>
+#include <functional>
+#include <utility>
+
+namespace mlt {
+class MapLibreTile;
+class Feature;
+class Layer;
+} // namespace mlt
+
+namespace mbgl {
+using MapLibreTile = mlt::MapLibreTile;
+
+class VectorMLTTileFeature : public GeometryTileFeature {
+public:
+    VectorMLTTileFeature(std::shared_ptr<const MapLibreTile>,
+                         const mlt::Layer& layer_,
+                         const mlt::Feature&,
+                         std::uint32_t extent);
+    VectorMLTTileFeature(const VectorMLTTileFeature&) = delete;
+    VectorMLTTileFeature(VectorMLTTileFeature&& other)
+        : tile(std::move(other.tile)),
+          layer(other.layer),
+          feature(other.feature),
+          extent(other.extent),
+          version(other.version),
+          lines(std::move(other.lines)),
+          properties(std::move(other.properties)) {}
+
+    VectorMLTTileFeature& operator=(VectorMLTTileFeature&&) = delete;
+    VectorMLTTileFeature& operator=(const VectorMLTTileFeature&) = delete;
+
+    FeatureType getType() const override;
+    std::optional<Value> getValue(const std::string& key) const override;
+    const PropertyMap& getProperties() const override;
+    FeatureIdentifier getID() const override;
+    const GeometryCollection& getGeometries() const override;
+
+private:
+    std::shared_ptr<const MapLibreTile> tile;
+    const mlt::Layer& layer;
+    mlt::Feature const& feature;
+    std::uint32_t extent;
+    int version;
+
+    // lazy init
+    mutable std::optional<GeometryCollection> lines;
+    mutable std::optional<PropertyMap> properties;
+};
+
+class VectorMLTTileLayer : public GeometryTileLayer {
+public:
+    VectorMLTTileLayer(std::shared_ptr<const MapLibreTile>, const mlt::Layer&);
+
+    std::size_t featureCount() const override;
+    std::unique_ptr<GeometryTileFeature> getFeature(std::size_t i) const override;
+    std::string getName() const override;
+
+private:
+    const std::shared_ptr<const MapLibreTile> tile;
+    const mlt::Layer& layer;
+};
+
+class VectorMLTTileData : public GeometryTileData {
+public:
+    VectorMLTTileData(std::shared_ptr<const std::string> data);
+    VectorMLTTileData(const VectorMLTTileData&);
+    VectorMLTTileData(VectorMLTTileData&&) = default;
+
+    std::unique_ptr<GeometryTileData> clone() const override;
+    std::unique_ptr<GeometryTileLayer> getLayer(const std::string& name) const override;
+
+    std::vector<std::string> layerNames() const;
+
+private:
+    mutable std::shared_ptr<const std::string> data;
+    mutable std::shared_ptr<const MapLibreTile> tile;
+};
+
+} // namespace mbgl

src/mbgl/tile/vector_mvt_tile.cpp

@@ -0,0 +1,24 @@
+#include <mbgl/tile/vector_mvt_tile.hpp>
+
+#include <mbgl/renderer/tile_parameters.hpp>
+#include <mbgl/tile/tile_loader_impl.hpp>
+#include <mbgl/tile/vector_mvt_tile_data.hpp>
+
+#include <utility>
+
+namespace mbgl {
+
+VectorMVTTile::VectorMVTTile(const OverscaledTileID& id_,
+                             std::string sourceID_,
+                             const TileParameters& parameters_,
+                             const Tileset& tileset_,
+                             TileObserver* observer_)
+    : VectorTile(id_, std::move(sourceID_), parameters_, tileset_, observer_) {}
+
+void VectorMVTTile::setData(const std::shared_ptr<const std::string>& data_) {
+    if (!obsolete) {
+        GeometryTile::setData(data_ ? std::make_unique<VectorMVTTileData>(data_) : nullptr);
+    }
+}
+
+} // namespace mbgl

src/mbgl/tile/vector_mvt_tile.hpp

@@ -0,0 +1,23 @@
+#pragma once
+
+#include <mbgl/tile/geometry_tile.hpp>
+#include <mbgl/tile/tile_loader.hpp>
+#include <mbgl/tile/vector_tile.hpp>
+
+namespace mbgl {
+
+class Tileset;
+class TileParameters;
+
+class VectorMVTTile : public VectorTile {
+public:
+    VectorMVTTile(const OverscaledTileID&,
+                  std::string sourceID,
+                  const TileParameters&,
+                  const Tileset&,
+                  TileObserver* observer = nullptr);
+
+    void setData(const std::shared_ptr<const std::string>& data) override;
+};
+
+} // namespace mbgl

src/mbgl/tile/vector_mvt_tile_data.cpp

@@ -1,14 +1,19 @@
-#include <mbgl/tile/vector_tile_data.hpp>
+#include <mbgl/tile/vector_mvt_tile_data.hpp>
+
 #include <mbgl/util/constants.hpp>
 #include <mbgl/util/instrumentation.hpp>
 #include <mbgl/util/logging.hpp>
 
+#if ANDROID
+#include <mlt/decoder.hpp>
+#endif
+
 namespace mbgl {
 
-VectorTileFeature::VectorTileFeature(const mapbox::vector_tile::layer& layer, const protozero::data_view& view)
+VectorMVTTileFeature::VectorMVTTileFeature(const mapbox::vector_tile::layer& layer, const protozero::data_view& view)
     : feature(view, layer) {}
 
-FeatureType VectorTileFeature::getType() const {
+FeatureType VectorMVTTileFeature::getType() const {
     switch (feature.getType()) {
         case mapbox::vector_tile::GeomType::POINT:
             return FeatureType::Point;
@@ -21,23 +26,23 @@ FeatureType VectorTileFeature::getType() const {
     }
 }
 
-std::optional<Value> VectorTileFeature::getValue(const std::string& key) const {
-    const std::optional<Value> value(feature.getValue(key));
-    return value->is<NullValue>() ? std::nullopt : value;
+std::optional<Value> VectorMVTTileFeature::getValue(const std::string& key) const {
+    const auto value = feature.getValue(key);
+    return value.is<NullValue>() ? std::nullopt : std::optional<Value>{std::move(value)};
 }
 
-const PropertyMap& VectorTileFeature::getProperties() const {
+const PropertyMap& VectorMVTTileFeature::getProperties() const {
     if (!properties) {
         properties = feature.getProperties();
     }
     return *properties;
 }
 
-FeatureIdentifier VectorTileFeature::getID() const {
+FeatureIdentifier VectorMVTTileFeature::getID() const {
     return feature.getID();
 }
 
-const GeometryCollection& VectorTileFeature::getGeometries() const {
+const GeometryCollection& VectorMVTTileFeature::getGeometries() const {
     MLN_TRACE_FUNC();
 
     if (!lines) {
@@ -57,30 +62,30 @@ const GeometryCollection& VectorTileFeature::getGeometries() const {
     return *lines;
 }
 
-VectorTileLayer::VectorTileLayer(std::shared_ptr<const std::string> data_, const protozero::data_view& view)
+VectorMVTTileLayer::VectorMVTTileLayer(std::shared_ptr<const std::string> data_, const protozero::data_view& view)
     : data(std::move(data_)),
       layer(view) {}
 
-std::size_t VectorTileLayer::featureCount() const {
+std::size_t VectorMVTTileLayer::featureCount() const {
     return layer.featureCount();
 }
 
-std::unique_ptr<GeometryTileFeature> VectorTileLayer::getFeature(std::size_t i) const {
-    return std::make_unique<VectorTileFeature>(layer, layer.getFeature(i));
+std::unique_ptr<GeometryTileFeature> VectorMVTTileLayer::getFeature(std::size_t i) const {
+    return std::make_unique<VectorMVTTileFeature>(layer, layer.getFeature(i));
 }
 
-std::string VectorTileLayer::getName() const {
+std::string VectorMVTTileLayer::getName() const {
     return layer.getName();
 }
 
-VectorTileData::VectorTileData(std::shared_ptr<const std::string> data_)
+VectorMVTTileData::VectorMVTTileData(std::shared_ptr<const std::string> data_)
     : data(std::move(data_)) {}
 
-std::unique_ptr<GeometryTileData> VectorTileData::clone() const {
-    return std::make_unique<VectorTileData>(data);
+std::unique_ptr<GeometryTileData> VectorMVTTileData::clone() const {
+    return std::make_unique<VectorMVTTileData>(data);
 }
 
-std::unique_ptr<GeometryTileLayer> VectorTileData::getLayer(const std::string& name) const {
+std::unique_ptr<GeometryTileLayer> VectorMVTTileData::getLayer(const std::string& name) const {
     MLN_TRACE_FUNC();
 
     if (!parsed) {
@@ -93,12 +98,12 @@ std::unique_ptr<GeometryTileLayer> VectorTileData::getLayer(const std::string& n
 
     auto it = layers.find(name);
     if (it != layers.end()) {
-        return std::make_unique<VectorTileLayer>(data, it->second);
+        return std::make_unique<VectorMVTTileLayer>(data, it->second);
     }
     return nullptr;
 }
 
-std::vector<std::string> VectorTileData::layerNames() const {
+std::vector<std::string> VectorMVTTileData::layerNames() const {
     return mapbox::vector_tile::buffer(*data).layerNames();
 }
 

src/mbgl/tile/vector_mvt_tile_data.hpp

@@ -20,9 +20,9 @@
 
 namespace mbgl {
 
-class VectorTileFeature : public GeometryTileFeature {
+class VectorMVTTileFeature : public GeometryTileFeature {
 public:
-    VectorTileFeature(const mapbox::vector_tile::layer&, const protozero::data_view&);
+    VectorMVTTileFeature(const mapbox::vector_tile::layer&, const protozero::data_view&);
 
     FeatureType getType() const override;
     std::optional<Value> getValue(const std::string& key) const override;
@@ -36,9 +36,9 @@ private:
     mutable std::optional<PropertyMap> properties;
 };
 
-class VectorTileLayer : public GeometryTileLayer {
+class VectorMVTTileLayer : public GeometryTileLayer {
 public:
-    VectorTileLayer(std::shared_ptr<const std::string> data, const protozero::data_view&);
+    VectorMVTTileLayer(std::shared_ptr<const std::string> data, const protozero::data_view&);
 
     std::size_t featureCount() const override;
     std::unique_ptr<GeometryTileFeature> getFeature(std::size_t i) const override;
@@ -49,9 +49,9 @@ private:
     mapbox::vector_tile::layer layer;
 };
 
-class VectorTileData : public GeometryTileData {
+class VectorMVTTileData : public GeometryTileData {
 public:
-    VectorTileData(std::shared_ptr<const std::string> data);
+    VectorMVTTileData(std::shared_ptr<const std::string> data);
 
     std::unique_ptr<GeometryTileData> clone() const override;
     std::unique_ptr<GeometryTileLayer> getLayer(const std::string& name) const override;

src/mbgl/tile/vector_tile.cpp

@@ -1,18 +1,19 @@
+#include <mbgl/tile/vector_mvt_tile.hpp>
+
 #include <mbgl/renderer/tile_parameters.hpp>
 #include <mbgl/tile/tile_loader_impl.hpp>
-#include <mbgl/tile/vector_tile.hpp>
-#include <mbgl/tile/vector_tile_data.hpp>
+
 #include <utility>
 
 namespace mbgl {
 
 VectorTile::VectorTile(const OverscaledTileID& id_,
                        std::string sourceID_,
-                       const TileParameters& parameters,
+                       const TileParameters& parameters_,
                        const Tileset& tileset,
                        TileObserver* observer_)
-    : GeometryTile(id_, std::move(sourceID_), parameters, observer_),
-      loader(*this, id_, parameters, tileset) {}
+    : GeometryTile(id_, std::move(sourceID_), parameters_, observer_),
+      loader(*this, id_, parameters_, tileset) {}
 
 VectorTile::~VectorTile() {
     // Don't rely on `~TileLoader` to close, it's not safe to call there.
@@ -33,12 +34,4 @@ void VectorTile::setMetadata(std::optional<Timestamp> modified_, std::optional<T
     expires = std::move(expires_);
 }
 
-void VectorTile::setData(const std::shared_ptr<const std::string>& data_) {
-    if (obsolete) {
-        return;
-    }
-
-    GeometryTile::setData(data_ ? std::make_unique<VectorTileData>(data_) : nullptr);
-}
-
 } // namespace mbgl

src/mbgl/tile/vector_tile.hpp

@@ -20,7 +20,8 @@ public:
     void setNecessity(TileNecessity) final;
     void setUpdateParameters(const TileUpdateParameters&) final;
     void setMetadata(std::optional<Timestamp> modified, std::optional<Timestamp> expires);
-    void setData(const std::shared_ptr<const std::string>& data);
+
+    virtual void setData(const std::shared_ptr<const std::string>&) = 0;
 
 private:
     TileLoader<VectorTile> loader;

test/CMakeLists.txt

@@ -52,7 +52,7 @@ add_library(
     ${PROJECT_SOURCE_DIR}/test/style/conversion/light.test.cpp
     ${PROJECT_SOURCE_DIR}/test/style/conversion/padding.test.cpp
     ${PROJECT_SOURCE_DIR}/test/style/conversion/property_value.test.cpp
-    ${PROJECT_SOURCE_DIR}/test/style/conversion/raster_dem_options.test.cpp
+    ${PROJECT_SOURCE_DIR}/test/style/conversion/source_options.test.cpp
     ${PROJECT_SOURCE_DIR}/test/style/conversion/stringify.test.cpp
     ${PROJECT_SOURCE_DIR}/test/style/conversion/tileset.test.cpp
     ${PROJECT_SOURCE_DIR}/test/style/expression/dependency.test.cpp

test/geometry/dem_data.test.cpp

@@ -17,7 +17,7 @@ auto fakeImage = [](Size s) {
 
 TEST(DEMData, ConstructorMapbox) {
     PremultipliedImage image = fakeImage({16, 16});
-    DEMData demdata(image, Tileset::DEMEncoding::Mapbox);
+    DEMData demdata(image, Tileset::RasterEncoding::Mapbox);
 
     EXPECT_EQ(demdata.dim, 16);
     EXPECT_EQ(demdata.stride, 18);
@@ -26,7 +26,7 @@ TEST(DEMData, ConstructorMapbox) {
 
 TEST(DEMData, ConstructorTerrarium) {
     PremultipliedImage image = fakeImage({16, 16});
-    DEMData demdata(image, Tileset::DEMEncoding::Terrarium);
+    DEMData demdata(image, Tileset::RasterEncoding::Terrarium);
 
     EXPECT_EQ(demdata.dim, 16);
     EXPECT_EQ(demdata.stride, 18);
@@ -35,7 +35,7 @@ TEST(DEMData, ConstructorTerrarium) {
 
 TEST(DEMData, InitialBackfill) {
     PremultipliedImage image1 = fakeImage({4, 4});
-    DEMData dem1(image1, Tileset::DEMEncoding::Mapbox);
+    DEMData dem1(image1, Tileset::RasterEncoding::Mapbox);
 
     bool nonempty = true;
     // checking that a 1 px border around the fake image has been populated
@@ -89,10 +89,10 @@ TEST(DEMData, InitialBackfill) {
 
 TEST(DEMData, BackfillNeighbor) {
     PremultipliedImage image1 = fakeImage({4, 4});
-    DEMData dem0(image1, Tileset::DEMEncoding::Mapbox);
+    DEMData dem0(image1, Tileset::RasterEncoding::Mapbox);
 
     PremultipliedImage image2 = fakeImage({4, 4});
-    DEMData dem1(image2, Tileset::DEMEncoding::Mapbox);
+    DEMData dem1(image2, Tileset::RasterEncoding::Mapbox);
 
     dem0.backfillBorder(dem1, -1, 0);
     for (int y = 0; y < 4; y++) {

test/style/conversion/raster_dem_options.test.cpp

@@ -1,48 +0,0 @@
-#include <mbgl/test/util.hpp>
-
-#include <mbgl/style/conversion/json.hpp>
-#include <mbgl/style/conversion/raster_dem_options.hpp>
-#include <mbgl/util/tileset.hpp>
-
-#include <mbgl/util/logging.hpp>
-
-using namespace mbgl;
-using namespace mbgl::style;
-using namespace mbgl::style::conversion;
-
-TEST(RasterDEMOptions, Basic) {
-    Error error;
-    std::optional<RasterDEMOptions> converted = convertJSON<RasterDEMOptions>("{}", error);
-    ASSERT_TRUE((bool)converted);
-}
-
-TEST(RasterDEMOptions, ErrorHandling) {
-    Error error;
-    std::optional<RasterDEMOptions> converted = convertJSON<RasterDEMOptions>(
-        R"JSON({
-        "encoding": "this isn't a valid encoding"
-    })JSON",
-        error);
-    ASSERT_FALSE(converted);
-    ASSERT_EQ(error.message, "invalid raster-dem encoding type - valid types are 'mapbox' and 'terrarium'");
-}
-
-TEST(RasterDEMOptions, TerrariumEncodingParsed) {
-    Error error;
-    std::optional<RasterDEMOptions> converted = convertJSON<RasterDEMOptions>(
-        R"JSON({
-        "encoding": "terrarium"
-    })JSON",
-        error);
-    ASSERT_EQ(converted.value().encoding, Tileset::DEMEncoding::Terrarium);
-}
-
-TEST(RasterDEMOptions, MapboxEncodingParsed) {
-    Error error;
-    std::optional<RasterDEMOptions> converted = convertJSON<RasterDEMOptions>(
-        R"JSON({
-        "encoding": "mapbox"
-    })JSON",
-        error);
-    ASSERT_EQ(converted.value().encoding, Tileset::DEMEncoding::Mapbox);
-}

test/style/conversion/source_options.test.cpp

@@ -0,0 +1,72 @@
+#include <mbgl/test/util.hpp>
+
+#include <mbgl/style/conversion/json.hpp>
+#include <mbgl/style/conversion/source_options.hpp>
+#include <mbgl/util/tileset.hpp>
+
+#include <mbgl/util/logging.hpp>
+
+using namespace mbgl;
+using namespace mbgl::style;
+using namespace mbgl::style::conversion;
+
+TEST(SourceOptions, Basic) {
+    Error error;
+    auto converted = convertJSON<SourceOptions>("{}", error);
+    ASSERT_FALSE(converted);
+}
+
+TEST(SourceOptions, ErrorHandling) {
+    Error error;
+    auto converted = convertJSON<SourceOptions>(
+        R"JSON({
+        "encoding": "this isn't a valid encoding"
+    })JSON",
+        error);
+    ASSERT_FALSE(converted);
+    ASSERT_EQ(0, error.message.find("invalid encoding"));
+}
+
+TEST(SourceOptions, TerrariumEncodingParsed) {
+    Error error;
+    auto converted = convertJSON<SourceOptions>(
+        R"JSON({
+        "encoding": "terrarium"
+    })JSON",
+        error);
+    ASSERT_EQ(converted.value().rasterEncoding, Tileset::RasterEncoding::Terrarium);
+    ASSERT_FALSE(converted.value().vectorEncoding);
+}
+
+TEST(SourceOptions, MapboxEncodingParsed) {
+    Error error;
+    auto converted = convertJSON<SourceOptions>(
+        R"JSON({
+        "encoding": "mapbox"
+    })JSON",
+        error);
+    ASSERT_EQ(converted.value().rasterEncoding, Tileset::RasterEncoding::Mapbox);
+    ASSERT_FALSE(converted.value().vectorEncoding);
+}
+
+TEST(SourceOptions, MVTEncodingParsed) {
+    Error error;
+    auto converted = convertJSON<SourceOptions>(
+        R"JSON({
+        "encoding": "mvt"
+    })JSON",
+        error);
+    ASSERT_EQ(converted.value().vectorEncoding, Tileset::VectorEncoding::Mapbox);
+    ASSERT_FALSE(converted.value().rasterEncoding);
+}
+
+TEST(SourceOptions, MLTEncodingParsed) {
+    Error error;
+    auto converted = convertJSON<SourceOptions>(
+        R"JSON({
+        "encoding": "mlt"
+    })JSON",
+        error);
+    ASSERT_EQ(converted.value().vectorEncoding, Tileset::VectorEncoding::MLT);
+    ASSERT_FALSE(converted.value().rasterEncoding);
+}

test/tile/raster_dem_tile.test.cpp

@@ -66,7 +66,7 @@ TEST(RasterDEMTile, onError) {
 TEST(RasterDEMTile, onParsed) {
     RasterDEMTileTest test;
     RasterDEMTile tile(OverscaledTileID(0, 0, 0), "testSource", test.tileParameters, test.tileset);
-    tile.onParsed(std::make_unique<HillshadeBucket>(PremultipliedImage({16, 16}), Tileset::DEMEncoding::Mapbox), 0);
+    tile.onParsed(std::make_unique<HillshadeBucket>(PremultipliedImage({16, 16}), Tileset::RasterEncoding::Mapbox), 0);
     EXPECT_TRUE(tile.isRenderable());
     EXPECT_TRUE(tile.isLoaded());
     EXPECT_TRUE(tile.isComplete());

test/tile/tile_cache.test.cpp

@@ -5,7 +5,7 @@
 #include <mbgl/test/fake_file_source.hpp>
 #include <mbgl/tile/tile_loader_impl.hpp>
 #include <mbgl/tile/vector_tile.hpp>
-#include <mbgl/tile/vector_tile_data.hpp>
+#include <mbgl/tile/vector_mvt_tile_data.hpp>
 
 #include <mbgl/actor/scheduler.hpp>
 #include <mbgl/annotation/annotation_manager.hpp>
@@ -38,6 +38,8 @@ public:
         renderable = true;
     }
 
+    void setData(const std::shared_ptr<const std::string>&) override {}
+
     util::SimpleIdentity uniqueId;
 };
 

test/tile/vector_tile.test.cpp

@@ -1,7 +1,7 @@
 #include <mbgl/test/util.hpp>
 #include <mbgl/test/fake_file_source.hpp>
-#include <mbgl/tile/vector_tile.hpp>
-#include <mbgl/tile/vector_tile_data.hpp>
+#include <mbgl/tile/vector_mvt_tile.hpp>
+#include <mbgl/tile/vector_mvt_tile_data.hpp>
 #include <mbgl/tile/tile_loader_impl.hpp>
 #include <mbgl/storage/resource_options.hpp>
 
@@ -25,7 +25,7 @@ using namespace mbgl;
 
 TEST(VectorTile, setError) {
     VectorTileTest test;
-    VectorTile tile(OverscaledTileID(0, 0, 0), "source", test.tileParameters, test.tileset);
+    VectorMVTTile tile(OverscaledTileID(0, 0, 0), "source", test.tileParameters, test.tileset);
     tile.setError(std::make_exception_ptr(std::runtime_error("test")));
     EXPECT_FALSE(tile.isRenderable());
     EXPECT_TRUE(tile.isLoaded());
@@ -34,7 +34,7 @@ TEST(VectorTile, setError) {
 
 TEST(VectorTile, onError) {
     VectorTileTest test;
-    VectorTile tile(OverscaledTileID(0, 0, 0), "source", test.tileParameters, test.tileset);
+    VectorMVTTile tile(OverscaledTileID(0, 0, 0), "source", test.tileParameters, test.tileset);
     tile.onError(std::make_exception_ptr(std::runtime_error("test")), 0);
 
     EXPECT_FALSE(tile.isRenderable());
@@ -44,7 +44,7 @@ TEST(VectorTile, onError) {
 
 TEST(VectorTile, Issue8542) {
     VectorTileTest test;
-    VectorTile tile(OverscaledTileID(0, 0, 0), "source", test.tileParameters, test.tileset);
+    VectorMVTTile tile(OverscaledTileID(0, 0, 0), "source", test.tileParameters, test.tileset);
 
     // Query before data is set
     std::vector<Feature> result;
@@ -52,7 +52,7 @@ TEST(VectorTile, Issue8542) {
 }
 
 TEST(VectorTileData, ParseResults) {
-    VectorTileData data(std::make_shared<std::string>(util::read_file("test/fixtures/map/issue12432/0-0-0.mvt")));
+    VectorMVTTileData data(std::make_shared<std::string>(util::read_file("test/fixtures/map/issue12432/0-0-0.mvt")));
 
     std::vector<std::string> layerNames = data.layerNames();
     ASSERT_EQ(layerNames.size(), 2u);

vendor/maplibre-tile-spec.cmake

@@ -0,0 +1,15 @@
+set(MLT_WITH_JSON OFF CACHE BOOL "No JSON support" FORCE)
+set(MLT_WITH_PROTOZERO OFF CACHE BOOL "No protozero" FORCE)
+set(MLT_WITH_FASTPFOR OFF CACHE BOOL "disabled for lack of support for ARMv7 in SIMDE and requirement for SSE on x86" FORCE)
+set(MLT_WITH_TESTS OFF CACHE BOOL "Google Test conflicts with Dawn")
+set(MLT_WITH_TOOLS OFF CACHE BOOL "Not used")
+
+# This is set by the platform CMakeLists.txt after vendor libraries.  If it was set earlier, we could just use it.
+set(CMAKE_OSX_DEPLOYMENT_TARGET 14.3)
+set(MLT_OSX_DEPLOYMENT_TARGET ${CMAKE_OSX_DEPLOYMENT_TARGET} CACHE STRING "Inherited MacOS/iOS target" FORCE)
+
+if (CMAKE_VERSION VERSION_GREATER_EQUAL "3.25")
+    add_subdirectory(${PROJECT_SOURCE_DIR}/vendor/maplibre-tile-spec/cpp SYSTEM)
+else()
+    add_subdirectory(${PROJECT_SOURCE_DIR}/vendor/maplibre-tile-spec/cpp)
+endif()