geojson_source.hpp

Go to the documentation of this file.

#pragma once
 
#include <mbgl/style/expression/expression.hpp>
#include <mbgl/style/source.hpp>
#include <mbgl/tile/tile_id.hpp>
#include <mbgl/util/constants.hpp>
#include <mbgl/util/geojson.hpp>
 
#include <map>
#include <memory>
#include <utility>
 
namespace mbgl {
 
class AsyncRequest;
class Scheduler;
namespace style {
 
struct GeoJSONOptions {
    // GeoJSON-VT options
    uint8_t minzoom = 0;
    uint8_t maxzoom = 18;
    uint16_t tileSize = util::tileSize_I;
    uint16_t buffer = 128;
    double tolerance = 0.375;
    bool lineMetrics = false;
 
    // Supercluster options
    bool cluster = false;
    uint16_t clusterRadius = 50;
    uint8_t clusterMaxZoom = 17;
    using ClusterExpression = std::pair<std::shared_ptr<mbgl::style::expression::Expression>,
                                        std::shared_ptr<mbgl::style::expression::Expression>>;
    using ClusterProperties = std::map<std::string, ClusterExpression>;
    ClusterProperties clusterProperties;
 
    static Immutable<GeoJSONOptions> defaultOptions();
};
class GeoJSONData {
public:
    using TileFeatures = mapbox::feature::feature_collection<int16_t>;
    using Features = mapbox::feature::feature_collection<double>;
    static std::shared_ptr<GeoJSONData> create(const GeoJSON&,
                                               const Immutable<GeoJSONOptions>& = GeoJSONOptions::defaultOptions(),
                                               std::shared_ptr<Scheduler> scheduler = nullptr);
 
    virtual ~GeoJSONData() = default;
    virtual void getTile(const CanonicalTileID&, const std::function<void(TileFeatures)>&) = 0;
 
    // SuperclusterData
    virtual Features getChildren(std::uint32_t) = 0;
    virtual Features getLeaves(std::uint32_t, std::uint32_t limit, std::uint32_t offset) = 0;
    virtual std::uint8_t getClusterExpansionZoom(std::uint32_t) = 0;
 
    virtual std::shared_ptr<Scheduler> getScheduler() { return nullptr; }
};
 
class GeoJSONSource final : public Source {
public:
    GeoJSONSource(std::string id, Immutable<GeoJSONOptions> = GeoJSONOptions::defaultOptions());
    ~GeoJSONSource() final;
 
    void setURL(const std::string& url);
    void setGeoJSON(const GeoJSON&);
    void setGeoJSONData(std::shared_ptr<GeoJSONData>);
 
    std::optional<std::string> getURL() const;
    const GeoJSONOptions& getOptions() const;
 
    class Impl;
    const Impl& impl() const;
 
    void loadDescription(FileSource&) final;
 
    bool supportsLayerType(const mbgl::style::LayerTypeInfo*) const override;
 
    mapbox::base::WeakPtr<Source> makeWeakPtr() override {
        return weakFactory.makeWeakPtr();
    }
 
protected:
    Mutable<Source::Impl> createMutable() const noexcept final;
 
private:
    std::optional<std::string> url;
    std::unique_ptr<AsyncRequest> req;
    std::shared_ptr<Scheduler> threadPool;
    mapbox::base::WeakPtrFactory<Source> weakFactory {this};
};
 
template <>
inline bool Source::is<GeoJSONSource>() const {
    return getType() == SourceType::GeoJSON;
}
 
} // namespace style
} // namespace mbgl