Files
MapLibreParticleLab/include/mbgl/style/source.hpp
John Firebaugh afead4e749 [core] Return {Source,Layer}::getID by value
Avoid dangling references in the following sequence:

    auto& id = layer->getID();
    layer->setMaxZoom(2);
    std::cout << id;

The reference would be dangling because mutating the layer allocates a new Immutable impl, and there may be no references to the prior impl, which held the id.
2017-05-12 11:26:27 -07:00

84 lines
2.2 KiB
C++

#pragma once
#include <mbgl/util/noncopyable.hpp>
#include <mbgl/util/optional.hpp>
#include <mbgl/util/any.hpp>
#include <mbgl/util/immutable.hpp>
#include <mbgl/style/types.hpp>
#include <memory>
#include <string>
namespace mbgl {
class FileSource;
namespace style {
class VectorSource;
class RasterSource;
class GeoJSONSource;
class SourceObserver;
/**
* The runtime representation of a [source](https://www.mapbox.com/mapbox-gl-style-spec/#sources) from the Mapbox Style
* Specification.
*
* `Source` is an abstract base class; concrete derived classes are provided for each source type. `Source` contains
* functionality that is common to all layer types:
*
* * Runtime type information: type predicates and casting
* * Accessors for properties common to all source types: ID, etc.
* * Cloning and copying
*
* All other functionality lives in the derived classes. To instantiate a source, create an instance of the desired
* type, passing the ID:
*
* auto vectorSource = std::make_unique<VectorSource>("my-vector-source");
*/
class Source : public mbgl::util::noncopyable {
public:
virtual ~Source();
// Check whether this source is of the given subtype.
template <class T>
bool is() const;
// Dynamically cast this source to the given subtype.
template <class T>
T* as() {
return is<T>() ? reinterpret_cast<T*>(this) : nullptr;
}
template <class T>
const T* as() const {
return is<T>() ? reinterpret_cast<const T*>(this) : nullptr;
}
SourceType getType() const;
std::string getID() const;
optional<std::string> getAttribution() const;
// Private implementation
class Impl;
Immutable<Impl> baseImpl;
Source(Immutable<Impl>);
void setObserver(SourceObserver*);
SourceObserver* observer = nullptr;
virtual void loadDescription(FileSource&) = 0;
void dumpDebugLogs() const;
bool loaded = false;
// For use in SDK bindings, which store a reference to a platform-native peer
// object here, so that separately-obtained references to this object share
// identical platform-native peers.
any peer;
};
} // namespace style
} // namespace mbgl