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#include <mbgl/actor/actor.hpp>
#include <mbgl/actor/scheduler.hpp>
#include <mbgl/sprite/sprite_loader.hpp>
#include <mbgl/sprite/sprite_loader_observer.hpp>
#include <mbgl/sprite/sprite_parser.hpp>
#include <mbgl/storage/file_source.hpp>
#include <mbgl/storage/resource.hpp>
#include <mbgl/storage/response.hpp>
#include <mbgl/util/async_request.hpp>
#include <mbgl/util/constants.hpp>
#include <mbgl/util/exception.hpp>
#include <mbgl/util/logging.hpp>
#include <mbgl/util/platform.hpp>
#include <mbgl/util/std.hpp>
#include <cassert>
namespace mbgl {
static SpriteLoaderObserver nullObserver;
struct SpriteLoader::Data {
std::shared_ptr<const std::string> image;
std::shared_ptr<const std::string> json;
std::unique_ptr<AsyncRequest> jsonRequest;
std::unique_ptr<AsyncRequest> spriteRequest;
};
SpriteLoader::SpriteLoader(float pixelRatio_)
: pixelRatio(pixelRatio_), observer(&nullObserver), threadPool(Scheduler::GetBackground()) {}
SpriteLoader::~SpriteLoader() = default;
void SpriteLoader::load(const std::string& url, FileSource& fileSource) {
if (url.empty()) {
// Treat a non-existent sprite as a successfully loaded empty sprite.
observer->onSpriteLoaded({});
return;
}
data = std::make_unique<Data>();
data->jsonRequest = fileSource.request(Resource::spriteJSON(url, pixelRatio), [this](Response res) {
if (res.error) {
observer->onSpriteError(std::make_exception_ptr(std::runtime_error(res.error->message)));
} else if (res.notModified) {
return;
} else if (res.noContent) {
data->json = std::make_shared<std::string>();
emitSpriteLoadedIfComplete();
} else {
// Only trigger a sprite loaded event we got new data.
assert(data->json != res.data);
data->json = std::move(res.data);
emitSpriteLoadedIfComplete();
}
});
data->spriteRequest = fileSource.request(Resource::spriteImage(url, pixelRatio), [this](Response res) {
if (res.error) {
observer->onSpriteError(std::make_exception_ptr(std::runtime_error(res.error->message)));
} else if (res.notModified) {
return;
} else if (res.noContent) {
data->image = std::make_shared<std::string>();
emitSpriteLoadedIfComplete();
} else {
assert(data->image != res.data);
data->image = std::move(res.data);
emitSpriteLoadedIfComplete();
}
});
}
void SpriteLoader::emitSpriteLoadedIfComplete() {
assert(data);
if (!data->image || !data->json) {
return;
}
struct ParseResult {
std::vector<Immutable<style::Image::Impl>> images;
std::exception_ptr error;
};
auto parseClosure = [image = data->image, json = data->json]() -> ParseResult {
try {
return {parseSprite(*image, *json), nullptr};
} catch (...) {
return {{}, std::current_exception()};
}
};
auto resultClosure = [this, weak = weakFactory.makeWeakPtr()](ParseResult result) {
if (!weak) return; // This instance has been deleted.
if (result.error) {
observer->onSpriteError(result.error);
return;
}
observer->onSpriteLoaded(std::move(result.images));
};
threadPool->scheduleAndReplyValue(parseClosure, resultClosure);
}
void SpriteLoader::setObserver(SpriteLoaderObserver* observer_) {
observer = observer_;
}
} // namespace mbgl
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