optional<Function<T>> parseFunction(const char* name, const JSValue& value) {
if (!value.IsObject()) {
auto constant = parseProperty<T>(name, value);
if (!constant) {
return {};
}
return { Function<T>(*constant) };
}
if (!value.HasMember("stops")) {
Log::Warning(Event::ParseStyle, "function must specify a function type");
return {};
}
float base = 1.0f;
if (value.HasMember("base")) {
const JSValue& value_base = value["base"];
if (!value_base.IsNumber()) {
Log::Warning(Event::ParseStyle, "base must be numeric");
return {};
}
base = value_base.GetDouble();
}
auto stops = parseStops<T>(name, value["stops"]);
if (!stops) {
return {};
}
return { Function<T>(*stops, base) };
}
optional<PropertyTransition> parseProperty(const char *, const JSValue& value) {
PropertyTransition transition;
if (value.IsObject()) {
bool parsed = false;
if (value.HasMember("duration") && value["duration"].IsNumber()) {
transition.duration.emplace(Milliseconds(value["duration"].GetUint()));
parsed = true;
}
if (value.HasMember("delay") && value["delay"].IsNumber()) {
transition.delay.emplace(Milliseconds(value["delay"].GetUint()));
parsed = true;
}
if (!parsed) {
return {};
}
}
return transition;
}
optional<TransitionOptions> parseTransitionOptions(const char *, const JSValue& value) {
if (!value.IsObject()) {
return {};
}
optional<Duration> duration;
if (value.HasMember("duration") && value["duration"].IsNumber()) {
duration.emplace(Milliseconds(value["duration"].GetUint()));
}
optional<Duration> delay;
if (value.HasMember("delay") && value["delay"].IsNumber()) {
delay.emplace(Milliseconds(value["delay"].GetUint()));
}
if (!duration && !delay) {
return {};
}
return TransitionOptions(duration, delay);
}
void Parser::parseLayer(const std::string& id, const JSValue& value, std::unique_ptr<Layer>& layer) {
if (layer) {
// Skip parsing this again. We already have a valid layer definition.
return;
}
// Make sure we have not previously attempted to parse this layer.
if (std::find(stack.begin(), stack.end(), id) != stack.end()) {
Log::Warning(Event::ParseStyle, "layer reference of '%s' is circular", id.c_str());
return;
}
if (value.HasMember("ref")) {
// This layer is referencing another layer. Recursively parse that layer.
const JSValue& refVal = value["ref"];
if (!refVal.IsString()) {
Log::Warning(Event::ParseStyle, "layer ref of '%s' must be a string", id.c_str());
return;
}
const std::string ref { refVal.GetString(), refVal.GetStringLength() };
auto it = layersMap.find(ref);
if (it == layersMap.end()) {
Log::Warning(Event::ParseStyle, "layer '%s' references unknown layer %s", id.c_str(), ref.c_str());
return;
}
// Recursively parse the referenced layer.
stack.push_front(id);
parseLayer(it->first,
it->second.first,
it->second.second);
stack.pop_front();
Layer* reference = it->second.second.get();
if (!reference) {
return;
}
layer = reference->cloneRef(id);
conversion::setPaintProperties(*layer, value);
} else {
conversion::Error error;
optional<std::unique_ptr<Layer>> converted = conversion::convert<std::unique_ptr<Layer>>(value, error);
if (!converted) {
Log::Warning(Event::ParseStyle, error.message);
return;
}
layer = std::move(*converted);
}
}
optional<Function<Faded<T>>> parseFadedFunction(const JSValue& value) {
if (!value.HasMember("stops")) {
Log::Warning(Event::ParseStyle, "function must specify a function type");
return {};
}
auto stops = parseStops<T>("", value["stops"]);
if (!stops) {
return {};
}
return Function<Faded<T>>(*stops);
}
std::unique_ptr<RasterSource> RasterSource::parse(std::string id, const JSValue& value) {
optional<variant<std::string, Tileset>> urlOrTileset = TileSource::parseURLOrTileset(value);
if (!urlOrTileset) {
return nullptr;
}
uint16_t tileSize = util::tileSize;
if (value.HasMember("tileSize")) {
const JSValue& tileSizeVal = value["tileSize"];
if (tileSizeVal.IsNumber() && tileSizeVal.GetUint64() <= std::numeric_limits<uint16_t>::max()) {
tileSize = tileSizeVal.GetUint64();
} else {
Log::Error(Event::ParseStyle, "invalid tileSize");
return nullptr;
}
}
return std::make_unique<RasterSource>(std::move(id), std::move(*urlOrTileset), tileSize);
}