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#include <mbgl/map/vector_tile.hpp>
#include <mbgl/style/filter_expression_private.hpp>
#include <mbgl/util/variant_io.hpp>
#include <algorithm>
#include <iostream>
using namespace mbgl;
std::ostream& mbgl::operator<<(std::ostream& os, const FeatureType& type) {
switch (type) {
case FeatureType::Unknown: return os << "Unknown";
case FeatureType::Point: return os << "Point";
case FeatureType::LineString: return os << "LineString";
case FeatureType::Polygon: return os << "Polygon";
default: return os << "Invalid";
}
}
VectorTileFeature::VectorTileFeature(pbf feature, const VectorTileLayer& layer) {
while (feature.next()) {
if (feature.tag == 1) { // id
id = feature.varint<uint64_t>();
} else if (feature.tag == 2) { // tags
// tags are packed varints. They should have an even length.
pbf tags = feature.message();
while (tags) {
uint32_t tag_key = tags.varint();
if (layer.keys.size() <= tag_key) {
throw std::runtime_error("feature referenced out of range key");
}
if (tags) {
uint32_t tag_val = tags.varint();
if (layer.values.size() <= tag_val) {
throw std::runtime_error("feature referenced out of range value");
}
properties.emplace(layer.keys[tag_key], layer.values[tag_val]);
} else {
throw std::runtime_error("uneven number of feature tag ids");
}
}
} else if (feature.tag == 3) { // type
type = (FeatureType)feature.varint();
} else if (feature.tag == 4) { // geometry
geometry = feature.message();
} else {
feature.skip();
}
}
}
std::ostream& mbgl::operator<<(std::ostream& os, const VectorTileFeature& feature) {
os << "Feature(" << feature.id << "): " << feature.type << std::endl;
for (const auto& prop : feature.properties) {
os << " - " << prop.first << ": " << prop.second << std::endl;
}
return os;
}
VectorTile::VectorTile() {}
VectorTile::VectorTile(pbf tile) {
while (tile.next()) {
if (tile.tag == 3) { // layer
VectorTileLayer layer(tile.message());
layers.emplace(layer.name, std::forward<VectorTileLayer>(layer));
} else {
tile.skip();
}
}
}
VectorTile& VectorTile::operator=(VectorTile && other) {
if (this != &other) {
layers.swap(other.layers);
}
return *this;
}
VectorTileLayer::VectorTileLayer(pbf layer) : data(layer) {
std::vector<std::string> stacks;
while (layer.next()) {
if (layer.tag == 1) { // name
name = layer.string();
} else if (layer.tag == 3) { // keys
keys.emplace_back(layer.string());
key_index.emplace(keys.back(), keys.size() - 1);
} else if (layer.tag == 4) { // values
values.emplace_back(std::move(parseValue(layer.message())));
} else if (layer.tag == 5) { // extent
extent = layer.varint();
} else {
layer.skip();
}
}
}
FilteredVectorTileLayer::FilteredVectorTileLayer(const VectorTileLayer& layer_, const FilterExpression &filterExpression_)
: layer(layer_),
filterExpression(filterExpression_) {
}
FilteredVectorTileLayer::iterator FilteredVectorTileLayer::begin() const {
return iterator(*this, layer.data);
}
FilteredVectorTileLayer::iterator FilteredVectorTileLayer::end() const {
return iterator(*this, pbf(layer.data.end, 0));
}
FilteredVectorTileLayer::iterator::iterator(const FilteredVectorTileLayer& parent_, const pbf& data_)
: parent(parent_),
feature(pbf()),
data(data_) {
operator++();
}
VectorTileTagExtractor::VectorTileTagExtractor(const VectorTileLayer &layer) : layer_(layer) {}
void VectorTileTagExtractor::setTags(const pbf &pbf) {
tags_ = pbf;
}
mapbox::util::optional<Value> VectorTileTagExtractor::getValue(const std::string &key) const {
if (key == "$type") {
return Value(uint64_t(type_));
}
mapbox::util::optional<Value> value;
auto field_it = layer_.key_index.find(key);
if (field_it != layer_.key_index.end()) {
const uint32_t filter_key = field_it->second;
// Now loop through all the key/value pair tags.
// tags are packed varints. They should have an even length.
pbf tags_pbf = tags_;
uint32_t tag_key, tag_val;
while (tags_pbf) {
tag_key = tags_pbf.varint();
if (!tags_pbf) {
// This should not happen; otherwise the vector tile is invalid.
fprintf(stderr, "[WARNING] uneven number of feature tag ids\n");
return value;
}
// Note: We need to run this command in all cases, even if the keys don't match.
tag_val = tags_pbf.varint();
if (tag_key == filter_key) {
if (layer_.values.size() > tag_val) {
value = layer_.values[tag_val];
} else {
fprintf(stderr, "[WARNING] feature references out of range value\n");
break;
}
}
}
}
return value;
}
void VectorTileTagExtractor::setType(FeatureType type) {
type_ = type;
}
template bool mbgl::evaluate(const FilterExpression&, const VectorTileTagExtractor&);
void FilteredVectorTileLayer::iterator::operator++() {
valid = false;
const FilterExpression &expression = parent.filterExpression;
while (data.next(2)) { // feature
feature = data.message();
pbf feature_pbf = feature;
VectorTileTagExtractor extractor(parent.layer);
// Retrieve the basic information
while (feature_pbf.next()) {
if (feature_pbf.tag == 2) { // tags
extractor.setTags(feature_pbf.message());
} else if (feature_pbf.tag == 3) { // geometry type
extractor.setType(FeatureType(feature_pbf.varint()));
} else {
feature_pbf.skip();
}
}
if (evaluate(expression, extractor)) {
valid = true;
return; // data loop
} else {
valid = false;
}
}
}
bool FilteredVectorTileLayer::iterator::operator!=(const iterator& other) const {
return !(data.data == other.data.data && data.end == other.data.end && valid == other.valid);
}
const pbf& FilteredVectorTileLayer::iterator:: operator*() const {
return feature;
}
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