Tile::Tile(TileID _id, const MapProjection& _projection, const DataSource* _source) :
m_id(_id),
m_projection(&_projection),
m_sourceId(_source ? _source->id() : 0),
m_sourceGeneration(_source ? _source->generation() : 0) {
BoundingBox bounds(_projection.TileBounds(_id));
m_scale = bounds.width();
m_inverseScale = 1.0/m_scale;
updateTileOrigin(_id.wrap);
// Init model matrix to size of tile
m_modelMatrix = glm::scale(glm::mat4(1.0), glm::vec3(m_scale));
}
MapTile::MapTile(TileID _id, const MapProjection& _projection) : m_id(_id), m_projection(&_projection) {
glm::dvec4 bounds = _projection.TileBounds(_id); // [x: xmin, y: ymin, z: xmax, w: ymax]
m_scale = 0.5 * glm::abs(bounds.x - bounds.z);
m_inverseScale = 1.0/m_scale;
// negative y coordinate: to change from y down to y up (tile system has y down and gl context we use has y up).
m_tileOrigin = glm::dvec2(0.5*(bounds.x + bounds.z), -0.5*(bounds.y + bounds.w));
m_modelMatrix = glm::mat4(1.0);
// Scale model matrix to size of tile
m_modelMatrix = glm::scale(m_modelMatrix, glm::vec3(m_scale));
}
std::shared_ptr<TileData> TopoJsonSource::parse(const TileTask& _task,
const MapProjection& _projection) const {
auto& task = static_cast<const DownloadTileTask&>(_task);
std::shared_ptr<TileData> tileData = std::make_shared<TileData>();
// Parse data into a JSON document
const char* error;
size_t offset;
auto document = JsonParseBytes(task.rawTileData->data(), task.rawTileData->size(), &error, &offset);
if (error) {
LOGE("Json parsing failed on tile [%s]: %s (%u)", task.tileId().toString().c_str(), error, offset);
return tileData;
}
// Transform JSON data into a TileData using TopoJson functions
BoundingBox tileBounds(_projection.TileBounds(task.tileId()));
glm::dvec2 tileOrigin = {tileBounds.min.x, tileBounds.max.y*-1.0};
double tileInverseScale = 1.0 / tileBounds.width();
const auto projFn = [&](glm::dvec2 _lonLat){
glm::dvec2 tmp = _projection.LonLatToMeters(_lonLat);
return Point {
(tmp.x - tileOrigin.x) * tileInverseScale,
(tmp.y - tileOrigin.y) * tileInverseScale,
0
};
};
// Parse topology and transform
auto topology = TopoJson::getTopology(document, projFn);
// Parse each TopoJson object as a data layer
auto objectsIt = document.FindMember("objects");
if (objectsIt == document.MemberEnd()) { return tileData; }
auto& objects = objectsIt->value;
for (auto layer = objects.MemberBegin(); layer != objects.MemberEnd(); ++layer) {
tileData->layers.push_back(TopoJson::getLayer(layer, topology, m_id));
}
// Discard JSON object and return TileData
return tileData;
}
Tile::Tile(TileID _id, const MapProjection& _projection) :
m_id(_id),
m_projection(&_projection),
m_visible(false),
m_priority(0) {
BoundingBox bounds(_projection.TileBounds(_id));
m_scale = 0.5 * bounds.width();
m_inverseScale = 1.0/m_scale;
m_tileOrigin = bounds.center();
// negative y coordinate: to change from y down to y up (tile system has y down and gl context we use has y up).
m_tileOrigin.y *= -1.0;
// Init model matrix to size of tile
m_modelMatrix = glm::scale(glm::mat4(1.0), glm::vec3(m_scale));
}
