Convert

Convert holds several golang tools used to convert csv, postgres json, and geojson into MineAR (Unity) - style json.

This tool is a replicate of the pkg by same name within MineAR's admin utility, and heavily used by Map.Life's dataman utility.

The output is a Datasets struct, which can hold any number of features (points, lines, and shapes), and attributes for each feature.

The final Datasets struct must be json-marshaled prior to use in MineAR.

Note: this package spawns a unique channel & goroutine for each dataset processed, called an ExtentContainer. The purpose of this is to asynchronously handle coordinates, figure out which four form the bottom-left and top-right of the enclosing bounding box bbox (aka Extent). The container uses the bbox to populate the s2 cell array and also find the center point.

Primary Functions

DatasetFromCSV(xField string, yField string, zField string, contents io.Reader) (*Datasets, error)

Converts a CSV (with x and y specified, and z if known) to a Datasets struct.

DatasetFromGEOJSON("", "", "", "", contents io.Reader) (*Datasets, error)

Converts a GEOJSON and any attributes! to a Datasets struct.

DatasetFromKML("", "", "", "", contents io.Reader) (*Datasets, error)

Converts a KML and extended attributes! to a Datasets struct.

DatasetFromGPX("", "", "", "", contents io.Reader) (*Datasets, error)

Converts a GPX and extended attributes! to a Datasets struct.

parseGEOJSONCollection(collection *geojson.FeatureCollection, container *ExtentContainer) (*Datasets, error)

Takes a GEOJSON- which are always 'feature collections', and breaks it up into features. Depends on ParseGEOJSONFeature. Uses the intermediate FeatureInfo struct as a map between the geojson itself and the new Datasets which holds n count of Features of type FeatureInfo. You should not call this function directly, but rather DatasetFromGEOJSON or, if you have individual features, ParseGEOJSONFeature.

ParseGEOJSONFeature(gfeature *convert.FeatureInfo, outdataset *convert.Datasets, nil)

Converts each feature json into a FeatureInfo class, parsing both the attributes of the originating geojson and the geom of the originating geom.

ParseNestedGeom

Explodes an n depth slice geometry, uses GetElev to fill in Z value, and enforces EPSG:3857. Used by GeoJSON, KML, and GPX conversion.

ParseGEOJSONAttributes

Explodes the feature attributes, maps name, styletype, and id to a higher object level in the FeatureInfo, removes attributes with missing/nil values (keeping the resulting Unity json as trim as possible), and moves all cleaned key:value attribute pairs to the new FeatureInfo.

Secondary Functions

GetElev(x float64, y float64) (float64, error)

Takes x and y, provides a single elevation in meters Depends upon To4326

To4326(x float64, y float64) (float64, float64)

Takes x and y, provides x and y in EPSG:4326 (lat lon decimal)

To3857((x float64, y float64) (float64, float64)

Takes x and y, provides x and y in EPSG:3847 (universal web mercator)