func geosPolygon(g *geos.Geos, polygon geojson.Polygon) (*geos.Geom, error) {
if len(polygon) == 0 {
return nil, errors.New("empty polygon")
}
shell, err := geosRing(g, polygon[0])
if err != nil {
return nil, err
}
holes := make([]*geos.Geom, len(polygon)-1)
for i, ls := range polygon[1:] {
hole, err := geosRing(g, ls)
if err != nil {
return nil, err
}
holes[i] = hole
}
geom := g.Polygon(shell, holes)
if geom == nil {
g.Destroy(shell)
for _, hole := range holes {
g.Destroy(hole)
}
return nil, errors.New("unable to create polygon")
}
return geom, nil
}
func splitPolygonAtGrid(g *geos.Geos, geom *geos.Geom, gridWidth, currentGridWidth float64) ([]*geos.Geom, error) {
var result []*geos.Geom
geomBounds := geom.Bounds()
if geomBounds == geos.NilBounds {
return nil, errors.New("couldn't create bounds for geom")
}
for _, bounds := range tileBounds(geom.Bounds(), currentGridWidth) {
clipGeom := g.BoundsPolygon(bounds)
if clipGeom == nil {
return nil, errors.New("couldn't create bounds polygon")
}
part := g.Intersection(geom, clipGeom)
g.Destroy(clipGeom)
if part == nil {
return nil, errors.New("couldn't create intersection")
}
if !g.IsEmpty(part) && strings.HasSuffix(g.Type(part), "Polygon") {
if gridWidth >= currentGridWidth {
result = append(result, part)
} else {
moreParts, err := splitPolygonAtGrid(g, part, gridWidth, currentGridWidth/2.0)
g.Destroy(part)
if err != nil {
return nil, err
}
result = append(result, moreParts...)
}
}
}
return result, nil
}
func Polygon(g *geos.Geos, nodes []element.Node) (*geos.Geom, error) {
nodes = unduplicateNodes(nodes)
if len(nodes) < 4 {
return nil, ErrorNoRing
}
coordSeq, err := g.CreateCoordSeq(uint32(len(nodes)), 2)
if err != nil {
return nil, err
}
// coordSeq inherited by LinearRing, no destroy
for i, nd := range nodes {
err := coordSeq.SetXY(g, uint32(i), nd.Long, nd.Lat)
if err != nil {
return nil, err
}
}
ring, err := coordSeq.AsLinearRing(g)
if err != nil {
// coordSeq gets Destroy by GEOS
return nil, err
}
// ring inherited by Polygon, no destroy
geom := g.Polygon(ring, nil)
if geom == nil {
g.Destroy(ring)
return nil, errors.New("unable to create polygon")
}
g.DestroyLater(geom)
return geom, nil
}
func destroyRings(g *geos.Geos, rings []*Ring) {
for _, r := range rings {
if r.geom != nil {
g.Destroy(r.geom)
r.geom = nil
}
}
}
func filterInvalidLineStrings(g *geos.Geos, geoms []*geos.Geom) []*geos.Geom {
var result []*geos.Geom
for _, geom := range geoms {
if geom.Length() > 1e-9 {
result = append(result, geom)
} else {
g.Destroy(geom)
}
}
return result
}
func flattenLineStrings(g *geos.Geos, geoms []*geos.Geom) []*geos.Geom {
var result []*geos.Geom
for _, geom := range geoms {
if g.Type(geom) == "MultiLineString" {
for _, part := range g.Geoms(geom) {
result = append(result, g.Clone(part))
}
g.Destroy(geom)
} else if g.Type(geom) == "LineString" {
result = append(result, geom)
} else {
log.Printf("unexpected geometry type in flattenLineStrings: %s", g.Type(geom))
g.Destroy(geom)
}
}
return result
}
// IntersectsBuffer returns true if the point (EPSG:4326) intersects the buffered
// LimitTo geometry.
func (c *Limiter) IntersectsBuffer(g *geos.Geos, x, y float64) bool {
if c.bufferedPrep == nil {
return true
}
if x < c.bufferedBbox.MinX ||
y < c.bufferedBbox.MinY ||
x > c.bufferedBbox.MaxX ||
y > c.bufferedBbox.MaxY {
return false
}
p := g.Point(x, y)
if p == nil {
return false
}
defer g.Destroy(p)
c.bufferedPrepMu.Lock()
defer c.bufferedPrepMu.Unlock()
return g.PreparedIntersects(c.bufferedPrep, p)
}
func filterGeometryByType(g *geos.Geos, geom *geos.Geom, targetType string) []*geos.Geom {
// Filter (multi)geometry for compatible `geom_type`,
// because we can't insert points into linestring tables for example
geomType := g.Type(geom)
if geomType == targetType {
// same type is fine
return []*geos.Geom{geom}
}
if geomType == "Polygon" && targetType == "MultiPolygon" {
// multipolygon mappings also support polygons
return []*geos.Geom{geom}
}
if geomType == "MultiPolygon" && targetType == "Polygon" {
// polygon mappings should also support multipolygons
return []*geos.Geom{geom}
}
if g.NumGeoms(geom) >= 1 {
// GeometryCollection or MultiLineString? return list of geometries
var geoms []*geos.Geom
for _, part := range g.Geoms(geom) {
// only parts with same type
if g.Type(part) == targetType {
geoms = append(geoms, g.Clone(part))
}
}
g.Destroy(geom)
if len(geoms) != 0 {
return geoms
}
return []*geos.Geom{}
}
g.Destroy(geom)
return []*geos.Geom{}
}
// buildRelGeometry builds the geometry of rel by creating a multipolygon of all rings.
// rings need to be sorted by area (large to small).
func buildRelGeometry(g *geos.Geos, rel *element.Relation, rings []*ring) (*geos.Geom, error) {
totalRings := len(rings)
shells := map[*ring]bool{rings[0]: true}
for i := 0; i < totalRings; i++ {
testGeom := g.Prepare(rings[i].geom)
if testGeom == nil {
return nil, errors.New("Error while preparing geometry")
}
for j := i + 1; j < totalRings; j++ {
if g.PreparedContains(testGeom, rings[j].geom) {
if rings[j].containedBy != -1 {
// j is inside a larger ring, remove that relationship
// e.g. j is hole inside a hole (i)
delete(rings[rings[j].containedBy].holes, rings[j])
delete(shells, rings[j])
}
// remember parent
rings[j].containedBy = i
// add ring as hole or shell
if ringIsHole(rings, j) {
rings[i].holes[rings[j]] = true
rings[i].outer = false
} else {
shells[rings[j]] = true
rings[i].outer = true
}
}
}
if rings[i].containedBy == -1 {
// add as shell if it is not a hole
shells[rings[i]] = true
rings[i].outer = true
}
g.PreparedDestroy(testGeom)
}
var polygons []*geos.Geom
for shell, _ := range shells {
var interiors []*geos.Geom
for hole, _ := range shell.holes {
ring := g.Clone(g.ExteriorRing(hole.geom))
g.Destroy(hole.geom)
if ring == nil {
return nil, errors.New("Error while getting exterior ring.")
}
interiors = append(interiors, ring)
}
exterior := g.Clone(g.ExteriorRing(shell.geom))
g.Destroy(shell.geom)
if exterior == nil {
return nil, errors.New("Error while getting exterior ring.")
}
polygon := g.Polygon(exterior, interiors)
if polygon == nil {
return nil, errors.New("Error while building polygon.")
}
polygons = append(polygons, polygon)
}
var result *geos.Geom
if len(polygons) == 1 {
result = polygons[0]
} else {
result = g.MultiPolygon(polygons)
if result == nil {
return nil, errors.New("Error while building multi-polygon.")
}
}
var err error
result, err = g.MakeValid(result)
if err != nil {
return nil, err
}
g.DestroyLater(result)
outer := make(map[int64]struct{})
for i := range rings {
if rings[i].outer {
for _, w := range rings[i].ways {
outer[w.Id] = struct{}{}
}
}
}
for i := range rel.Members {
mid := rel.Members[i].Id
if _, ok := outer[mid]; ok {
rel.Members[i].Role = "outer"
} else {
rel.Members[i].Role = "inner"
}
}
return result, nil
}
func handleMultiPolygon(rw *RelationWriter, r *element.Relation, geos *geosp.Geos) bool {
// prepare relation first (build rings and compute actual
// relation tags)
prepedRel, err := geomp.PrepareRelation(r, rw.srid, rw.maxGap)
if err != nil {
if errl, ok := err.(ErrorLevel); !ok || errl.Level() > 0 {
log.Warn(err)
}
return false
}
// check for matches befor building the geometry
matches := rw.polygonMatcher.MatchRelation(r)
if matches == nil {
return false
}
// build the multipolygon
geom, err := prepedRel.Build()
if geom.Geom != nil {
defer geos.Destroy(geom.Geom)
}
if err != nil {
if errl, ok := err.(ErrorLevel); !ok || errl.Level() > 0 {
log.Warn(err)
}
return false
}
if rw.limiter != nil {
start := time.Now()
parts, err := rw.limiter.Clip(geom.Geom)
if err != nil {
log.Warn(err)
return false
}
if duration := time.Now().Sub(start); duration > time.Minute {
log.Warnf("clipping relation %d to -limitto took %s", r.Id, duration)
}
for _, g := range parts {
rel := element.Relation(*r)
rel.Id = rw.relId(r.Id)
geom = geomp.Geometry{Geom: g, Wkb: geos.AsEwkbHex(g)}
err := rw.inserter.InsertPolygon(rel.OSMElem, geom, matches)
if err != nil {
if errl, ok := err.(ErrorLevel); !ok || errl.Level() > 0 {
log.Warn(err)
}
continue
}
}
} else {
rel := element.Relation(*r)
rel.Id = rw.relId(r.Id)
err := rw.inserter.InsertPolygon(rel.OSMElem, geom, matches)
if err != nil {
if errl, ok := err.(ErrorLevel); !ok || errl.Level() > 0 {
log.Warn(err)
}
return false
}
}
for _, m := range mapping.SelectRelationPolygons(rw.polygonMatcher, r) {
err = rw.osmCache.InsertedWays.PutWay(m.Way)
if err != nil {
log.Warn(err)
}
}
return true
}