Mercurial > gemma
view pkg/imports/wkb.go @ 3678:8f58851927c0
client: make layer factory only return new layer config for individual maps
instead of each time it is invoked. The purpose of the factory was to support multiple maps with individual layers.
But returning a new config each time it is invoked leads to bugs that rely on the layer's state. Now this factory
reuses the same objects it created before, per map.
author | Markus Kottlaender <markus@intevation.de> |
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date | Mon, 17 Jun 2019 17:31:35 +0200 |
parents | 63475c8e710e |
children | 8b75ac5e243e |
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// This is Free Software under GNU Affero General Public License v >= 3.0 // without warranty, see README.md and license for details. // // SPDX-License-Identifier: AGPL-3.0-or-later // License-Filename: LICENSES/AGPL-3.0.txt // // Copyright (C) 2018 by via donau // – Österreichische Wasserstraßen-Gesellschaft mbH // Software engineering by Intevation GmbH // // Author(s): // * Sascha L. Teichmann <sascha.teichmann@intevation.de> package imports import ( "bytes" "encoding/binary" "fmt" "math" shp "github.com/jonas-p/go-shp" "gemma.intevation.de/gemma/pkg/wkb" ) type ( pointSlice []float64 lineSlice [][]float64 polygonSlice [][][]float64 ) func (l lineSlice) asWKB() []byte { size := 1 + 4 + 4 + len(l)*(2*8) buf := bytes.NewBuffer(make([]byte, 0, size)) binary.Write(buf, binary.LittleEndian, wkb.NDR) binary.Write(buf, binary.LittleEndian, wkb.LineString) binary.Write(buf, binary.LittleEndian, uint32(len(l))) for _, c := range l { var lat, lon float64 if len(c) > 0 { lat = c[0] } if len(c) > 1 { lon = c[1] } binary.Write(buf, binary.LittleEndian, math.Float64bits(lat)) binary.Write(buf, binary.LittleEndian, math.Float64bits(lon)) } return buf.Bytes() } func (p pointSlice) asWKB() []byte { size := 1 + 4 + 2*8 buf := bytes.NewBuffer(make([]byte, 0, size)) binary.Write(buf, binary.LittleEndian, wkb.NDR) binary.Write(buf, binary.LittleEndian, wkb.Point) var lat, lon float64 if len(p) > 0 { lat = p[0] } if len(p) > 1 { lon = p[1] } binary.Write(buf, binary.LittleEndian, math.Float64bits(lat)) binary.Write(buf, binary.LittleEndian, math.Float64bits(lon)) return buf.Bytes() } func (p polygonSlice) asWKB() []byte { if p == nil { return nil } // pre-calculate size to avoid reallocations. size := 1 + 4 + 4 for _, ring := range p { size += 4 + len(ring)*2*8 } buf := bytes.NewBuffer(make([]byte, 0, size)) binary.Write(buf, binary.LittleEndian, wkb.NDR) binary.Write(buf, binary.LittleEndian, wkb.Polygon) binary.Write(buf, binary.LittleEndian, uint32(len(p))) for _, ring := range p { binary.Write(buf, binary.LittleEndian, uint32(len(ring))) for _, v := range ring { var lat, lon float64 if len(v) > 0 { lat = v[0] } if len(v) > 1 { lon = v[1] } binary.Write(buf, binary.LittleEndian, math.Float64bits(lat)) binary.Write(buf, binary.LittleEndian, math.Float64bits(lon)) } } return buf.Bytes() } func shapeToPolygon(s shp.Shape) (polygonSlice, error) { switch p := s.(type) { case *shp.Polygon: return toPolygon(p.NumParts, p.Parts, p.Points), nil case *shp.PolygonZ: return toPolygon(p.NumParts, p.Parts, p.Points), nil case *shp.PolygonM: return toPolygon(p.NumParts, p.Parts, p.Points), nil } return nil, fmt.Errorf("Unsupported shape type %T", s) } func toPolygon(numParts int32, parts []int32, points []shp.Point) polygonSlice { out := make(polygonSlice, numParts) var pos int32 for i := range out { var howMany int32 if i+1 >= len(parts) { howMany = int32(len(points)) - pos } else { howMany = parts[i+1] - parts[i] } line := make([][]float64, howMany) vertices := make([]float64, 2*howMany) for j := int32(0); j < howMany; j, pos = j+1, pos+1 { p := &points[pos] vertex := vertices[j*2 : j*2+2] vertex[0], vertex[1] = p.X, p.Y line[j] = vertex } out[i] = line } return out }