Mercurial > gemma
view pkg/mesh/loader.go @ 5520:05db984d3db1
Improve performance of bottleneck area calculation
Avoid buffer calculations by replacing them with simple distance comparisons
and calculate the boundary of the result geometry only once per iteration.
In some edge cases with very large numbers of iterations, this reduced
the runtime of a bottleneck import by a factor of more than twenty.
author | Tom Gottfried <tom@intevation.de> |
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date | Thu, 21 Oct 2021 19:50:39 +0200 |
parents | 5f47eeea988d |
children | 1222b777f51f |
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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 mesh import ( "bufio" "bytes" "compress/gzip" "encoding/binary" "gemma.intevation.de/gemma/pkg/log" ) func (s *STRTree) deserializeIndex(r *bufio.Reader) error { var numIndex int32 if err := binary.Read(r, binary.LittleEndian, &numIndex); err != nil { return err } index := make([]int32, numIndex) s.index = index var last int32 for i := range index { v, err := binary.ReadVarint(r) if err != nil { return err } value := int32(v) + last index[i] = value last = value } return nil } func (s *STRTree) deserializeBBoxes(r *bufio.Reader) error { var numBBoxes int32 if err := binary.Read(r, binary.LittleEndian, &numBBoxes); err != nil { return err } bboxes := make([]Box2D, numBBoxes) s.bboxes = bboxes var err error read := func(v *float64) { if err == nil { err = binary.Read(r, binary.LittleEndian, v) } } for i := range bboxes { read(&bboxes[i].X1) read(&bboxes[i].Y1) read(&bboxes[i].X2) read(&bboxes[i].Y2) } return err } func (s *STRTree) deserialize(r *bufio.Reader) error { s.tin = new(Tin) if err := s.tin.Deserialize(r); err != nil { return err } var numEntries uint8 if err := binary.Read(r, binary.LittleEndian, &numEntries); err != nil { return err } s.Entries = int(numEntries) if err := s.deserializeIndex(r); err != nil { return err } return s.deserializeBBoxes(r) } func (s *STRTree) FromBytes(data []byte) error { r, err := gzip.NewReader(bytes.NewReader(data)) if err != nil { return err } return s.deserialize(bufio.NewReader(r)) } func (t *Tin) Deserialize(r *bufio.Reader) error { if err := binary.Read(r, binary.LittleEndian, &t.EPSG); err != nil { return err } log.Infof("EPSG: %d\n", t.EPSG) if err := t.Min.Read(r); err != nil { return err } if err := t.Max.Read(r); err != nil { return err } log.Infof("BBOX: [[%f, %f, %f], [%f, %f, %f]]\n", t.Min.X, t.Min.Y, t.Min.Z, t.Max.X, t.Max.Y, t.Max.Z) var numVertices uint32 if err := binary.Read(r, binary.LittleEndian, &numVertices); err != nil { return err } log.Infof("vertices: %d\n", numVertices) vertices := make([]Vertex, numVertices) t.Vertices = vertices for i := range vertices { if err := vertices[i].Read(r); err != nil { return err } } var numTriangles uint32 if err := binary.Read(r, binary.LittleEndian, &numTriangles); err != nil { return err } log.Infof("triangles: %d\n", numTriangles) indices := make([]int32, 3*numTriangles) triangles := make([][]int32, numTriangles) t.Triangles = triangles var last int32 for i := range triangles { tri := indices[:3] indices = indices[3:] triangles[i] = tri for j := range tri { v, err := binary.ReadVarint(r) if err != nil { return err } value := int32(v) + last tri[j] = value last = value } } return nil }