annotate pkg/wkb/wkb.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>
date Thu, 21 Oct 2021 19:50:39 +0200
parents 95786a675d70
children
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1 // This is Free Software under GNU Affero General Public License v >= 3.0
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2 // without warranty, see README.md and license for details.
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3 //
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4 // SPDX-License-Identifier: AGPL-3.0-or-later
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5 // License-Filename: LICENSES/AGPL-3.0.txt
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6 //
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7 // Copyright (C) 2018 by via donau
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8 // – Österreichische Wasserstraßen-Gesellschaft mbH
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9 // Software engineering by Intevation GmbH
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10 //
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11 // Author(s):
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12 // * Sascha L. Teichmann <sascha.teichmann@intevation.de>
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13
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14 package wkb
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15
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16 // Binary encoding in WKB data.
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17 const (
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18 XDR byte = 0 // big endian.
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19 NDR byte = 1 // little endian.
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20 )
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21
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22 // Various types of geometry.
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23 const (
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24 Point uint32 = 1
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25 LineString uint32 = 2
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26 Polygon uint32 = 3
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27 MultiLineString uint32 = 5
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28 MultiPolygon uint32 = 6
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29 PointZ uint32 = 1000 + 1
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30 LineStringZ uint32 = 1000 + 2
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31 MultiPointZ uint32 = 1000 + 4
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32 MultiLineStringZ uint32 = 1000 + 5
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33 TinZ uint32 = 1000 + 16
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34 TriangleZ uint32 = 1000 + 17
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35 )