Mercurial > gemma

comparison pkg/mesh/areas.go @ 4827:f4abfd0ee8ad remove-octree-debris

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Renamed octree package to mesh as there is no octree any more.
author Sascha L. Teichmann <sascha.teichmann@intevation.de>
date Tue, 05 Nov 2019 14:30:22 +0100
parents pkg/octree/areas.go@a2f16bbcc846
children 181c2c05b12a
comparison
equal deleted inserted replaced
4826:ec5afada70ec 4827:f4abfd0ee8ad
1 // This is Free Software under GNU Affero General Public License v >= 3.0
2 // without warranty, see README.md and license for details.
3 //
4 // SPDX-License-Identifier: AGPL-3.0-or-later
5 // License-Filename: LICENSES/AGPL-3.0.txt
6 //
7 // Copyright (C) 2018 by via donau
8 // – Österreichische Wasserstraßen-Gesellschaft mbH
9 // Software engineering by Intevation GmbH
10 //
11 // Author(s):
12 // * Sascha L. Teichmann <sascha.teichmann@intevation.de>
13
14 package mesh
15
16 import (
17 "runtime"
18 "sync"
19
20 "gemma.intevation.de/gemma/pkg/common"
21 )
22
23 func GenerateRandomVertices(
24 n int,
25 min, max Vertex,
26 eval func(float64, float64) (float64, bool),
27 callback func([]Vertex),
28 ) {
29 var wg sync.WaitGroup
30
31 jobs := make(chan int)
32 out := make(chan []Vertex)
33 done := make(chan struct{})
34
35 cpus := runtime.NumCPU()
36
37 free := make(chan []Vertex, cpus)
38
39 for i := 0; i < cpus; i++ {
40 wg.Add(1)
41 go func() {
42 defer wg.Done()
43 xRange := common.Random(min.X, max.X)
44 yRange := common.Random(min.Y, max.Y)
45
46 for size := range jobs {
47 var vertices []Vertex
48 select {
49 case vertices = <-free:
50 default:
51 vertices = make([]Vertex, 0, 1000)
52 }
53 for len(vertices) < size {
54 x, y := xRange(), yRange()
55 if z, ok := eval(x, y); ok {
56 vertices = append(vertices, Vertex{X: x, Y: y, Z: z})
57 }
58 }
59 out <- vertices
60 }
61 }()
62 }
63
64 go func() {
65 defer close(done)
66 for vertices := range out {
67 callback(vertices)
68 select {
69 case free <- vertices[:0]:
70 default:
71 }
72 }
73 }()
74
75 for remain := n; remain > 0; {
76 if remain > 1000 {
77 jobs <- 1000
78 remain -= 1000
79 } else {
80 jobs <- remain
81 remain = 0
82 }
83 }
84 close(jobs)
85 wg.Wait()
86 close(out)
87 <-done
88 }