1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
## Copyright (C) 2024 David Legland
## All rights reserved.
##
## Redistribution and use in source and binary forms, with or without
## modification, are permitted provided that the following conditions are met:
##
## 1 Redistributions of source code must retain the above copyright notice,
## this list of conditions and the following disclaimer.
## 2 Redistributions in binary form must reproduce the above copyright
## notice, this list of conditions and the following disclaimer in the
## documentation and/or other materials provided with the distribution.
##
## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ''AS IS''
## AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
## IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
## ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
## ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
## DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
## SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
## CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
## OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
##
## The views and conclusions contained in the software and documentation are
## those of the authors and should not be interpreted as representing official
## policies, either expressed or implied, of the copyright holders.
function [minDist, pos] = distancePointPolyline(point, poly, varargin)
%DISTANCEPOINTPOLYLINE Compute shortest distance between a point and a polyline.
%
% DIST = distancePointPolyline(POINT, POLYLINE)
% Returns the shortest distance between a point given as a 1-by-2 row
% vector, and a polyline given as a NV-by-2 array of coordinates.
%
% If POINT is a NP-by-2 array, the result DIST is a NP-by-1 array,
% containig the distance of each point to the polyline.
%
% [DIST, POS] = distancePointPolyline(POINT, POLYLINE)
% Also returns the relative position of the point projected on the
% polyline, between 0 and NV, the number of polyline vertices.
%
% ... = distancePointPolyline(POINT, POLYLINE, CLOSED)
% Specifies if the polyline is closed or not. CLOSED can be one of:
% * 'closed' -> the polyline is closed
% * 'open' -> the polyline is open
% a column vector of logical with the same number of elements as the
% number of points -> specify individually if each polyline is
% closed (true=closed).
%
%
% Example:
% pt1 = [30 20];
% pt2 = [30 5];
% poly = [10 10;50 10;50 50;10 50];
% distancePointPolyline([pt1;pt2], poly)
% ans =
% 10
% 5
%
% See also
% polygons2d, points2d
% distancePointEdge, distancePointPolygon, projPointOnPolyline
%
% ------
% Author: David Legland, Juan Pablo Carbajal
% E-mail: david.legland@inrae.fr, ajuanpi+dev@gmail.com
% Created: 2009-04-30, using Matlab 7.7.0.471 (R2008b)
% Copyright 2009-2023 INRA - Cepia Software Platform
% check if input polyline is closed or not
closed = false;
if ~isempty(varargin)
c = varargin{1};
if strcmp('closed', c)
closed = true;
elseif strcmp('open', c)
closed = false;
elseif islogical(c)
closed = c;
end
end
% closes the polyline if necessary
if closed
poly = [poly; poly(1,:)];
end
% number of points
Np = size(point, 1);
% construct the set of edges
edges = [poly(1:end-1, :) poly(2:end, :)];
% compute distance between current each point and all edges, and also
% returns the position of projection on corresponding edge, between 0 and 1
[dist, edgePos] = distancePointEdge(point, edges);
% get the minimum distance, and index of edge providing minimum distance
[minDist, edgeIndex] = min(dist, [], 2);
% if required, compute projections
pos = [];
if nargout == 2
Ne = size(edgePos, 2);
j = sub2ind([Np, Ne], (1:Np)', edgeIndex);
pos = edgeIndex - 1 + edgePos(j);
end
|
