From 57c5de06025529db7791b8f193f0bf8901efd1c8 Mon Sep 17 00:00:00 2001
From: "m.uy" <m.uy@ecam.fr>
Date: Fri, 8 Mar 2024 15:18:50 +0100
Subject: [PATCH] first commit

---
 createVisibilityGraph.m | 34 ++++++++++++++++++++++++++++++++++
 ex1.m                   | 15 +++++++++++++++
 2 files changed, 49 insertions(+)
 create mode 100644 createVisibilityGraph.m
 create mode 100644 ex1.m

diff --git a/createVisibilityGraph.m b/createVisibilityGraph.m
new file mode 100644
index 0000000..2d71c50
--- /dev/null
+++ b/createVisibilityGraph.m
@@ -0,0 +1,34 @@
+function [nbNodes, visibilityGraph] = createVisibilityGraph(connectionMatrix, points2D)
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%function [nbNodes, visibilityGraph] = createVisibilityGraph(connectionMatrix, points2D)
+%
+% Task: Create a visibility graph from a connection matrix and a set of 2D points
+%
+% Inputs:
+%	-connectionMatrix: matrix of connection if cell is equal to 1 there is an edge between the corresponding points, cell is 0 otherwise
+%	-points2D: coordinates of the vertices of the graph
+%
+% Outputs:
+%	-nbNodes: the number of nodes of this graph
+%	-visibilityGraph: a matrix containing the distance between connected nodes 
+%		(NaN refers to not connected nodes)
+%		The matrix has a size of (nbNodes+2)x(nbNodes+2)
+%
+% Guillaume Gibert (guillaume.gibert@ecam.fr)
+% 19/03/2021
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+nbNodes = size(points2D,1)-2;
+visibilityGraph = NaN(nbNodes+2, nbNodes+2);
+
+for l_row=1:size(connectionMatrix,1)
+	for l_col=1:size(connectionMatrix,2)
+		if (connectionMatrix(l_row, l_col) == 1)
+			% computes the distance between the 2 points
+			distance = sqrt( (points2D(l_row,1)-points2D(l_col,1))^2 + (points2D(l_row,2)-points2D(l_col,2))^2);
+			visibilityGraph(l_row, l_col) =distance;
+		end
+	end
+end
+
+
diff --git a/ex1.m b/ex1.m
new file mode 100644
index 0000000..8404b07
--- /dev/null
+++ b/ex1.m
@@ -0,0 +1,15 @@
+nbNodes = 8;
+
+visibilityGraph = NaN(nbNodes+2, nbNodes+2);
+visibilityGraph(1,1) =0;visibilityGraph(1,2) =11;visibilityGraph(1,3) =10;
+visibilityGraph(2,1) =11;visibilityGraph(2,3) =18;visibilityGraph(2,9) =11;
+visibilityGraph(3,1) =10;visibilityGraph(3,2) =18;visibilityGraph(3,4) =11;visibilityGraph(3,5) =32;
+visibilityGraph(4,3) =11;visibilityGraph(4,5) =22;visibilityGraph(4,8) =15;visibilityGraph(4,9) =18;
+visibilityGraph(5,3) =32;visibilityGraph(5,4) =22;visibilityGraph(5,6) =11;visibilityGraph(5,8) =20;visibilityGraph(5,9) =37;
+visibilityGraph(6,5) =11;visibilityGraph(6,7) =20;visibilityGraph(6,10) =10;
+visibilityGraph(7,6) =20;visibilityGraph(7,8) =11;visibilityGraph(7,9) =31;visibilityGraph(7,10) =11;
+visibilityGraph(8,4) =15;visibilityGraph(8,5) =20;visibilityGraph(8,7) =11;
+visibilityGraph(9,2) =11;visibilityGraph(9,4) =18;visibilityGraph(9,5) =37;visibilityGraph(9,7) =31;
+visibilityGraph(10,6) =10;visibilityGraph(10,7) =11;
+
+[distanceToNode, parentOfNode] = dijkstra(nbNodes, visibilityGraph);
\ No newline at end of file