area_finder.m

function [Ax,Ay,Az] = area_finder(xyz,conn);
% This function estimates normalised 
% net cross-section areas of the RCM 
% relatively to the x,y,z axes. 
% Only the path with weight 1 is considered 
% for estimating the area to avoid ambiguity
% in defining the edge of the area. 

idx = find(conn(:,1) ~= 1);
conn(idx,:) = [];

X = xyz(conn(:,2),1);
Y = xyz(conn(:,2),2);
Z = xyz(conn(:,2),3);

Ax = polyarea(Y,Z);
Ay = polyarea(X,Z);
Az = polyarea(X,Y);

scale_factor = sqrt(Ax^2+Ay^2+Az^2);

Ax = Ax/scale_factor;
Ay = Ay/scale_factor;
Az = Az/scale_factor;


if 1
if ~ispolycw(Z,Y)
    Ax = -1*Ax;
end

if ~ispolycw(X,Z)
    Ay = -1*Ay;
end

if ~ispolycw(Y,X)
    Az = -1*Az;
end
end











end