%% patchPathAngles
% Below is a demonstration of the features of the |patchPathAngles| function

%%
clear; close all; clc;

%% Syntax
% |[indAngles]=patchPathAngles(F,V,ind,isClosedLoop);|

%% Description 
% The |patchPathAngles| function computes the angles between adjacent edges
% on a curve on a patch. 

%% Examples 

%% Example 1: Get angles on a closed path defined on the the boundary of a patch
% Create test data set
w=1;
[X,Y]=ndgrid(linspace(0,w,15));
Z=ones(size(X));
C=tril(Z);
[F,V,C]=surf2patch(X,Y,Z,C);
C=vertexToFaceMeasure(F,C)>0;

logicKeep=C>0;
F=F(logicKeep,:);
C=C(logicKeep,:);
[F,V]=patchCleanUnused(F,V);

%%
% Get boundary curve 

Eb=patchBoundary(F);
indBoundaryCurve=edgeListToCurve(Eb);
indBoundaryCurve=indBoundaryCurve(1:end-1)'; %Start=End for closed curve so remove double entry

%%
% Calculate mesh path angles

isClosedPath=1; 
[A]=patchPathAngles(F,V,indBoundaryCurve,isClosedPath);

%%

A=180*(A./pi); % Conver to degrees

% Display unique angles in set
unique(A)

%%

cFigure; hold on;
gpatch(F,V,'kw');
plotV(V(indBoundaryCurve,:),'k-','LineWidth',3);
scatterV(V(indBoundaryCurve,:),75,A,'filled');
colormap gjet; colorbar; caxis([0 360]);
axisGeom; view(2);
drawnow; 

%% Example 2: Study angles for altered shape

V(:,1)=V(:,1)-V(:,2);

%%
% Calculate mesh path angles

isClosedPath=1; 
[A]=patchPathAngles(F,V,indBoundaryCurve,isClosedPath);

%%

A=180*(A./pi); % Conver to degrees

% Display unique angles in set
unique(A)

%%

cFigure; hold on;
gpatch(F,V,'kw');
plotV(V(indBoundaryCurve,:),'k-','LineWidth',3);
scatterV(V(indBoundaryCurve,:),75,A,'filled');
colormap gjet; colorbar; caxis([0 360]);
axisGeom; view(2);
drawnow; 

%% Example 3: Get angles on a non-closed path defined on the the boundary of a patch

%%
% Create path segment
indBoundaryCurve=indBoundaryCurve(1:6);

%%
% Calculate mesh path angles
isClosedPath=0; 
[A]=patchPathAngles(F,V,indBoundaryCurve,isClosedPath);

%%

A=180*(A./pi); % Conver to degrees

% Display unique angles in set
unique(A(~isnan(A)))

%%

cFigure; hold on;
gpatch(F,V,'kw');
plotV(V(indBoundaryCurve,:),'k-','LineWidth',3);
scatterV(V(indBoundaryCurve,:),75,A,'filled');
colormap gjet; colorbar; caxis([0 360]);
axisGeom; view(2);
drawnow; 

%% 
%
% <<gibbVerySmall.gif>>
% 
% _*GIBBON*_ 
% <www.gibboncode.org>
% 
% _Kevin Mattheus Moerman_, <gibbon.toolbox@gmail.com>
 
%% 
% _*GIBBON footer text*_ 
% 
% License: <https://github.com/gibbonCode/GIBBON/blob/master/LICENSE>
% 
% GIBBON: The Geometry and Image-based Bioengineering add-On. A toolbox for
% image segmentation, image-based modeling, meshing, and finite element
% analysis.
% 
% Copyright (C) 2006-2022 Kevin Mattheus Moerman and the GIBBON contributors
% 
% This program is free software: you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation, either version 3 of the License, or
% (at your option) any later version.
% 
% This program is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
% GNU General Public License for more details.
% 
% You should have received a copy of the GNU General Public License
% along with this program.  If not, see <http://www.gnu.org/licenses/>.
