plotGauge(measureme​nt, rangeGrid, numGrid)

Visualize/plot dial / gauge / meter rendered within MATLAB using OpenGL

function plotGauge(measurement, rangeGrid, numGrid)
% Plot dial / gauge / meter for depicting a measurement
%
% Input Arguments
% 1) measurement - Measurement to be indicated on the meter/gauage/dial
% 2) rangeGrid - Measurement range; default minimum is 0, enter max value
% only
% 3) varargin - (optional) numGrid: Number of equidistant grids to display
%
% Output
% Dial / Gauge / Meter with measurement indicated with an arrow
%
%
% Example:
% m = 150; % measurement entered by user
% rangeGrid = 480; % default min value = 0. Max value is 480
% numGrid = 6; % Ease of readability selected by user
% testplotGauge(m,rangeGrid,numGrid) % Plot the dial with reading
% th = title('Gauge Reading'); % Set title
% set(th,'FontSize',15, 'Position', [0 1.9 0]) % Set title-properties
%
%
% Developed by
% Sowmya Aggarwal
% email: [e-mail]
% M.Sc. Carnegie Mellon University
% M.Sc. University of Pittsburgh
% Error handling for the input arguments
if nargin>1

try
m = measurement;
catch
error('Enter measurement value to be displayed on the dial')
end

if ~isnumeric(m)
error('Enter a valid numeric value to be displayed on the dial')

end

try
maxGrid = rangeGrid; %480;
catch
error('Enter the maximum value allowable for the grid-display')
end

if ~isnumeric(maxGrid) || max(size(maxGrid))>1
error('Enter single numeric value for maximum-allowable value on grid display')
end

% exist(numGrid)

else

error('At least two arguments are required. Type: Help plotGauge for details')
end

%% Set coordinates of dial's graphics
% m = measurement;
% maxGrad = rangeGrid;
rangeTheta = 0:0.1:pi;
rO1 = 1.6; % r = radius, O = outer, 1 = first outer? Outer-most if you will
semicrcO1 = rO1.*[cos(rangeTheta); sin(rangeTheta)]; % Outer-most semicircle coordinates
rO = 1.5; % set dimensions of outer radius
semicrcO = rO.*[cos(rangeTheta); sin(rangeTheta)];
rI = 1.2; % set dimensions of inner radius
semicrcI = rI.*[cos(rangeTheta); sin(rangeTheta)];

%% Plot the Dial
figure1 = figure;
axes1 = axes('Parent',figure1);
hold(axes1,'on');
area(semicrcO1(1,:),semicrcO1(2,:),'Facecolor','w')
hold on
area(semicrcO(1,:), semicrcO(2,:), 'FaceColor','b')
hold on
area(semicrcI(1,:), semicrcI(2,:), 'FaceColor','w')
hold on

%% Plot Meter-Reading Grid Lines on the Dial
hold on
plotPolarGrid(maxGrid,numGrid,rO1,rO,'k')

%% Plot meter-reading / dial-reading / gauge-reading for user-input measurement
maxDeg = pi;
theta = (maxDeg/maxGrid)*m;
xStart = 0; %rI*rangeTheta(length(rangeTheta)/2);
r = (rO+rI)/2;

if m<round(maxGrid/2)
deltaX = xStart-rI*abs(cos(-theta));
end

if m==maxGrid/2
deltaX = xStart;
end

if m>maxGrid/2

deltaX = xStart+rI*abs(cos(theta));
end

yStart = 0; %rI*sin(theta(1));
deltaY = r*abs(sin(theta));

% line([xStart deltaX], [yStart deltaY],...
% 'Color','r',...
% 'LineWidth',4);
hold on
% % Line works but adding an arrow head could be a pain
% line([xstart deltaX], [ystart deltaY],'Color','r')

% % annotation works but setting correct position vector is a pain
% annotation(figure1,'arrow',[0.5 0.7], [0 0.5],...
% 'Color',[0.93 0.7 0.1255],'LineWidth',5,'HeadStyle','plain');
quiver(xStart,yStart,deltaX, deltaY,...
'LineWidth',5,...
'MaxHeadSize',0.3,...
'color',[1 0 0])
scatter(xStart,yStart, 'filled','k' )

axis equal

axis off

hold off

end

function plotPolarGrid(maxGrid, numGrid,radOuter,radMedium,varargin)
%% Plot Grid Lines on the Dial
% disp(varargin)

if nargin>3
color_space = varargin{1,1};
color = char(color_space(1));

end

theta(1:numGrid+1) = fliplr((pi/180)*linspace(0,180,numGrid+1));
n = numGrid+1;

for i=1:n

xStart = radMedium*cos(theta(i));
yStart = radMedium*sin(theta(i));

deltaX = radOuter*cos(theta(i));
deltaY = radOuter*sin(theta(i));

line([xStart,deltaX], [yStart,deltaY], 'Color', char(color) );

if i<n/2
text(1.7*cos(theta(i)),1.7*sin(theta(i)),...
num2str((i-1)*(maxGrid/numGrid)),'HorizontalAlignment','right',...
'FontWeight','bold')
else
text(1.7*cos(theta(i)),1.7*sin(theta(i)),...
num2str((i-1)*(maxGrid/numGrid)),'HorizontalAlignment','left',...
'FontWeight','bold')

end




end

end