function colorwheel = colorwheel(colorlevel,saturation,luminance)
if ~exist('saturation','var'), saturation = []; end
if ~exist('luminance','var'), luminance = []; end
if isempty(saturation), saturation = 1; end
if isempty(luminance), luminance = 1; end
x = linspace(-pi,pi,colorlevel);
x = x(1:end-1)';
colorwheel = ([cos(x),cos(x-pi/3*2),cos(x-pi/3*4)]+1).*saturation/2+1-saturation;
colorwheel = colorwheel.*luminance;
end