Here is ax example
t = linspace(0,2*pi,4); % triangle
[x,y] = pol2cart(t,30); % cartesian coordinates
% move triangle to (50,50)
x = x + 50;
y = y + 50;
[x1,y1] = meshgrid(1:100);
A = zeros(100); % preallocation memory
ind = inpolygon(x1,y1,x,y); % indices inside the triangle
A(ind) = 1;
imshow(A)
