% step 1: red layer
% learn about function 'zeros':
help zeros;
% 'zeros' generates a matrix of zeros; arguments to the function denote the
% size of the matrix
% generate a matrix of zeros with 7 rows and 21 columns:
layerRed = zeros(7,21);
% step 2: green layer
layerGreen = zeros(7,21);
% step 3: blue layer
layerBlue = zeros(7,21);

% letter H (red):
layerRed(2:6,2) = 255;
layerRed(2:6,4) = 255;
layerRed(4,3) = 255;

% letter E (green):
layerGreen(2,6:8) = 255;
layerGreen(4,6:8) = 255;
layerGreen(6,6:8) = 255;
layerGreen(3,6) = 255;
layerGreen(5,6) = 255;

% letter L (blue):
layerBlue(2:6,10) = 255;
layerBlue(6,11:12) = 255;

% letter L (yellow = red + green):
% red portion:
layerRed(2:6,14) = 255;
layerRed(6,15:16) = 255;
% green portion:
layerGreen(2:6,14) = 255;
layerGreen(6,15:16) = 255;

% letter O (cyan = green + blue):
% green portion
layerGreen(3:5,18) = 255;
layerGreen(3:5,20) = 255;
layerGreen(2,19) = 255;
layerGreen(6,19) = 255;
% blue portion
layerBlue(3:5,18) = 255;
layerBlue(3:5,20) = 255;
layerBlue(2,19) = 255;
layerBlue(6,19) = 255;

% step 5: generate 3D matrix
hello(:,:,1) = layerRed;
hello(:,:,2) = layerGreen;
hello(:,:,3) = layerBlue;

% step 6: display matrix
hello

% step 7: convert to uint8
helloImage = uint8(hello);

% display image:
image(helloImage);