%% PLAY & SHOW
width=100;
dot_rate=0.5;
board=round(dot_rate*rand(width+2,width+2));
t=1;
times=1000;
while t<=times
    board=generate_step(board);
    imshow(zoom_out(board));
    t=t+1;
end

%% RULES
function state=life_rules(fore_state,neighbor_state)
state((fore_state==1&&(neighbor_state==2||neighbor_state==3))||(fore_state==0&&neighbor_state==3))=1;
state((fore_state==1&&(neighbor_state<=1||neighbor_state>=4))||(fore_state==0&&neighbor_state~=3))=0;
end

function board=generate_step(fore_board)
expand_width=size(fore_board,1);

board(1,1)=fore_board(expand_width-1,expand_width-1);% Cross assignment of four boundary points
board(expand_width,expand_width)=fore_board(2,2);
board(1,expand_width)=fore_board(expand_width-1,2);
board(expand_width,1)=fore_board(2,expand_width-1);

board(1,2:expand_width-1)=fore_board(expand_width-1,2:expand_width-1);% Cross assignment of four boundary bars
board(expand_width,2:expand_width-1)=fore_board(2,2:expand_width-1);
board(2:expand_width-1,1)=fore_board(2:expand_width-1,expand_width-1);
board(2:expand_width-1,expand_width)=fore_board(2:expand_width-1,2);

for i=2:expand_width-1
    for j=2:expand_width-1
        neighbor_state=sum(sum(fore_board(i-1:i+1,j-1:j+1)))-fore_board(i,j);
        board(i,j)=life_rules(fore_board(i,j),neighbor_state);
    end
end
end

function expand_board=zoom_out(board)
width=size(board,1);
expand_rate=7;% 7×7 pixels displayed as a cell.
expand_board=zeros(expand_rate*width);
for i=1:width
    for j=1:width
        expand_board(expand_rate*(i-1)+1:expand_rate*i,expand_rate*(j-1)+1:expand_rate*j)=board(i,j);
    end
end
end