function Tromino(action)
%----------------------------------------------------------------------
%INTRODUCTION:
%The inspiration of this game is from Mathematical Problem/Puzzle.
%This Math Problem is very famous and mostly used in Mathematical Induction
%and also in Algorithm Lectures (hence Number Theory).
%I have choosen only 4x4 Chess Board as it is very critical/important step in
%Mathematical Induction.
%Other higher levels of the Puzzle will be repetition of 4x4 levels
%and hence not much of fun.
%The intention of the game is to appreciate the capability of Mathematical
%Induction (not GUI of the game) for problems that look very complicated
%but results in simple solution.
%The solution using Congruence Modulo is, for 2^k x 2^k case (= 4^k), the
%congruence modulo division by 3 (L-Shaped Tromino has 3 unit squares)
%is always 1^k (= 1).
%----------------------------------------------------------------------
global L_Tri L_Tri_count Current_Link;
global CX CY CC fig OriX OriY;
clc;
%--------------------------------------------------------------------------
if nargin < 1,
L_Tri=zeros(4,4);
L_Tri_count=1;
Current_Link=ones(2,2);
Current_Link(1+mod(fix(10*rand(1,1)),2),1+mod(fix(10*rand(1,1)),2))=0;
fig=figure( ...
'Name','Tromino', 'NumberTitle','off', ...
'Visible','off', 'BackingStore','off');
%----------------------------------------------------------------------
% Handling the handles
uicontrol('units','normalized',...
'position',[.8 .61 .07 .05],'string','Help', ...
'callback','Tromino(''Help'')', ...
'interruptible','on','BackgroundColor','w');
uicontrol('units','normalized',...
'position',[.8 .53 .07 .05],'string','Reset', ...
'callback','Tromino(''Reset'')', ...
'interruptible','on','BackgroundColor','w');
uicontrol('units','normalized',...
'position',[.8 .45 .07 .05],'string','Theory', ...
'callback','Tromino(''Theory'')', ...
'interruptible','on','BackgroundColor','w');
uicontrol('units','normalized',...
'position',[.8 .37 .07 .05],'string','Exit', ...
'callback','delete(gcf)', ...
'interruptible','on','BackgroundColor','w');
uicontrol('units','normalized',...
'position',[.49 .18 .06 .05],'string','Fix', ...
'callback','Tromino(''Fix'')', ...
'interruptible','on','BackgroundColor',[1 0.6 0.3]);
uicontrol('units','normalized',...
'position',[.49 .26 .06 .05],'string','Up', ...
'callback','Tromino(''Up'')', ...
'interruptible','on','BackgroundColor',[0 0.6 1]);
uicontrol('units','normalized',...
'position',[.49 .10 .06 .05],'string','Down', ...
'callback','Tromino(''Down'')', ...
'interruptible','on','BackgroundColor',[0 0.6 1]);
uicontrol('units','normalized',...
'position',[.57 .18 .06 .05],'string','Right', ...
'callback','Tromino(''Right'')', ...
'interruptible','on','BackgroundColor',[0 0.6 0.4]);
uicontrol('units','normalized',...
'position',[.41 .18 .06 .05],'string','Left', ...
'callback','Tromino(''Left'')', ...
'interruptible','on','BackgroundColor',[0 0.6 0.4]);
uicontrol('units','normalized',...
'position',[.65 .18 .06 .05],'string','CWR', ...
'callback','Tromino(''CWR'')', ...
'interruptible','on','BackgroundColor',[1 0.4 0.6]);
uicontrol('units','normalized',...
'position',[.33 .18 .06 .05],'string','CCWR', ...
'callback','Tromino(''CCWR'')', ...
'interruptible','on','BackgroundColor',[1 0.4 0.6]);
action='Start';
end
%--------------------------------------------------------------------------
if strcmp(action,'Start')
%4x4 Chess Board
OriX=-1; OriY=-1;
CX=0; CY=4;
CC=[0.9 0.99 0.9;0.99 0.9 0.9;0.9 0.9 0.99;0.7 0.8 0.9;1 1 1];
Update(CX,CY,Current_Link,CC(L_Tri_count,:));
Board();
figure(fig);
end
%--------------------------------------------------------------------------
if strcmp(action,'Help')
msg=strvcat('DESCRIPTION of GAME: ',...
' ',...
'1. Use L-Shaped Trominoes to fill 4x4 Chess Board. ',...
'2. Use directions for [Linear] or (Angular) movements. ',...
'3. Press "Theory" button to know the theory behind this puzzle',...
' (preferrably at the end of the game). ');
msgbox(msg,'Tromino Help','help');
end
%--------------------------------------------------------------------------
if strcmp(action,'Reset')
closereq;
Tromino();
end
%--------------------------------------------------------------------------
if strcmp(action,'Theory')
msg=strvcat('Theory behind the Puzzle: ',...
' ',...
'For any generalized case, say 2^k x 2^k Chess Board, ',...
' using (a) Mathematical Induction or (b) Congruence Modulo',...
' (Number Theory) the puzzle always lead to one unfilled unit square.');
msgbox(msg,'Tromino Theory','help');
end
%--------------------------------------------------------------------------
if strcmp(action,'Exit')
closereq;
end
%--------------------------------------------------------------------------
if strcmp(action,'Up')
CY=CY+1;
Update(CX,CY,Current_Link,CC(L_Tri_count,:));
Board();
end
%--------------------------------------------------------------------------
if strcmp(action,'Down')
CY=CY-1;
Update(CX,CY,Current_Link,CC(L_Tri_count,:));
Board();
end
%--------------------------------------------------------------------------
if strcmp(action,'Right')
CX=CX+1;
Update(CX,CY,Current_Link,CC(L_Tri_count,:));
Board();
end
%--------------------------------------------------------------------------
if strcmp(action,'Left')
CX=CX-1;
Update(CX,CY,Current_Link,CC(L_Tri_count,:));
Board();
end
%--------------------------------------------------------------------------
if strcmp(action,'Fix')
fixit=0;
if (CX-1+OriX>0 && CX-1+OriX<5 && CY+OriY>0 && CY+OriY<5),
if (L_Tri(CX-1+OriX,CY+OriY)==0), fixit=fixit+1; end
end
if (CX+OriX>0 && CX+OriX<5 && CY+OriY>0 && CY+OriY<5),
if (L_Tri(CX+OriX,CY+OriY)==0), fixit=fixit+1; end
end
if (CX-1+OriX>0 && CX-1+OriX<5 && CY-1+OriY>0 && CY-1+OriY<5),
if (L_Tri(CX-1+OriX,CY-1+OriY)==0), fixit=fixit+1; end
end
if (CX+OriX>0 && CX+OriX<5 && CY-1+OriY>0 && CY-1+OriY<5),
if (L_Tri(CX+OriX,CY-1+OriY)==0), fixit=fixit+1; end
end
if fixit>=3,
%fixing the link
L_Tri(CX-1+OriX,CY+OriY) = L_Tri_count*Current_Link(1,1) + L_Tri(CX-1+OriX,CY+OriY);
L_Tri(CX+OriX,CY+OriY) = L_Tri_count*Current_Link(1,2) + L_Tri(CX+OriX,CY+OriY);
L_Tri(CX-1+OriX,CY-1+OriY) = L_Tri_count*Current_Link(2,1) + L_Tri(CX-1+OriX,CY-1+OriY);
L_Tri(CX+OriX,CY-1+OriY) = L_Tri_count*Current_Link(2,2) + L_Tri(CX+OriX,CY-1+OriY);
CX=0; CY=4;
L_Tri_count=L_Tri_count+1;
%checking for the possibilities
valid=Check_L_Tri(L_Tri);
if valid==0 && L_Tri_count>4,
msg='No possibility of Placement of L-Tromino...';
msg_handle=msgbox(msg,'Try Again!','error');
if ~waitforbuttonpress, close(msg_handle); end
Tromino('Prompt');
else
if L_Tri_count>5, Tromino('Prompt');
else
axes('Units','normalized','Visible','off',...
'DrawMode','fast','NextPlot','add');
axes('Units','normalized','Visible','off',...
'DrawMode','fast','NextPlot','replace');
Update(CX,CY,Current_Link,CC(L_Tri_count,:));
Board();
end
end
end
end
%--------------------------------------------------------------------------
if strcmp(action,'CCWR')
Current_Link=rot90(Current_Link);
Update(CX,CY,Current_Link,CC(L_Tri_count,:));
Board();
end
%--------------------------------------------------------------------------
if strcmp(action,'CWR')
Current_Link=rot90(Current_Link,-1);
Update(CX,CY,Current_Link,CC(L_Tri_count,:));
Board();
end
%--------------------------------------------------------------------------
if strcmp(action,'Prompt')
[namastedata namastemap]=imread('namaste.jpg');
msg={'Game is Over...'};
msg_handle=msgbox(msg,'Good Try...!','custom',namastedata,namastemap);
if ~waitforbuttonpress, close(msg_handle); end
PlayAgain='y';
PlayAgain = inputdlg({'Want to Play Again???'},'PlayAgain',1,{PlayAgain});
if strcmp(PlayAgain,'y'),
Tromino('Reset');
else
closereq;
Tromino('Exit');
end
end
%--------------------------------------------------------------------------
