ECE5725
RPi Based AR Game


By Yexiang Chang (yc2523) & Mengde Wu (mw934)
December 2018


Demonstration Video


Introduction

We developed an AR game based on RPi in our project. In this game, player can control a robot through WiFi to explore the environment around it. There would be some monsters and other items for player to find. Player can fight with monsters to gain experience or can be defeated by a monster. Enough experience can level up player and monsters can grow stronger, too.


Generic placeholder image

Project Objective:

  • Designed the whole game, mainly about exploring and battle
  • Display game interface on real scene to achieve effects
  • Read input from keyboard to RPi through WiFi
  • Transfer images from RPi to monitor through WiFi
  • Enhance the visual effects of game

Design

PyGame

In our game the background should be the real environment picture, so we need use camera to take video. First we installed PiCamera on RPi as our camera. Then we can put game interface upon the video to augment reality, so players can play with real scene as background.

Initially, we used code provided by PiCamera documentation[1] to get video from PiCamera, and the way this code did it is it asks camera to take photos every certain seconds and store it as a jpg file. To make it a video, we use PyGame to load this jpg file every certain seconds so people can see a video. But this method is slow and the frames per second is too low to allow players react to attacks from monsters.

In order to improve the frames per second, we tried use NumPy to store the images from camera and transfer them to PyGame for further operation so we don’t need to store a jpg file in disk which is time expensive. NumPy makes the video much smoother, but still not good enough. Finally, we installed openCV on our Pi and use libraries provided by openCV to read NumPy arrays from PiCamera, and it works very well as monsters can show on the screen in a very smooth way.

Generic placeholder image

In the figure above, the background is video catched by PiCamera, and upon that there is a small blue monster bouncing around to helps us test if the frames per second is good enough.

Communication Between RPi and Host

Players will control robot to explore the surrounding environment instead of hold a RPi and hang around, so we don’t want to display our game on PiTFT or use buttons on it. A wireless controller (host) is necessary. In our project, we use a laptop as the host.

At first we tried use a laptop to control RPi through WiFi and VNCserver. In order to use VNC we installed tightvncserver on RPi. Through VNC Viewer installed on a device, we can connect to RPi through WiFi and start the game. It works on a laptop or an iPad. But here is the problem again, the frames per second is too slow to allow players play this game normally. We thought if we could improve the internet speed the display can be better, and then we tried using laptop itself as a WiFi hotspot and let RPi connect to it directly. Hotspot makes video smoother but still not good enough.

Actually, we tried using ssh to connect laptop and RPi at the very first time, but we found that we can’t run PyGame through ssh so we turned to other solution. But after all those attempts failed to meet our expectation, we finally found X11 forwarding which allows ssh to run PyGame.

X11 forwarding is a special case of remote tunneling and we can easily display the window of pygame on our laptop with X11 forwarding. Since X11 server has already installed on Mobaxterm, we don’t need to install other tools on our laptop. But there are other things that need to be set on our RPi.

We need to run our main.py code with sudo to start the game because we need to run openCV in our program, but it has something conflicting with X11 forwarding. The normal X-forwarding can only work without sudo. So at first we couldn’t run our game with sudo, but we finally solved this problem with a tutorial[2].

Following the tutorial, we first use our Mobaxterm with ssh:

ssh pi@(our ip)

Then we need to enter a command:

xauth list $DISPLAY

This command will returns:

server/unix:10 MIT-MAGIC-COOKIE-1 blablablablabla

Note that this will change every time we connect our RPi with ssh, so we have do these things every time. Then we need to change a file as root:

sudo su

xauth add server/unix:10 MIT-MAGIC-COOKIE-1 blablablablabla

After doing this, we actually have already set up the X11 server successfully. You can check if you have done with command:

xauth list

At last, we can change the user to pi and run your PyGame code with sudo. Solving this makes our pygame window run successfully on our laptop

Robot

As it is mentioned before, players will control a robot to play this game. The skeleton of robot is shown in the figure below.

Generic placeholder image

On this skeleton we installed 2 wheels and 2 servos to control wheels, a battery pack to provide energy for servos as our basic robot.

Generic placeholder image

We used Parallax Continuous Rotation Servo in our project. To control the servo, we basically will need to use RPi to generate PWM signals and send them to servos. The connection of RPi servos is shown in the figure below.

Generic placeholder image

The signal shown in the figure below will stop the servo, and if we change the pulse width to 1.3ms, the servo will rotate in clockwise at its fastest speed, or if we change the pulse width to 1.7ms, the servo will rotate in counterclockwise at its fastest speed.

Generic placeholder image

The figure shown below is the robot we finally have. Beside wheels and servos, we installed RPi, a breadboard, PiCamera, a mobile charger to support RPi and a speaker above to play music.

Generic placeholder image

Game

Basically the game consists of two parts: exploring and battle.

Generic placeholder image

In the exploring part, players will control the robot to explore the surrounding environment. Like shown in the figure below, player can either use keyboard or click arrows on the screen to move the robot. The status including health points, mage points, experience, count of death and attack power of player is shown on the left side and a small map is shown on the right side, the red spots on the map means there is a monster in that block.

The map is a 5 x 5 grid, which we use a 5 x 5 matrix in NumPy to implement it. We initialize this matrix by filling it with random numbers range from 1 to 20. When a element in this matrix is between 2-6, in the block this element represent would be a monster, and the kind of monster is correspond to the number, for instance, if the element is 6, there should be a dragon in this block.

Generic placeholder image

And when the player is moving in this map, the arrow which represent the location player at now will stay in the center of this map, while the map will move relatively. During moving, the farest column or row in the direction of moving will generate a set of new elements. The way we generate new elements is we generate 2 numbers, one of them ranges from 1-9 and another ranges from 1-5. The first number indicates what will be in a block, and the second indicates which block this thing will be in among the 5 blocks of the new column/row. And when the number is 7 or 8 there would be a sword or a fountain respectfully. Sword can increase the attack of player and fountain can recover player from wounds, and both of them will be marked as blue spots on the map. This mechanism of generating new columns/rows of map can reduce the space to store a large map and increase the speed of reading a map. What’s more, it allows players explore the environment without space constraints.

Generic placeholder image

When the player is close to a monster and face to them, monsters will show in the player’s vision like the figure shown below.

Generic placeholder image

If the monster is at the middle, that means this monster is in the block in front of you, and if the monster is at the left/right side, that means this monster is in the block in forward left/forward right.

When the player walk in a block with monster, then the game would change to battle phase. In the battle phase, the monster will look larger and will jump in the screen. Monsters will attack players automatically, and player will lose certain health points according to the monsters’ attack. Player can either use normal attack or skill to attack monsters. Push number “1” can use normal attack, push “2” can use skill which has more damage than normal attack but will cost mage points, and push “3” can use heal skill which can heal player but cost some mage points.

Generic placeholder image

If player kill a monster, it will give you experience as award and the amount of experience depends on how strong the monster is, a stronger monster usually will award player more experience. And when a monster is killed, the next monster of the same kind will have a higher level and is stronger than before. When the experience bar is full, player will level up and attack power of player will increase. If player is killed, the death counts will plus one, and player respawn in the block he/she is.

When playing this game, the speaker will play different background music under different conditions, and when you fight with monsters, there would be both sound effects and visual effects.


Results

We successfully designed a game on RPi and display the interface of game upon a real scene catched by PiCamera. Realized wireless control and display with a laptop through WiFi and enable player to control the robot to explore. In general, the game fully meet our expectation. Besides, we also developed some interesting additional stuffs like sword and fountain, and greatly enhanced the interface of our game which make this game more fun!

Generic placeholder image

Conclusion

In this project, we not only develop a game but also learned a lot from the process of developing it. And of course, we came across many problems while doing it.

In the beginning, we used a function named getch in a while loop to get input from keyboard, which means this program will keep polling input from keyboard. And this cause us have to use two Python programs, one to run getch in the background and one to run the game. Besides, in order to exchange information between these two Python programs, we need another txt file to store the temporary information including map matrix and input from keyboards and others. We tried using FIFO to solve this problem at first, but we want to read information from another file multiple times but only write once, so it is hard to implement it with FIFO. Because we will control RPi wirelessly, the wait-for-edge in GPIO doesn’t work either, and we struggling with two Python programs for a long time. In the last week, we find a simple way to solve this problem which is use event in PyGame to read input from keyboards, there are certain event type of mouse and keyboard, and because PyGame is the core part of our code, so it can perfectly fit in our main program. By using this method, we combined those two programs as one.

Like we can’t use polling to get input, we can’t use time.sleep() to keep program running since it will block other codes from running. And the solution to that is using time.time() to get the start time and keep using time.time() to subtract the start time so to check the time.

Communication between RPi and laptop is complex when we need to transfer video. In the process of developing this part, we tried VNC server and VNC server with hotspot, but both of them didn’t meet our expectation because they are too slow. We finally used X11 forwarding. It works much smoother than before but it is only acceptable because the protocol it used is designed in 70s and out of time, it could be faster to transfer video through WiFi, but we didn’t find a better solution than X11 forwarding.

Working under openCV environment is annoying sometimes, because we have to enter a bunch of commands in order to work on openCV, and it can’t be input in a bash script, we didn’t find much about how to make openCV start automatically.

At the end of this project, we made an animation on the title and ending window, which is all of our monsters jump in the screen and jump out gradually. It is more complex than we expect, basically we made a matrix to store speed of each monster, the horizontal speed for every monster is a constant and they are equal, while the vertical speed will suddenly increase a random number when the monster contact with the bottom of screen, and it will gradually decrease when the monster is jumping up. All this setting made monsters jump like there is gravity, and it looks fun!

Generic placeholder image

Future Works

1. Improve the quality of video tranfer
2. Improve the visual effects
3. Add more monsters and skills
4. Make battle mechanism more various
5. Make a storyline for this game


Work Distribution

Generic placeholder image

Project group picture

Generic placeholder image

Mengde Wu

mw934@cornell.edu

Developed the game exploring interface, servo
programs and communication system

Generic placeholder image

Yexiang Chang

yc2523@cornell.edu

Developed the game battle interface, PiCamera
and openCV programs and communication system


Parts List

Total: $0 (We didn't buy anything! XD)


References

PiCamera Document
Parallax Continuous Rotation Servo Datasheet
X11 Forwarding
PyGame
OpenCV Library

Code Appendix

header.py

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
#!/usr/bin/env python
# Team member: name: Mengde Wu netId: mw934
#              name: Yexiang Chang netId: yc2523
import numpy as np
from random import uniform
import pygame
from pygame.locals import *
import sys, termios, tty, os
import time
import RPi.GPIO as GPIO
import cv2
import subprocess


# setup the callback routine, the system will run the callback function
# if it detects a falling edge in one of these GPIOs
GPIO.setmode(GPIO.BCM) 
GPIO.setup(26, GPIO.OUT)
GPIO.setup(5, GPIO.OUT)

s1 = GPIO.PWM(26, 46.5)
s2 = GPIO.PWM(5, 46.5)
s1.start(0)
s2.start(0)


# num:1 left servo
#     2 right servo

# dir:1 clockwise
#     -1 counterclockwise
#     0 stop
def set_direction(num,dir):
    if num==1:
        if dir==1:
            dc=7.8
        elif dir==0:
            dc=0
        elif dir==-1:
            dc=6.0
        s1.ChangeDutyCycle(dc)
    elif num==2:
        if dir==1:
            dc=7.8
        elif dir==0:
            dc=0
        elif dir==-1:
            dc=6.0
        s2.ChangeDutyCycle(dc)

class Monster:
    def __init__(self,Skill,mid,pic,lv,name,hp,atk,defen,money,exp):
        self.Skill=Skill
        self.mid = mid
        self.pic = pic
        self.lv = lv
        self.name = name
        self.hp = hp
        self.atk = atk
        self.defen = defen
        self.money = money
        self.exp = exp
    
class Skill:
    def __init__(self,name,dmg,pic,cost):
        self.name = name
        self.dmg = dmg
        self.pic = pic
        self.cost = cost   
        
class Player:
    def __init__(self,Skill,hp,mp,lv,exp,atk,death):
        self.Skill = Skill
        self.hp = hp
        self.mp = mp
        self.lv = lv
        self.exp = exp
        self.atk = atk
        self.death = death

def map_generator():

    map = np.zeros(49).reshape(7,7)

    for i in range(5):
        for j in range(5):
            map[i+1,j+1] = int(uniform(1.0,21.0))
            if map[i+1,j+1] >= 7:
                map[i+1,j+1] = 1
                
    map[3,3] = 1
    return map

def check_facing(pos,map):
    if pos[2] == 1:
        facing = np.array([int(map[pos[0]-1,pos[1]+1]),\
                           int(map[pos[0],pos[1]+1]),\
                           int(map[pos[0]+1,pos[1]+1])])
    elif pos[2] == 2:
        facing = np.array([int(map[pos[0]-1,pos[1]-1]),\
                           int(map[pos[0]-1,pos[1]]),\
                           int(map[pos[0]-1,pos[1]+1])])
    elif pos[2] == 3:
        facing = np.array([int(map[pos[0]+1,pos[1]-1]),\
                           int(map[pos[0],pos[1]-1]),\
                           int(map[pos[0]-1,pos[1]-1])])
    elif pos[2] == 4:
        facing = np.array([int(map[pos[0]+1,pos[1]+1]),\
                           int(map[pos[0]+1,pos[1]]),\
                           int(map[pos[0]+1,pos[1]-1])])
    
    return facing

# check if all the monsters in the map are killed
def check_map(map):
    if np.max(map) == 1:
	return 1
    return 0

# initialize monsters
rush = Skill(name='rush',dmg=1,pic='',cost=1)
bat = Monster(rush,mid=1,pic='bat.png',lv=1,name='Bat',\
                 hp=4,atk=1,defen=1,money=1,exp=5)
centaur = Monster(rush,mid=2,pic='centaur.png',lv=1,name='Centaur',\
                 hp=8,atk=5,defen=5,money=10,exp=10)
angryboy = Monster(rush,mid=3,pic='angryboy.png',lv=1,name='Angryboy',\
                 hp=16,atk=10,defen=8,money=100,exp=15)
pumpkin = Monster(rush,mid=4,pic='pumpkin.png',lv=1,name='Pumpkin',\
                 hp=32,atk=15,defen=15,money=500,exp=30)
dragon = Monster(rush,mid=5,pic='dragon.png',lv=1,name='Dragon',\
                 hp=64,atk=20,defen=30,money=1000,exp=50)

# initialize player
player = Player(rush,hp=100,mp=100,lv=1,exp=0,atk=8,death=0)

main.py

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
#!/usr/bin/env python
# Team member: name: Mengde Wu netId: mw934
#              name: Yexiang Chang netId: yc2523

import sys
import pygame
from pygame.locals import *
import time
import cv2
import os
import numpy as np
from header import *

######################################## Initialization #########################################

# initialize pygame
pygame.init()
pygame.display.set_caption('PI AR GAME')

# set color
black = 0, 0, 0
green = 124, 252, 0
red = 255, 0, 0
blue = 0, 255, 255
yellow = 255, 215, 0
white = 255, 255, 255

# set the size of screen to 640*480
size = width, height = 640, 480
# initialize the screen with parameter size
screen = pygame.display.set_mode(size)

# load all images
map_image = pygame.transform.scale(pygame.image.load("map.jpg")\
                                        ,(120,120))
map_rect = map_image.get_rect(center=[width-80,80])

pi_image = pygame.transform.scale(pygame.image.load("pi.png")\
                                        ,(90,120))
pi_rect = pi_image.get_rect(center=[150,240])

ar_image = pygame.transform.scale(pygame.image.load("ar.png")\
                                        ,(90,120))
ar_rect = ar_image.get_rect(center=[260,240])

game_image = pygame.transform.scale(pygame.image.load("game.png")\
                                        ,(250,120))
game_rect = game_image.get_rect(center=[450,240])

hero_image = pygame.transform.scale(pygame.image.load("hero.png")\
					,(100,100))
hero_rect = hero_image.get_rect(center=[70,70])


sword_image = pygame.transform.scale(pygame.image.load("sword.png")\
					,(128,128))
spring_image = pygame.transform.scale(pygame.image.load("spring.png")\
					,(128,118))

atk_image = pygame.transform.scale(pygame.image.load('attack.png')\
                                        ,(100,100))

skill_image = pygame.transform.scale(pygame.image.load('skill.png')\
                                        ,(200,200))
skill_rect = skill_image.get_rect(center=[320,240])

dead_image = pygame.transform.scale(pygame.image.load('dead.png')\
                                        ,(300,300))
dead_rect = dead_image.get_rect(center=[320,240])

heal_image = pygame.transform.scale(pygame.image.load('heal.png')\
                                        ,(100,100))

skillbutton_image = pygame.transform.scale(pygame.image.load('skillbutton.png')\
                                        ,(100,30))

forward_image = pygame.transform.scale(pygame.image.load('forward.png')\
                                        ,(100,100))
forward_rect = forward_image.get_rect(center=[320,80])

backward_rect = forward_image.get_rect(center=[320,480-80])

left_image = pygame.transform.scale(pygame.image.load('right.png')\
                                        ,(100,100))

left_rect = left_image.get_rect(center=[70,480-70])

right_rect = left_image.get_rect(center=[640-70,480-70])

close_image = pygame.transform.scale(pygame.image.load('close.png')\
                                        ,(20,20))
close_rect = close_image.get_rect(center=[640-10,10])

# set font
my_font = pygame.font.Font(None, 20)

# initialize camera (using opencv, videocapture)
camera = cv2.VideoCapture(0)

############################# Drawing(virtual buttons; UI; Background) #####################################

display_mode = True

# draw the virtual buttons
def draw_movebutton():
    screen.blit(forward_image,forward_rect)
    screen.blit(pygame.transform.flip(forward_image, False, True),backward_rect)
    screen.blit(left_image,left_rect)
    screen.blit(pygame.transform.flip(left_image, True, False),right_rect)
  
# draw the ui of this game
def draw_ui():
    global pos, map_image,map_rect
    global map
    global name
    
    # show player lv and name
    screen.blit(map_image, map_rect)
    screen.blit(hero_image, hero_rect)
    
    ply_info = 'lv: '+str(player.lv)+'  '+name
    ply_button = {ply_info:(55,125),\
                  'HP: ':(35,145),\
                  'MP: ':(35,165),\
                  'EXP:':(35,185),\
                  'Death: '+str(player.death):(45,205),\
		          'Atk: '+str(player.atk):(40,225)}
    
    # show player hp
    pygame.draw.rect(screen,red,(20,\
                                 140,\
                                 100,
                                 10),0)
    pygame.draw.rect(screen,green,(20,\
                                 140,\
                                 player.hp,
                                 10),0)
    
    # show player mp
    pygame.draw.rect(screen,red,(20,\
                                 160,\
                                 100,
                                 10),0)
    pygame.draw.rect(screen,blue,(20,\
                                 160,\
                                 player.mp,
                                 10),0)
    
    # show player exp
    pygame.draw.rect(screen,red,(20,\
                                 180,\
                                 100,
                                 10),0)
    pygame.draw.rect(screen,yellow,(20,\
                                 180,\
                                 player.exp,
                                 10),0)
    
    for my_text, text_pos in ply_button.items():
        text_surface = my_font.render(my_text, True, white)
        rect = text_surface.get_rect(center=text_pos)
        screen.blit(text_surface, rect)
    
    if display_mode:
    	for i in range(5):
	    for j in range(5):
	    	if map[i+1,j+1] > 1 and map[i+1,j+1] <= 6:
                    pygame.draw.circle(screen, red, [560+(j+0-3)*24+24,\
                                                 80+(i+2-3)*24-24], 5)
	    	if map[i+1,j+1] == 7:
                    pygame.draw.circle(screen, blue, [560+(j+0-3)*24+24,\
                                                 80+(i+2-3)*24-24], 5)
	    	if map[i+1,j+1] == 8:
                    pygame.draw.circle(screen, green, [560+(j+0-3)*24+24,\
                                                 80+(i+2-3)*24-24], 5)			
    
    
    	arrow_image = pygame.transform.scale(pygame.image.load("arrow.png")\
                                        ,(20,20))
    	arrow_rotate = pygame.transform.rotate(arrow_image, 90*(pos[2]-1))
    	arrow_rect = arrow_rotate.get_rect(center=[560+(pos[1]-3)*24,80+(pos[0]-3)*24])
    	screen.blit(arrow_rotate, arrow_rect)

    else:
	
        arrow_image = pygame.transform.scale(pygame.image.load("arrow.png")\
                                        ,(20,20))
    	arrow_rotate = pygame.transform.rotate(arrow_image, 90*(2-1))
    	arrow_rect = arrow_rotate.get_rect(center=[560,80])

	    if pos[2] == 2:
    	    for i in range(5):
	    	for j in range(5):
	    	    if map[i+1,j+1] > 1 and map[i+1,j+1] <= 6:
                    	pygame.draw.circle(screen, red, [560+(j+0-3)*24+24,\
                                                 80+(i+2-3)*24-24], 5)
	    	    if map[i+1,j+1] == 7:
                    	pygame.draw.circle(screen, blue, [560+(j+0-3)*24+24,\
                                                 80+(i+2-3)*24-24], 5)
	    	    if map[i+1,j+1] == 8:
                    	pygame.draw.circle(screen, green, [560+(j+0-3)*24+24,\
                                                 80+(i+2-3)*24-24], 5)
	    elif pos[2] == 4:
    	    for i in range(5):
	    	for j in range(5):
	    	    if map[i+1,j+1] > 1 and map[i+1,j+1] <= 6:
                    	pygame.draw.circle(screen, red, [560+(4-j+0-3)*24+24,\
                                                 80+(4-i+2-3)*24-24], 5)
	    	    if map[i+1,j+1] == 7:
                    	pygame.draw.circle(screen, blue, [560+(4-j+0-3)*24+24,\
                                                 80+(4-i+2-3)*24-24], 5)
	    	    if map[i+1,j+1] == 8:
                    	pygame.draw.circle(screen, green, [560+(4-j+0-3)*24+24,\
                                                 80+(4-i+2-3)*24-24], 5)
	    elif pos[2] == 1:
    	    for i in range(5):
	    	for j in range(5):
	    	    if map[i+1,j+1] > 1 and map[i+1,j+1] <= 6:
                    	pygame.draw.circle(screen, red, [560+(i+0-3)*24+24,\
                                                 80+(4-j+2-3)*24-24], 5)
	    	    if map[i+1,j+1] == 7:
                    	pygame.draw.circle(screen, blue, [560+(i+0-3)*24+24,\
                                                 80+(4-j+2-3)*24-24], 5)
	    	    if map[i+1,j+1] == 8:
                    	pygame.draw.circle(screen, green, [560+(i+0-3)*24+24,\
                                                 80+(4-j+2-3)*24-24], 5)
	    elif pos[2] == 3:
    	    for i in range(5):
	    	for j in range(5):
	    	    if map[i+1,j+1] > 1 and map[i+1,j+1] <= 6:
                    	pygame.draw.circle(screen, red, [560+(4-i+0-3)*24+24,\
                                                 80+(j+2-3)*24-24], 5)
	    	    if map[i+1,j+1] == 7:
                    	pygame.draw.circle(screen, blue, [560+(4-i+0-3)*24+24,\
                                                 80+(j+2-3)*24-24], 5)
	    	    if map[i+1,j+1] == 8:
                    	pygame.draw.circle(screen, green, [560+(4-i+0-3)*24+24,\
                                                 80+(j+2-3)*24-24], 5)
	
    	screen.blit(arrow_rotate, arrow_rect)
    
    screen.blit(close_image,close_rect)

# draw the background of the game
def background():
    global screen,camera
    
    ret, frame = camera.read()
    frame = cv2.cvtColor(frame,cv2.COLOR_BGR2RGB)
    frame = np.rot90(frame)
    frame = np.fliplr(frame)
    frame = pygame.surfarray.make_surface(frame)
    
    # show background
    screen.blit(frame,(0,0))
    
    draw_ui()

# draw the monster (show what you are facing)    
def generate_monster(num,Center):
    if num == 2:
        monster = pygame.image.load(bat.pic)
        mon_rect = monster.get_rect(center=Center)
        screen.blit(monster,mon_rect)
    elif num == 3:
        monster = pygame.image.load(centaur.pic)
        mon_rect = monster.get_rect(center=Center)
        screen.blit(monster,mon_rect)
    elif num == 4:
        monster = pygame.image.load(angryboy.pic)
        mon_rect = monster.get_rect(center=Center)
        screen.blit(monster,mon_rect)
    elif num == 5:
        monster = pygame.image.load(pumpkin.pic)
        mon_rect = monster.get_rect(center=Center)
        screen.blit(monster,mon_rect)
    elif num == 6:
        monster = pygame.image.load(dragon.pic)
        mon_rect = monster.get_rect(center=Center)
        screen.blit(monster,mon_rect)
    elif num == 7:
        mon_rect = sword_image.get_rect(center=Center)
        screen.blit(sword_image,mon_rect)  
    elif num == 8:
        mon_rect = spring_image.get_rect(center=Center)
        screen.blit(spring_image,mon_rect)  

###################################### BATTLING #########################################

# the main function when you encounter a monster
def encountering_monster(Monster):
    global flag

    pygame.mixer.music.load('encounter.ogg')
    pygame.mixer.music.play(-1)

    full_hp = Monster.hp
    mon_image = pygame.transform.scale(pygame.image.load(Monster.pic)\
                                        ,(160,160))
    mon_rect = mon_image.get_rect(center=[320,240])
    speed = [1,1]
    
    start = time.time()
    
    while Monster.hp > 0 and flag:
        
        # monster hit player once per sec
        if time.time() - start > 1:
            player.hp -= Monster.atk

            start = time.time()
            if player.hp <= 0:
                player.hp = 100
                player.death += 1
                break
                
            background()
            
            atk_rect = atk_image.get_rect(center=[int(uniform(hero_rect.left,\
                                                              hero_rect.right)),\
                                                  int(uniform(hero_rect.top,\
                                                              hero_rect.bottom))])
            screen.blit(atk_image, atk_rect)
        
        else:
            background()
        
        skillbutton_rect = skillbutton_image.get_rect(center=[560,440])
        screen.blit(skillbutton_image, skillbutton_rect)
        
        skillbutton_rect = skillbutton_image.get_rect(center=[560,400])
        screen.blit(skillbutton_image, skillbutton_rect)

        skillbutton_rect = skillbutton_image.get_rect(center=[560,360])
        screen.blit(skillbutton_image, skillbutton_rect)
        
        skill_button = {
                  '(1)Attack: 0 MP':(560,360),\
                  '(2)Light: 10 MP':(560,400),\
                  '(3)Heal:  30 MP':(560,440)}
        
        for my_text, text_pos in skill_button.items():
            text_surface = my_font.render(my_text, True, white)
            rect = text_surface.get_rect(center=text_pos)
            screen.blit(text_surface, rect)

        mon_rect = mon_rect.move(speed)
        
        mon_info = 'lv: '+str(Monster.lv)+'  '+Monster.name
        info_button = {mon_info:((mon_rect.right+mon_rect.left)/2,\
                                   mon_rect.top-20)}
        
        if mon_rect.left < 220 or mon_rect.right > width-220:
            speed[0] = -speed[0]
        if mon_rect.top < 130 or mon_rect.bottom > height-130:
            speed[1] = -speed[1]
        
        # add the rectangle containing the monster to this screen
        screen.blit(mon_image, mon_rect)
        
        # show monster's hp with rect
        pygame.draw.rect(screen,green,((mon_rect.right+mon_rect.left)/2-Monster.hp/2,\
                                       mon_rect.top-10,\
                                       Monster.hp,
                                       10),0)
        
        
        # add the info of monster to this screen
        for my_text, text_pos in info_button.items():
            text_surface = my_font.render(my_text, True, white)
            rect = text_surface.get_rect(center=text_pos)
            screen.blit(text_surface, rect)
            
        attack = check_attack(mon_rect)
        #if check_attack() == 1:
            #Monster.hp = 0
        if attack == 1:
            Monster.hp -= player.atk

            atk_rect = atk_image.get_rect(center=[int(uniform(mon_rect.left,\
                                                              mon_rect.right)),\
                                                  int(uniform(mon_rect.top,\
                                                              mon_rect.bottom))])
            screen.blit(atk_image, atk_rect)
            #print("Monster's remaining HP: "+str(Monster.hp))

        elif attack == 2:
            #print("Lighting")
            if player.mp >= 10:
                Monster.hp -= player.atk * 1.5
                player.mp -=10
                
                screen.blit(skill_image, skill_rect)
                
        elif attack == 3:
            #print("Heal")
            if player.mp >= 30:
                player.mp -= 30
                
                player.hp += 50
                if player.hp > 100:
                    player.hp = 100
                
                heal_rect = heal_image.get_rect(center=[int(uniform(hero_rect.left,\
                                                              hero_rect.right)),\
                                                  int(uniform(hero_rect.top,\
                                                              hero_rect.bottom))])
                screen.blit(heal_image, heal_rect)
 
        pygame.display.flip()
        
    if Monster.hp <= 0:
        Monster.hp = full_hp
        Monster.lv += 1
        Monster.hp += (Monster.mid-1)*4
    
    
        player.exp += Monster.exp
        if player.exp >= 100:
            player.lv += 1
            player.hp = 100
            player.mp = 100
            player.atk += 2
            player.exp -= 100
            
    else:
        Monster.hp = full_hp
        screen.blit(dead_image, dead_rect)

    pygame.mixer.music.stop()
    
# using pygame event to check if you are attacking
def check_attack(rect):
    global flag,display_mode
    for event in pygame.event.get():
        if(event.type is MOUSEBUTTONDOWN):
            pos = pygame.mouse.get_pos()
        elif(event.type is MOUSEBUTTONUP):
            pos = pygame.mouse.get_pos()
            x,y = pos
            
            if y > 360-15 and y < 360+15:
                if x > 560-50 and x < 560+50:
                    return 1
            
            if y > 400-15 and y < 400+15:
                if x > 560-50 and x < 560+50:
                    return 2
                    
            if y > 440-15 and y < 440+15:
                if x > 560-50 and x < 560+50:
                    return 3

            if y > rect.top and y < rect.bottom:
                if x > rect.left and x < rect.right:
                    return 1

            if y > 0 and y < 20:
                if x > 620 and x < 640:
                    flag = False

            if y > map_rect.top and y < map_rect.bottom:
                if x > map_rect.left and x < map_rect.right:
                    display_mode = not display_mode


	elif event.type == pygame.KEYDOWN:
	    if event.key == pygame.K_1:
		return 1
	    elif event.key == pygame.K_2:
		return 2
	    elif event.key == pygame.K_3:
		return 3

    return 0

#################################### Moving #########################################

# using pygame event to check your commands for moving
def check_direction():
    global flag,display_mode
    for event in pygame.event.get():
        if(event.type is MOUSEBUTTONDOWN):
            pos = pygame.mouse.get_pos()
        elif(event.type is MOUSEBUTTONUP):
            pos = pygame.mouse.get_pos()
            x,y = pos
            
            if y > forward_rect.top and y < forward_rect.bottom:
                if x > forward_rect.left and x < forward_rect.right:
                    Forward()
            
            if y > backward_rect.top and y < backward_rect.bottom:
                if x > backward_rect.left and x < backward_rect.right:
                    Backward()
                    
            if y > right_rect.top and y < right_rect.bottom:
                if x > right_rect.left and x < right_rect.right:
                    Right()
                    
            if y > left_rect.top and y < left_rect.bottom:
                if x > left_rect.left and x < left_rect.right:
                    Left()

            if y > 0 and y < 20:
                if x > 620 and x < 640:
                    flag = False

            if y > map_rect.top and y < map_rect.bottom:
                if x > map_rect.left and x < map_rect.right:
                    display_mode = not display_mode
	  

	elif event.type == pygame.KEYDOWN:
	    if event.key == pygame.K_w:
		Forward()
	    elif event.key == pygame.K_s:
		Backward()
	    elif event.key == pygame.K_a:
		Left()
	    elif event.key == pygame.K_d:
		Right()
            elif event.key == pygame.K_q:
                sLeft()
            elif event.key == pygame.K_e:
                sRight()

def Forward():
    global pos,move,move_start
    if pos[2] == 1:
        for i in range(5):
	    for j in range(4):
	    	map[i+1][j+1] = map[i+1][j+2]
	    map[i+1][5] = 1
	rand = int(uniform(1.0,9.0))
	if rand <= 8:
	    map[int(uniform(1.0,6.0))][5] = rand
    elif pos[2] == 2:
        for i in range(5):
	    for j in range(4):
	    	map[5-j][i+1] = map[4-j][i+1]
	    map[1][i+1] = 1
	rand = int(uniform(1.0,9.0))
	if rand <= 8:
	    map[1][int(uniform(1.0,6.0))] = rand
    elif pos[2] == 3:
        for i in range(5):
	    for j in range(4):
	    	map[i+1][5-j] = map[i+1][4-j]
	    map[i+1][1] = 1
	rand = int(uniform(1.0,9.0))
	if rand <= 8:
	    map[int(uniform(1.0,6.0))][1] = rand
    elif pos[2] == 4:
        for i in range(5):
	    for j in range(4):
	    	map[j+1][i+1] = map[j+2][i+1]
	    map[5][i+1] = 1
	rand = int(uniform(1.0,9.0))
	if rand <= 8:
	    map[5][int(uniform(1.0,6.0))] = rand
        
    set_direction(1,-1)
    set_direction(2,1)
    move = 1
    move_start = time.time()  

def Backward():
    global pos,move,move_start
    if pos[2] == 1:
        for i in range(5):
	    for j in range(4):
	    	map[i+1][5-j] = map[i+1][4-j]
	    map[i+1][1] = 1
	rand = int(uniform(1.0,9.0))
	if rand <= 8:
	    map[int(uniform(1.0,6.0))][1] = rand
    elif pos[2] == 2:
        for i in range(5):
	    for j in range(4):
	    	map[j+1][i+1] = map[j+2][i+1]
	    map[5][i+1] = 1
	rand = int(uniform(1.0,9.0))
	if rand <= 8:
	    map[5][int(uniform(1.0,6.0))] = rand
    elif pos[2] == 3:
        for i in range(5):
	    for j in range(4):
	    	map[i+1][j+1] = map[i+1][j+2]
	    map[i+1][5] = 1
	rand = int(uniform(1.0,9.0))
	if rand <= 8:
	    map[int(uniform(1.0,6.0))][5] = rand
    elif pos[2] == 4:
        for i in range(5):
	    for j in range(4):
	    	map[5-j][i+1] = map[4-j][i+1]
	    map[1][i+1] = 1
	rand = int(uniform(1.0,9.0))
	if rand <= 8:
	    map[1][int(uniform(1.0,6.0))] = rand

    set_direction(1,1)
    set_direction(2,-1)
    move = 1
    move_start = time.time()

def Right():
    global pos,move,move_start
    if pos[2] == 1:
        pos[2] = 4
    else:
        pos[2] -= 1

    set_direction(1,1)
    set_direction(2,1)
    move = 2
    move_start = time.time()

def Left():
    global pos,move,move_start
    if pos[2] == 4:
        pos[2] = 1
    else:
        pos[2] += 1
    set_direction(2,-1)
    set_direction(1,-1)
    move = 2
    move_start = time.time()

# make a small right turn
def sRight():
    global move,move_start
    set_direction(1,1)
    set_direction(2,1)
    
    time.sleep(0.1)
    set_direction(1,0)
    set_direction(2,0)

# make a small left turn
def sLeft():
    global move,move_start
    set_direction(2,-1)
    set_direction(1,-1)
    
    time.sleep(0.1)
    set_direction(1,0)
    set_direction(2,0)

############################## generate title page ################################

def check_click():
    for event in pygame.event.get():
        if(event.type is MOUSEBUTTONDOWN):
            pos = pygame.mouse.get_pos()
        elif(event.type is MOUSEBUTTONUP):
            pos = pygame.mouse.get_pos()
            x,y = pos
	    return 1

    return 0

pygame.mixer.music.load('Netherplace.ogg')
pygame.mixer.music.play(-1)
 
mon_list = np.array([1,2,3,4,5,1,2])
mon_pos = np.array([[0,480-25],[-120,480-25],[-240,480-25],[-360,480-25],\
	   [-480,480-25],[-600,480-25],[-720,480-25]])
mon_spd = np.array([[1,-uniform(1.0,15.0)],[1,-uniform(1.0,15.0)],\
	[1,-uniform(1.0,15.0)],[1,-uniform(1.0,15.0)],\
	[1,-uniform(1.0,15.0)],[1,-uniform(1.0,15.0)],\
	[1,-uniform(1.0,15.0)]])

while True:
    # fill the screen with black
    screen.fill(black)

    screen.blit(pi_image,pi_rect)
    screen.blit(ar_image,ar_rect)
    screen.blit(game_image,game_rect)

    if check_click():
	break

    for i in range(len(mon_list)):
	if mon_list[i] == 1:
	    mon_img = pygame.image.load(bat.pic)
	elif mon_list[i] == 2:
	    mon_img = pygame.image.load(centaur.pic)
	elif mon_list[i] == 3:
	    mon_img = pygame.image.load(angryboy.pic)
	elif mon_list[i] == 4:
	    mon_img = pygame.image.load(pumpkin.pic)
	elif mon_list[i] == 5:
	    mon_img = pygame.image.load(dragon.pic)

	#mon_img = pygame.image.load(mon_list[i].pic)
        mon_rect = mon_img.get_rect(center=(mon_pos[i][0],mon_pos[i][1]))

	# make monster jump
	if mon_rect.bottom > 480:
	    mon_spd[i][1] = -uniform(1.0,15.0)

	mon_rect = mon_rect.move(mon_spd[i])
	mon_spd[i][1] += 0.5

        screen.blit(mon_img,mon_rect)

	mon_pos[i][0] = mon_rect.center[0]
	mon_pos[i][1] = mon_rect.center[1]

    if mon_pos[0][0]-25 > 640:
	for i in range(len(mon_list)-1):
	    mon_list[i] = mon_list[i+1]
	    mon_pos[i] = mon_pos[i+1]
	    mon_spd[i] = mon_spd[i+1]
	ran_mon = int(uniform(1.0,6.0))
	if ran_mon == 1:
	    mon_list[len(mon_list)-1] = 1
	elif ran_mon == 2:
	    mon_list[len(mon_list)-1] = 2
	elif ran_mon == 3:
	    mon_list[len(mon_list)-1] = 3
	elif ran_mon == 4:
	    mon_list[len(mon_list)-1] = 4
	elif ran_mon == 5:
	    mon_list[len(mon_list)-1] = 5
	mon_pos[len(mon_list)-1][0] = mon_pos[len(mon_list)-2][0]-120
	mon_pos[len(mon_list)-1][1] = 480-25
	mon_spd[len(mon_list)-1][0] = 1
	mon_spd[len(mon_list)-1][1] = -uniform(1.0,15.0)

    # display the whole screen
    pygame.display.flip()
    time.sleep(0.03)

############################## input name page #####################################

NM_Font = pygame.font.Font(None,50)
done = False
name = ''
input_box = pygame.Rect(240,300,160,50)

Button_Enter = 'ENTER'
Enter_Font = pygame.font.Font(None,40)
Enter_surface = Enter_Font.render(Button_Enter,True,white)
Enter_box = pygame.Rect(500,430,100,40)

Text1 = 'Hi Player:'
Text2 = 'Write down your name and start a great adventure.'
Text_Font = pygame.font.Font(None,30)
Text1_surface = Text_Font.render(Text1,True,white)
Text2_surface = Text_Font.render(Text2,True,white)

while not done:
    for event in pygame.event.get():
	if event.type == pygame.KEYDOWN:
	    if event.key == pygame.K_BACKSPACE:
		name = name[:-1]
	    elif event.key == pygame.K_RETURN:
		done = True
	    else:
		if len(name) <= 7:
		    name += event.unicode
        elif(event.type is MOUSEBUTTONDOWN):
            pos = pygame.mouse.get_pos()
        elif(event.type is MOUSEBUTTONUP):
            pos = pygame.mouse.get_pos()
            x,y = pos

            if x > 500 and x < 600:
            	if y > 430 and y < 470:
                    done = True

    # fill the screen with black
    screen.fill(black)

    screen.blit(Text1_surface,(50,50))
    screen.blit(Text2_surface,(80,80))

    name_surface = NM_Font.render(name,True,white)
    screen.blit(name_surface,(245,305))
    pygame.draw.rect(screen,white,input_box,2)

    screen.blit(Enter_surface,(505,435))
    pygame.draw.rect(screen,white,Enter_box,2)

    pygame.display.flip()
    time.sleep(0.01)

pygame.mixer.music.stop()

################################ main game ####################################

# Save the position and orientation of player
# ori:
# 1 -- facing right
# 2 -- facing up
# 3 -- facing left
# 4 -- facing down
pos = np.array([3,3,1])

# initialize map
map = map_generator()

move = 0
move_start = 0

# flag is the global value controling the running of pygame
# it's default value is True
flag = True

# use flag to control the running, if flag value is False, end the loop
while flag:
    facing = check_facing(pos,map)
       
    # generate the background
    background()
    
    if move == 0:
    	if map[pos[0],pos[1]] == 1:
            # generate monsters
            generate_monster(facing[0],[100,240])
            generate_monster(facing[1],[320,200])
            generate_monster(facing[2],[540,240])
    	elif map[pos[0],pos[1]] == 2:
            encountering_monster(bat)
            map[pos[0],pos[1]] = 1
    	elif map[pos[0],pos[1]] == 3:
            encountering_monster(centaur)
            map[pos[0],pos[1]] = 1
    	elif map[pos[0],pos[1]] == 4:
            encountering_monster(angryboy)
            map[pos[0],pos[1]] = 1
    	elif map[pos[0],pos[1]] == 5:
            encountering_monster(pumpkin)
            map[pos[0],pos[1]] = 1
    	elif map[pos[0],pos[1]] == 6:
            encountering_monster(dragon)
            map[pos[0],pos[1]] = 1
	elif map[pos[0],pos[1]] == 7:
	    player.atk += 10
	    map[pos[0],pos[1]] = 1
	elif map[pos[0],pos[1]] == 8:
	    player.hp = 100
	    player.mp = 100
	    map[pos[0],pos[1]] = 1

    	draw_movebutton()
    	check_direction()

    elif move == 1:
	if time.time()-move_start > 1:
    	    set_direction(1,0)
    	    set_direction(2,0)
	    move = 0
    elif move == 2:
	if time.time()-move_start > 0.5:
    	    set_direction(1,0)
    	    set_direction(2,0)
	    move = 0	    
    
    # display the whole screen
    pygame.display.flip()
    time.sleep(0.01)

################################## END PAGE ##################################

pygame.mixer.music.load('Netherplace.ogg')
pygame.mixer.music.play(-1)

Text1 = 'Thank You For Playing!'
Text2 = 'Made By:'
Text3 = 'Mengde Wu'
Text4 = 'Yexiang Chang'
Text_Font = pygame.font.Font(None,30)
Text1_surface = Text_Font.render(Text1,True,white)
Text2_surface = Text_Font.render(Text2,True,white)
Text3_surface = Text_Font.render(Text3,True,white)
Text4_surface = Text_Font.render(Text4,True,white)

mon_list = np.array([1,2,3,4,5,1,2])
mon_pos = np.array([[0,480-25],[-120,480-25],[-240,480-25],[-360,480-25],\
	   [-480,480-25],[-600,480-25],[-720,480-25]])
mon_spd = np.array([[1,-uniform(1.0,15.0)],[1,-uniform(1.0,15.0)],\
	[1,-uniform(1.0,15.0)],[1,-uniform(1.0,15.0)],\
	[1,-uniform(1.0,15.0)],[1,-uniform(1.0,15.0)],\
	[1,-uniform(1.0,15.0)]])

while True:
    # fill the screen with black
    screen.fill(black)

    screen.blit(Text1_surface,(80,60))
    screen.blit(Text2_surface,(400,80))
    screen.blit(Text3_surface,(410,100))
    screen.blit(Text4_surface,(410,120))

    if check_click():
	break

    for i in range(len(mon_list)):
	if mon_list[i] == 1:
	    mon_img = pygame.image.load(bat.pic)
	elif mon_list[i] == 2:
	    mon_img = pygame.image.load(centaur.pic)
	elif mon_list[i] == 3:
	    mon_img = pygame.image.load(angryboy.pic)
	elif mon_list[i] == 4:
	    mon_img = pygame.image.load(pumpkin.pic)
	elif mon_list[i] == 5:
	    mon_img = pygame.image.load(dragon.pic)

	#mon_img = pygame.image.load(mon_list[i].pic)
        mon_rect = mon_img.get_rect(center=(mon_pos[i][0],mon_pos[i][1]))

	# make monster jump
	if mon_rect.bottom > 480:
	    mon_spd[i][1] = -uniform(1.0,15.0)

	mon_rect = mon_rect.move(mon_spd[i])
	mon_spd[i][1] += 0.5

        screen.blit(mon_img,mon_rect)

	mon_pos[i][0] = mon_rect.center[0]
	mon_pos[i][1] = mon_rect.center[1]

    if mon_pos[0][0]-25 > 640:
	for i in range(len(mon_list)-1):
	    mon_list[i] = mon_list[i+1]
	    mon_pos[i] = mon_pos[i+1]
	    mon_spd[i] = mon_spd[i+1]
	ran_mon = int(uniform(1.0,6.0))
	if ran_mon == 1:
	    mon_list[len(mon_list)-1] = 1
	elif ran_mon == 2:
	    mon_list[len(mon_list)-1] = 2
	elif ran_mon == 3:
	    mon_list[len(mon_list)-1] = 3
	elif ran_mon == 4:
	    mon_list[len(mon_list)-1] = 4
	elif ran_mon == 5:
	    mon_list[len(mon_list)-1] = 5
	mon_pos[len(mon_list)-1][0] = mon_pos[len(mon_list)-2][0]-120
	mon_pos[len(mon_list)-1][1] = 480-25
	mon_spd[len(mon_list)-1][0] = 1
	mon_spd[len(mon_list)-1][1] = -uniform(1.0,15.0)

    # display the whole screen
    pygame.display.flip()
    time.sleep(0.03)

pygame.mixer.music.stop()

############################ Clean Up ##################################

s1.stop()
s2.stop()
GPIO.cleanup()
pygame.quit()
cv2.destroyAllWindows()