No Internet (Commodore VIC 20) by Huffelduff

     Title: No Internet

  Platform: Unexpanded Commodore VIC-20

     Video: PAL/NTSC

 Interface: Keyboard only (spacebar = jump)

 Game type: Arcade

Written by: E W de Villiers

  Released: 14 March 2024

The Plot: 

---------

This game is based upon the dinosaur jumping over cacti game which one gets in the web browser Google Chrome which can be played when there is no internet connection available.

In the past three weeks or so I've seen another version for an 8-bit platform being released and so here is the Vic-20 version.

Mechanics:

----------

jump = spacebar

press any keyboard key to restart the game

Every time you jump a point is deducted. If you hit a cactus or your score goes to zero the game ends.

Greetings

Huffelduff (User handle on the VIC-20 Denial forum)

'NO INTERNET' SOURCE CODE:

-------------------------------------------------------------------------------- <- 80 Character line limit
0 v=36864:fOi=0to31:rEd:pO7168+i,d:pO7424+i,0:nE:pOv+5,255:pOv+14,15:pOv+15,8
1 ?cH(5);cH(147);cH(18):fOi=3to11:pO7947+i,2:nE:y2=7932:y3=y2:a=1:df=0
2 i=pE(197):?cH(19);cH(18);spc(6);"s:";a;cH(157);" ":a=a+1+2*(i=32):y4=y3
3 y3=y2+(22*(i=32)):ca=32-(29*int(rN(0)*(1.1+df))):df=df+0.001:pO7935,ca
4 fOi=0to2:pO7928+i,pE(7929+i):nE:pOy4,32:pO7931,pE(7932):pO7932,pE(7933)
5 cd=pE(y3):pOy3,(aaN1):fOi=2to5:pO7931+i,pE(7932+i):nE:if(cd<>3)aN(a>=0)then2
6 h=(a*-1*(a>=h))+(h*-1*(a<h)):?cH(19);cH(18);cH(17);spc(6);"h:";h-1
7 ?cH(19):fOi=1to14:?spc(22);:nE:?spc(2);cH(18);"still no internet!":dA 30,94
8 fOi=50to0step-1:pOv+10,200+i:nE:pOv+10,0:wA197,64,64:gO1:dA 152,152,190,250,88
9 dA 36,30,94,152,152,190,250,112,24,255,0,0,0,0,0,0,0,0,8,24,26,90,94,120,24
-------------------------------------------------------------------------------- <- 80 Character line limit

Variables used within the program:

----------------------------------

 v = start of the VIC chip registers 

 a = score

 h = hi score

y2 = player (dino) start location

y3 = player location jumping or not

y4 = old player location

cd = collision detection variable

ca = cactus or blank character for rightmost character

df = difficulty

 i = general purpose (for loops and such)

--------------------------------------------------------------------------------

Analysis:

---------

LINE: 0 v=36864:fOi=0to31:rEd:pO7168+i,d:pO7424+i,0:nE:pOv+5,255:pOv+14,15:pOv+15,8

----

fOi=0to31:rEd:pO7168+i,d:pO7424+i,0:nE - load the 4 custom characters into the start of character memory and load four blank character into character position 32 (space) and on

   - only one blank character (32) is needed but because only one 'for' loop is used four characters are blanked

pOv+5,255 - change the screen character memory location 

pOv+14,15 - set the sound volume to full (15)

pOv+15,8  - set black border and black background

--------------------------------------------------------------------------------

LINE: 1 ?cH(5);cH(147);cH(18):fOi=3to11:pO7947+i,2:nE:y2=7932:y3=y2:a=1:df=0

----

?cH(5);cH(147);cH(18):fOi=3to11:pO7947+i,2nE - print color to white, clear screen, inverse characters, draw the ground line

  y2=7932:y3=y2:a=1:df=0 - initialize some variables

--------------------------------------------------------------------------------

Core loop: line 2 to 5

----------------------

LINE: 2 i=pE(197):?cH(19);cH(18);spc(6);"s:";a;cH(157);" ":a=a+1+2*(i=32):y4=y3

----

                               i=pE(197) - get keyboard input

?cH(19);cH(18);spc(6);"s:";a;cH(157);" " - draw score line

                          a=a+1+2*(i=32) - update score by adding one, if jumping subtract one

                                   y4=y3 - store old player position

LINE: 3 y3=y2+(22*(i=32)):ca=32-(29*int(rN(0)*(1.1+df))):df=df+0.001:pO7935,ca

----

             y3=y2+(22*(i=32)) - update player location jumping or not

ca=32-(29*int(rN(0)*(1.1+df))) - generate a cactus or a blank as rightmost character

   df=df+0.001 - increase difficulty

pO7935,ca - draw the rightmost character

LINE: 4 fOi=0to2:pO7928+i,pE(7929+i):nE:pOy4,32:pO7931,pE(7932):pO7932,pE(7933)

-----

fOi=0to2:pO7928+i,pE(7929+i):nE - scroll the characters left of the dino

pOy4,32 - draw a blank over old dino position

pO7931,pE(7932):pO7932,pE(7933) - scroll from dino one left, scroll from one right of dino to dino

LINE: 5 cd=pE(y3):pOy3,(aaN1):fOi=2to5:pO7931+i,pE(7932+i):nE:if(cd<>3)aN(a>=0)then2

----

          cd=pE(y3):pOy3,(aaN1) - store collision detection value, draw the player character

fOi=2to5:pO7931+i,pE(7932+i):nE - scroll the characters right of the dino

         if(cd<>3)aN(a>=0)then2 - if no cactus has been hit or the score is not less than 0 loop back to 2, else drop through for game over

--------------------------------------------------------------------------------

LINE: 6 h=(a*-1*(a>=h))+(h*-1*(a<h)):?cH(19);cH(18);cH(17);spc(6);"h:";h-1

----

- update the high score and then display it

--------------------------------------------------------------------------------

LINE: 7 ?cH(19):fOi=1to14:?spc(22);:nE:?spc(2);cH(18);"still no internet!":dA 30,94

- display "still no internet"

- start of character data

--------------------------------------------------------------------------------

LINE: 8 fOi=50to0step-1:pOv+10,200+i:nE:pOv+10,0:wA197,64,64:gO1:dA 152,152,190,250,88

fOi=50to0step-1:pOv+10,200+i:nE - game over sound

wA197,64,64 - wait for a keypress

  dA 152,152,190,250,88 - character data

--------------------------------------------------------------------------------

LINE: 9 dA 36,30,94,152,152,190,250,112,24,255,0,0,0,0,0,0,0,0,8,24,26,90,94,120,24

- character data

--------------------------------------------------------------------------------