Life with pointers

[Gary Barnes]

This is my small, speedy implementation of Conways game of life.
I became obsessed with speed while writing this and this is the result.
The only rule that I set myself was 'no assembler', all PB.

' Conway's Game of Life

#COMPILE EXE "lifepbw8.exe"
#DIM ALL
#REGISTER ALL

DECLARE FUNCTION IsWindow LIB "USER32.DLL" ALIAS "IsWindow" (BYVAL hWnd AS DWORD) AS LONG

FUNCTION PBMAIN() AS LONG
LOCAL w,h,ncw,nch,gwin,z,sum,rsx,rsy,x,y,w1,h1,gdc, totpixel AS LONG
LOCAL tg(), ng() AS BYTE
LOCAL tgptr, ngptr AS BYTE PTR

w = 800
h = 600

totpixel = (w-1) * (h-1)
DIM tG(totpixel)             ' current generation
DIM nG(totpixel)             ' next generation

RANDOMIZE TIMER              ' reset the random number generator
DESKTOP GET CLIENT TO ncw,nch
GRAPHIC WINDOW "Look! - It's alive",(ncw-w)/2,(nch-h)/2,w,h TO gwin
GRAPHIC ATTACH gwin,0,REDRAW

GRAPHIC COLOR %WHITE,RGB(0,0,64)
                              ' main program loop
FOR y = w+1 TO totpixel - w   ' seed this generation array randomly
        z = RND(1,17)         ' change from 10 to whatever you like - 2 is too crowded
        IF z=1 THEN tG(y) = 1 ' between 10 and 50 odd gives a pleasing result
NEXT

y = totpixel - w   
ngptr = VARPTR(ng(0))
tgptr = VARPTR(tg(0))
DO
   IF IsWindow(gwin) = 0 THEN EXIT DO
   x = y
   DO
        IF @tgptr[x] THEN GRAPHIC SET PIXEL (x MOD w , x\w)
        sum = @tgptr[x-1-w] + @tgptr[x-w] + @tgptr[x+1-w] +_
              @tgptr[x-1]   + @tgptr[x+1] +_                ' this routine just adds up the number of occupied cells
              @tgptr[x-1+w] + @tgptr[x+w] + @tgptr[x+1+w]   ' around the one of interest - tg(x,y)
        IF sum = 2 THEN @ngptr[x] = @tgptr[x]
        IF sum = 3 THEN INCR @ngptr[x]
        DECR x
   LOOP UNTIL x = 0

   MAT tg()=ng()
   MAT ng() = ZER

   GRAPHIC REDRAW                                              ' all done display the new page and return
   GRAPHIC CLEAR
LOOP
END FUNCTION

As far as life itself is concerned, the rules can be found in other posts.
I offer this up for your amusement.

By the way, it is quite CPU intensive

Cheers

[Marco Pontello]

[deleted - Didn't notice it was in the Source code forum]

[Gary Barnes]

Code Correction

Many thanks to Jordi Vallès who pointed out an error in the code.
The corrected source is below.
He found that the program crashed every now and then because of an out of bounds array error.
The fix is in the inner do loop terminating conditions.
A small side effect is that the program is slightly faster

' Conway's Game of Life

#COMPILE EXE "lifepbw8.exe"
#DIM ALL
#REGISTER ALL

DECLARE FUNCTION IsWindow LIB "USER32.DLL" ALIAS "IsWindow" (BYVAL hWnd AS DWORD) AS LONG

FUNCTION PBMAIN() AS LONG
LOCAL w,h,ncw,nch,gwin,z,sum,rsx,rsy,x,y,w1,h1,gdc, totpixel AS LONG
LOCAL tg(), ng() AS BYTE
LOCAL tgptr, ngptr AS BYTE PTR

w = 800
h = 600

totpixel = (w-1) * (h-1)
DIM tG(totpixel)             ' current generation
DIM nG(totpixel)             ' next generation

RANDOMIZE TIMER              ' reset the random number generator
DESKTOP GET CLIENT TO ncw,nch
GRAPHIC WINDOW "Look! - It's alive",(ncw-w)/2,(nch-h)/2,w,h TO gwin
GRAPHIC ATTACH gwin,0,REDRAW

GRAPHIC COLOR %WHITE,RGB(0,0,64)
                              ' main program loop
FOR y = w+1 TO totpixel - w   ' seed this generation array randomly
        z = RND(1,17)         ' change from 10 to whatever you like - 2 is too crowded
        IF z=1 THEN tG(y) = 1 ' between 10 and 50 odd gives a pleasing result
NEXT

y = totpixel - w   
ngptr = VARPTR(ng(0))
tgptr = VARPTR(tg(0))
DO
   IF IsWindow(gwin) = 0 THEN EXIT DO
   x = y
   DO
        IF @tgptr[x] THEN GRAPHIC SET PIXEL (x MOD w , x\w)
        sum = @tgptr[x-1-w] + @tgptr[x-w] + @tgptr[x+1-w] +_
              @tgptr[x-1]   + @tgptr[x+1] +_                ' this routine just adds up the number of occupied cells
              @tgptr[x-1+w] + @tgptr[x+w] + @tgptr[x+1+w]   ' around the one of interest - tg(x,y)
        IF sum = 2 THEN @ngptr[x] = @tgptr[x]
        IF sum = 3 THEN INCR @ngptr[x]
        DECR x
   LOOP UNTIL x = w + 1

   MAT tg()=ng()
   MAT ng() = ZER

   GRAPHIC REDRAW                                              ' all done display the new page and return
   GRAPHIC CLEAR
LOOP
END FUNCTION

Thanks again Jordi.
Regards

[Gösta H. Lovgren-2]

Stasis

Thanks for the Life reminder, Gary. I've been intrigued by it ever since I copied an asm version out of a Basic mag some 30 years ago.

Anyway I doodled around your code a little and added a progression timer and Stasis Achieved state and some other clutter. It checks for changes every 100 generations and if changes are within a certain range, it achieves "Stasis". (It's not a perfect check, it may take 3 or 4 iterations to get true stability.) but fun anyway.

Next I'll think I'll pay around with using colors.

'http://www.powerbasic.com/support/pbforums/showthread.php?t=36499&highlight=life
' by Gary Barnes
#Dim All
Declare Function IsWindow Lib "USER32.DLL" Alias "IsWindow" (ByVal hWnd As Dword) As Long
#Include "WIN32API.INC"
 
 
Function PBMain() As Long
Local Seed, Stasis_Range, tmr, ctr, ctr1, ctr2, gen_total, Last_gen_total, gen_check As Long                             
Local tmr1, secs, mins, hrs As Long   
Local disp$ 
 
Local w,h,ncw,nch,gwin,z,sum,rsx,rsy,x,y,w1,h1,gdc, totpixel As Long
Local tg(), ng() As Byte
Local tgptr, ngptr As Byte Ptr
 
'w = 800
'h = 600
   Desktop Get Size To W, h 'set to max size
totpixel = (w-1) * (h-1)
Dim tG(totpixel)             ' current generation
Dim nG(totpixel)             ' next generation
 
 
'<< ************* Set starting ranges here ***********>>
Stasis_Range = totpixel * .00001 ' point at which the population appears stable
 Seed = 17 ' change from 10 to whatever you like - 2 is too crowded
  tmr = Timer
 
 
Randomize Timer              ' reset the random number generator
Desktop Get Client To ncw,nch               
 Local hdr$, Generations&
 
Graphic Window "Look! - It's alive",(ncw-w)/2,(nch-h)/2,w,h To gwin
Graphic Attach gwin,0,ReDraw
 
 
 
Graphic Color %White,RGB(0,0,64)
                              ' main program loop
For y = w+1 To totpixel - w   ' seed this generation array randomly
        z = Rnd(1, Seed)         ' change from 10 to whatever you like - 2 is too crowded
        If z=1 Then tG(y) = 1 ' between 10 and 50 odd gives a pleasing result
Next
 
y = totpixel - w   
ngptr = VarPtr(ng(0))
tgptr = VarPtr(tg(0))
Do
   If IsWindow(gwin) = 0 Then Exit Do
   x = y
   Do
        If @tgptr[x] Then Graphic Set Pixel (x Mod w , x\w)
        sum = @tgptr[x-1-w] + @tgptr[x-w] + @tgptr[x+1-w] +_
              @tgptr[x-1]   + @tgptr[x+1] +_                ' this routine just adds up the number of occupied cells
              @tgptr[x-1+w] + @tgptr[x+w] + @tgptr[x+1+w]   ' around the one of interest - tg(x,y)
        If sum = 2 Then @ngptr[x] = @tgptr[x]
        If sum = 3 Then Incr @ngptr[x]
        Decr x
   Loop Until x = w + 1
 
   Mat tg()=ng()
   Mat ng() = Zer
 
   Graphic ReDraw                                              ' all done display the new page and return
   Graphic Clear
 
   Stasis
   Set_Header
 
Loop                              
 
Graphic Window End 'otherwise could stay in mem                           
End Function
'
Macro Stasis                   
  'tG(totpixel)
  Reset gen_total
 For ctr1 = 0 To TotPixel
     gen_total = gen_total + @tgptr[ctr1] 'is pixel lit?
 Next ctr1        
 
End Macro
'
Macro set_Header  
  Incr Generations         
  tmr1 = Timer - tmr
  hrs = tmr1 \ 3600
  mins = tmr1 \ 60 - (hrs * 3600)
  secs = tmr1 -  - (hrs * 3600) - (mins * 60)
 
 If secs Then disp$ = Using$("Look - #, still live after #, Generations taking # seconds",  gen_total, Generations, secs)                  
 If mins Then disp$ = Using$("Look - #, still live after #, Generations taking # minutes and # seconds",  gen_total, Generations, mins, secs)                  
 If hrs Then disp$ = Using$("Look - #, still live after #, Generations taking # hours # minutes and # seconds",  gen_total, Generations, hrs, mins, secs)                  
 
  Dialog Set Text gwin, disp$
 
 'If population stays within Stasis_Range for 100 generations than Stasis is considered reached.     
 If Generations \ 100 = Generations / 100  Then
    If gen_Total => Last_gen_total - Stasis_Range And _
       gen_Total =< Last_gen_total + Stasis_Range Then
        SndPlaySound  "TaDa.wav", 0
 
       If secs Then disp$ = Using$("Look - #, alive and Stasis (+- # planets) reached after #, Generations took # seconds",  gen_total, Stasis_Range, Generations, secs)                  
       If mins Then disp$ = Using$("Look - #, alive and Stasis (+- # planets) reached after #, Generations took # minutes and # seconds",  gen_total, Stasis_Range, Generations, mins, secs)                  
       If hrs  Then disp$ = Using$("Look - #, alive and Stasis (+- # planets) reached after #, Generations took # hours # mins and # seconds",  gen_total, Stasis_Range, Generations, hrs, mins, secs)                  
 
       Dialog Set Text gwin, Disp$ 
       Graphic waitkey$
    End If   
 
    Last_gen_total = gen_Total 'not yet so keep going
 End If                       
End Macro
'

[Theo Gottwald]

 
REGISTER x as LONG, w AS LONG

better for this then #REGISTER ALL
which will put "Seed" and "Stasis" into the Registers.

[Gösta H. Lovgren-2]

Discussion (and code updates) on this thread:

http://www.powerbasic.com/support/pbforums/showthread.php?t=38601