Effect - Broken TV

[syntax error]

Code updated for 5.20+

Code: Select all

; broken TV

; Converted from Jeppe Nielsons Blitz 'Broken TV' code

sw.l=GetSystemMetrics_(#SM_CXSCREEN)
sh.l=GetSystemMetrics_(#SM_CYSCREEN)

#cell=72

dSW=sw/4 : dSH=sh/4
bw.f=dSW/#cell : bh.f=dSH/#cell


; setup display
ShowCursor_(0)
OpenWindow(0, 0, 0, sw, sh, "",  #PB_Window_BorderLess)

; main loop
Repeat
 DC=StartDrawing(WindowOutput(0))
 For y=0 To #cell-1
  For x=0 To #cell-1
   c=50+Random(200)
   FrontColor(RGB(c,c,c))
   Box(x*bw,y*bh,bw,bh)
  Next
 Next
 
 BitBlt_(DC , dSW,0 , dSW,dSH , DC , 0,0,#SRCCOPY)
 BitBlt_(DC , 0,dSH , dSW*2,dSH , DC , 0,0,#SRCCOPY)
 BitBlt_(DC , 0,dSH*2 , dSW*2,dSH*2 , DC , 0,0,#SRCCOPY)
 BitBlt_(DC , dSW*2,0 , dSW*2,dSH*4 , DC , 0,0,#SRCCOPY)
 
 StopDrawing()
 Delay(5)
Until GetAsyncKeyState_(#VK_ESCAPE)=-32767

; cleanup
CloseWindow(0)
ShowCursor_(1)
End

[Dreglor]

intresting,
is it me or do i see a pattern in the noise o_O
maybe i should laydown...

[benny]

@SyntaxTerror:
Nice one ... I made a TV-Noise screen, too. See here : viewtopic.php?p=44495&highlight=#44495

However, I like the fact that you achieve a pretty cool running FX without using an Open(Windowed)Screen ! Thanx for sharing...

@Dreglor:
The actual random pattern is just a 72*72 region in this example. the rest is blitted/copied.
Comment out some of the BitBlt_ commands to see what I mean.

[syntax error]

I saw a similar effect in a game once and wondered how they managed to change so many dots in realtime. Thanks to Jeppe Neilsons Blitz example code I found out how.
It's clever how the repeated blocks of the main image manage to merge together so well without too much noticable tiling.

The above example is very system friendly which means it can be used as a (broken monitor) screensaver!

[benny]

I saw a similar effect in a game once and wondered how they managed to change so many dots in realtime. Thanks to Jeppe Neilsons Blitz example code I found out how.
It's clever how the repeated blocks of the main image manage to merge together so well without too much noticable tiling.

The above example is very system friendly which means it can be used as a (broken monitor) screensaver!

I had the idea of a screensaver, too - after I wrote my version .. you can download it from my site :

http://www.weltenkonstrukteur.de/cw.html

[techjunkie]

Code: Select all

; broken TV

; Converted from Jeppe Nielsons Blitz 'Broken TV' code

[/quote]
Another Jeppe Nielson... Sweet!!  :D

[fweil]

Code updated for 5.20+

I played from this idea and obtained this (obtain 25 Mpixels/s, FPS 32, in 1024x768 on my PC) :

Code: Select all

; broken TV
  ScreenXSize = GetSystemMetrics_(#SM_CXSCREEN)
  ScreenYSize = GetSystemMetrics_(#SM_CYSCREEN)
  If InitSprite() And InitKeyboard() And OpenScreen(ScreenXSize, ScreenYSize, 32, "")
      Repeat
        FlipBuffers()
        StartDrawing(ScreenOutput())
          Address = DrawingBuffer()
          !  MOV     esi, [v_Address]             ; esi = Address. esi is the start address
          !  MOV     edi, [v_ScreenXSize]      ; edi = (ScreenXSize * ScreenYSize - ScreenXSize - ScreenYSize) * 4 + 4 + Address which is equivalent to
          !  IMUL     edi, [v_ScreenYSize]      ; edi = (ScreenXSize - 1) * (ScreenYSize - 1) * 4 + Address
          !  SUB      edi, [v_ScreenXSize]      ; edi is the last address of the drawing buffer
          !  SUB      edi, [v_ScreenYSize]      ;
          !  SAL      edi, 2                             ;
          !  ADD     edi, 4                             ;
          !  ADD     edi, esi                           ;
          ! _While_Main:                               ; While loop
            c = Random(255)                         ; c = Random(255)
            !  MOV    ebx, dword [v_c]            ; ebx = c
            !  MOV    ecx, ebx                        ; ecx = ebx
            !  SAL     ecx, 8                            ; ecx << 8
            !  ADD    ecx, ebx                        ; ecx + ebx
            !  SAL     ecx, 8                            ; ecx << 8
            !  ADD    ecx, ebx                        ; ecx + ebx, which finally corresponds to ecx = ebx << 16 + ebx << 8 + ebx or RGB(ebx, ebx, ebx) meaning RGB(c, c, c)
            !  CMP    esi, edi                          ; if esi > edi
            !  JG      _Wend_Main                   ; Break
            !  MOV    [esi], ecx                       ; PokeL(esi, ecx)
            !  INC    dword [v_NPoints]           ; NPoints + 1
            !  ADD    esi, 4                             ; esi + 4 meaning Address + 4
            !  JMP   _While_Main                     ; Wend
          ! _Wend_Main:
          BackColor(RGB(0, 0, 0))
          FrontColor(RGB(255, 255, 255))
          DrawText(10, 10, Str(FPS))
          DrawText(10, 30, Str(Points))
        StopDrawing()
        If ElapsedMilliseconds() - tz => 1000
            FPS = NFrames
            tz = ElapsedMilliseconds()
            NFrames = 0
            Points = NPoints
            NPoints = 0
        EndIf
        NFrames + 1
        ExamineKeyboard()
      Until KeyboardPushed(#PB_Key_Escape)
      CloseScreen()
  EndIf
End

[benny]

@fweil:
Nice one ... get constant 41fps on my machine with a resolution of 1024*768.