17 byte demo!

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bitshifter

Joined: 04 Dec 2007
Posts: 796
Location: Massachusetts, USA

bitshifter 23 Apr 2009, 23:45

asmdemon wrote:

Here is my compo entry for EFnet's ASM compo #9. Very similar program. The actual entry, hell, won that competition. I modified it one day to include exit on keypress.

Hello asmdemon
Funny that you should mention this.
Indeed your HELL demo was my inspiration for this cool micro.
I figured i could slim it down a bunch while using the same render algo.

_________________
Coding a 3D game engine with fasm is like trying to eat an elephant,
you just have to keep focused and take it one 'byte' at a time.

23 Apr 2009, 23:45

catafest

Joined: 05 Aug 2010
Posts: 131

catafest 16 Jan 2011, 16:53

Code:

use16
org 0x100
mov ah,0x00
mov ax,0x13 
int 0x10 
push word 0xA000
mov es, ax
mov ax,0
mov di,ax
mov dl,16
mov[es:di],dl
pop es 
paint: 
add cx,ax
stosd
loop paint
inc ax
jmp paint
mov ax,3
int 10h

what do think about that ? Smile

16 Jan 2011, 16:53

Coty

Joined: 17 May 2010
Posts: 553
Location: ␀

Coty 16 Jan 2011, 18:20

Nice

[EDIT2] 20 bytes Very Happy

Code:

  use16
  org  0x100
  mov  ax, 0x13
  int  0x10
  push word 0xA000
  xor  di, di
  pop  es
paint:
    add  cx, ax
    .loop:
      stosd
      loop .loop
    inc  ax
    jmp  paint

I honestly like it more with stosw instead of stosd, witch makes it 19 bytes, but it does not look the same as the lines are not as well spaced.

[EDIT3] Just realized that you can remove "xor di, di" and it will compile to 17bytes and still work under winXP... Witch makes it a 17byte demo...

[EDIT4] If you follow this trick here: http://board.flatassembler.net/topic.php?p=81875#81875

You can get it to 15 bytes and still working...

Code:

  use16
  org  0x100
  mov  ax, 0x0013
  int  0x10
  les  ax, [bx]     ; Trick I stoll from this thread...
paint:
    add  cx, ax
    .loop:
      stosw
      loop .loop
    inc  ax
    jmp  paint

OK ... I'm done...

_________________
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16 Jan 2011, 18:20

bitshifter

Joined: 04 Dec 2007
Posts: 796
Location: Massachusetts, USA

bitshifter 17 Jan 2011, 04:33

Assuming regs are zero'ed at startup, yes.
Just be sure to warn people of this...

17 Jan 2011, 04:33

16bitPM

Joined: 08 Jul 2011
Posts: 30

16bitPM 29 Mar 2012, 19:28

catafest wrote:

Code:

use16
org 0x100
mov ah,0x00
mov ax,0x13 
int 0x10 
push word 0xA000
mov es, ax
mov ax,0
mov di,ax
mov dl,16
mov[es:di],dl
pop es 
paint: 
add cx,ax
stosd
loop paint
inc ax
jmp paint
mov ax,3
int 10h

what do think about that ? Smile

Errr?

Why the first mov ah,0?

Why do you write to an unused area of the interrupt vector table?
(ax = 13 ; ax → es ; di=0 so address 130h ?!?)
So on my computer you change INT vector 4C from F000:1060 to F000:1016 Rolling Eyes

Why the exit code after jmp which is never reached?

29 Mar 2012, 19:28

16bitPM

Joined: 08 Jul 2011
Posts: 30

16bitPM 07 Apr 2012, 20:44

Same code with palette reprogramming, in 28 bytes:

Code:

mov al,13
int 10
mov dx,03c8h
mov al,0
out dx,al
inc dx
loop1: out dx,al
out dx,al
out dx,al
inc al
jnz loop1
les bx,[bx]
adc ax,cx
stosb
loop 114
inc ax
jmp 114

07 Apr 2012, 20:44

Picnic

Joined: 05 May 2007
Posts: 1418
Location: Piraeus, Greece

Picnic 27 Aug 2012, 13:40

I found these two 32byte demos on frag's blog.
Take a look.

Moss
Oil

27 Aug 2012, 13:40

freecrac

Joined: 19 Oct 2011
Posts: 117
Location: Germany Hamburg

freecrac 29 Aug 2012, 05:35

neville wrote:

Can anybody write a paged VESA version of my linear VESA code above in less than 66 bytes? I don't expect it to run faster, just smaller code :!:

Example for to set the page with a "call far"-instruction to the vesa routine:

Code:

          mov      eax, DWORD PTR[di+0Ch] ; make sure that DS:DI points to the modeinfobuffer before
     and      eax, eax
   jz  ERROR
   mov     DWORD PTR cs:[PAGESET], eax
;--------------------------------------


;--------------------------------------
       cmp      dx, bp               ; compare pagenumbers
         jz  short NOSET               ; same pagenumber?
    xor      bx, bx
     mov      bp, dx               ; save the actual number of the page
;--------------------------
          DB 9Ah                        ; CALL FAR: SETPAGE
PAGESET   DD ?
;--------------------------
NOSET:                                  ; Now we can draw our pixel

Dirk

29 Aug 2012, 05:35

Lucy Berie

Joined: 08 Dec 2012
Posts: 13

Lucy Berie 09 Dec 2012, 03:01

Hey, I have a funny code (Modified a bit)

Code:

org 100h

 mov al,13h
 int 10h
 les ax,[bx]
paint:
 sbb ax,di
 stosb
 add di,3
 jmp paint

(Trying implementing some basic assembly calculation commands...) Wink

Or :

Code:

org 100h

 mov al,13h
 int 10h
 les ax,[bx]
paint:
 sbb ax,di
 stosb
 add di,5
 jmp paint

Code:

org 100h

 mov al,13h
 int 10h
 les ax,[bx]
paint:
 sbb ax,di
 stosb
 add di,7
 jmp paint

Looks much nicer... Very Happy

Ok,

Code:

 
mov al,13h 
int 10h

I think these code are used to call graphics...

Code:

 les ax,[bx]
......................
 sbb ax,di
 stosb

I don't really understand this...

09 Dec 2012, 03:01

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