From: Richard W.M. Jones <rjones@redhat.com>
Date: Fri, 25 Oct 2019 10:49:12 +0000 (+0100)
Subject: dos2unix
X-Git-Url: http://git.annexia.org/?a=commitdiff_plain;h=9940a5f93af3b761a9de07a3994d5015424f046c;p=pyrit.git

dos2unix
---

diff --git a/pyrit.asm b/pyrit.asm
index 50c49b4..603d8da 100644
--- a/pyrit.asm
+++ b/pyrit.asm
@@ -1,244 +1,244 @@
-; Pyrit
-
-; a 256-byte intro by Rrrola <rrrola@gmail.com>
-
-; greets to everyone who's computer is too fast :)
-
-; This is loosely based on my intro 'Gem' (shown on Demobit),
-; but the code is much better.
-
-; Vector3: X right, Y down, Z forward.
-; On the FP stack it looks like {Y X Z} (Y is often used in comparisons).
-; In memory it looks like {Z X Y}, which saves a displacement byte.
-; (u'v) is the dot product: ux*vx + uy*vy + uz*vz.
-
-org 100h ; assume al=0 bx=0 sp=di=-2 si=0100h bp=09??h
-
-;Set video mode and earth+sky palette
-  dec di       ; u16[100h] = -20401, u16[10Ch] = -30515
-  mov al,13h
-  dec di       ; initial pixel_adr@di = -4
-
-P:shr cl,1     ; B@cl = 0..8..31,31..0
-
-  int 10h      ; set video mode / color: bx=index dh=R ch=G cl=B
-
-  movsx cx,bl  ; 0..127,128..255 (palette index)
-  xor ch,cl    ; 0..127,127..0
-  mov cl,ch
-  mov ax,cx
-  mul ax       ; R@dh = 0..16..63,63..16..0
-
-  shr cx,1     ; G@ch = 0..63,63..0
-
-  inc bl       ; keep default color 0
-  js Q         ; R@dh = 0..63,63..16..0
-  xchg cl,dh   ; B@cl = 0..16..63,63..0
-Q:mov ax,1010h
-  jnz P        ;bx=0 cx=0
-
-
-;Each frame: Generate normals to p0..p11=[bp+200h,300h,...].
-M:mov ax,0x4731 ; highest 9 bits: float32 exponent 1/256 (for T)
-                ; lower byte = 2*number of rotations+1
-                ; lowest 4 bits must be 0x1 for 'test cl,al'
-  mov dx,0xA000-10-20-20-4
-  mov es,dx    ; dx:bx = YX:XX = 0x9fca:0
-  pusha  ; adr:   -18 -16 -14 -12 -10  -8  -6  -4  -2
-         ; stack:  di  si  bp  sp  bx  dx  cx  ax   0
-         ; data:   -4 100 9??  -2  0  9fca {T/256}
-  mov cx,12
-G:add bp,si    ; i@cx = 12...1; bp points to p[12-i]; carry=0
-  pusha
-
-;Generate 12 planes with unit normals.
-
-;  fld1         ; platonic dodecahedron: exact is atan((1+sqrt5)/2)=1.017rad
-  fld dword[di-2]    ;|t=T/256: morphing shape: cube, platonic12, rhombic12
-
-  fsincos
-
-  fldz               ;|a=0 b c (a*a+b*b+c*c = 1)
-;  fldlg2 ;irregular shape
-
-N:test cl,al ;=1     ;|a b c
-  jnz K
-  fchs
-K:fstp st3           ;|b c +-a (scramble so that all 12 planes are generated)
-  loop N  ;cl=0      ;|z x y
-
-;Do a bunch of slow rotations. z x y -> cx-sy cy+sx z
-
-R:fstp st3           ;|x y z
-Z:fld st1            ;|y x y z                     ;|x sy x cy z
-  fld dword[di-2]    ;|t=T/256
-  fsincos            ;|c=cos(t) s=sin(t) y x y z   ;|c s x sy x cy z
-  fmulp st4          ;|s y x cy z                  ;|s x sy cx cy z
-  fmulp              ;|sy x cy z                   ;|sx sy cx cy z
-  add al,0x7F ; loop 2x
-BIG equ $-1    ;=28799 (anything higher and you'll get overflow glitches)
-  jo Z
-  faddp st3          ;|sy cx cy+sx z
-  fsubp              ;|new.z=cx-sy .x=cy+sx .y=z
-  jc R       ; loop 24x
-
-S:fstp dword[bp+si] ;[bp+100]=.z [bp+104]=.x [bp+108]=.y
-  sub si,di
-  jpo S
-
-  popa
-  loop G
-C:popa ;=16993, background color multiplier
-
-; the visible pixels are A0000..AF9FF, I want X=0 Y=0 in the center
-;Each pixel: cx=T dx:bx=YX:XX(init=9fca:0) di=adr(init=-4)
-X:inc dx       ; part of "dx:bx += 0x0000CCCD"
-X2:
-  stosb
-
-  pusha        ; adr:     -18 -16 -14 -12 -10  -8  -6  -4  -2
-  fninit       ; stack:    di  si  bp  sp  bx  dx  cx  ax   0
-  mov bx,es    ; s16:  pixadr 100 9??  -2  ..X..Y  T result
-  mov di,-4 ;di = address of pushed ax
-
-;Compute ray direction.
-  fild word[byte BIG+si-100h]  ; store 28799 as a double, read as two floats
-C2 equ $-2 ;=20036, foreground color multiplier
-  fst qword[bx]     ; t_front@float[bx] = 0, t_back@float[bx+4] = 6.879
-  fild word[di+4-9]
-  fild word[di+4-8]  ;|y=Y x=X z=BIG
-
-;Intersect the pyrite.
-  call GEM
-  popa         ; color -> pushed ax
-;  mov al,dl    ; show only palette
-
-;; Faster, but lower quality: draw each pixel twice.
-;  stosb
-;  add bx,0xCCCD; dx:bx = YXX += 0000CCCD
-;  adc dx,0
-
-  add bx,0xCCCD; dx:bx = YXX += 0000CCCD
-  jnc X2
-  jnz X        ; do 65536 pixels
-  
-  in al,60h
-  dec ax  ; ah=0 (checkboard uses positive color indices)
-  loopnz M        ; T--
-;  ret          ; fallthrough
-
-GEM:
-;Hit the pyrite.
-  xchg ax,cx   ; ax = T
-
-; Faster (+4 or +8 bytes): test the shape only in the center of the screen
-  add dh,dh
-  jo B
-  add dl,dl
-  jo B
-
-;Ray-plane intersection.
-;Find the front plane with maximum t and back plane with minimum t.
-; tf@[bx],    tb@[bx+4]      ray parameter t
-; pf@[bx+si], pb@[bx+4+si]   pointer to plane
-  mov cx,12  ; i@cx = 12...1
-I:add bp,si    ; bp points to p[i]
-  fldlg2             ;|pd=0.301 y x z
-  fadd dword[bp+si]  ;|N=pd-(ro'p[i]) y x z  ; ro = 0 0 -1
-
-  push si      ; Dot product:
-D:fld dword[bp+si]   ;|p[i].z ...
-  fmul st4           ;|rd.z*p[i].z ...
-  sub si,di    ; 100 104 108
-  jpo D              ;|(rd*p[i]).y .x .z N rd.y .x .z
-  pop si
-  faddp
-  faddp              ;|D=(rd'p[i]) N y x z
-
-;If we hit the plane from the front (D<0), update tf. Otherwise update tb.
-  push bx
-  fst dword[bp+di]; -> p[i].dot_rd (will be read later)
-  test [bp+di+2],sp ; sf=1 if we're in front of the plane
-  js FRONT
-  sub bx,di    ; bx = address of tf?tb
-FRONT:         ; D<0:  if tf*D < N { tf=N/D; pf=current; }  maximalize tf
-  fld st0      ; D>=0: if tb*D < N { tb=N/D; pb=current; }  minimalize tb
-  fmul dword[bx]     ;|(tf?tb)*D D N y x z
-
-;;DosBOX-compatible FPU comparison, +5 bytes (+3 but we need ax)
-;  push ax
-;  fcomp st2          ;|D N y x z
-;  fnstsw ax
-;  sahf         ; cf = (tf?tb)*D < N
-;  pop ax
-;  jc NEXT
-
-  fcomip st2
-  jc NEXT
-
-;another alternative, +6 bytes
-;  fsub st2
-;  fstp dword[bp-8]
-;  test [bp-6],sp ; sf=1 if <0
-;  js NEXT
-
-
-  fdivr st1          ;|t=N/D N y x z
-  fst dword[bx] ; -> tf?tb
-  mov [bx+si],bp ; pf?pb = current
-NEXT:
-  fcompp
-  pop bx             ;|y x z
-
-  mov dx,[bx+6]
-  cmp dx,[bx+2]  ; if tf>tb { no_hit: early exit }
-  jng B     ;si=100   ;|y x z
-
-  loop I
-
-;Reflect: reflect(i,n) = i - 2*n*(i'n)
-  mov bx,[bx+si] ; pf
-Y:fld dword[bx+di]   ;|(rd'pf) rd.y .x .z  ; reads pf->dot_rd
-  fmul dword[bx+si]  ;|(rd'pf)*pf.z rd.y .x .z
-  fadd st0           ;|2*(rd'pf)*pf.z rd.y .x .z
-  fsubr st3          ;|R.z=rd.z-2*(rd'pf)*pf.z rd.y .x .z
-  sub si,di   ;100 104 108
-  jpo Y     ;si=10C  ;|(R=i-2*n(i'n)).y R.x R.z rd.y .x .z
-
-;Environment map: chessboard below, sky gradient above.
-B:
-; Subtle highlight on the pyrite.
-  fld st0
-  fimul word[byte C+si-100h]  ; 16993 (background) or 20036 (pyrit)
-  fistp dword[di]     ;|y x z
-  sar dword[di],22    ; if y>=-0.5 { chessboard } else { sky }
-  js E             ; the sky is just y (= y^2 after gamma)
-
-; Everything the same brightness. (-6 bytes)
-;  fist word[di]      ;|y x z
-;  sar word[di],8  ; if y>=-0.5 { chessboard } else { sky }
-;  js E            ; the sky is just y (= y^2 after gamma)
-
-; Dark background version.
-;  fist word[di]      ;|y x z
-;  shld cx,si,16-3
-;  xor cl,9        ; hit?8:9 - make the background darker
-;  sar word[di],cl ; if y>=-0.5 { chessboard } else { sky }
-;  js E            ; the sky is just y (= y^2 after gamma)
-
-  fidivr word[si]    ;|C/y x z (C = hit?-30515:-20401)
-  fmul st1,st0
-  fmul st2           ;|u=z*C/y v=x*C/y z
-
-  fistp dword[bp+di]
-  sub al,[bp+di+1]
-  fistp dword[bp+di]
-  xor al,[bp+di+1] ; xortex@ax = (T-u) XOR v
-
-;  aam -32-24     ; more interesting floor texture
-  and al,9<<3
-  add al,10<<3    ; tex = (xortex AND 0b1001) + 10 [10|11|18|19]
-  mul byte[di]
-  mov [di],ah     ; pushed al = tex*y
-
-E:ret
+; Pyrit
+
+; a 256-byte intro by Rrrola <rrrola@gmail.com>
+
+; greets to everyone who's computer is too fast :)
+
+; This is loosely based on my intro 'Gem' (shown on Demobit),
+; but the code is much better.
+
+; Vector3: X right, Y down, Z forward.
+; On the FP stack it looks like {Y X Z} (Y is often used in comparisons).
+; In memory it looks like {Z X Y}, which saves a displacement byte.
+; (u'v) is the dot product: ux*vx + uy*vy + uz*vz.
+
+org 100h ; assume al=0 bx=0 sp=di=-2 si=0100h bp=09??h
+
+;Set video mode and earth+sky palette
+  dec di       ; u16[100h] = -20401, u16[10Ch] = -30515
+  mov al,13h
+  dec di       ; initial pixel_adr@di = -4
+
+P:shr cl,1     ; B@cl = 0..8..31,31..0
+
+  int 10h      ; set video mode / color: bx=index dh=R ch=G cl=B
+
+  movsx cx,bl  ; 0..127,128..255 (palette index)
+  xor ch,cl    ; 0..127,127..0
+  mov cl,ch
+  mov ax,cx
+  mul ax       ; R@dh = 0..16..63,63..16..0
+
+  shr cx,1     ; G@ch = 0..63,63..0
+
+  inc bl       ; keep default color 0
+  js Q         ; R@dh = 0..63,63..16..0
+  xchg cl,dh   ; B@cl = 0..16..63,63..0
+Q:mov ax,1010h
+  jnz P        ;bx=0 cx=0
+
+
+;Each frame: Generate normals to p0..p11=[bp+200h,300h,...].
+M:mov ax,0x4731 ; highest 9 bits: float32 exponent 1/256 (for T)
+                ; lower byte = 2*number of rotations+1
+                ; lowest 4 bits must be 0x1 for 'test cl,al'
+  mov dx,0xA000-10-20-20-4
+  mov es,dx    ; dx:bx = YX:XX = 0x9fca:0
+  pusha  ; adr:   -18 -16 -14 -12 -10  -8  -6  -4  -2
+         ; stack:  di  si  bp  sp  bx  dx  cx  ax   0
+         ; data:   -4 100 9??  -2  0  9fca {T/256}
+  mov cx,12
+G:add bp,si    ; i@cx = 12...1; bp points to p[12-i]; carry=0
+  pusha
+
+;Generate 12 planes with unit normals.
+
+;  fld1         ; platonic dodecahedron: exact is atan((1+sqrt5)/2)=1.017rad
+  fld dword[di-2]    ;|t=T/256: morphing shape: cube, platonic12, rhombic12
+
+  fsincos
+
+  fldz               ;|a=0 b c (a*a+b*b+c*c = 1)
+;  fldlg2 ;irregular shape
+
+N:test cl,al ;=1     ;|a b c
+  jnz K
+  fchs
+K:fstp st3           ;|b c +-a (scramble so that all 12 planes are generated)
+  loop N  ;cl=0      ;|z x y
+
+;Do a bunch of slow rotations. z x y -> cx-sy cy+sx z
+
+R:fstp st3           ;|x y z
+Z:fld st1            ;|y x y z                     ;|x sy x cy z
+  fld dword[di-2]    ;|t=T/256
+  fsincos            ;|c=cos(t) s=sin(t) y x y z   ;|c s x sy x cy z
+  fmulp st4          ;|s y x cy z                  ;|s x sy cx cy z
+  fmulp              ;|sy x cy z                   ;|sx sy cx cy z
+  add al,0x7F ; loop 2x
+BIG equ $-1    ;=28799 (anything higher and you'll get overflow glitches)
+  jo Z
+  faddp st3          ;|sy cx cy+sx z
+  fsubp              ;|new.z=cx-sy .x=cy+sx .y=z
+  jc R       ; loop 24x
+
+S:fstp dword[bp+si] ;[bp+100]=.z [bp+104]=.x [bp+108]=.y
+  sub si,di
+  jpo S
+
+  popa
+  loop G
+C:popa ;=16993, background color multiplier
+
+; the visible pixels are A0000..AF9FF, I want X=0 Y=0 in the center
+;Each pixel: cx=T dx:bx=YX:XX(init=9fca:0) di=adr(init=-4)
+X:inc dx       ; part of "dx:bx += 0x0000CCCD"
+X2:
+  stosb
+
+  pusha        ; adr:     -18 -16 -14 -12 -10  -8  -6  -4  -2
+  fninit       ; stack:    di  si  bp  sp  bx  dx  cx  ax   0
+  mov bx,es    ; s16:  pixadr 100 9??  -2  ..X..Y  T result
+  mov di,-4 ;di = address of pushed ax
+
+;Compute ray direction.
+  fild word[byte BIG+si-100h]  ; store 28799 as a double, read as two floats
+C2 equ $-2 ;=20036, foreground color multiplier
+  fst qword[bx]     ; t_front@float[bx] = 0, t_back@float[bx+4] = 6.879
+  fild word[di+4-9]
+  fild word[di+4-8]  ;|y=Y x=X z=BIG
+
+;Intersect the pyrite.
+  call GEM
+  popa         ; color -> pushed ax
+;  mov al,dl    ; show only palette
+
+;; Faster, but lower quality: draw each pixel twice.
+;  stosb
+;  add bx,0xCCCD; dx:bx = YXX += 0000CCCD
+;  adc dx,0
+
+  add bx,0xCCCD; dx:bx = YXX += 0000CCCD
+  jnc X2
+  jnz X        ; do 65536 pixels
+
+  in al,60h
+  dec ax  ; ah=0 (checkboard uses positive color indices)
+  loopnz M        ; T--
+;  ret          ; fallthrough
+
+GEM:
+;Hit the pyrite.
+  xchg ax,cx   ; ax = T
+
+; Faster (+4 or +8 bytes): test the shape only in the center of the screen
+  add dh,dh
+  jo B
+  add dl,dl
+  jo B
+
+;Ray-plane intersection.
+;Find the front plane with maximum t and back plane with minimum t.
+; tf@[bx],    tb@[bx+4]      ray parameter t
+; pf@[bx+si], pb@[bx+4+si]   pointer to plane
+  mov cx,12  ; i@cx = 12...1
+I:add bp,si    ; bp points to p[i]
+  fldlg2             ;|pd=0.301 y x z
+  fadd dword[bp+si]  ;|N=pd-(ro'p[i]) y x z  ; ro = 0 0 -1
+
+  push si      ; Dot product:
+D:fld dword[bp+si]   ;|p[i].z ...
+  fmul st4           ;|rd.z*p[i].z ...
+  sub si,di    ; 100 104 108
+  jpo D              ;|(rd*p[i]).y .x .z N rd.y .x .z
+  pop si
+  faddp
+  faddp              ;|D=(rd'p[i]) N y x z
+
+;If we hit the plane from the front (D<0), update tf. Otherwise update tb.
+  push bx
+  fst dword[bp+di]; -> p[i].dot_rd (will be read later)
+  test [bp+di+2],sp ; sf=1 if we're in front of the plane
+  js FRONT
+  sub bx,di    ; bx = address of tf?tb
+FRONT:         ; D<0:  if tf*D < N { tf=N/D; pf=current; }  maximalize tf
+  fld st0      ; D>=0: if tb*D < N { tb=N/D; pb=current; }  minimalize tb
+  fmul dword[bx]     ;|(tf?tb)*D D N y x z
+
+;;DosBOX-compatible FPU comparison, +5 bytes (+3 but we need ax)
+;  push ax
+;  fcomp st2          ;|D N y x z
+;  fnstsw ax
+;  sahf         ; cf = (tf?tb)*D < N
+;  pop ax
+;  jc NEXT
+
+  fcomip st2
+  jc NEXT
+
+;another alternative, +6 bytes
+;  fsub st2
+;  fstp dword[bp-8]
+;  test [bp-6],sp ; sf=1 if <0
+;  js NEXT
+
+
+  fdivr st1          ;|t=N/D N y x z
+  fst dword[bx] ; -> tf?tb
+  mov [bx+si],bp ; pf?pb = current
+NEXT:
+  fcompp
+  pop bx             ;|y x z
+
+  mov dx,[bx+6]
+  cmp dx,[bx+2]  ; if tf>tb { no_hit: early exit }
+  jng B     ;si=100   ;|y x z
+
+  loop I
+
+;Reflect: reflect(i,n) = i - 2*n*(i'n)
+  mov bx,[bx+si] ; pf
+Y:fld dword[bx+di]   ;|(rd'pf) rd.y .x .z  ; reads pf->dot_rd
+  fmul dword[bx+si]  ;|(rd'pf)*pf.z rd.y .x .z
+  fadd st0           ;|2*(rd'pf)*pf.z rd.y .x .z
+  fsubr st3          ;|R.z=rd.z-2*(rd'pf)*pf.z rd.y .x .z
+  sub si,di   ;100 104 108
+  jpo Y     ;si=10C  ;|(R=i-2*n(i'n)).y R.x R.z rd.y .x .z
+
+;Environment map: chessboard below, sky gradient above.
+B:
+; Subtle highlight on the pyrite.
+  fld st0
+  fimul word[byte C+si-100h]  ; 16993 (background) or 20036 (pyrit)
+  fistp dword[di]     ;|y x z
+  sar dword[di],22    ; if y>=-0.5 { chessboard } else { sky }
+  js E             ; the sky is just y (= y^2 after gamma)
+
+; Everything the same brightness. (-6 bytes)
+;  fist word[di]      ;|y x z
+;  sar word[di],8  ; if y>=-0.5 { chessboard } else { sky }
+;  js E            ; the sky is just y (= y^2 after gamma)
+
+; Dark background version.
+;  fist word[di]      ;|y x z
+;  shld cx,si,16-3
+;  xor cl,9        ; hit?8:9 - make the background darker
+;  sar word[di],cl ; if y>=-0.5 { chessboard } else { sky }
+;  js E            ; the sky is just y (= y^2 after gamma)
+
+  fidivr word[si]    ;|C/y x z (C = hit?-30515:-20401)
+  fmul st1,st0
+  fmul st2           ;|u=z*C/y v=x*C/y z
+
+  fistp dword[bp+di]
+  sub al,[bp+di+1]
+  fistp dword[bp+di]
+  xor al,[bp+di+1] ; xortex@ax = (T-u) XOR v
+
+;  aam -32-24     ; more interesting floor texture
+  and al,9<<3
+  add al,10<<3    ; tex = (xortex AND 0b1001) + 10 [10|11|18|19]
+  mul byte[di]
+  mov [di],ah     ; pushed al = tex*y
+
+E:ret