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calmanfp.asm
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Assembly Source File
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1994-09-24
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66KB
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1,815 lines
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; calmanfp.asm - floating point version of the calcmand.asm file
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; The following code was adapted from a little program called "Mandelbrot
; Sets by Wesley Loewer" which had a very limited distribution (my
; Algebra II class). It didn't have any of the fancy integer math, but it
; did run floating point stuff pretty fast.
;
; The code was originally optimized for a 287 ('cuz that's what I've got)
; and for a large maxit (ie: use of generous overhead outside the loop to get
; slightly faster code inside the loop), which is generally the case when
; Fractint chooses to use floating point math. This code also has the
; advantage that once the initial parameters are loaded into the fpu
; register, no transfers of fp values to/from memory are needed except to
; check periodicity and to show orbits and the like. Thus, values keep all
; the significant digits of the full 10 byte real number format internal to
; the fpu. Intermediate results are not rounded to the normal IEEE 8 byte
; format (double) at any time.
;
; The non fpu specific stuff, such as periodicity checking and orbits,
; was adapted from CALCFRAC.C and CALCMAND.ASM.
;
; This file must be assembled with floating point emulation turned on. I
; suppose there could be some compiler differences in the emulation
; libraries, but this code has been successfully tested with the MSQC 2.51
; and MSC 5.1 emulation libraries.
;
; Wes Loewer
;
; and now for some REAL fractal calculations...
; (get it, real, floating point..., never mind)
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; 1. Made maxit a dword variable. 1/18/94
; required for compatibility if Turbo ASM
IFDEF ??version
MASM51
QUIRKS
ENDIF
.8086
.8087
.MODEL medium,c
; external functions
EXTRN keypressed:FAR ; this routine is in 'general.asm'
EXTRN getakey:FAR ; this routine is in 'general.asm'
EXTRN plot_orbit:FAR ; this routine is in 'fracsubr.c'
EXTRN scrub_orbit:FAR ; this routine is in 'fracsubr.c'
; external data
EXTRN init:WORD ; declared as type complex
EXTRN parm:WORD ; declared as type complex
EXTRN new:WORD ; declared as type complex
EXTRN maxit:DWORD
EXTRN inside:WORD
EXTRN outside:WORD
EXTRN fpu:WORD ; fpu type: 87, 287, or 387
EXTRN cpu:WORD ; cpu type
EXTRN rqlim:QWORD ; bailout (I never did figure out
; what "rqlim" stands for. -Wes)
EXTRN coloriter:DWORD
EXTRN oldcoloriter:DWORD
EXTRN realcoloriter:DWORD
EXTRN periodicitycheck:WORD
EXTRN reset_periodicity:WORD
EXTRN closenuff:QWORD
EXTRN fractype:WORD ; Mandelbrot or Julia
EXTRN kbdcount:WORD ; keyboard counter
EXTRN dotmode:WORD
EXTRN show_orbit:WORD ; "show-orbit" flag
EXTRN orbit_ptr:WORD ; "orbit pointer" flag
EXTRN potflag:WORD ; potential flag
EXTRN magnitude:QWORD ; when using potential
extrn nextsavedincr:word ; for incrementing AND value
extrn firstsavedand:dword ; AND value
JULIAFP EQU 6 ; from FRACTYPE.H
MANDELFP EQU 4
GREEN EQU 2 ; near y-axis
YELLOW EQU 6 ; near x-axis
KEYPRESSDELAY equ 16383 ; 3FFFh
initx EQU <qword ptr init> ; just to make life easier
inity EQU <qword ptr init+8>
parmx EQU <qword ptr parm>
parmy EQU <qword ptr parm+8>
newx EQU <qword ptr new>
newy EQU <qword ptr new+8>
; Apparently, these might be needed for TC++ overlays. I don't know if
; these are really needed here since I am not familiar with TC++. -Wes
FRAME MACRO regs
push bp
mov bp, sp
IRP reg, <regs>
push reg
ENDM
ENDM
UNFRAME MACRO regs
IRP reg, <regs>
pop reg
ENDM
pop bp
ENDM
.DATA
align 2
savedx DQ ?
savedy DQ ?
orbit_real DQ ?
orbit_imag DQ ?
_2_ DQ 2.0
_4_ DQ 4.0
close DD 0.01
round_down_half DD 0.5
one_8_zero DD 180.0
tmp_word DW ?
tmp_dword DD ?
inside_color DD ?
periodicity_color DW ?
savedand DD ? ; need 4 bytes now, not 2
;savedincr DW ?
;savedand EQU SI ; this doesn't save much time or
savedincr EQU DI ; space, but it doesn't hurt either
.CODE
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; This routine is called once per image.
; Put things here that won't change from one pixel to the next.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
PUBLIC calcmandfpasmstart
calcmandfpasmstart PROC
; not sure if needed here
FRAME <di,si> ; std frame, for TC++ overlays
mov ax,inside
cmp ax,0 ; if (inside color == maxiter)
jnl non_neg_inside
mov ax,word ptr maxit ; use maxit as inside_color
mov dx,word ptr maxit+2 ; use maxit as inside_color
non_neg_inside: ; else
mov word ptr inside_color,ax ; use inside as inside_color
mov word ptr inside_color+2,dx ; use inside as inside_color
cmp periodicitycheck,0 ; if periodicitycheck < 0
jnl non_neg_periodicitycheck
mov ax,7 ; use color 7 (default white)
non_neg_periodicitycheck: ; else
mov periodicity_color,ax ; use inside_color still in ax
mov word ptr oldcoloriter,0 ; no periodicity checking on 1st pixel
mov word ptr oldcoloriter+2,0 ; no periodicity checking on 1st pixel
sub ax,ax ; ax=0
sub dx,dx
UNFRAME <si,di> ; pop stack frame
ret
calcmandfpasmstart ENDP
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; floating point version of calcmandasm
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
PUBLIC calcmandfpasm
calcmandfpasm PROC
FRAME <di,si> ; std frame, for TC++ overlays
; initialization stuff
sub ax,ax ; clear ax
mov dx,ax ; dx=0
cmp periodicitycheck,ax ; periodicity checking?
je initoldcolor ; no, set oldcolor 0 to disable it
cmp inside,-59 ; zmag?
je initoldcolor ; set oldcolor to 0
cmp reset_periodicity,ax ; periodicity reset?
je short initparms ; no, inherit oldcolor from prior invocation
mov ax,word ptr maxit ; yup. reset oldcolor to maxit-250
mov dx,word ptr maxit+2
sub ax,250 ; (avoids slowness at high maxits)
sbb dx,0 ; (faster than conditional jump)
initoldcolor:
mov word ptr oldcoloriter,ax ; reset oldcolor
mov word ptr oldcoloriter+2,dx ; reset oldcolor
initparms:
sub ax,ax ; clear ax
mov dx,ax ; clear dx
mov word ptr savedx,ax ; savedx = 0.0
mov word ptr savedx+2,ax ; needed since savedx is a QWORD
mov word ptr savedx+4,ax
mov word ptr savedx+6,ax
mov word ptr savedy,ax ; savedy = 0.0
mov word ptr savedy+2,ax ; needed since savedy is a QWORD
mov word ptr savedy+4,ax
mov word ptr savedy+6,ax
mov ax,word ptr firstsavedand+2 ; high part of savedand=0
mov word ptr savedand+2,ax ; high part of savedand=0
mov ax,word ptr firstsavedand ; low part of savedand
mov word ptr savedand,ax ; low part of savedand
mov savedincr,1 ; savedincr = 1
mov orbit_ptr,0 ; clear orbits
dec kbdcount ; decrement the keyboard counter
jns short step_nokey ; skip keyboard test if still positive
mov kbdcount,10 ; stuff in a low kbd count
cmp show_orbit,0 ; are we showing orbits?
jne quickkbd ; yup. leave it that way.
;this may need to be adjusted, I'm guessing at the "appropriate" values -Wes
mov kbdcount,5000 ; else, stuff an appropriate count val
cmp fpu,387 ; ("appropriate" to the FPU)
je short kbddiskadj ; ...
mov kbdcount,3000 ; ...
cmp fpu,287 ; ...
je short kbddiskadj ; ...
mov kbdcount,1000 ; ...
cmp fpu,87 ; ...
je short kbddiskadj ; ...
mov kbdcount,500 ; emulation
jmp short kbddiskadj
step_nokey:
jmp nokey
kbddiskadj:
cmp dotmode,11 ; disk video?
jne quickkbd ; no, leave as is
shr kbdcount,1 ; yes, reduce count
shr kbdcount,1 ; yes, reduce count
quickkbd:
call far ptr keypressed ; has a key been pressed?
cmp ax,0 ; ...
je nokey ; nope. proceed
mov kbdcount,0 ; make sure it goes negative again
cmp ax,'o' ; orbit toggle hit?
je orbitkey ; yup. show orbits
cmp ax,'O' ; orbit toggle hit?
jne keyhit ; nope. normal key.
orbitkey:
call far ptr getakey ; read the key for real
mov ax,1 ; reset orbittoggle = 1 - orbittoggle
sub ax,show_orbit ; ...
mov show_orbit,ax ; ...
jmp short nokey ; pretend no key was hit
keyhit:
mov ax,-1 ; return with -1
mov dx,ax
mov word ptr coloriter,ax ; set color to -1
mov word ptr coloriter+2,ax ; set color to -1
UNFRAME <si,di> ; pop stack frame
ret ; bail out!
nokey:
; OK, here's the heart of the floating point code.
; In my original program, the bailout value was loaded once per image and
; was left on the floating point stack after each pixel, and finally popped
; off the stack when the fractal was finished. A lot of overhead for very
; little gain in my opinion, so I changed it so that it loads and unloads
; per pixel. -Wes
fld rqlim ; everything needs bailout first
cmp cpu,386
je check_for_386_387
not_a_386_387:
mov cx,word ptr maxit+2 ; using cx and bx as loop counter
mov bx,word ptr maxit ; using cx and bx as loop counter
cmp fpu,387 ; jump to fpu specific code
je start_387 ; 387, slight efficiency tweeking
cmp fpu,287 ;
je to_start_287 ; 287 (original version)
jmp start_87 ; else must be 87/emulation
to_start_287:
jmp start_287 ; needs a long jump here
check_for_386_387:
cmp fpu,387
jb not_a_386_387
.386
mov ecx,maxit
.8086
jmp start_386_387
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; _387 code is just like _287 code except that it uses an FADD instead
; of an FSCALE per orbit and also saves an FLD1 per pixel.
;
; You could use .386/.387 here, but it is not necessary. The _387 floating
; point routines in this file do not have any 387 specific op-codes,
; only 387 specific optimizations. (And plus my MS QuickAssembler does not
; recognize the .386/.387 directives.) -Wes
;
.286
.287
start_387:
cmp fractype,JULIAFP ; julia or mandelbrot set?
je short dojulia_387 ; julia set - go there
; Mandelbrot _387 initialization of stack
sub bx,1 ; always requires at least 1 iteration
sbb cx,0
; the fpu stack is shown below
; st(0) ... st(7)
; b (already on stack)
fld inity ; Cy b
fld initx ; Cx Cy b
fld st(1) ; Cy Cx Cy b
fadd parmy ; Py+Cy Cx Cy b
fld st ; Py+Cy Py+Cy Cx Cy b
fmul st,st ; (Py+Cy)^2 Py+Cy Cx Cy b
fld st(2) ; Cx (Py+Cy)^2 Py+Cy Cx Cy b
fadd parmx ; Px+Cx (Py+Cy)^2 Py+Cy Cx Cy b
fmul st(2),st ; Px+Cx (Py+Cy)^2 (Py+Cy)(Px+Cx) Cx Cy b
fmul st,st ; (Px+Cx)^2 (Py+Cy)^2 (Py+Cy)(Px+Cx) Cx Cy b
; which is the next x^2 y^2 xy Cx Cy b
jmp short top_of_cx_loop_387 ; branch around the julia switch
dojulia_387:
; Julia 387 initialization of stack
; note that init and parm are "reversed"
; b (already on stack)
fld parmy ; Cy b
fld parmx ; Cx Cy b
fld inity ; y Cx Cy b
fld st ; y y Cx Cy b
fmul st,st ; y^2 y Cx Cy b
fld initx ; x y^2 y Cx Cy b
fmul st(2),st ; x y^2 xy Cx Cy b
fmul st,st ; x^2 y^2 xy Cx Cy b
top_of_cx_loop_387: ; x^2 y^2 xy Cx Cy b
fsubr ; x^2-y^2 xy Cx Cy b
fadd st,st(2) ; x^2-y^2+Cx xy Cx Cy b
fxch ; xy x^2-y^2+Cx Cx Cy b
; FADD is faster than FSCALE for 387
fadd st,st ; 2xy x^2-y^2+Cx Cx Cy b
fadd st,st(3) ; 2xy+Cy x^2-y^2+Cx Cx Cy b
; now same as the new
; y x Cx Cy b
cmp outside,-2 ; real, imag, mult, or sum ?
jg no_save_new_xy_387 ; if not, then skip this
fld st(1) ; x y x Cx Cy b
fstp newx ; y x Cx Cy b
fst newy ; y x Cx Cy b
no_save_new_xy_387:
cmp inside,-100 ; epsilon cross ?
jne end_epsilon_cross_387
call near ptr epsilon_cross ; y x Cx Cy b
cmp bx,0
jnz end_epsilon_cross_387
cmp cx,0
jnz end_epsilon_cross_387 ; if cx=0, pop stack
jmp pop_stack_387
end_epsilon_cross_387:
test bx,KEYPRESSDELAY ; bx holds the low word of the loop count
jne notakey1 ; don't test yet
push cx
push bx
call far ptr keypressed ; has a key been pressed?
pop bx
pop cx
cmp ax,0 ; ...
je notakey1 ; nope. proceed
jmp keyhit
notakey1:
cmp cx,word ptr oldcoloriter+2 ; if cx > oldcoloriter
ja end_periodicity_check_387 ; don't check periodicity
cmp bx,word ptr oldcoloriter ; if bx >= oldcoloriter
jae end_periodicity_check_387 ; don't check periodicity
call near ptr periodicity_check_287_387 ; y x Cx Cy b
cmp bx,0
jnz end_periodicity_check_387
cmp cx,0
jnz end_periodicity_check_387 ; if cx=0, pop stack
jmp pop_stack_387
end_periodicity_check_387:
cmp show_orbit,0 ; is show_orbit clear
je no_show_orbit_387 ; if so then skip
call near ptr show_orbit_xy ; y x Cx Cy b
no_show_orbit_387:
; y x Cx Cy b
fld st(1) ; x y x Cx Cy b
fld st(1) ; y x y x Cx Cy b
fmul st(3),st ; y x y xy Cx Cy b
fmulp st(2),st ; x y^2 xy Cx Cy b
fmul st,st ; x^2 y^2 xy Cx Cy b
fld st ; x^2 x^2 y^2 xy Cx Cy b
fadd st,st(2) ; x^2+y^2 x^2 y^2 xy Cx Cy b
cmp potflag,0 ; check for potential
je no_potflag_387
fst magnitude ; if so, save magnitude
no_potflag_387:
fcomp st(6) ; x^2 y^2 xy Cx Cy b
fstsw ax
sahf
ja over_bailout_387
;less than or equal to bailout
; loop top_of_cx_loop_387 ; x^2 y^2 xy Cx Cy b
sub bx,1
sbb cx,0
jnz top_of_cx_loop_387
cmp bx,0
jnz top_of_cx_loop_387
; reached maxit, inside
mov word ptr oldcoloriter,-1 ; check periodicity immediately next time
mov word ptr oldcoloriter+2,-1 ; check periodicity immediately next time
mov ax,word ptr maxit
mov dx,word ptr maxit+2
sub kbdcount,ax ; adjust the keyboard count
mov word ptr realcoloriter,ax ; save unadjusted realcoloriter
mov word ptr realcoloriter+2,dx ; save unadjusted realcoloriter
mov ax,word ptr inside_color
mov dx,word ptr inside_color+2
cmp inside,-59 ; zmag ?
jne no_zmag_387
fadd st,st(1) ; x^2+y^2 y^2 xy Cx Cy b
fimul maxit ; maxit*|z^2| x^2 y^2 xy Cx Cy b
; When type casting floating point variables to integers in C, the decimal
; is truncated. When using FIST in asm, the value is rounded. The following
; line cause the positive value to be truncated.
fsub round_down_half
fist tmp_dword ; tmp_word = |z^2|*maxit
fwait
mov ax,word ptr tmp_dword
mov dx,word ptr tmp_dword+2
shr dx,1 ; |z^2|*maxit/2
rcr ax,1
add ax,1 ; |z^2|*maxit/2+1
adc dx,0
no_zmag_387:
pop_stack_387:
fninit
mov word ptr coloriter,ax
mov word ptr coloriter+2,dx
cmp orbit_ptr,0 ; any orbits to clear?
je calcmandfpasm_ret_387 ; nope.
call far ptr scrub_orbit ; clear out any old orbits
mov ax,word ptr coloriter ; restore color
mov dx,word ptr coloriter+2 ; restore color
; speed not critical here in orbit land
calcmandfpasm_ret_387:
UNFRAME <si,di> ; pop stack frame
fwait ; just to make sure
ret
over_bailout_387: ; x^2 y^2 xy Cx Cy b
; outside
mov dx,cx
mov ax,bx
sub ax,10 ; 10 more next time before checking
sbb dx,0
jns no_fix_underflow_387
; if the number of iterations was within 10 of maxit, then subtracting
; 10 would underflow and cause periodicity checking to start right
; away. Catching a period doesn't occur as often in the pixels at
; the edge of the set anyway.
sub ax,ax ; don't check next time
mov dx,ax
no_fix_underflow_387:
mov word ptr oldcoloriter,ax ; check when past this - 10 next time
mov word ptr oldcoloriter+2,dx ; check when past this - 10 next time
mov ax,word ptr maxit
mov dx,word ptr maxit+2
sub ax,bx ; leave 'times through loop' in ax
sbb dx,cx ; and dx
; zero color fix
jnz zero_color_fix_387
cmp ax,0
jnz zero_color_fix_387
inc ax ; if (ax == 0 ) ax = 1
zero_color_fix_387:
mov word ptr realcoloriter,ax ; save unadjusted realcolor
mov word ptr realcoloriter+2,dx ; save unadjusted realcolor
sub kbdcount,ax ; adjust the keyboard count
cmp outside,-1 ; iter ? (most common case)
je pop_stack_387
cmp outside,-2 ; outside <= -2 ?
jle special_outside_387 ; yes, go do special outside options
mov ax,outside ; use outside color
sub dx,dx
jmp short pop_stack_387
special_outside_387:
call near ptr special_outside
jmp short pop_stack_387
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; _386_387 code is just like _287 code except that it uses an FADD
; instead of an FSCALE per orbit and also saves an FLD1 per pixel.
; And uses 386 specific speedups.
;
.386
.387
start_386_387:
cmp fractype,JULIAFP ; julia or mandelbrot set?
je short dojulia_386_387 ; julia set - go there
; Mandelbrot _386_387 initialization of stack
dec ecx ; always requires at least 1 iteration
; the fpu stack is shown below
; st(0) ... st(7)
; b (already on stack)
fld inity ; Cy b
fld initx ; Cx Cy b
fld st(1) ; Cy Cx Cy b
fadd parmy ; Py+Cy Cx Cy b
fld st ; Py+Cy Py+Cy Cx Cy b
fmul st,st ; (Py+Cy)^2 Py+Cy Cx Cy b
fld st(2) ; Cx (Py+Cy)^2 Py+Cy Cx Cy b
fadd parmx ; Px+Cx (Py+Cy)^2 Py+Cy Cx Cy b
fmul st(2),st ; Px+Cx (Py+Cy)^2 (Py+Cy)(Px+Cx) Cx Cy b
fmul st,st ; (Px+Cx)^2 (Py+Cy)^2 (Py+Cy)(Px+Cx) Cx Cy b
; which is the next x^2 y^2 xy Cx Cy b
jmp short top_of_cx_loop_386_387 ; branch around the julia switch
dojulia_386_387:
; Julia 387 initialization of stack
; note that init and parm are "reversed"
; b (already on stack)
fld parmy ; Cy b
fld parmx ; Cx Cy b
fld inity ; y Cx Cy b
fld st ; y y Cx Cy b
fmul st,st ; y^2 y Cx Cy b
fld initx ; x y^2 y Cx Cy b
fmul st(2),st ; x y^2 xy Cx Cy b
fmul st,st ; x^2 y^2 xy Cx Cy b
top_of_cx_loop_386_387: ; x^2 y^2 xy Cx Cy b
fsubr ; x^2-y^2 xy Cx Cy b
fadd st,st(2) ; x^2-y^2+Cx xy Cx Cy b
fxch ; xy x^2-y^2+Cx Cx Cy b
; FADD is faster than FSCALE for 387
fadd st,st ; 2xy x^2-y^2+Cx Cx Cy b
fadd st,st(3) ; 2xy+Cy x^2-y^2+Cx Cx Cy b
; now same as the new
; y x Cx Cy b
cmp outside,-2 ; real, imag, mult, or sum ?
jg no_save_new_xy_386_387 ; if not, then skip this
fld st(1) ; x y x Cx Cy b
fstp newx ; y x Cx Cy b
fst newy ; y x Cx Cy b
no_save_new_xy_386_387:
cmp inside,-100 ; epsilon cross ?
jne end_epsilon_cross_386_387
call near ptr epsilon_cross_386_387 ; y x Cx Cy b
jecxz step_to_pop_stack_386_387 ; if ecx=0, pop stack
end_epsilon_cross_386_387:
test ecx,KEYPRESSDELAY ; ecx holds the loop count
jne notakey2 ; don't test yet
push ecx
call far ptr keypressed ; has a key been pressed?
pop ecx
cmp ax,0 ; ...
je notakey2 ; nope. proceed
jmp keyhit
notakey2:
cmp ecx,oldcoloriter ; if ecx > oldcolor
jae end_periodicity_check_386_387 ; don't check periodicity
call near ptr periodicity_check_386_387 ; y x Cx Cy b
jecxz step_to_pop_stack_386_387 ; if ecx=0, pop stack
jmp short end_periodicity_check_386_387
step_to_pop_stack_386_387:
jmp short pop_stack_386_387
end_periodicity_check_386_387:
cmp show_orbit,0 ; is show_orbit clear
je no_show_orbit_386_387 ; if so then skip
call near ptr show_orbit_xy ; y x Cx Cy b
no_show_orbit_386_387:
; y x Cx Cy b
fld st(1) ; x y x Cx Cy b
fld st(1) ; y x y x Cx Cy b
fmul st(3),st ; y x y xy Cx Cy b
fmulp st(2),st ; x y^2 xy Cx Cy b
fmul st,st ; x^2 y^2 xy Cx Cy b
fld st ; x^2 x^2 y^2 xy Cx Cy b
fadd st,st(2) ; x^2+y^2 x^2 y^2 xy Cx Cy b
cmp potflag,0 ; check for potential
je no_potflag_386_387
fst magnitude ; if so, save magnitude
no_potflag_386_387:
fcomp st(6) ; x^2 y^2 xy Cx Cy b
fstsw ax
sahf
ja over_bailout_386_387
;less than or equal to bailout
; loopd top_of_cx_loop_386_387 ; x^2 y^2 xy Cx Cy b
dec ecx
jnz top_of_cx_loop_386_387
; reached maxit, inside
mov oldcoloriter,-1 ; check periodicity immediately next time
mov eax,maxit
sub kbdcount,ax ; adjust the keyboard count
mov realcoloriter,eax ; save unadjusted realcolor
mov eax,inside_color
cmp inside,-59 ; zmag ?
jne no_zmag_386_387
fadd st,st(1) ; x^2+y^2 y^2 xy Cx Cy b
fimul maxit ; maxit*|z^2| x^2 y^2 xy Cx Cy b
; When type casting floating point variables to integers in C, the decimal
; is truncated. When using FIST in asm, the value is rounded. The following
; line cause the positive value to be truncated.
fsub round_down_half
fist tmp_dword ; tmp_dword = |z^2|*maxit
fwait
mov eax,tmp_dword
shr eax,1 ; |z^2|*maxit/2
inc eax ; |z^2|*maxit/2+1
no_zmag_386_387:
pop_stack_386_387:
fninit
mov coloriter,eax
cmp orbit_ptr,0 ; any orbits to clear?
je calcmandfpasm_ret_386_387 ; nope.
call far ptr scrub_orbit ; clear out any old orbits
mov eax,coloriter ; restore color
; speed not critical here in orbit land
calcmandfpasm_ret_386_387:
shld edx,eax,16 ; put results in ax,dx
shr eax,16
UNFRAME <si,di> ; pop stack frame
fwait ; just to make sure
ret
over_bailout_386_387: ; x^2 y^2 xy Cx Cy b
; outside
mov eax,ecx
sub eax,10 ; 10 more next time before checking
jns no_fix_underflow_386_387
; if the number of iterations was within 10 of maxit, then subtracting
; 10 would underflow and cause periodicity checking to start right
; away. Catching a period doesn't occur as often in the pixels at
; the edge of the set anyway.
sub eax,eax ; don't check next time
no_fix_underflow_386_387:
mov oldcoloriter,eax ; check when past this - 10 next time
mov eax,maxit
sub eax,ecx ; leave 'times through loop' in eax
; zero color fix
jnz zero_color_fix_386_387
inc eax ; if (eax == 0 ) eax = 1
zero_color_fix_386_387:
mov realcoloriter,eax ; save unadjusted realcolor
sub kbdcount,ax ; adjust the keyboard count
cmp outside,-1 ; iter ? (most common case)
je pop_stack_386_387
cmp outside,-2 ; outside <= -2 ?
jle to_special_outside_386_387 ; yes, go do special outside options
sub eax,eax ; clear top half of eax for next
mov ax,outside ; use outside color
jmp short pop_stack_386_387
to_special_outside_386_387:
call near ptr special_outside_386_387
jmp short pop_stack_386_387
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; _287 version (closely resembles original code)
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.286
.287
start_287: ; 287
cmp fractype,JULIAFP ; julia or mandelbrot set?
je short dojulia_287 ; julia set - go there
; Mandelbrot _287 initialization of stack
sub bx,1 ; always requires at least 1 iteration
sbb cx,0
; the fpu stack is shown below
; st(0) ... st(7)
; b (already on stack)
fld inity ; Cy b
fld initx ; Cx Cy b
fld st(1) ; Cy Cx Cy b
fadd parmy ; Py+Cy Cx Cy b
fld1 ; 1 Py+Cy Cx Cy b
fld st(1) ; Py+Cy 1 Py+Cy Cx Cy b
fmul st,st ; (Py+Cy)^2 1 Py+Cy Cx Cy b
fld st(3) ; Cx (Py+Cy)^2 1 Py+Cy Cx Cy b
fadd parmx ; Px+Cx (Py+Cy)^2 1 Py+Cy Cx Cy b
fmul st(3),st ; Px+Cx (Py+Cy)^2 1 (Py+Cy)(Px+Cx) Cx Cy b
fmul st,st ; (Px+Cx)^2 (Py+Cy)^2 1 (Py+Cy)(Px+Cx) Cx Cy b
; which is the next x^2 y^2 1 xy Cx Cy b
jmp short top_of_cx_loop_287 ; branch around the julia switch
dojulia_287:
; Julia 287 initialization of stack
; note that init and parm are "reversed"
; b (already on stack)
fld parmy ; Cy b
fld parmx ; Cx Cy b
fld inity ; y Cx Cy b
fld1 ; 1 y Cx Cy b
fld st(1) ; y 1 y Cx Cy b
fmul st,st ; y^2 1 y Cx Cy b
fld initx ; x y^2 1 y Cx Cy b
fmul st(3),st ; x y^2 1 xy Cx Cy b
fmul st,st ; x^2 y^2 1 xy Cx Cy b
top_of_cx_loop_287: ; x^2 y^2 1 xy Cx Cy b
fsubr ; x^2-y^2 1 xy Cx Cy b
fadd st,st(3) ; x^2-y^2+Cx 1 xy Cx Cy b
fxch st(2) ; xy 1 x^2-y^2+Cx Cx Cy b
; FSCALE is faster than FADD for 287
fscale ; 2xy 1 x^2-y^2+Cx Cx Cy b
fadd st,st(4) ; 2xy+Cy 1 x^2-y^2+Cx Cx Cy b
; now same as the new
; y 1 x Cx Cy b
cmp outside,-2 ; real, imag, mult, or sum ?
jg no_save_new_xy_287 ; if not, then skip this
fld st(2) ; x y 1 x Cx Cy b
fstp newx ; y 1 x Cx Cy b
fst newy ; y 1 x Cx Cy b
no_save_new_xy_287:
cmp inside,-100 ; epsilon cross ?
jne end_epsilon_cross_287
call near ptr epsilon_cross ; y 1 x Cx Cy b
cmp bx,0
jnz end_epsilon_cross_287
cmp cx,0
jnz end_epsilon_cross_287 ; if cx=0, pop stack
jmp pop_stack_287
end_epsilon_cross_287:
test bx,KEYPRESSDELAY ; bx holds the low word of the loop count
jne notakey3 ; don't test yet
push cx
push bx
call far ptr keypressed ; has a key been pressed?
pop bx
pop cx
cmp ax,0 ; ...
je notakey3 ; nope. proceed
jmp keyhit
notakey3:
cmp cx,word ptr oldcoloriter+2 ; if cx > oldcolor
ja end_periodicity_check_287 ; don't check periodicity
cmp bx,word ptr oldcoloriter ; if bx >= oldcolor
jae end_periodicity_check_287 ; don't check periodicity
call near ptr periodicity_check_287_387 ; y 1 x Cx Cy b
cmp bx,0
jnz end_periodicity_check_287
cmp cx,0
jnz end_periodicity_check_287 ; if cx=0, pop stack
jmp pop_stack_287
end_periodicity_check_287:
cmp show_orbit,0 ; is show_orbit clear
je no_show_orbit_287 ; if so then skip
call near ptr show_orbit_xy ; y 1 x Cx Cy b
no_show_orbit_287:
; y 1 x Cx Cy b
fld st(2) ; x y 1 x Cx Cy b
fld st(1) ; y x y 1 x Cx Cy b
fmul st(4),st ; y x y 1 xy Cx Cy b
fmulp st(2),st ; x y^2 1 xy Cx Cy b
fmul st,st ; x^2 y^2 1 xy Cx Cy b
fld st ; x^2 x^2 y^2 1 xy Cx Cy b
fadd st,st(2) ; x^2+y^2 x^2 y^2 1 xy Cx Cy b
cmp potflag,0 ; check for potential
je no_potflag_287
fst magnitude ; if so, save magnitude
no_potflag_287:
fcomp st(7) ; x^2 y^2 1 xy Cx Cy b
fstsw ax
sahf
ja over_bailout_287
;less than or equal to bailout
; loop top_of_cx_loop_287 ; x^2 y^2 1 xy Cx Cy b
sub bx,1
sbb cx,0
jnz top_of_cx_loop_287
cmp bx,0
jnz top_of_cx_loop_287
; reached maxit, inside
mov word ptr oldcoloriter,-1 ; check periodicity immediately next time
mov word ptr oldcoloriter+2,-1 ; check periodicity immediately next time
mov ax,word ptr maxit
mov dx,word ptr maxit+2
sub kbdcount,ax ; adjust the keyboard count
mov word ptr realcoloriter,ax ; save unadjusted realcolor
mov word ptr realcoloriter+2,dx ; save unadjusted realcolor
mov ax,word ptr inside_color
mov dx,word ptr inside_color+2
cmp inside,-59 ; zmag ?
jne no_zmag_287
fadd st,st(1) ; x^2+y^2 y^2 1 xy Cx Cy b
fimul maxit ; maxit*|z^2| x^2 y^2 1 xy Cx Cy b
; When type casting floating point variables to integers in C, the decimal
; is truncated. When using FIST in asm, the value is rounded. The following
; line cause the positive value to be truncated.
fsub round_down_half
fist tmp_dword ; tmp_word = |z^2|*maxit
fwait
mov ax,word ptr tmp_dword
shr dx,1 ; |z^2|*maxit/2
rcr ax,1
add ax,1 ; |z^2|*maxit/2+1
adc dx,0
no_zmag_287:
pop_stack_287:
fninit
mov word ptr coloriter,ax
mov word ptr coloriter+2,dx
cmp orbit_ptr,0 ; any orbits to clear?
je calcmandfpasm_ret_287 ; nope.
call far ptr scrub_orbit ; clear out any old orbits
mov ax,word ptr coloriter ; restore color
mov dx,word ptr coloriter+2 ; restore color
; speed not critical here in orbit land
calcmandfpasm_ret_287:
UNFRAME <si,di> ; pop stack frame
fwait ; just to make sure
ret
over_bailout_287: ; x^2 y^2 1 xy Cx Cy b
; outside
mov dx,cx
mov ax,bx
sub ax,10 ; 10 more next time before checking
sbb dx,0
jns no_fix_underflow_287
; if the number of iterations was within 10 of maxit, then subtracting
; 10 would underflow and cause periodicity checking to start right
; away. Catching a period doesn't occur as often in the pixels at
; the edge of the set anyway.
sub ax,ax ; don't check next time
mov dx,ax
no_fix_underflow_287:
mov word ptr oldcoloriter,ax ; check when past this - 10 next time
mov word ptr oldcoloriter+2,dx ; check when past this - 10 next time
mov ax,word ptr maxit
mov dx,word ptr maxit+2
sub ax,bx ; leave 'times through loop' in ax
sbb dx,cx ; and dx
; zero color fix
jnz zero_color_fix_287
cmp ax,0
jnz zero_color_fix_287
inc ax ; if (ax == 0 ) ax = 1
zero_color_fix_287:
mov word ptr realcoloriter,ax ; save unadjusted realcolor
mov word ptr realcoloriter+2,dx ; save unadjusted realcolor
sub kbdcount,ax ; adjust the keyboard count
cmp outside,-1 ; iter ? (most common case)
je pop_stack_287
cmp outside,-2 ; outside <= -2 ?
jle special_outside_287 ; yes, go do special outside options
mov ax,outside ; use outside color
sub dx,dx
jmp short pop_stack_287
special_outside_287:
call near ptr special_outside
jmp short pop_stack_287
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; _87 code is just like 287 code except that it must use
; fstsw tmp_word
; fwait
; mov ax,tmp_word
; instead of
; fstsw ax
;
.8086
.8087
start_87:
; let emulation fall through to the 87 code here
; as it seems not emulate correctly on an 8088/86 otherwise
cmp fractype,JULIAFP ; julia or mandelbrot set?
je short dojulia_87 ; julia set - go there
; Mandelbrot _87 initialization of stack
sub bx,1 ; always requires at least 1 iteration
sbb cx,0
; the fpu stack is shown below
; st(0) ... st(7)
; b (already on stack)
fld inity ; Cy b
fld initx ; Cx Cy b
fld st(1) ; Cy Cx Cy b
fadd parmy ; Py+Cy Cx Cy b
fld1 ; 1 Py+Cy Cx Cy b
fld st(1) ; Py+Cy 1 Py+Cy Cx Cy b
fmul st,st ; (Py+Cy)^2 1 Py+Cy Cx Cy b
fld st(3) ; Cx (Py+Cy)^2 1 Py+Cy Cx Cy b
fadd parmx ; Px+Cx (Py+Cy)^2 1 Py+Cy Cx Cy b
fmul st(3),st ; Px+Cx (Py+Cy)^2 1 (Py+Cy)(Px+Cx) Cx Cy b
fmul st,st ; (Px+Cx)^2 (Py+Cy)^2 1 (Py+Cy)(Px+Cx) Cx Cy b
; which is the next x^2 y^2 1 xy Cx Cy b
jmp short top_of_cx_loop_87 ; branch around the julia switch
dojulia_87:
; Julia 87 initialization of stack
; note that init and parm are "reversed"
; b (already on stack)
fld parmy ; Cy b
fld parmx ; Cx Cy b
fld inity ; y Cx Cy b
fld1 ; 1 y Cx Cy b
fld st(1) ; y 1 y Cx Cy b
fmul st,st ; y^2 1 y Cx Cy b
fld initx ; x y^2 1 y Cx Cy b
fmul st(3),st ; x y^2 1 xy Cx Cy b
fmul st,st ; x^2 y^2 1 xy Cx Cy b
top_of_cx_loop_87: ; x^2 y^2 1 xy Cx Cy b
fsubr ; x^2-y^2 1 xy Cx Cy b
fadd st,st(3) ; x^2-y^2+Cx 1 xy Cx Cy b
fxch st(2) ; xy 1 x^2-y^2+Cx Cx Cy b
; FSCALE is faster than FADD for 87
fscale ; 2xy 1 x^2-y^2+Cx Cx Cy b
fadd st,st(4) ; 2xy+Cy 1 x^2-y^2+Cx Cx Cy b
; now same as the new
; y 1 x Cx Cy b
cmp outside,-2 ; real, imag, mult, or sum ?
jg no_save_new_xy_87 ; if not, then skip this
fld st(2) ; x y 1 x Cx Cy b
fstp newx ; y 1 x Cx Cy b
fst newy ; y 1 x Cx Cy b
no_save_new_xy_87:
cmp inside,-100 ; epsilon cross ?
jne end_epsilon_cross_87
call near ptr epsilon_cross ; y 1 x Cx Cy b
cmp bx,0
jnz end_epsilon_cross_87
cmp cx,0
jnz end_epsilon_cross_87 ; if cx=0, pop stack
jmp pop_stack_6_87 ; with a long jump
end_epsilon_cross_87:
test bx,KEYPRESSDELAY ; bx holds the low word of the loop count
jne notakey4 ; don't test yet
push cx
push bx
call far ptr keypressed ; has a key been pressed?
pop bx
pop cx
cmp ax,0 ; ...
je notakey4 ; nope. proceed
jmp keyhit
notakey4:
cmp cx,word ptr oldcoloriter+2 ; if cx > oldcolor
ja no_periodicity_check_87 ; don't check periodicity
cmp bx,word ptr oldcoloriter ; if bx >= oldcolor
jae no_periodicity_check_87 ; don't check periodicity
call near ptr periodicity_check_87 ; y 1 x Cx Cy b
cmp bx,0
jnz no_periodicity_check_87
cmp cx,0
jnz no_periodicity_check_87 ; if cx=0, pop stack
jmp pop_stack_6_87
no_periodicity_check_87:
cmp show_orbit,0 ; is show_orbit clear
je no_show_orbit_87 ; if so then skip
call near ptr show_orbit_xy ; y 1 x Cx Cy b
no_show_orbit_87:
; y 1 x Cx Cy b
fld st(2) ; x y 1 x Cx Cy b
fld st(1) ; y x y 1 x Cx Cy b
fmul st(4),st ; y x y 1 xy Cx Cy b
fmulp st(2),st ; x y^2 1 xy Cx Cy b
fmul st,st ; x^2 y^2 1 xy Cx Cy b
fld st ; x^2 x^2 y^2 1 xy Cx Cy b
fadd st,st(2) ; x^2+y^2 x^2 y^2 1 xy Cx Cy b
cmp potflag,0 ; check for potential
je no_potflag_87
fst magnitude ; if so, save magnitude
no_potflag_87:
fcomp st(7) ; x^2 y^2 1 xy Cx Cy b
fstsw tmp_word
fwait
mov ax,tmp_word
sahf
ja over_bailout_87
;less than or equal to bailout
; loop top_of_cx_loop_87 ; x^2 y^2 1 xy Cx Cy b
sub bx,1
sbb cx,0
jnz top_of_cx_loop_87
cmp bx,0
jnz top_of_cx_loop_87
; reached maxit
mov word ptr oldcoloriter,-1 ; check periodicity immediately next time
mov word ptr oldcoloriter+2,-1 ; check periodicity immediately next time
mov ax,word ptr maxit
mov dx,word ptr maxit+2
sub kbdcount,ax ; adjust the keyboard count
mov word ptr realcoloriter,ax ; save unadjusted realcolor
mov word ptr realcoloriter+2,dx ; save unadjusted realcolor
mov ax,word ptr inside_color
mov dx,word ptr inside_color+2
cmp inside,-59 ; zmag ?
jne no_zmag_87
fadd st,st(1) ; x^2+y^2 y^2 1 xy Cx Cy b
fimul maxit ; maxit*|z^2| x^2 y^2 1 xy Cx Cy b
; When type casting floating point variables to integers in C, the decimal
; is truncated. When using FIST in asm, the value is rounded. The following
; line cause the positive value to be truncated.
fsub round_down_half
fist tmp_dword ; tmp_word = |z^2|*maxit
fwait
mov ax,word ptr tmp_dword
mov dx,word ptr tmp_dword+2
shr dx,1 ; |z^2|*maxit/2
rcr ax,1
add ax,1 ; |z^2|*maxit/2+1
adc dx,0
no_zmag_87:
pop_stack_7_87:
; The idea here is just to clear the floating point stack. There was a
; problem using FNINIT with the emulation library. It didn't seem to
; properly clear the emulated stack, resulting in "stack overflow"
; messages. Therefore, if emulation is being used, then FSTP's are used
; instead.
cmp fpu,0 ; are we using emulation?
jne no_emulation ; if not, then jump
fstp st
; you could just jump over this next check, but its faster to just check again
pop_stack_6_87:
cmp fpu,0 ; are we using emulation?
jne no_emulation ; if not, then jump
fstp st
fstp st
fstp st
fstp st
fstp st
fstp st
jmp short end_pop_stack_87
no_emulation: ; if no emulation, then
fninit ; use the faster FNINIT
end_pop_stack_87:
mov word ptr coloriter,ax
mov word ptr coloriter+2,dx
cmp orbit_ptr,0 ; any orbits to clear?
je calcmandfpasm_ret_87 ; nope.
call far ptr scrub_orbit ; clear out any old orbits
mov ax,word ptr coloriter ; restore color
mov dx,word ptr coloriter+2 ; restore color
; speed not critical here in orbit land
calcmandfpasm_ret_87:
UNFRAME <si,di> ; pop stack frame
fwait ; just to make sure
ret
over_bailout_87: ; x^2 y^2 1 xy Cx Cy b
; outside
mov dx,cx
mov ax,bx
sub ax,10 ; 10 more next time before checking
sbb dx,0
jns no_fix_underflow_87
; if the number of iterations was within 10 of maxit, then subtracting
; 10 would underflow and cause periodicity checking to start right
; away. Catching a period doesn't occur as often in the pixels at
; the edge of the set anyway.
sub ax,ax ; don't check next time
mov dx,ax
no_fix_underflow_87:
mov word ptr oldcoloriter,ax ; check when past this - 10 next time
mov word ptr oldcoloriter+2,dx ; check when past this - 10 next time
mov ax,word ptr maxit
mov dx,word ptr maxit+2
sub ax,bx ; leave 'times through loop' in ax
sbb dx,cx ; and dx
; zero color fix
jnz zero_color_fix_87
cmp ax,0
jnz zero_color_fix_87
inc ax ; if (ax == 0 ) ax = 1
zero_color_fix_87:
mov word ptr realcoloriter,ax ; save unadjusted realcolor
mov word ptr realcoloriter+2,dx ; save unadjusted realcolor
sub kbdcount,ax ; adjust the keyboard count
cmp outside,-1 ; iter ? (most common case)
je pop_stack_7_87
cmp outside,-2 ; outside <= -2 ?
jle special_outside_87 ; yes, go do special outside options
mov ax,outside ; use outside color
sub dx,dx
jmp pop_stack_7_87
special_outside_87:
call near ptr special_outside
jmp pop_stack_7_87
calcmandfpasm ENDP
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Since periodicity checking is used most of the time, I decided to
; separate the periodicity_check routines into a _287_387 version
; and an _87 version to achieve a slight increase in speed. The
; epsilon_cross, show_orbit_xy, and special_outside routines are less
; frequently used and therefore have been implemented as single routines
; usable by the 8087 and up. -Wes
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.286
.287
periodicity_check_287_387 PROC NEAR
; REMEMBER, the cx counter is counting BACKWARDS from maxit to 0
; fpu stack is either
; y x Cx Cy b (387)
; y 1 x Cx Cy b (287/emul)
cmp fpu,387
jb pc_load_x
fld st(1) ; if 387
jmp short pc_end_load_x
pc_load_x:
fld st(2) ; if 287/emul
pc_end_load_x:
; x y ...
test cx,word ptr savedand+2 ; save on 0, check on anything else
jnz do_check_287_387 ; time to save a new "old" value
test bx,word ptr savedand ; save on 0, check on anything else
jnz do_check_287_387 ; time to save a new "old" value
; save last value ; fpu stack is
fstp savedx ; x y ...
fst savedy ; y ...
dec savedincr ; time to lengthen the periodicity?
jnz per_check_287_387_ret ; if not 0, then skip
shl word ptr savedand,1 ; savedand = (savedand << 1) + 1
rcl word ptr savedand+2,1 ; savedand = (savedand << 1) + 1
add word ptr savedand,1 ; for longer periodicity
adc word ptr savedand+2,0 ; for longer periodicity
mov ax,nextsavedincr ; and restart counter
mov savedincr,ax ; and restart counter
ret ; y ...
do_check_287_387: ; fpu stack is
; x y ...
fsub savedx ; x-savedx y ...
fabs ; |x-savedx| y ...
fcomp closenuff ; y ...
fstsw ax
sahf
ja per_check_287_387_ret
fld st ; y y ...
fsub savedy ; y-savedy y ...
fabs ; |y-savedy| y ...
fcomp closenuff ; y ...
fstsw ax
sahf
ja per_check_287_387_ret
; caught a cycle!!!
mov word ptr oldcoloriter,-1 ; check periodicity immediately next time
mov word ptr oldcoloriter+2,-1 ; check periodicity immediately next time
mov ax,word ptr maxit
mov dx,word ptr maxit+2
mov word ptr realcoloriter,ax ; save unadjusted realcolor as maxit
mov word ptr realcoloriter+2,dx ; save unadjusted realcolor as maxit
sub dx,cx ; subtract half c
sbb ax,bx ; subtract half c
sub kbdcount,ax ; adjust the keyboard count
mov ax,periodicity_color ; set color
sub dx,dx
sub cx,cx ; flag to exit cx loop immediately
mov bx,cx
per_check_287_387_ret:
ret
periodicity_check_287_387 ENDP
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.386
.387
periodicity_check_386_387 PROC NEAR
; REMEMBER, the cx counter is counting BACKWARDS from maxit to 0
; fpu stack is
; y x Cx Cy b
fld st(1) ;
; x y ...
test ecx,savedand ; save on 0, check on anything else
jnz do_check_386_387 ; time to save a new "old" value
; save last value ; fpu stack is
fstp savedx ; x y ...
fst savedy ; y ...
dec savedincr ; time to lengthen the periodicity?
jnz per_check_386_387_ret ; if not 0, then skip
shl savedand,1 ; savedand = (savedand << 1) + 1
inc savedand ; for longer periodicity
mov ax,nextsavedincr ; and restart counter
mov savedincr,ax ; and restart counter
ret ; y ...
do_check_386_387: ; fpu stack is
; x y ...
fsub savedx ; x-savedx y ...
fabs ; |x-savedx| y ...
fcomp closenuff ; y ...
fstsw ax
sahf
ja per_check_386_387_ret
fld st ; y y ...
fsub savedy ; y-savedy y ...
fabs ; |y-savedy| y ...
fcomp closenuff ; y ...
fstsw ax
sahf
ja per_check_386_387_ret
; caught a cycle!!!
mov oldcoloriter,-1 ; check periodicity immediately next time
mov eax,maxit
mov realcoloriter,eax ; save unadjusted realcolor as maxit
sub eax,ecx ; subtract half c
sub kbdcount,ax ; adjust the keyboard count
sub eax,eax ; clear top half of eax for next
mov ax,periodicity_color ; set color
sub ecx,ecx ; flag to exit cx loop immediately
per_check_386_387_ret:
ret
periodicity_check_386_387 ENDP
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.8086
.8087
periodicity_check_87 PROC NEAR
; just like periodicity_check_287_387 except for the use of
; fstsw tmp_word
; instead of
; fstsw ax
; REMEMBER, the cx counter is counting BACKWARDS from maxit to 0
fld st(2) ; x y ...
test cx,word ptr savedand+2 ; save on 0, check on anything else
jnz do_check_87 ; time to save a new "old" value
test bx,word ptr savedand ; save on 0, check on anything else
jnz do_check_87 ; time to save a new "old" value
; save last value ; fpu stack is
; x y ...
fstp savedx ; y ...
fst savedy ; y ...
dec savedincr ; time to lengthen the periodicity?
jnz per_check_87_ret ; if not 0, then skip
shl word ptr savedand,1 ; savedand = (savedand << 1) + 1
rcl word ptr savedand+2,1 ; savedand = (savedand << 1) + 1
add word ptr savedand,1 ; for longer periodicity
adc word ptr savedand+2,0 ; for longer periodicity
mov ax,nextsavedincr ; and restart counter
mov savedincr,ax ; and restart counter
ret ; y ...
do_check_87: ; fpu stack is
; x y ...
fsub savedx ; x-savedx y ...
fabs ; |x-savedx| y ...
fcomp closenuff ; y ...
fstsw tmp_word
fwait
mov ax,tmp_word
sahf
ja per_check_87_ret
fld st ; y y ...
fsub savedy ; y-savedy y ...
fabs ; |y-savedy| y ...
fcomp closenuff ; y ...
fstsw tmp_word
fwait
mov ax,tmp_word
sahf
ja per_check_87_ret
; caught a cycle!!!
mov word ptr oldcoloriter,-1 ; check periodicity immediately next time
mov word ptr oldcoloriter+2,-1 ; check periodicity immediately next time
mov ax,word ptr maxit
mov dx,word ptr maxit+2
mov word ptr realcoloriter,ax ; save unadjusted realcolor as maxit
mov word ptr realcoloriter+2,dx ; save unadjusted realcolor as maxit
sub dx,cx ; subtract half c
sbb ax,bx ; subtract half c
sub kbdcount,ax ; adjust the keyboard count
mov ax,periodicity_color ; set color
sub dx,dx
sub cx,cx ; flag to exit cx loop immediately
mov bx,cx
per_check_87_ret:
ret
periodicity_check_87 ENDP
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.8086
.8087
epsilon_cross PROC NEAR
; fpu stack is either
; y x Cx Cy b (387)
; y 1 x Cx Cy b (287/87/emul)
cmp fpu,387
jb ec_load_x
fld st(1) ; if 387
jmp short ec_end_load_x
ec_load_x:
fld st(2) ; if 287/87/emul
ec_end_load_x: ; x y ...
fabs ; |x| y 1 x Cx Cy b
fcomp close ; y 1 x Cx Cy b
fstsw tmp_word
fwait
mov ax,tmp_word
sahf
jae no_x_epsilon_cross
mov ax,word ptr maxit ; x is close to y axis
mov dx,word ptr maxit+2 ; x is close to y axis
sub ax,bx ; leave 'times through loop' in ax,dx
sbb dx,cx ; leave 'times through loop' in ax,dx
; zero color fix
jnz zero_color_fix_1
cmp ax,0
jnz zero_color_fix_1
inc ax ; if (ax == 0 ) ax = 1
zero_color_fix_1:
mov word ptr realcoloriter,ax ; save unadjusted realcolor
mov word ptr realcoloriter+2,dx ; save unadjusted realcolor
sub kbdcount,ax ; adjust the keyboard count
mov ax,GREEN ;
sub dx,dx
sub cx,cx ; flag to end loop
mov bx,cx
mov word ptr oldcoloriter,bx ; don't check next time
mov word ptr oldcoloriter+2,cx ; don't check next time
ret ; return
no_x_epsilon_cross: ; y 1 x Cx Cy b
fld st ; y y 1 x Cx Cy b
fabs ; |y| y 1 x Cx Cy b
fcomp close ; y 1 x Cx Cy b
fstsw tmp_word
fwait
mov ax,tmp_word
sahf
jae no_y_epsilon_cross
mov ax,word ptr maxit ; y is close to x axis
mov dx,word ptr maxit+2 ; y is close to x axis
sub ax,bx ; leave 'times through loop' in ax,dx
sbb dx,cx ; leave 'times through loop' in ax,dx
; zero color fix
jnz zero_color_fix_2
cmp ax,0
jnz zero_color_fix_2
inc ax ; if (ax == 0 ) ax = 1
zero_color_fix_2:
mov word ptr realcoloriter,ax ; save unadjusted realcolor
mov word ptr realcoloriter+2,dx ; save unadjusted realcolor
sub kbdcount,ax ; adjust the keyboard count
mov ax,YELLOW
sub dx,dx
sub cx,cx ; flag to end loop
mov bx,cx
mov word ptr oldcoloriter,bx ; don't check next time
mov word ptr oldcoloriter+2,cx ; don't check next time
ret ; return
no_y_epsilon_cross:
ret
epsilon_cross ENDP
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.386
.387
epsilon_cross_386_387 PROC NEAR
; fpu stack is
; y x Cx Cy b
fld st(1) ;
fabs ; |x| y x Cx Cy b
fcomp close ; y x Cx Cy b
fstsw tmp_word
fwait
mov ax,tmp_word
sahf
jae no_x_epsilon_cross
mov eax,maxit ; x is close to y axis
sub eax,ecx ; leave 'times through loop' in eax
; zero color fix
jnz zero_color_fix_1
inc eax ; if (eax == 0 ) eax = 1
zero_color_fix_1:
mov realcoloriter,eax ; save unadjusted realcolor
sub kbdcount,ax ; adjust the keyboard count
mov eax,GREEN ;
sub ecx,ecx ; flag to end loop
mov oldcoloriter,ecx ; don't check next time
ret ; return
no_x_epsilon_cross: ; y 1 x Cx Cy b
fld st ; y y 1 x Cx Cy b
fabs ; |y| y 1 x Cx Cy b
fcomp close ; y 1 x Cx Cy b
fstsw tmp_word
fwait
mov ax,tmp_word
sahf
jae no_y_epsilon_cross
mov eax,maxit ; y is close to x axis
sub eax,ecx ; leave 'times through loop' in ax,dx
; zero color fix
jnz zero_color_fix_2
inc eax ; if (eax == 0 ) eax = 1
zero_color_fix_2:
mov realcoloriter,eax ; save unadjusted realcolor
sub kbdcount,ax ; adjust the keyboard count
mov eax,YELLOW
sub ecx,ecx ; flag to end loop
mov oldcoloriter,ecx ; don't check next time
ret ; return
no_y_epsilon_cross:
ret
epsilon_cross_386_387 ENDP
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.8086
.8087
show_orbit_xy PROC NEAR USES cx si di
local tmp_ten_byte_0:tbyte ; stupid klooge for MASM 5.1 LOCAL bug
local tmp_ten_byte_1:tbyte
local tmp_ten_byte_2:tbyte
local tmp_ten_byte_3:tbyte
local tmp_ten_byte_4:tbyte
local tmp_ten_byte_5:tbyte
local tmp_ten_byte_6:tbyte
; USES is needed because in all likelyhood, plot_orbit surely
; uses these registers. It's ok to have to push/pop's here in the
; orbits as speed is not crucial when showing orbits.
; fpu stack is either
; y x Cx Cy b (387)
; y 1 x Cx Cy b (287/87/emul)
cmp fpu,387
jb so_load_x
fld st(1) ; if 387
jmp short so_end_load_x
so_load_x:
fld st(2) ; if 287/87/emul
so_end_load_x:
; x y ...
; and needs to returned as
; y ...
fstp orbit_real ; y ...
fst orbit_imag ; y ...
mov ax,-1 ; color for plot orbit
push ax ; ...
; since the number fpu registers that plot_orbit() preserves is compiler
; dependant, it's best to fstp the entire stack into 10 byte memories
; and fld them back after plot_orbit() returns.
fstp tmp_ten_byte_1 ; store the stack in 80 bit form
fstp tmp_ten_byte_2
fstp tmp_ten_byte_3
fstp tmp_ten_byte_4
fstp tmp_ten_byte_5
cmp fpu,287 ; with 287/87/emul the stack is 6 high
jg no_store_6 ; with 387 it is only 5 high
fstp tmp_ten_byte_6
no_store_6:
fwait ; just to be safe
push word ptr orbit_imag+6 ; co-ordinates for plot orbit
push word ptr orbit_imag+4 ; ...
push word ptr orbit_imag+2 ; ...
push word ptr orbit_imag ; ...
push word ptr orbit_real+6 ; co-ordinates for plot orbit
push word ptr orbit_real+4 ; ...
push word ptr orbit_real+2 ; ...
push word ptr orbit_real ; ...
call far ptr plot_orbit ; display the orbit
add sp,9*2 ; clear out the parameters
cmp fpu,287
jg no_load_6
fld tmp_ten_byte_6 ; load them back in reverse order
no_load_6:
fld tmp_ten_byte_5
fld tmp_ten_byte_4
fld tmp_ten_byte_3
fld tmp_ten_byte_2
fld tmp_ten_byte_1
fwait ; just to be safe
ret
show_orbit_xy ENDP
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.8086
.8087
special_outside PROC NEAR
; When type casting floating point variables to integers in C, the decimal
; is truncated. When using FIST in asm, the value is rounded. Using
; "FSUB round_down_half" causes the values to be rounded down.
cmp outside,-2
jne not_real
fld newx
fsub round_down_half
fistp tmp_dword
add ax,7
adc dx,0
fwait
add ax,word ptr tmp_dword
adc dx,word ptr tmp_dword+2
jmp check_color
not_real:
cmp outside,-3
jne not_imag
fld newy
fsub round_down_half
fistp tmp_dword
add ax,7
adc dx,0
fwait
add ax,word ptr tmp_dword
adc dx,word ptr tmp_dword+2
jmp check_color
not_imag:
cmp outside,-4
jne not_mult
fld newy
ftst ; check to see if newy == 0
fstsw tmp_word
push ax ; save current ax value
fwait
mov ax,tmp_word
sahf
pop ax ; retrieve ax (does not affect flags)
jne non_zero_y
ret ; if y==0, return with normal ax
non_zero_y:
fdivr newx ; newx/newy
mov word ptr tmp_dword,ax
mov word ptr tmp_dword+2,dx
fimul tmp_dword ; (ax,dx)*newx/newy (Use FIMUL instead of MUL
fsub round_down_half ; to make it match the C code.)
fistp tmp_dword
fwait
mov ax,word ptr tmp_dword
mov dx,word ptr tmp_dword+2
jmp short check_color
not_mult:
cmp outside,-5
jne not_sum
fld newx
fadd newy ; newx+newy
fsub round_down_half
fistp tmp_dword
fwait
add ax,word ptr tmp_dword
adc dx,word ptr tmp_dword+2
not_sum:
cmp outside,-6 ; currently always equal, but put here
jne not_atan ; for future outside types
call near ptr FPUatan ; return with atan on FPU stack
fmul one_8_zero ; 180*Angle
fldpi ; pi 180*Angle
fdiv ; 180*Angle/pi
fabs
fsub round_down_half
fistp tmp_dword
fwait
mov ax,word ptr tmp_dword
mov dx,word ptr tmp_dword+2
not_atan:
check_color:
cmp dx,word ptr maxit+2 ; use UNSIGNED comparison
jb special_outside_ret ; color < 0 || color > maxit
cmp ax,word ptr maxit ; use UNSIGNED comparison
jbe special_outside_ret ; color < 0 || color > maxit
sub ax,ax ; ax = 0
mov dx,ax ; dx = 0
special_outside_ret:
ret
special_outside ENDP
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.386
.387
special_outside_386_387 PROC NEAR
; When type casting floating point variables to integers in C, the decimal
; is truncated. When using FIST in asm, the value is rounded. Using
; "FSUB round_down_half" causes the values to be rounded down.
cmp outside,-2
jne not_real
fld newx
fsub round_down_half
fistp tmp_dword
add eax,7
fwait
add eax,tmp_dword
jmp check_color
not_real:
cmp outside,-3
jne not_imag
fld newy
fsub round_down_half
fistp tmp_dword
add eax,7
fwait
add eax,tmp_dword
jmp check_color
not_imag:
cmp outside,-4
jne not_mult
fld newy
ftst ; check to see if newy == 0
fstsw tmp_word
push ax ; save current ax value
fwait
mov ax,tmp_word
sahf
pop ax ; retrieve ax (does not affect flags)
jne non_zero_y
ret ; if y==0, return with normal ax
non_zero_y:
fdivr newx ; newx/newy
mov tmp_dword,eax
fimul tmp_dword ; (ax,dx)*newx/newy (Use FIMUL instead of MUL
fsub round_down_half ; to make it match the C code.)
fistp tmp_dword
fwait
mov eax,tmp_dword
jmp short check_color
not_mult:
cmp outside,-5
jne not_sum
fld newx
fadd newy ; newx+newy
fsub round_down_half
fistp tmp_dword
fwait
add eax,tmp_dword
not_sum:
cmp outside,-6 ; currently always equal, but put here
jne not_atan ; for future outside types
fld newy ; newy
fld newx ; newx newy
fpatan ; arctan(y/x)
fmul one_8_zero ; 180*atan
fldpi ; pi 180*atan
fdiv ; 180*atan/pi
fabs
fsub round_down_half
fistp tmp_dword
fwait
mov eax,tmp_dword
not_atan:
check_color:
cmp eax,maxit ; use UNSIGNED comparison
jbe special_outside_ret ; color < 0 || color > maxit
sub eax,eax ; eax = 0
special_outside_ret:
ret
special_outside_386_387 ENDP
.8086 ;just to be sure
.8087
FPUatan PROC NEAR
; This is derived from FPUcplxlog in fpu087.asm
; The arctan is returned on the FPU stack
LOCAL Status:word
mov ax, word ptr newy+6
or ax, word ptr newx+6
jnz NotBothZero
fldz
jmp atandone
NotBothZero:
fld newy ; newy
fld newx ; newx newy
mov dh, BYTE PTR newx+7
or dh, dh
jns ChkYSign
fchs ; |newx| newy
ChkYSign:
mov dl, BYTE PTR newy+7
or dl, dl
jns ChkMagnitudes
fxch ; newy |newx|
fchs ; |newy| |newx|
fxch ; |newx| |newy|
ChkMagnitudes:
fcom st(1) ; |newx| |newy|
fstsw Status
test Status, 4500h
jz XisGTY
test Status, 4000h
jz XneY
; newx = newy and atan = pi/4
fstp st ; newy
fstp st ; empty
fldpi ; pi
fdiv _4_ ; pi/4
jmp short ChkSignZ
XneY:
fxch ; newy newx
fpatan ; pi/2 - Angle
fldpi ; pi, pi/2 - Angle
fdiv _2_ ; pi/2, pi/2 - Angle
fsubr ; Angle
jmp short ChkSignZ
XisGTY:
fpatan ; pi-Angle or Angle+pi
ChkSignZ:
or dh, dh
js NegX
or dl, dl
jns short atandone
fchs
jmp short atandone
NegX:
or dl, dl
js QuadIII
fldpi ; pi, pi-Angle
fsubr ; Angle
jmp short atandone
QuadIII:
fldpi ; pi, Angle+pi
fsub ; Angle
atandone:
ret ; Leave result on FPU stack and return
FPUatan ENDP
END
