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Amiga ACS 1998 #6
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tmap_ll.asm
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Assembly Source File
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1998-06-08
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12KB
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487 lines
;THE COMPUTER CODE CONTAINED HEREIN IS THE SOLE PROPERTY OF PARALLAX
;SOFTWARE CORPORATION ("PARALLAX"). PARALLAX, IN DISTRIBUTING THE CODE TO
;END-USERS, AND SUBJECT TO ALL OF THE TERMS AND CONDITIONS HEREIN, GRANTS A
;ROYALTY-FREE, PERPETUAL LICENSE TO SUCH END-USERS FOR USE BY SUCH END-USERS
;IN USING, DISPLAYING, AND CREATING DERIVATIVE WORKS THEREOF, SO LONG AS
;SUCH USE, DISPLAY OR CREATION IS FOR NON-COMMERCIAL, ROYALTY OR REVENUE
;FREE PURPOSES. IN NO EVENT SHALL THE END-USER USE THE COMPUTER CODE
;CONTAINED HEREIN FOR REVENUE-BEARING PURPOSES. THE END-USER UNDERSTANDS
;AND AGREES TO THE TERMS HEREIN AND ACCEPTS THE SAME BY USE OF THIS FILE.
;COPYRIGHT 1993-1998 PARALLAX SOFTWARE CORPORATION. ALL RIGHTS RESERVED.
;
; $Source: f:/miner/source/texmap/rcs/tmap_ll.asm $
; $Revision: 1.10 $
; $Author: john $
; $Date: 1995/02/20 18:22:54 $
;
; Linear, lighted texture mapper inner loop.
;
; $Log: tmap_ll.asm $
; Revision 1.10 1995/02/20 18:22:54 john
; Put all the externs in the assembly modules into tmap_inc.asm.
; Also, moved all the C versions of the inner loops into a new module,
; scanline.c.
;
; Revision 1.9 1995/02/20 17:09:06 john
; Added code so that you can build the tmapper with no assembly!
;
; Revision 1.8 1994/11/19 23:52:56 mike
; rip out big unrolled loop to save 25K....remember when we cared more about speed?
;
; Revision 1.7 1994/11/12 16:39:41 mike
; jae to ja.
;
; Revision 1.6 1994/03/14 15:45:08 mike
; streamline code.
;
; Revision 1.5 1994/01/24 13:13:12 mike
; dithering.
;
; Revision 1.4 1994/01/14 14:02:47 mike
; *** empty log message ***
;
; Revision 1.3 1993/12/17 20:00:16 mike
; Change default setting of dither_intensity_lighting from 1 to 0
;
; Revision 1.2 1993/11/22 10:24:50 mike
; *** empty log message ***
;
; Revision 1.1 1993/09/08 17:29:52 mike
; Initial revision
;
;
;
.386
public asm_tmap_scanline_lin_lighted_
include tmap_inc.asm
_DATA SEGMENT DWORD PUBLIC USE32 'DATA'
ALLOW_DITHERING equ 1
_fx_dl_dx1 dd ?
_fx_dl_dx2 dd ?
_loop_count dd ?
_DATA ENDS
DGROUP GROUP _DATA
_TEXT SEGMENT DWORD PUBLIC USE32 'CODE'
ASSUME DS:_DATA
ASSUME CS:_TEXT
; --------------------------------------------------------------------------------------------------
; Enter:
; _xleft fixed point left x coordinate
; _xright fixed point right x coordinate
; _y fixed point y coordinate
; _pixptr address of source pixel map
; _u fixed point initial u coordinate
; _v fixed point initial v coordinate
; _du_dx fixed point du/dx
; _dv_dx fixed point dv/dx
; for (x = (int) xleft; x <= (int) xright; x++) {
; _setcolor(read_pixel_from_tmap(srcb,((int) (u/z)) & 63,((int) (v/z)) & 63));
; _setpixel(x,y);
;
; u += du_dx;
; v += dv_dx;
; z += dz_dx;
; }
align 4
asm_tmap_scanline_lin_lighted_:
push es
push fs
pusha
mov es,_pixel_data_selector ; selector[0*2]
mov fs,_gr_fade_table_selector ; selector[1*2] ; fs = bmd_fade_table
; Setup for loop: _loop_count iterations = (int) xright - (int) xleft
; esi source pixel pointer = pixptr
; edi initial row pointer = y*320+x
; set esi = pointer to start of texture map data
mov esi,_pixptr
; set edi = address of first pixel to modify
mov edi,_fx_y ; this is actually an int
cmp edi,_window_bottom
ja all_done
imul edi,_bytes_per_row
mov ebx,_fx_xleft
test ebx,ebx
jns ebx_ok
sub ebx,ebx
ebx_ok:
add edi,ebx
add edi,write_buffer
; set _loop_count = # of iterations
mov eax,_fx_xright
cmp eax,_window_right
jl eax_ok1
mov eax,_window_right
eax_ok1: cmp eax,_window_left
jg eax_ok2
mov eax,_window_left
eax_ok2:
sub eax,ebx
js all_done
cmp eax,_window_width
jbe _ok_to_do
mov eax,_window_width
_ok_to_do:
mov _loop_count,eax
; edi destination pixel pointer
mov ecx,offset _lighting_tables
mov eax,_fx_u ; get 32 bit u coordinate
shr eax,6 ; get 6:10 int:frac u coordinate into low word
mov ebp,_fx_v ; get 32 bit v coordinate
shl ebp,10 ; put 6:10 int:frac into high word
mov bp,ax ; put u coordinate in low word
mov eax,_fx_du_dx ; get 32 bit delta u
shr eax,6 ; get 6:10 int:frac delta u into low word
mov edx,_fx_dv_dx ; get 32 bit delta v
shl edx,10 ; put 6:10 int:frac into high word
mov dx,ax ; put delta u in low word
sar dword ptr _fx_dl_dx,8
jns dl_dx_ok
inc _fx_dl_dx ; round towards 0 for negative deltas
dl_dx_ok:
if ALLOW_DITHERING
; do dithering, use lighting values which are .5 less than and .5 more than actual value
mov ebx,80h ; assume dithering on
test _dither_intensity_lighting,-1
jne do_dither
sub ebx,ebx ; no dithering
do_dither:
mov eax,_fx_dl_dx
add eax,ebx ; add 1/2
mov _fx_dl_dx1,eax
sub eax,ebx
sub eax,ebx
mov _fx_dl_dx2,eax
mov ebx,_fx_xleft
xor ebx,_fx_y
and ebx,1
jne dith_1
xchg eax,_fx_dl_dx1
dith_1: mov _fx_dl_dx2,eax
endif
mov ebx,_fx_l
; lighting values are passed in fixed point, but need to be in 8 bit integer, 8 bit fraction so we can easily
; get the integer by reading %bh
sar ebx,8
test _transparency_on,-1
jne do_transparency_ll
;; esi, ecx should be free
loop_test = 1 ; set to 1 to run as loop for better profiling
if loop_test
mov esi,_fx_dl_dx
mov ecx,_loop_count
inc ecx
shr ecx,1
je one_more_pix
pushf
align 4
loop1:
mov eax,ebp ; get u, v
shr eax,26 ; shift out all but int(v)
shld ax,bp,6 ; shift in u, shifting up v
add ebp,edx ; u += du, v += dv
mov al,es:[eax] ; get pixel from source bitmap
mov ah,bh ; get lighting table
add ebx,esi ; _fx_dl_dx ; update lighting value
mov al,fs:[eax] ; xlat pixel through lighting tables
mov [edi],al ; write pixel...
inc edi ; ...and advance
; --- ---
mov eax,ebp ; get u, v
shr eax,26 ; shift out all but int(v)
shld ax,bp,6 ; shift in u, shifting up v
add ebp,edx ; u += du, v += dv
mov al,es:[eax] ; get pixel from source bitmap
mov ah,bh ; get lighting table
add ebx,esi ; _fx_dl_dx ; update lighting value
mov al,fs:[eax] ; xlat pixel through lighting tables
mov [edi],al ; write pixel...
inc edi ; ...and advance
dec ecx ; _loop_count
jne loop1
popf
jnc all_done
one_more_pix: mov eax,ebp ; get u, v
shr eax,26 ; shift out all but int(v)
shld ax,bp,6 ; shift in u, shifting up v
mov al,es:[eax] ; get pixel from source bitmap
mov ah,bh ; get lighting table
mov al,fs:[eax] ; xlat pixel through lighting tables
mov [edi],al ; write pixel...
all_done: popa
pop fs
pop es
ret
else
; usage:
; eax work
; ebx lighting value
; ecx _lighting_tables
; edx du, dv 6:10:6:10
; ebp u, v coordinates 6:10:6:10
; esi pointer to source bitmap
; edi write address
_size = (_end1 - _start1)/num_iters
; note: if eax is odd, you will not be writing the last pixel, you must clean up at the end
if ALLOW_DITHERING
mov eax,_loop_count
shr eax,1
neg eax
add eax,num_iters
else
mov eax,num_iters
sub eax,_loop_count
endif
imul eax,eax,dword ptr _size
add eax,offset _start1
jmp eax
align 4
_start1:
; usage:
; eax work
; ebx lighting value
; ecx _lighting_tables
; edx du, dv 6:10:6:10
; ebp u, v coordinates 6:10:6:10
; esi pointer to source bitmap
; edi write address
; do all but the last pixel in the unwound loop, last pixel done separately because less work is needed
rept num_iters
if 1
;**; inner loop if lighting value is constant
;**; can be optimized if source bitmap pixels are stored as words, then the mov ah,bh is not necessary
;** mov eax,ebp ; get u, v
;** shr eax,26 ; shift out all but int(v)
;** shld ax,bp,6 ; shift in u, shifting up v
;**
;** add ebp,edx ; u += du, v += dv
;**
;** mov al,[esi+eax] ; get pixel from source bitmap
;** mov ah,bh ; get lighting table
;** mov al,[ecx+eax] ; xlat pixel through lighting tables
;** mov [edi],al ; write pixel...
;** inc edi ; ...and advance
if ALLOW_DITHERING
; dithering
; loop contains two iterations which must be the same length
mov eax,ebp ; get u, v
shr eax,26 ; shift out all but int(v)
shld ax,bp,6 ; shift in u, shifting up v
add ebp,edx ; u += du, v += dv
mov al,[esi+eax] ; get pixel from source bitmap
mov ah,bh ; get lighting table
add ebx,_fx_dl_dx1 ; update lighting value
mov al,[ecx+eax] ; xlat pixel through lighting tables
mov [edi],al ; write pixel...
inc edi ; ...and advance
; second iteration
mov eax,ebp ; get u, v
shr eax,26 ; shift out all but int(v)
shld ax,bp,6 ; shift in u, shifting up v
add ebp,edx ; u += du, v += dv
mov al,[esi+eax] ; get pixel from source bitmap
mov ah,bh ; get lighting table
add ebx,_fx_dl_dx2 ; update lighting value
mov al,[ecx+eax] ; xlat pixel through lighting tables
mov [edi],al ; write pixel...
inc edi ; ...and advance
else
mov eax,ebp ; get u, v
shr eax,26 ; shift out all but int(v)
shld ax,bp,6 ; shift in u, shifting up v
add ebp,edx ; u += du, v += dv
mov al,[esi+eax] ; get pixel from source bitmap
mov ah,bh ; get lighting table
add ebx,_fx_dl_dx ; update lighting value
mov al,[ecx+eax] ; xlat pixel through lighting tables
mov [edi],al ; write pixel...
inc edi ; ...and advance
endif
else
;obsolete: ; version which assumes segment overrides are in place (which they are obviously not)
;obsolete: mov eax,ebp ; get u, v
;obsolete: shr eax,26 ; shift out all but int(v)
;obsolete: shld ax,bp,6 ; shift in u, shifting up v
;obsolete:
;obsolete: add ebp,edx ; u += du, v += dv
;obsolete:
;obsolete: mov al,[eax] ; get pixel from source bitmap
;obsolete: mov ah,bh ; get lighting table
;obsolete: add ebx,esi ; update lighting value
;obsolete: mov al,[eax] ; xlat pixel through lighting tables
;obsolete: mov [edi],al ; write pixel...
;obsolete: inc edi ; ...and advance
endif
endm
_end1:
; now do the leftover pixel
mov eax,ebp
shr eax,26 ; shift in v coordinate
shld ax,bp,6 ; shift in u coordinate while shifting up v coordinate
mov al,[esi+eax] ; get pixel from source bitmap
mov ah,bh ; get lighting table
or ah,ah
jns ok1
sub ah,ah
ok1:
mov al,_lighting_tables[eax] ; xlat pixel through lighting tables
mov [edi],al ; write pixel...
_none_to_do: popa
pop fs
pop es
ret
endif
; -- Code to get rgb 5 bits integer, 5 bits fraction value into 5 bits integer (for each gun)
; suitable for inverse color lookup
;**__test:
;** int 3
;**; rrrrrfffffrrrrrfffffxxbbbbbfffff
;** mov eax,11111001001010101110101101110111b
;** and eax,11111000001111100000001111100000b
;** shld ebx,eax,15
;** or bx,ax
;; esi, ecx should be free
do_transparency_ll:
mov esi,_fx_dl_dx
mov ecx,_loop_count
inc ecx
shr ecx,1
je one_more_pix2
pushf
align 4
loop1a:
mov eax,ebp ; get u, v
shr eax,26 ; shift out all but int(v)
shld ax,bp,6 ; shift in u, shifting up v
add ebp,edx ; u += du, v += dv
mov al,es:[eax] ; get pixel from source bitmap
cmp al,255
je skip1a
mov ah,bh ; get lighting table
add ebx,esi ; _fx_dl_dx ; update lighting value
mov al,fs:[eax] ; xlat pixel through lighting tables
mov [edi],al ; write pixel...
skip1a: inc edi ; ...and advance
; --- ---
mov eax,ebp ; get u, v
shr eax,26 ; shift out all but int(v)
shld ax,bp,6 ; shift in u, shifting up v
add ebp,edx ; u += du, v += dv
mov al,es:[eax] ; get pixel from source bitmap
cmp al,255
je skip2a
mov ah,bh ; get lighting table
add ebx,esi ; _fx_dl_dx ; update lighting value
mov al,fs:[eax] ; xlat pixel through lighting tables
mov [edi],al ; write pixel...
skip2a: inc edi ; ...and advance
dec ecx ; _loop_count
jne loop1a
popf
jnc all_done_1
one_more_pix2: mov eax,ebp ; get u, v
shr eax,26 ; shift out all but int(v)
shld ax,bp,6 ; shift in u, shifting up v
mov al,es:[eax] ; get pixel from source bitmap
cmp al,255
je skip3a
mov ah,bh ; get lighting table
mov al,fs:[eax] ; xlat pixel through lighting tables
mov [edi],al ; write pixel...
skip3a:
all_done_1: popa
pop fs
pop es
ret
_TEXT ends
end