brender-1997/pentprim/T_PIA.ASM
2022-05-03 14:31:40 -07:00

672 lines
10 KiB
NASM

;; Copyright (c) 1991,1993-1995 Argonaut Technologies Limited. All rights reserved.
;;
;; $Id: T_PIA.ASM 1.1 1996/09/26 19:04:08 JOHNG Exp $
;; $Locker: $
;;
;; Trapezoid rendering for arbitary width texture mapping
;;
.386p
.model c,flat
include drv.inc
WRAP equ 1
WRAPROW equ 1
TRANSP equ 1
.data
noffset dd ?
.code
; Macro to increment those parts of the per scan line
; increment that depend on whether there has been a carry
; from the fractional part of the current screen x coordinate
scan_inc macro carry,LIGHT,SBPP
local lab2
if LIGHT
mov ebx,work.pi.current
endif ; LIGHT
if LIGHT
mov ecx,work.pi.d_&carry&
endif ; LIGHT
add ebx,ecx
mov work.pi.current,ebx
mov ebx,work.awsl.u_current
mov ecx,work.awsl.du_&carry&
mov ebp,work.awsl.source_current
mov edi,work.awsl.dsource_&carry&
add ebx,ecx ; work.awsl.u_current += work.awsl.dsource_&carry&
sbb ecx,ecx ; Save -carry
add ebp,edi ; work.awsl.source_current += work.awsl.dsource_&carry&
mov work.awsl.u_current,ebx
if WRAP
mov ebx,dword ptr work.awsl.u_int_current
add ebx,work.awsl.du_int_&carry&
sub ebx,ecx ; work.awsl.u_int_current += carry;
mov dword ptr work.awsl.u_int_current,ebx
endif ; WRAP
ifidni <SBPP>,<2>
shl ecx,1
elseifidni <SBPP>,<3>
lea ecx,[ecx+ecx*2]
elseifidni <SBPP>,<4>
shl ecx,2
endif ; <SBPP>
sub ebp,ecx ; work.awsl.source_current += carry*SBPP
mov ebx,work.awsl.v_current
mov ecx,work.awsl.dv_&carry&
add ebx,ecx
mov work.awsl.v_current,ebx
jnc lab2
mov edi,work.texture.stride_b
add ebp,edi
lab2:
mov work.awsl.source_current,ebp
endm
TriangleRender macro fn,LIGHT,SBPP,DBPP,BUMP
fn proc uses eax ebx ecx edx esi edi ebp
outer:
mov eax,work.awsl.edge
mov ebx,[eax].scan_edge.count
test ebx,ebx
jz exit
dec ebx ; work.awsl.edge->count--
mov [eax].scan_edge.count,ebx
if BUMP
mov ecx,work.bump.base
sub ecx,work.texture.base
mov noffset,ecx
endif
mov edi,work.awsl.start
mov ebx,work.awsl._end
cmp edi,ebx
mov eax,work.awsl.u_current
mov ebx,work.awsl.v_current
mov al,byte ptr work.awsl.u_int_current
if LIGHT
mov ecx,work.pi.current
mov work.pi.currentpix,ecx
endif ; LIGHT
mov ah,byte ptr work.awsl.u_int_current+1
mov esi,work.awsl.source_current
jge scan_back
; Forward scan
loopf:
mov ecx,work.awsl._end
cmp edi,ecx
jge next
if TRANSP
ifidni <SBPP>,<1>
mov dl,[esi]
test dl,dl
jz failf ; Skip if transparent
elseifidni <SBPP>,<2>
mov dl,[esi]
mov dh,1[esi]
or dl,dh
jz failf
elseifidni <SBPP>,<3>
mov dl,[esi]
mov dh,1[esi]
or dl,dh
mov dh,2[esi]
or dl,dh
jz failf
endif ; <SBPP>
endif ; TRANSP
if LIGHT
xor ecx,ecx
mov ch,byte ptr work.pi.currentpix+2 ; Get lighting index
mov cl,[esi] ; Get texel
mov edx,work.shade_table
ifidni <DBPP>,<1>
add edx,ecx
mov bl,[edx] ; Light texel
mov [edi],bl ; Store texel
inc edi ; ptr++
elseifidni <DBPP>,<2>
mov bx,[edx+ecx*2] ; Light texel
mov [edi],bx ; Store texel
lea edi,2[edi] ; ptr++
elseifidni <DBPP>,<3>
mov bx,[edx+ecx*4] ; Light texel
mov [edi],bx ; Store texel
mov bl,2[edx+ecx*4] ; Light texel
mov 2[edi],bl ; Store texel
lea edi,3[edi] ; ptr++
else ; <DBPP>
SHOULDN'T GET HERE
add edi,DBPP
endif ; <DBPP>
mov edx,work.pi.currentpix
mov ecx,work.pi.grad_x ; i += di
add edx,ecx
mov work.pi.currentpix,edx
jmp contf
failf:
ifidni <DBPP>,<1>
inc edi ; ptr++
else ; <DBPP>
add edi,DBPP
endif ; <DBPP>
mov edx,work.pi.currentpix
mov ecx,work.pi.grad_x ; i += di
add edx,ecx
mov work.pi.currentpix,edx
elseif BUMP
; Bump mapping
xor ecx,ecx
mov cl,[esi] ; Get texel
mov edx,noffset
mov dl,[esi+edx] ; Get normal
and edx,0ffh
add edx,work.lighting_table ; Calculate light level from normal
mov ch,[edx]
mov edx,work.shade_table
mov cl,[edx+ecx] ; Light texel
mov [edi],cl
ifidni <DBPP>,<1>
inc edi ; ptr++
else ; <DBPP>
add edi,DBPP
endif ; <DBPP>
jmp contf
failf:
ifidni <DBPP>,<1>
inc edi ; ptr++
else ; <DBPP>
add edi,DBPP
endif ; <DBPP>
else ; LIGHT
; No lighting
ifidni <SBPP>,<1>
mov cl,[esi] ; Get texel
mov [edi],cl
elseifidni <SBPP>,<2>
mov cl,[esi]
mov ch,1[esi]
mov [edi],cl
mov 1[edi],ch
elseifidni <SBPP>,<3>
mov cl,[esi] ; Get texel
mov [edi],cl
mov ch,1[esi]
mov 1[edi],ch ; Store green
mov cl,2[esi]
mov 2[edi],cl ; Store red
elseifidni <SBPP>,<4>
mov ecx,[esi]
mov [edi],ecx
endif ; <SBPP>
ifidni <DBPP>,<1>
inc edi ; ptr++
else ; <DBPP>
add edi,DBPP
endif ; <DBPP>
jmp contf
failf:
ifidni <DBPP>,<1>
inc edi ; ptr++
else ; <DBPP>
add edi,DBPP
endif ; <DBPP>
endif ; LIGHT
contf:
; Redo this with high and low halfwords of du swapped
mov ecx,work.awsl.du
add eax,ecx ; u += du
mov ecx,work.awsl.dsource
sbb edx,edx ; edx = -carry
add esi,ecx
mov ecx,work.awsl.du_int
sub eax,edx ; work.awsl.du += carry
ifidni <SBPP>,<2>
shl edx,1
elseifidni <SBPP>,<3>
lea edx,[edx+2*edx]
elseifidni <SBPP>,<4>
shl edx,2
endif ; <SBPP>
sub esi,edx ; esi += carry
add eax,ecx ; u_int += du_int
mov ecx,work.awsl.dv
mov edx,work.texture.stride_b;
add ebx,ecx
jnc nostridef
add esi,edx
nostridef:
test ah,ah
jl nowidthf
mov ecx,work.texture.width_p
add eax,ecx
ifidni <SBPP>,<1>
add esi,ecx
elseifidni <SBPP>,<2>
lea esi,[esi+2*ecx]
elseifidni <SBPP>,<3>
lea ecx,[ecx+2*ecx]
add esi,ecx
elseifidni <SBPP>,<4>
lea esi,[esi+4*ecx]
endif ; <SBPP>
nowidthf:
mov ecx,work.texture.base
cmp esi,ecx ; Have we underrun?
jge nosizef
mov ecx,work.texture._size
add esi,ecx
nosizef:
jmp loopf
scan_back:
; Backwards scan
loopb:
mov ecx,work.awsl._end
cmp edi,ecx
jle next
sub ecx,edx
if LIGHT
mov edx,work.pi.currentpix
endif
if LIGHT
mov ecx,work.pi.grad_x ; i += di
sub edx,ecx
mov work.pi.currentpix,edx
endif
; Redo this with high and low halfwords of du swapped
mov ecx,work.awsl.du
add eax,ecx ; u += du
mov ecx,work.awsl.dsource
sbb edx,edx ; edx = -carry
add esi,ecx
mov ecx,work.awsl.du_int
sub eax,edx
add eax,ecx ; u_int += du_int
ifidni <SBPP>,<1>
sub esi,edx
elseifidni <SBPP>,<2>
shl edx,1
sub esi,edx
elseifidni <SBPP>,<3>
lea edx,[edx+edx*2]
sub esi,edx
elseifidni <SBPP>,<4>
shl edx,2
sub esi,edx
endif
mov ecx,work.awsl.dv
add ebx,ecx
jnc nostrideb
mov ecx,work.texture.stride_b
add esi,ecx
nostrideb:
test ah,ah
jl nowidthb
mov ecx,work.texture.width_p
add eax,ecx
ifidni <SBPP>,<1>
add esi,ecx
elseifidni <SBPP>,<2>
lea esi,[esi+2*ecx]
elseifidni <SBPP>,<3>
lea ecx,[ecx+2*ecx]
add esi,ecx
elseifidni <SBPP>,<4>
lea esi,[esi+4*ecx]
endif ; <SBPP>
nowidthb:
mov ecx,work.texture.base
cmp esi,ecx
jge nosizeb
mov ecx,work.texture._size
add esi,ecx
nosizeb:
ifidni <DBPP>,<1>
dec edi ; ptr += 1
else ; <DBPP>
sub edi,DBPP
endif ; <DBPP>
if TRANSP
ifidni <SBPP>,<1>
mov bl,[esi]
test bl,bl
jz loopb ; Skip if transparent
elseifidni <SBPP>,<2>
mov bl,[esi]
mov bh,1[esi]
or bl,bh
jz failb
elseifidni <SBPP>,<3>
mov bl,[esi]
mov bh,1[esi]
or bl,bh
mov bh,2[esi]
or bl,bh
jz failb
endif ; <SBPP>
endif ; <TRANSP>
if LIGHT
xor ecx,ecx
mov ch,byte ptr work.pi.currentpix+2
mov edx,work.shade_table
endif ; <LIGHT>
ifidni <SBPP>,<1>
mov cl,[esi] ; Get texel
ifidni <DBPP>,<1>
if LIGHT
mov cl,[ecx+edx] ; Light texel
endif
if BUMP
and ecx,0ffh
mov edx,noffset
mov dl,[esi+edx]
and edx,0ffh
add edx,work.lighting_table ; Calculate light level from normal
mov ch,[edx]
mov edx,work.shade_table
mov cl,[edx+ecx] ; Light texel
endif
mov [edi],cl
elseifidni <DBPP>,<2>
if LIGHT
mov cx,[edx+ecx*2]
mov [edi],cx
endif
elseifidni <DBPP>,<3>
if LIGHT
mov bx,[edx+ecx*4]
mov [edi],bx
mov bl,2[edx+ecx*4]
mov 2[edi],bl
endif
endif ; DBPP
elseifidni <SBPP>,<2>
mov cl,[esi]
mov [edi],cl ; Store texel
mov cl,1[esi]
mov 1[edi],cl ; Store texel
elseifidni <SBPP>,<3>
mov ecx,[esi]
mov [edi],cl ; Store texel
mov 1[edi],ch ; Store texel
ror ecx,16
mov 2[edi],cl ; Store texel
elseifidni <SBPP>,<4>
mov ecx,[esi]
mov [edi],ecx ; Store texel
endif ; <SBPP>
failb:
jmp loopb
next:
; Per scan line updates
assume eax:ptr scan_edge
mov eax,work.awsl.edge
mov ebx,[eax].f
mov ecx,[eax].d_f
add ebx,ecx ; edge->f += edge->d_f
mov [eax].f,ebx
mov ecx,[eax].d_i
mov ebx,work.awsl._end
ifidni <DBPP>,<1>
adc ebx,ecx ; work.awsl._end += edge->d_i+carry
elseifidni <DBPP>,<2>
adc ecx,0
shl ecx,1
add ebx,ecx
elseifidni <DBPP>,<3>
adc ecx,0
lea ecx,[ecx+2*ecx]
add ebx,ecx ; work.awsl._end += 3*(edge->d_i+carry)
elseifidni <DBPP>,<4>
adc ecx,0
shl ecx,2
add ebx,ecx
endif ; <DBPP>
mov work.awsl._end,ebx
mov ebx,work.main.f
mov ecx,work.main.d_f
add ebx,ecx
mov work.main.f,ebx
mov ebx,work.awsl.start
mov ecx,work.main.d_i
jnc noscarry
; if (carry) ...
adc ecx,0
lea esi,[esi+2*ecx]
ifidni <DBPP>,<1>
add ebx,ecx
elseifidni <DBPP>,<2>
lea ebx,[ebx+2*ecx]
elseifidni <DBPP>,<3>
lea ecx,[ecx+2*ecx]
add ebx,ecx
elseifidni <DBPP>,<4>
lea ebx,[ebx+4*ecx]
endif
mov work.awsl.start,ebx
scan_inc carry,LIGHT,SBPP
jmp cont
; ... else ...
noscarry:
lea esi,[esi+2*ecx]
ifidni <DBPP>,<1>
add ebx,ecx
elseifidni <DBPP>,<2>
lea ebx,[ebx+2*ecx]
elseifidni <DBPP>,<3>
lea ecx,[ecx+2*ecx]
add ebx,ecx
elseifidni <DBPP>,<4>
lea ebx,[ebx+4*ecx]
endif
mov work.awsl.start,ebx
scan_inc nocarry,LIGHT,SBPP
; ... endif
cont:
mov ebx,dword ptr work.awsl.u_int_current
test bh,bh ; Test sign of low halfword
jl lab1
mov ecx,work.texture.width_p
add ebx,ecx
mov dword ptr work.awsl.u_int_current,ebx
mov ebx,work.awsl.source_current
ifidni <SBPP>,<1>
add ebx,ecx
elseifidni <SBPP>,<2>
lea ebx,[ebx+2*ecx]
elseifidni <SBPP>,<3>
lea ecx,[ecx+2*ecx]
add ebx,ecx
elseifidni <SBPP>,<4>
lea ebx,[ebx+4*ecx]
endif
mov work.awsl.source_current,ebx
lab1:
mov ebx,work.awsl.source_current
mov ecx,work.texture.base
cmp ebx,ecx
jge outer
mov ecx,work.texture._size
add ebx,ecx
mov work.awsl.source_current,ebx
jmp outer
exit:
ret
fn endp
endm
if PARTS and PART_8
TriangleRender TrapezoidRenderPITA,0,1,1,0
endif
if PARTS and PART_BUMP
TriangleRender TrapezoidRenderPITAN,0,1,1,1
endif
if PARTS and PART_8
TriangleRender TrapezoidRenderPITIA,1,1,1,0
endif
if PARTS and PART_15
TriangleRender TrapezoidRenderPITA15,0,2,2,0
endif
if PARTS and PART_24
TriangleRender TrapezoidRenderPITA24,0,3,3,0
endif
if PARTS and PART_24
TriangleRender TrapezoidRenderPITIA_RGB_888,1,1,3,0
endif
if PARTS and PART_15
TriangleRender TrapezoidRenderPITIA_RGB_555,1,1,2,0
endif
end