588 lines
No EOL
9.3 KiB
NASM
588 lines
No EOL
9.3 KiB
NASM
;; Copyright (c) 1991,1993-1995 Argonaut Technologies Limited. All rights reserved.
|
||
;;
|
||
;; $Id: t_piza.asm 1.1 1995/08/31 16:52:47 sam Exp $
|
||
;; $Locker: $
|
||
;;
|
||
;; Trapezoid rendering for arbitary width texture mapping
|
||
;;
|
||
|
||
.386p
|
||
.model c,flat
|
||
include zb.inc
|
||
|
||
WRAP equ 1
|
||
WRAPROW 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,BPP
|
||
local lab2
|
||
|
||
if LIGHT
|
||
mov ebx,zb.pi.current
|
||
endif ; LIGHT
|
||
|
||
if LIGHT
|
||
mov ecx,zb.pi.d_&carry&
|
||
endif ; LIGHT
|
||
|
||
add ebx,ecx
|
||
mov esi,zb.pz.current
|
||
mov edi,zb.pz.d_&carry&
|
||
add esi,edi
|
||
mov zb.pz.current,esi
|
||
|
||
mov zb.pi.current,ebx
|
||
|
||
mov ebx,zb.awsl.u_current
|
||
mov ecx,zb.awsl.du_&carry&
|
||
mov ebp,zb.awsl.source_current
|
||
mov edi,zb.awsl.dsource_&carry&
|
||
add ebx,ecx ; zb.awsl.u_current += zb.awsl.dsource_&carry&
|
||
sbb ecx,ecx ; Save -carry
|
||
add ebp,edi ; zb.awsl.source_current += zb.awsl.dsource_&carry&
|
||
mov zb.awsl.u_current,ebx
|
||
|
||
if WRAP
|
||
mov ebx,dword ptr zb.awsl.u_int_current
|
||
add ebx,zb.awsl.du_int_&carry&
|
||
sub ebx,ecx ; zb.awsl.u_int_current += carry;
|
||
mov dword ptr zb.awsl.u_int_current,ebx
|
||
endif ; WRAP
|
||
|
||
ifidni <BPP>,<2>
|
||
shl ecx,1
|
||
elseifidni <BPP>,<3>
|
||
lea ecx,[ecx+ecx*2]
|
||
elseifidni <BPP>,<4>
|
||
shl ecx,2
|
||
endif ; <BPP>
|
||
|
||
sub ebp,ecx ; zb.awsl.source_current += carry*BPP
|
||
|
||
mov ebx,zb.awsl.v_current
|
||
mov ecx,zb.awsl.dv_&carry&
|
||
add ebx,ecx
|
||
mov zb.awsl.v_current,ebx
|
||
jnc lab2
|
||
|
||
mov edi,zb.awsl.texture_stride
|
||
add ebp,edi
|
||
lab2:
|
||
|
||
mov zb.awsl.source_current,ebp
|
||
endm
|
||
|
||
|
||
|
||
TriangleRenderZ2 macro fn,LIGHT,BPP,BUMP
|
||
|
||
fn proc uses eax ebx ecx edx esi edi ebp
|
||
|
||
outer:
|
||
mov eax,zb.awsl.edge
|
||
mov ebx,[eax].scan_edge.count
|
||
test ebx,ebx
|
||
jz exit
|
||
dec ebx ; zb.awsl.edge->count--
|
||
mov [eax].scan_edge.count,ebx
|
||
|
||
if BUMP
|
||
mov ecx,zb.bump_buffer
|
||
sub ecx,zb.texture_buffer
|
||
mov noffset,ecx
|
||
endif
|
||
|
||
mov edi,zb.awsl.start
|
||
mov ebx,zb.awsl._end
|
||
cmp edi,ebx
|
||
mov eax,zb.awsl.u_current
|
||
mov ebx,zb.awsl.v_current
|
||
|
||
mov al,byte ptr zb.awsl.u_int_current
|
||
|
||
mov ecx,zb.pz.current
|
||
mov zb.pz.currentpix,ecx
|
||
|
||
if LIGHT
|
||
mov ecx,zb.pi.current
|
||
mov zb.pi.currentpix,ecx
|
||
endif ; LIGHT
|
||
|
||
mov ah,byte ptr zb.awsl.u_int_current+1
|
||
|
||
mov esi,zb.awsl.source_current
|
||
mov ebp,zb.awsl.zstart
|
||
|
||
jge scan_back
|
||
|
||
; Forward scan
|
||
loopf:
|
||
mov ecx,zb.awsl._end
|
||
cmp edi,ecx
|
||
jge next
|
||
|
||
; 16 bit z test
|
||
|
||
mov bl,byte ptr zb.pz.currentpix+2
|
||
mov dl,[ebp]
|
||
mov bh,byte ptr zb.pz.currentpix+3
|
||
mov dh,1[ebp]
|
||
cmp dl,bl
|
||
sbb dh,bh
|
||
jb failf ; Skip if pixel failed z test
|
||
|
||
if LIGHT
|
||
|
||
xor ecx,ecx
|
||
mov [ebp],bl ; Store low byte of z
|
||
|
||
mov ch,byte ptr zb.pi.currentpix+2 ; Get lighting index
|
||
mov edx,zb.shade_table
|
||
mov cl,[esi] ; Get texel
|
||
mov 1[ebp],bh ; Store high byte of z
|
||
add edx,ecx
|
||
mov ecx,zb.pz.currentpix
|
||
add ebp,2 ; zptr += 2
|
||
mov bl,[edx] ; Light texel
|
||
mov edx,zb.pz.grad_x ; z += dz
|
||
mov [edi],bl ; Store texel
|
||
|
||
add ecx,edx
|
||
|
||
ifidni <BPP>,<1>
|
||
inc edi ; ptr++
|
||
else ; <BPP>
|
||
add edi,BPP
|
||
endif ; <BPP>
|
||
|
||
mov edx,zb.pi.currentpix
|
||
mov zb.pz.currentpix,ecx
|
||
mov ecx,zb.pi.grad_x ; i += di
|
||
add edx,ecx
|
||
mov zb.pi.currentpix,edx
|
||
|
||
jmp contf
|
||
|
||
failf:
|
||
add ebp,2 ; zptr += 2
|
||
|
||
ifidni <BPP>,<1>
|
||
inc edi ; ptr++
|
||
else ; <BPP>
|
||
add edi,BPP
|
||
endif ; <BPP>
|
||
|
||
mov ecx,zb.pz.currentpix
|
||
mov edx,zb.pz.grad_x ; z += dz
|
||
add ecx,edx
|
||
mov edx,zb.pi.currentpix
|
||
mov zb.pz.currentpix,ecx
|
||
mov ecx,zb.pi.grad_x ; i += di
|
||
add edx,ecx
|
||
mov zb.pi.currentpix,edx
|
||
|
||
elseif BUMP
|
||
|
||
; Bump mapping
|
||
|
||
mov [ebp],bl ; Store low byte of z
|
||
|
||
xor ecx,ecx
|
||
mov cl,[esi] ; Get texel
|
||
mov edx,noffset
|
||
mov dl,[esi+edx] ; Get normal
|
||
and edx,0ffh
|
||
add edx,zb.lighting_table ; Calculate light level from normal
|
||
mov ch,[edx]
|
||
mov edx,zb.shade_table
|
||
mov cl,[edx+ecx] ; Light texel
|
||
mov 1[ebp],bh ; Store high byte of z
|
||
mov [edi],cl
|
||
|
||
mov ecx,zb.pz.currentpix
|
||
add ebp,2 ; zptr += 2
|
||
mov edx,zb.pz.grad_x
|
||
|
||
add ecx,edx ; z += dz
|
||
|
||
ifidni <BPP>,<1>
|
||
inc edi ; ptr++
|
||
else ; <BPP>
|
||
add edi,BPP
|
||
endif ; <BPP>
|
||
|
||
mov zb.pz.currentpix,ecx
|
||
jmp contf
|
||
|
||
failf:
|
||
add ebp,2 ; zptr += 2
|
||
|
||
ifidni <BPP>,<1>
|
||
inc edi ; ptr++
|
||
else ; <BPP>
|
||
add edi,BPP
|
||
endif ; <BPP>
|
||
|
||
mov ecx,zb.pz.currentpix
|
||
mov edx,zb.pz.grad_x ; z += dz
|
||
add ecx,edx
|
||
mov zb.pz.currentpix,ecx
|
||
|
||
else ; LIGHT
|
||
|
||
; No lighting
|
||
|
||
mov [ebp],bl ; Store low byte of z
|
||
|
||
ifidni <BPP>,<1>
|
||
|
||
mov cl,[esi] ; Get texel
|
||
mov 1[ebp],bh ; Store high byte of z
|
||
mov [edi],cl
|
||
|
||
elseifidni <BPP>,<2>
|
||
|
||
mov cl,[esi]
|
||
mov 1[ebp],bh ; Store high byte of z
|
||
mov ch,1[esi]
|
||
mov [edi],cl
|
||
mov 1[edi],ch
|
||
|
||
elseifidni <BPP>,<3>
|
||
|
||
mov cl,[esi] ; Get texel
|
||
mov 1[ebp],bh ; Store high byte of z
|
||
mov [edi],cl
|
||
mov ch,1[esi]
|
||
mov 1[edi],ch ; Store green
|
||
mov cl,2[esi]
|
||
mov 2[edi],cl ; Store red
|
||
|
||
elseifidni <BPP>,<4>
|
||
|
||
mov ecx,[esi]
|
||
mov 1[ebp],bh
|
||
mov [edi],ecx
|
||
|
||
endif ; <BPP>
|
||
|
||
mov ecx,zb.pz.currentpix
|
||
add ebp,2 ; zptr += 2
|
||
mov edx,zb.pz.grad_x
|
||
|
||
add ecx,edx ; z += dz
|
||
|
||
ifidni <BPP>,<1>
|
||
inc edi ; ptr++
|
||
else ; <BPP>
|
||
add edi,BPP
|
||
endif ; <BPP>
|
||
|
||
mov zb.pz.currentpix,ecx
|
||
jmp contf
|
||
|
||
failf:
|
||
add ebp,2 ; zptr += 2
|
||
|
||
ifidni <BPP>,<1>
|
||
inc edi ; ptr++
|
||
else ; <BPP>
|
||
add edi,BPP
|
||
endif ; <BPP>
|
||
|
||
mov ecx,zb.pz.currentpix
|
||
mov edx,zb.pz.grad_x ; z += dz
|
||
add ecx,edx
|
||
mov zb.pz.currentpix,ecx
|
||
|
||
endif ; LIGHT
|
||
|
||
contf:
|
||
|
||
; Redo this with high and low halfwords of du swapped
|
||
|
||
mov ecx,zb.awsl.du
|
||
add eax,ecx ; u += du
|
||
mov ecx,zb.awsl.dsource
|
||
|
||
sbb edx,edx ; edx = -carry
|
||
add esi,ecx
|
||
mov ecx,zb.awsl.du_int
|
||
sub eax,edx ; zb.awsl.du += carry
|
||
|
||
ifidni <BPP>,<2>
|
||
shl edx,1
|
||
elseifidni <BPP>,<3>
|
||
lea edx,[edx+2*edx]
|
||
elseifidni <BPP>,<4>
|
||
shl edx,2
|
||
endif ; <BPP>
|
||
|
||
sub esi,edx ; esi += carry
|
||
add eax,ecx ; u_int += du_int
|
||
|
||
mov ecx,zb.awsl.dv
|
||
mov edx,zb.awsl.texture_stride;
|
||
add ebx,ecx
|
||
jnc nostridef
|
||
|
||
add esi,edx
|
||
|
||
nostridef:
|
||
test ah,ah
|
||
jl nowidthf
|
||
|
||
mov ecx,zb.awsl.texture_width
|
||
add eax,ecx
|
||
|
||
ifidni <BPP>,<1>
|
||
add esi,ecx
|
||
elseifidni <BPP>,<2>
|
||
lea esi,[esi+2*ecx]
|
||
elseifidni <BPP>,<3>
|
||
lea ecx,[ecx+2*ecx]
|
||
add esi,ecx
|
||
elseifidni <BPP>,<4>
|
||
lea esi,[esi+4*ecx]
|
||
endif ; <BPP>
|
||
|
||
nowidthf:
|
||
mov ecx,zb.awsl.texture_start
|
||
cmp esi,ecx ; Have we underrun?
|
||
jge nosizef
|
||
|
||
mov ecx,zb.awsl.texture_size
|
||
add esi,ecx
|
||
|
||
nosizef:
|
||
|
||
jmp loopf
|
||
|
||
scan_back:
|
||
; Backwards scan
|
||
loopb:
|
||
mov ecx,zb.awsl._end
|
||
cmp edi,ecx
|
||
jle next
|
||
|
||
mov ecx,zb.pz.currentpix
|
||
mov edx,zb.pz.grad_x ; z += dz
|
||
sub ecx,edx
|
||
|
||
if LIGHT
|
||
mov edx,zb.pi.currentpix
|
||
endif
|
||
|
||
mov zb.pz.currentpix,ecx
|
||
|
||
if LIGHT
|
||
mov ecx,zb.pi.grad_x ; i += di
|
||
sub edx,ecx
|
||
mov zb.pi.currentpix,edx
|
||
endif
|
||
|
||
; Redo this with high and low halfwords of du swapped
|
||
|
||
mov ecx,zb.awsl.du
|
||
add eax,ecx ; u += du
|
||
mov ecx,zb.awsl.dsource
|
||
|
||
sbb edx,edx ; edx = -carry
|
||
add esi,ecx
|
||
mov ecx,zb.awsl.du_int
|
||
sub eax,edx
|
||
add eax,ecx ; u_int += du_int
|
||
|
||
ifidni <BPP>,<1>
|
||
sub esi,edx
|
||
elseifidni <BPP>,<2>
|
||
shl edx,1
|
||
sub esi,edx
|
||
elseifidni <BPP>,<3>
|
||
lea edx,[edx+edx*2]
|
||
sub esi,edx
|
||
elseifidni <BPP>,<4>
|
||
shl edx,2
|
||
sub esi,edx
|
||
endif
|
||
|
||
mov ecx,zb.awsl.dv
|
||
add ebx,ecx
|
||
jnc nostrideb
|
||
|
||
mov ecx,zb.awsl.texture_stride
|
||
add esi,ecx
|
||
|
||
nostrideb:
|
||
|
||
test ah,ah
|
||
jl nowidthb
|
||
|
||
mov ecx,zb.awsl.texture_width
|
||
add eax,ecx
|
||
|
||
ifidni <BPP>,<1>
|
||
add esi,ecx
|
||
elseifidni <BPP>,<2>
|
||
lea esi,[esi+2*ecx]
|
||
elseifidni <BPP>,<3>
|
||
lea ecx,[ecx+2*ecx]
|
||
add esi,ecx
|
||
elseifidni <BPP>,<4>
|
||
lea esi,[esi+4*ecx]
|
||
endif ; <BPP>
|
||
|
||
nowidthb:
|
||
mov ecx,zb.awsl.texture_start
|
||
cmp esi,ecx
|
||
jge nosizeb
|
||
|
||
mov ecx,zb.awsl.texture_size
|
||
add esi,ecx
|
||
|
||
nosizeb:
|
||
sub ebp,2 ; zptr += 2
|
||
|
||
ifidni <BPP>,<1>
|
||
dec edi ; ptr += 1
|
||
else ; <BPP>
|
||
sub edi,BPP
|
||
endif ; <BPP>
|
||
|
||
mov dl,byte ptr zb.pz.currentpix+2
|
||
mov bl,[ebp]
|
||
mov dh,byte ptr zb.pz.currentpix+3
|
||
mov bh,1[ebp]
|
||
sub bl,dl
|
||
sbb bh,dh
|
||
jb loopb ; Skip if pixel failed z test
|
||
|
||
mov [ebp],dl ; Store low byte of z
|
||
|
||
if LIGHT
|
||
xor ecx,ecx
|
||
endif ; <LIGHT>
|
||
|
||
mov 1[ebp],dh ; Store high byte of z
|
||
|
||
if LIGHT
|
||
mov ch,byte ptr zb.pi.currentpix+2
|
||
mov edx,zb.shade_table
|
||
endif ; <LIGHT>
|
||
|
||
mov cl,[esi] ; Get texel
|
||
|
||
if LIGHT
|
||
mov cl,[ecx+edx] ; Light texel
|
||
endif
|
||
|
||
mov [edi],cl
|
||
|
||
failb:
|
||
jmp loopb
|
||
|
||
next:
|
||
; Per scan line updates
|
||
|
||
assume eax:ptr scan_edge
|
||
mov eax,zb.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,zb.awsl._end
|
||
|
||
adc ebx,ecx ; zb.awsl._end += edge->d_i+carry
|
||
|
||
mov zb.awsl._end,ebx
|
||
|
||
mov ebx,zb.main.f
|
||
mov ecx,zb.main.d_f
|
||
add ebx,ecx
|
||
mov zb.main.f,ebx
|
||
mov ebx,zb.awsl.start
|
||
mov ecx,zb.main.d_i
|
||
mov esi,zb.awsl.zstart
|
||
jnc noscarry
|
||
|
||
; if (carry) ...
|
||
|
||
adc ecx,0
|
||
lea esi,[esi+2*ecx]
|
||
|
||
add ebx,ecx
|
||
|
||
mov zb.awsl.start,ebx
|
||
mov zb.awsl.zstart,esi
|
||
|
||
scan_inc carry,LIGHT,BPP
|
||
|
||
jmp cont
|
||
|
||
; ... else ...
|
||
noscarry:
|
||
|
||
lea esi,[esi+2*ecx]
|
||
|
||
add ebx,ecx
|
||
|
||
mov zb.awsl.start,ebx
|
||
mov zb.awsl.zstart,esi
|
||
|
||
scan_inc nocarry,LIGHT,BPP
|
||
|
||
; ... endif
|
||
|
||
cont:
|
||
mov ebx,dword ptr zb.awsl.u_int_current
|
||
test bh,bh ; Test sign of low halfword
|
||
jl lab1
|
||
|
||
mov ecx,zb.awsl.texture_width
|
||
add ebx,ecx
|
||
mov dword ptr zb.awsl.u_int_current,ebx
|
||
mov ebx,zb.awsl.source_current
|
||
|
||
add ebx,ecx
|
||
|
||
mov zb.awsl.source_current,ebx
|
||
|
||
lab1:
|
||
mov ebx,zb.awsl.source_current
|
||
mov ecx,zb.awsl.texture_start
|
||
cmp ebx,ecx
|
||
jge outer
|
||
|
||
mov ecx,zb.awsl.texture_size
|
||
add ebx,ecx
|
||
mov zb.awsl.source_current,ebx
|
||
|
||
jmp outer
|
||
|
||
exit:
|
||
ret
|
||
|
||
fn endp
|
||
|
||
endm
|
||
|
||
;TriangleRenderZ2 TrapezoidRenderPIZ2TA,0,1,0
|
||
;TriangleRenderZ2 TrapezoidRenderPIZ2TAN,0,1,1
|
||
TriangleRenderZ2 TrapezoidRenderPIZ2TIANT,1,1,0 ; Hawkeye
|
||
;TriangleRenderZ2 TrapezoidRenderPIZ2TA15,0,2,0
|
||
;TriangleRenderZ2 TrapezoidRenderPIZ2TA24,0,3,0
|
||
|
||
|
||
|
||
end
|
||
|