; Real Phong's shading implemented if flat assembler
; by Maciej Guba.
; http://macgub.co.pl
ROUND2 equ 10
real_phong_tri_z:
;----procedure render Phongs shaded triangle with z coord
;----interpolation ( Catmull alghoritm )-----------------
;----I normalize normal vector in every pixel -----------
;------------------in - eax - x1 shl 16 + y1 ------------
;---------------------- ebx - x2 shl 16 + y2 ------------
;---------------------- ecx - x3 shl 16 + y3 ------------
;---------------------- esi - pointer to Z-buffer filled-
;---------------------- with dd float variables--------
;---------------------- edi - pointer to screen buffer---
;---------------------- xmm0 - 1st normal vector --------
;---------------------- xmm1 - 2cond normal vector ------
;---------------------- xmm2 - 3rd normal vector --------
;---------------------- xmm3 - normalized light vector --
;---------------------- xmm4 - lo -> hi z1, z2, z3 coords
;---------------------- as dwords floats ---------------
;---------------------- xmm5 - lo -> hi y_min, y_max, ---
;---------------------- x_min, x_max as dword integers -
;---------------------- stack - no parameters -----------
;--------------------------------------------------------
;----------------- procedure don't save registers !! ----
push ebp
mov ebp,esp
sub esp,512
sub ebp,16
and ebp,0xfffffff0
.1_nv equ [ebp-16]
.2_nv equ [ebp-32]
.3_nv equ [ebp-48]
.l_v equ [ebp-64]
.z3 equ [ebp-72]
.z2 equ [ebp-76]
.z1 equ [ebp-80]
.x1 equ [ebp-82]
.y1 equ [ebp-84]
.x2 equ [ebp-86]
.y2 equ [ebp-88]
.x3 equ [ebp-90]
.y3 equ [ebp-92]
.Zbuf equ [ebp-96]
.x_max equ [ebp-100]
.x_min equ [ebp-104]
.y_max equ [ebp-108]
.y_min equ [ebp-112]
.screen equ [ebp-116]
.dx12 equ [ebp-120]
.dx13 equ [ebp-124]
.dx23 equ [ebp-128]
.dn12 equ [ebp-144]
.dn13 equ [ebp-160]
.dn23 equ [ebp-176]
.dz12 equ [ebp-180]
.dz13 equ [ebp-184]
.dz23 equ [ebp-188]
.cnv1 equ [ebp-208] ; cur normal vectors
.cnv2 equ [ebp-224]
.cz2 equ [ebp-228]
.cz1 equ [ebp-232]
.sort3: ; sort triangle coordinates...
cmp ax,bx
jle .sort1
xchg eax,ebx
shufps xmm4,xmm4,11100001b
movaps xmm6,xmm0
movaps xmm0,xmm1
movaps xmm1,xmm6
.sort1:
cmp bx,cx
jle .sort2
xchg ebx,ecx
shufps xmm4,xmm4,11011000b
movaps xmm6,xmm1
movaps xmm1,xmm2
movaps xmm2,xmm6
jmp .sort3
.sort2:
movaps .z1,xmm4
mov .y1,eax
mov .y2,ebx
mov .y3,ecx
movdqa .y_min,xmm5
if 1 ; check if at last only fragment
packssdw xmm5,xmm5 ; of triangle is in visable area
pshuflw xmm5,xmm5,11011000b
movdqu xmm7,.y3
movdqa xmm6,xmm5
pshufd xmm5,xmm5,0 ; xmm5 lo-hi -> broadcasted y_min, x_min
pshufd xmm6,xmm6,01010101b ;xmm6 -> brd y_max x_max
movdqa xmm4,xmm7
pcmpgtw xmm7,xmm5
pcmpgtw xmm4,xmm6
pxor xmm7,xmm4
pmovmskb eax,xmm7
and eax,0x00aaaaaa
or eax,eax
jz .rpt_loop2_end
end if
movaps .1_nv,xmm0
movaps .2_nv,xmm1
movaps .3_nv,xmm2
movaps .l_v,xmm3
mov .Zbuf,esi
mov .screen,edi
mov bx,.y2 ; calc deltas
sub bx,.y1
jnz .rpt_dx12_make
xorps xmm7,xmm7
mov dword .dx12,0
mov dword .dz12,0
movaps .dn12,xmm7
jmp .rpt_dx12_done
.rpt_dx12_make:
mov ax,.x2
sub ax,.x1
cwde
movsx ebx,bx
shl eax,ROUND2
cdq
idiv ebx
mov .dx12,eax
cvtsi2ss xmm6,ebx
movss xmm5,.z2
subss xmm5,.z1
divss xmm5,xmm6
movss .dz12,xmm5
movaps xmm0,.2_nv
subps xmm0,.1_nv
shufps xmm6,xmm6,0
divps xmm0,xmm6
movaps .dn12,xmm0
.rpt_dx12_done:
mov bx,.y3 ; calc deltas
sub bx,.y1
jnz .rpt_dx13_make
xorps xmm7,xmm7
mov dword .dx13,0
mov dword .dz13,0
movaps .dn13,xmm7
jmp .rpt_dx13_done
.rpt_dx13_make:
mov ax,.x3
sub ax,.x1
cwde
movsx ebx,bx
shl eax,ROUND2
cdq
idiv ebx
mov .dx13,eax
cvtsi2ss xmm6,ebx
movss xmm5,.z3
subss xmm5,.z1
divss xmm5,xmm6
movss .dz13,xmm5
movaps xmm0,.3_nv
subps xmm0,.1_nv
shufps xmm6,xmm6,0
divps xmm0,xmm6
movaps .dn13,xmm0
.rpt_dx13_done:
mov bx,.y3 ; calc deltas
sub bx,.y2
jnz .rpt_dx23_make
xorps xmm7,xmm7
mov dword .dx23,0
mov dword .dz23,0
movaps .dn23,xmm7
jmp .rpt_dx23_done
.rpt_dx23_make:
mov ax,.x3
sub ax,.x2
cwde
movsx ebx,bx
shl eax,ROUND2
cdq
idiv ebx
mov .dx23,eax
cvtsi2ss xmm6,ebx
movss xmm5,.z3
subss xmm5,.z2
divss xmm5,xmm6
movss .dz23,xmm5
movaps xmm0,.3_nv
subps xmm0,.2_nv
shufps xmm6,xmm6,0
divps xmm0,xmm6
movaps .dn23,xmm0
.rpt_dx23_done:
movsx eax,word .x1
shl eax,ROUND2
mov ebx,eax
mov edx,.z1
mov .cz1,edx
mov .cz2,edx
movaps xmm0,.1_nv
movaps .cnv1,xmm0
movaps .cnv2,xmm0
movsx ecx,word .y1
cmp cx,.y2
jge .rpt_loop1_end
.rpt_loop1:
pushad
movaps xmm2,.y_min
movaps xmm0,.cnv1
movaps xmm1,.cnv2
movlps xmm3,.cz1
movaps xmm4,.l_v
sar ebx,ROUND2
sar eax,ROUND2
mov edi,.screen
mov esi,.Zbuf
call real_phong_line_z
popad
movaps xmm0,.cnv1
movaps xmm1,.cnv2
movss xmm2,.cz1
movss xmm3,.cz2
addps xmm0,.dn13
addps xmm1,.dn12
addss xmm2,.dz13
addss xmm3,.dz12
add eax,.dx13
add ebx,.dx12
movaps .cnv1,xmm0
movaps .cnv2,xmm1
movss .cz1,xmm2
movss .cz2,xmm3
add ecx,1
cmp cx,.y2
jl .rpt_loop1
.rpt_loop1_end:
movsx ecx,word .y2
cmp cx,.y3
jge .rpt_loop2_end
movsx ebx,word .x2 ; eax - cur x1
shl ebx,ROUND2 ; ebx - cur x2
push dword .z2
pop dword .cz2
movaps xmm0,.2_nv
movaps .cnv2,xmm0
.rpt_loop2:
pushad
movaps xmm2,.y_min
movaps xmm0,.cnv1
movaps xmm1,.cnv2
movlps xmm3,.cz1
movaps xmm4,.l_v
sar ebx,ROUND2
sar eax,ROUND2
mov edi,.screen
mov esi,.Zbuf
call real_phong_line_z
popad
movaps xmm0,.cnv1
movaps xmm1,.cnv2
movss xmm2,.cz1
movss xmm3,.cz2
addps xmm0,.dn13
addps xmm1,.dn23
addss xmm2,.dz13
addss xmm3,.dz23
add eax,.dx13
add ebx,.dx23
movaps .cnv1,xmm0
movaps .cnv2,xmm1
movss .cz1,xmm2
movss .cz2,xmm3
add ecx,1
cmp cx,.y3
jl .rpt_loop2
.rpt_loop2_end:
add esp,512
pop ebp
ret
real_phong_line_z:
; in:
; xmm0 - normal vector 1
; xmm1 - normal vect 2
; xmm3 - lo -> hi z1, z2 coords as dwords floats
; xmm2 - lo -> hi y_min, y_max, x_min, x_max
; as dword integers
; xmm4 - normalized light vector
; eax - x1
; ebx - x2
; ecx - y
; edi - screen buffer
; esi - z buffer filled with dd floats
push ebp
mov ebp,esp
sub esp,160
sub ebp,16
and ebp,0xfffffff0
.n1 equ [ebp-16]
.n2 equ [ebp-32]
.lv equ [ebp-48]
.lx1 equ [ebp-52]
.lx2 equ [ebp-56]
.z2 equ [ebp-60]
.z1 equ [ebp-64]
.screen equ [ebp-68]
.zbuff equ [ebp-72]
.x_max equ [ebp-74]
.x_min equ [ebp-76]
.y_max equ [ebp-78]
.y_min equ [ebp-80]
.dn equ [ebp-96]
.dz equ [ebp-100]
.y equ [ebp-104]
.cnv equ [ebp-128]
mov .y,ecx
packssdw xmm2,xmm2
movq .y_min,xmm2
cmp cx,.y_min
jl .end_rp_line
cmp cx,.y_max
jge .end_rp_line ;
cmp eax,ebx
je .end_rp_line
jl @f
xchg eax,ebx
movaps xmm7,xmm0
movaps xmm0,xmm1
movaps xmm1,xmm7
shufps xmm3,xmm3,11100001b
@@:
cmp ax,.x_max
jge .end_rp_line
cmp bx,.x_min
jle .end_rp_line
movaps .lv,xmm4
movaps .n1,xmm0
movaps .n2,xmm1
mov .lx1,eax
mov .lx2,ebx
movlps .z1,xmm3
sub ebx,eax
cvtsi2ss xmm7,ebx
shufps xmm7,xmm7,0
subps xmm1,xmm0
divps xmm1,xmm7
movaps .dn,xmm1
psrldq xmm3,4
subss xmm3,.z1
divss xmm3,xmm7
movss .dz,xmm3
mov ebx,.lx1
cmp bx,.x_min ; clipping on function4
jge @f
movzx eax,word .x_min
sub eax,ebx
cvtsi2ss xmm7,eax
shufps xmm7,xmm7,0
mulss xmm3,xmm7
mulps xmm1,xmm7
addss xmm3,.z1
addps xmm1,.n1
movsx eax,word .x_min
movss .z1,xmm3
movaps .n1,xmm1
mov dword .lx1,eax
@@:
movzx eax,word .x_max
cmp .lx2,eax
jl @f
mov .lx2,eax
@@:
movzx eax,word[size_x_var]
mul dword .y
; mov edx,.x1
add eax,.lx1
shl eax,2
add edi,eax
add esi,eax
mov ecx,.lx2
sub ecx,.lx1
movaps xmm0,.n1
movss xmm2,.z1
.ddraw:
movss xmm7,xmm2
cmpnltss xmm7,dword[esi]
movd eax,xmm7
or eax,eax
jnz .skip
movss [esi],xmm2
movaps xmm7,xmm0
mulps xmm7,xmm7 ; normalize
haddps xmm7,xmm7
haddps xmm7,xmm7
rsqrtps xmm7,xmm7
mulps xmm7,xmm0
movaps .cnv,xmm7
mov edx,lights_aligned ; lights - global variable
xorps xmm1,xmm1 ; instead global can be used .lv - light vect.
@@:
movaps xmm6,[edx+16]
movaps xmm5,[edx]
movaps xmm3,[edx+48]
andps xmm5,[zero_hgst_dd] ; global
mulps xmm5,.cnv ;.lv ; last dword should be zeroed
haddps xmm5,xmm5
haddps xmm5,xmm5
; mulps xmm5,[env_const2]
; maxps xmm5,[dot_min]
; minps xmm5,[dot_max]
movaps xmm7,xmm5
; mulps xmm7,[env_const2]
; mulps xmm7,[env_const2]
; maxps xmm7,[dot_min]
; minps xmm7,[dot_max]
mulps xmm7,xmm7
mulps xmm7,xmm7
mulps xmm5,xmm6
mulps xmm7,xmm7
mulps xmm7,xmm3
addps xmm5,xmm7
minps xmm5,[mask_255f] ; global
maxps xmm1,xmm5
; movq xmm3,[edx+20] ; minimal color
; punpcklwd xmm3,[minimum0]
; cvtdq2ps xmm3,xmm3
; maxps xmm1,xmm3
add edx,64
cmp edx,lights_aligned_end ; global
jnz @b
cvtps2dq xmm1,xmm1
packssdw xmm1,xmm1
packuswb xmm1,xmm1
movd [edi],xmm1
.skip:
add edi,4
add esi,4
addps xmm0,.dn
addss xmm2,.dz
sub ecx,1
jnz .ddraw
.end_rp_line:
add esp,160
pop ebp
ret