; Ray casted shadows
; by Maciej Guba.
; http://macgub.co.pl
ROUND2 equ 10
ray_shad:
;--- Procedure render triangle with ray casted shadow ---
;--- effect. Calc intersection with all triangles in ----
;--- everypixel. Its not real time process, especially --
;--- when many triangles are computed. ------------------
;------in - eax - x1 shl 16 + y1 ------------------------
;---------- ebx - x2 shl 16 + y2 ------------------------
;---------- ecx - x3 shl 16 + y3 ------------------------
;---------- edx - ptr to fur coords struct --------------
;---------- esi - pointer to stencil / Z-buffer, filled -
;-------------- with dword float variables, it masks --
;-------------- 'Z' position (coord) of every front ---
;-------------- pixel. --------------------------------
;---------- edi - pointer to screen buffer --------------
;---------- xmm0 - 1st normal vector --------------------
;---------- xmm1 - 2cond normal vector ------------------
;---------- xmm2 - 3rd normal vector --------------------
;---------- xmm3 - --------------------------------------
;---------- xmm4 - lo -> hi z1, z2, z3 coords -----------
;--------------- as dwords floats ---------------------
;---------- xmm5 - lo -> hi y_min, y_max, x_min, x_max --
;--------------- as dword integers --------------------
;-----------mm7 - current triangle index ---------------
;---------------------- stack - no parameters -----------
;--------------------------------------------------------
;----------------- procedure don't save registers !! ----
push ebp
mov ebp,esp
sub esp,1024
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] ; current normal vectors
.cnv2 equ [ebp-240]
.cz2 equ [ebp-244]
.cz1 equ [ebp-248]
.tri_no equ [ebp-252]
.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
movd .tri_no,mm7
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
rcpss xmm6,xmm6
subss xmm5,.z1
mulss xmm5,xmm6
movss .dz12,xmm5
shufps xmm6,xmm6,0
movaps xmm0,.2_nv
subps xmm0,.1_nv
mulps xmm0,xmm6
movaps .dn12,xmm0
; subps xmm3,xmm0
; mulps xmm3,xmm6
.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
rcpss xmm6,xmm6
subss xmm5,.z1
mulss xmm5,xmm6
movss .dz13,xmm5
movaps xmm0,.3_nv
subps xmm0,.1_nv
shufps xmm6,xmm6,0
mulps xmm0,xmm6
movaps .dn13,xmm0
; mulps xmm0,xmm6
.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
rcpss xmm6,xmm6
subss xmm5,.z2
mulss xmm5,xmm6
movss .dz23,xmm5
movaps xmm0,.3_nv
subps xmm0,.2_nv
shufps xmm6,xmm6,0
mulps xmm0,xmm6
movaps .dn23,xmm0
; mulps xmm0,xmm6
.rpt_dx23_done:
movsx eax,word .x1
shl eax,ROUND2
mov ebx,eax
mov ecx,.z1
mov .cz1,ecx
mov .cz2,ecx
movaps xmm0,.1_nv
movaps .cnv1,xmm0
movaps .cnv2,xmm0
mov edi,.screen
mov esi,.Zbuf
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
movd mm7,.tri_no
call ray_shd_l
popad
movaps xmm0,.cnv1
movaps xmm1,.cnv2
; fur x,y
movss xmm2,.cz1
movss xmm3,.cz2
shufps xmm4,xmm4,01001110b
addps xmm0,.dn13
addps xmm1,.dn12
addss xmm2,.dz13
addss xmm3,.dz12
add eax,.dx13
add ebx,.dx12
shufps xmm4,xmm4,01001110b
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
mov edi,.screen
mov esi,.Zbuf
.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
movd mm7,.tri_no
call ray_shd_l
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
addps xmm4,xmm6
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,1024
pop ebp
ret
align 16
ray_shd_l:
; 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 - ----
; mm7 - current triangle index
; eax - x1
; ebx - x2
; ecx - y
; edx - -----
; edi - screen buffer
; esi - z buffer / stencil buffer filled with dd floats
push ebp
mov ebp,esp
sub esp,320
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]
; .cur_tri equ [ebp-108]
.cnv equ [ebp-128]
.Rlen equ [ebp-128-16]
.r1 equ [ebp-128-32]
.vect_t equ [ebp-128-48]
.cur_tri equ [ebp-128-64]
; .p3t equ [ebp-128-80]
.nray equ [ebp-128-96]
.final_col equ [ebp-128-112]
.aabb_mask equ dword[ebp-128-112-4]
mov .y,ecx
movdqa xmm4,xmm2
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
@@:
movd .cur_tri,mm7
cmp ax,.x_max
jge .end_rp_line
cmp bx,.x_min
jle .end_rp_line
; movaps .lv,xmm4
andps xmm0,[zero_hgst_dd]
andps xmm1,[zero_hgst_dd]
movaps .n1,xmm0
movaps .n2,xmm1
mov .lx1,eax
mov .lx2,ebx
movlps .z1,xmm3
sub ebx,eax
cvtsi2ss xmm7,ebx
rcpss xmm7,xmm7
shufps xmm7,xmm7,0
subps xmm1,xmm0
mulps xmm1,xmm7
movaps .dn,xmm1
shufps xmm3,xmm3,11111001b
subss xmm3,.z1
mulss xmm3,xmm7
movss .dz,xmm3
subps xmm6,xmm5
mulps xmm6,xmm7
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
mulps xmm6,xmm7
addss xmm3,.z1
addps xmm1,.n1
addps xmm6,xmm5
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[xres_var]
mul dword .y
add eax,.lx1
mov .zbuff,esi
mov .screen,edi
shl eax,2
add edi,eax
add esi,eax
mov ecx,.lx2
sub ecx,.lx1
movd xmm0,[vect_x]
punpcklwd xmm0,[the_zero]
cvtdq2ps xmm0,xmm0
movaps .vect_t,xmm0
.ddraw:
xorps xmm0,xmm0
movss xmm2,.z1
movss xmm5,.z1
movaps .final_col,xmm0
addss xmm2,[f1]
subss xmm5,[f1]
cmpnltss xmm2,dword[esi]
cmpnltss xmm5,dword[esi]
pxor xmm2,xmm5
movd eax,xmm2
or eax,eax
jz .skips
movaps xmm7,.n1
andps xmm7,[zero_hgst_dd]
mulps xmm7,xmm7 ; normalize
haddps xmm7,xmm7
haddps xmm7,xmm7
rsqrtps xmm7,xmm7
mulps xmm7,.n1
movaps .cnv,xmm7
mov ebx,point_light_coords
mov edx,lights_aligned
xor eax,eax
.nx_light:
pushad
cvtsi2ss xmm0,.lx1
cvtsi2ss xmm1,.y
movss xmm2,.z1
movlhps xmm0,xmm1
shufps xmm0,xmm2,11001000b
subps xmm0,[ebx] ; xmm0 - ray end, -> current vertex
movaps xmm3,[ebx]
andps xmm0,[zero_hgst_dd]
movaps xmm1,xmm0
mulps xmm0,xmm0
haddps xmm0,xmm0
haddps xmm0,xmm0
sqrtps xmm0,xmm0
movss .Rlen,xmm0
rcpps xmm0,xmm0
mulps xmm0,xmm1 ; xmm0 - normalized ray vector
andps xmm0,[zero_hgst_dd]
movaps .nray,xmm0
movaps .r1,xmm3 ; ray orgin
if 0
movaps xmm1,xmm3
call calc_bounding_box
mov .aabb_mask,eax
end if
mov edi,[triangles_ptr]
xor ecx,ecx
.nx_tri: ; next triangle
cmp ecx,.cur_tri ; prevent self shadowing
je .skipp
if 0
mov edi,ecx
imul edi,[i12]
add edi,[triangles_ptr]
mov eax,[edi]
mov ebx,[edi+4]
mov edx,[edi+8]
imul eax,[i12]
imul ebx,[i12]
imul edx,[i12]
add eax,[points_ptr]
add ebx,[points_ptr]
add edx,[points_ptr]
movups xmm2,[eax]
movups xmm3,[ebx]
movups xmm4,[edx]
andps xmm2,[sign_mask]
andps xmm3,[sign_mask]
andps xmm4,[sign_mask]
movmskps ebx,xmm4
cmpeqps xmm2,xmm3
cmpeqps xmm3,xmm4
andps xmm2,xmm3
movmskps eax,xmm2
and eax,111b
and ebx,111b
cmp eax,111b
jne @f
bt .aabb_mask,ebx
jnc .skipp
@@:
end if
mov edi,ecx
imul edi,[i12]
add edi,[triangles_ptr]
mov eax,[edi]
mov ebx,[edi+4]
mov edx,[edi+8]
imul eax,[i12]
imul ebx,[i12]
imul edx,[i12]
add eax,[points_rotated_ptr]
add ebx,[points_rotated_ptr]
add edx,[points_rotated_ptr]
movups xmm2,[eax]
movups xmm3,[ebx]
movups xmm4,[edx]
addps xmm2,.vect_t
addps xmm3,.vect_t
addps xmm4,.vect_t
;intersect_tri: procs header
; in:
; xmm0 - ray direction ; should be normalized
; xmm1 - ray orgin
; xmm2 - tri vert1
; xmm3 - tri vert2
; xmm4 - tri vert3
; if eax = 1 - intersction with edge
; xmm6 - edge lenght
; if eax = 0 - intersect with ray (classic)
; out:
; eax = 1 - intersection occured
; xmm0 - float lo -> hi = t, v, u, ...
movss xmm6,.Rlen
movaps xmm0,.nray
movaps xmm1,.r1
subss xmm6,[the_one]
mov eax,1
push ecx
call intersect_tri
pop ecx
cmp eax,1
je .inter
.skipp:
.skp:
inc ecx
cmp ecx,[triangles_count_var]
jnz .nx_tri
; jz .do_process
; comiss xmm0,.Rlen
; jl .inter
popad
.do_process:
movaps xmm5,.nray ;[edx]
andps xmm5,[zero_hgst_dd] ; global
mulps xmm5,.cnv ;.lv ; last dword should be zeroed
; andps xmm5,[sign_z] ; global
haddps xmm5,xmm5
haddps xmm5,xmm5
andps xmm5,[abs_mask] ; global
movaps xmm7,xmm5
mulps xmm7,xmm7
mulps xmm7,xmm7
mulps xmm5,[edx+16]
mulps xmm7,xmm7
mulps xmm7,xmm7
mulps xmm7,[edx+48]
addps xmm5,xmm7
minps xmm5,[mask_255f] ; global
maxps xmm5,.final_col ; addps maxps
movaps .final_col,xmm5
jmp .nx_loop
.inter:
popad
.nx_loop:
; add edx,64 ; unncomment to achive 3 lights
; add ebx,16
; cmp edx,lights_aligned_end ; global
; jnz .nx_light
movaps xmm1,.final_col
cvtps2dq xmm1,xmm1
packssdw xmm1,xmm1
packuswb xmm1,xmm1
movd [edi],xmm1
.skips:
movaps xmm0,.n1
movss xmm2,.z1
add edi,4
add esi,4
add dword .lx1,1
addps xmm0,.dn
addss xmm2,.dz
movaps .n1,xmm0
movss .z1,xmm2
dec ecx
jnz .ddraw
.end_rp_line:
add esp,320
pop ebp
ret