; 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 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] .startx 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 .startx,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 ; mov eax,.lx1 ; cmp eax,.startx ; je @f ; prevent artifact borders on tri ; cmp eax,.lx2 ; NOT work as I want !! ; je @f 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