; 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 align 16 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 align 16 .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