;
; d_draw.asm
; $Id: d_draw.asm,v 1.2 2007/06/16 09:21:55 sezero Exp $
; x86 assembly-language horizontal 8-bpp span-drawing code.
;

%idefine offset
 extern d_zistepu
 extern d_pzbuffer
 extern d_zistepv
 extern d_zrowbytes
 extern d_ziorigin
 extern r_turb_s
 extern r_turb_t
 extern r_turb_pdest
 extern r_turb_spancount
 extern r_turb_turb
 extern r_turb_pbase
 extern r_turb_sstep
 extern r_turb_tstep
 extern r_bmodelactive
 extern d_sdivzstepu
 extern d_tdivzstepu
 extern d_sdivzstepv
 extern d_tdivzstepv
 extern d_sdivzorigin
 extern d_tdivzorigin
 extern sadjust
 extern tadjust
 extern bbextents
 extern bbextentt
 extern cacheblock
 extern d_viewbuffer
 extern cachewidth
 extern d_pzbuffer
 extern d_zrowbytes
 extern d_zwidth
 extern d_scantable
 extern r_lightptr
 extern r_numvblocks
 extern prowdestbase
 extern pbasesource
 extern r_lightwidth
 extern lightright
 extern lightrightstep
 extern lightdeltastep
 extern lightdelta
 extern lightright
 extern lightdelta
 extern sourcetstep
 extern surfrowbytes
 extern lightrightstep
 extern lightdeltastep
 extern r_sourcemax
 extern r_stepback
 extern colormap
 extern blocksize
 extern sourcesstep
 extern lightleft
 extern blockdivshift
 extern blockdivmask
 extern lightleftstep
 extern r_origin
 extern r_ppn
 extern r_pup
 extern r_pright
 extern ycenter
 extern xcenter
 extern d_vrectbottom_particle
 extern d_vrectright_particle
 extern d_vrecty
 extern d_vrectx
 extern d_pix_shift
 extern d_pix_min
 extern d_pix_max
 extern d_y_aspect_shift
 extern screenwidth
 extern r_leftclipped
 extern r_leftenter
 extern r_rightclipped
 extern r_rightenter
 extern modelorg
 extern xscale
 extern r_refdef
 extern yscale
 extern r_leftexit
 extern r_rightexit
 extern r_lastvertvalid
 extern cacheoffset
 extern newedges
 extern removeedges
 extern r_pedge
 extern r_framecount
 extern r_u1
 extern r_emitted
 extern edge_p
 extern surface_p
 extern surfaces
 extern r_lzi1
 extern r_v1
 extern r_ceilv1
 extern r_nearzi
 extern r_nearzionly
 extern edge_aftertail
 extern edge_tail
 extern current_iv
 extern edge_head_u_shift20
 extern span_p
 extern edge_head
 extern fv
 extern edge_tail_u_shift20
 extern r_apverts
 extern r_anumverts
 extern aliastransform
 extern r_avertexnormals
 extern r_plightvec
 extern r_ambientlight
 extern r_shadelight
 extern aliasxcenter
 extern aliasycenter
 extern a_sstepxfrac
 extern r_affinetridesc
 extern acolormap
 extern d_pcolormap
 extern r_affinetridesc
 extern d_sfrac
 extern d_ptex
 extern d_pedgespanpackage
 extern d_tfrac
 extern d_light
 extern d_zi
 extern d_pdest
 extern d_pz
 extern d_aspancount
 extern erroradjustup
 extern errorterm
 extern d_xdenom
 extern r_p0
 extern r_p1
 extern r_p2
 extern a_tstepxfrac
 extern r_sstepx
 extern r_tstepx
 extern a_ststepxwhole
 extern zspantable
 extern skintable
 extern r_zistepx
 extern erroradjustdown
 extern d_countextrastep
 extern ubasestep
 extern a_ststepxwhole
 extern a_tstepxfrac
 extern r_lstepx
 extern a_spans
 extern erroradjustdown
 extern d_pdestextrastep
 extern d_pzextrastep
 extern d_sfracextrastep
 extern d_ptexextrastep
 extern d_countextrastep
 extern d_tfracextrastep
 extern d_lightextrastep
 extern d_ziextrastep
 extern d_pdestbasestep
 extern d_pzbasestep
 extern d_sfracbasestep
 extern d_ptexbasestep
 extern ubasestep
 extern d_tfracbasestep
 extern d_lightbasestep
 extern d_zibasestep
 extern zspantable
 extern r_lstepy
 extern r_sstepy
 extern r_tstepy
 extern r_zistepy
 extern D_PolysetSetEdgeTable
 extern D_RasterizeAliasPolySmooth
 extern float_point5
 extern Float2ToThe31nd
 extern izistep
 extern izi
 extern FloatMinus2ToThe31nd
 extern float_1
 extern float_particle_z_clip
 extern float_minus_1
 extern float_0
 extern fp_16
 extern fp_64k
 extern fp_1m
 extern fp_1m_minus_1
 extern fp_8
 extern entryvec_table
 extern advancetable
 extern sstep
 extern tstep
 extern pspantemp
 extern counttemp
 extern jumptemp
 extern reciprocal_table
 extern DP_Count
 extern DP_u
 extern DP_v
 extern DP_32768
 extern DP_Color
 extern DP_Pix
 extern DP_EntryTable
 extern pbase
 extern s
 extern t
 extern sfracf
 extern tfracf
 extern snext
 extern tnext
 extern spancountminus1
 extern zi16stepu
 extern sdivz16stepu
 extern tdivz16stepu
 extern zi8stepu
 extern sdivz8stepu
 extern tdivz8stepu
 extern reciprocal_table_16
 extern entryvec_table_16
 extern ceil_cw
 extern single_cw
 extern fp_64kx64k
 extern pz
 extern spr8entryvec_table
 extern snd_scaletable
 extern paintbuffer
 extern snd_linear_count
 extern snd_p
 extern snd_vol
 extern snd_out
 extern vright
 extern vup
 extern vpn
 extern BOPS_Error
 extern scanList
 extern ZScanCount
SEGMENT .text
LClampHigh0:
 mov esi, dword [bbextents]
 jmp LClampReentry0
LClampHighOrLow0:
 jg LClampHigh0
 xor esi,esi
 jmp LClampReentry0
LClampHigh1:
 mov edx, dword [bbextentt]
 jmp LClampReentry1
LClampHighOrLow1:
 jg LClampHigh1
 xor edx,edx
 jmp LClampReentry1
LClampLow2:
 mov ebp,2048
 jmp LClampReentry2
LClampHigh2:
 mov ebp, dword [bbextents]
 jmp LClampReentry2
LClampLow3:
 mov ecx,2048
 jmp LClampReentry3
LClampHigh3:
 mov ecx, dword [bbextentt]
 jmp LClampReentry3
LClampLow4:
 mov eax,2048
 jmp LClampReentry4
LClampHigh4:
 mov eax, dword [bbextents]
 jmp LClampReentry4
LClampLow5:
 mov ebx,2048
 jmp LClampReentry5
LClampHigh5:
 mov ebx, dword [bbextentt]
 jmp LClampReentry5
 ALIGN 4
 global D_DrawSpans8
D_DrawSpans8:
 push ebp
 push edi
 push esi
 push ebx
 fld  dword [d_sdivzstepu]
 fmul  dword [fp_8]
 mov edx, dword [cacheblock]
 fld  dword [d_tdivzstepu]
 fmul  dword [fp_8]
 mov ebx, dword [4+16+esp]
 fld  dword [d_zistepu]
 fmul  dword [fp_8]
 mov  dword [pbase],edx
 fstp  dword [zi8stepu]
 fstp  dword [tdivz8stepu]
 fstp  dword [sdivz8stepu]
LSpanLoop:
 fild  dword [4+ebx]
 fild  dword [0+ebx]
 fld st1
 fmul  dword [d_sdivzstepv]
 fld st1
 fmul  dword [d_sdivzstepu]
 fld st2
 fmul  dword [d_tdivzstepu]
 fxch st1
 faddp st2,st0
 fxch st1
 fld st3
 fmul  dword [d_tdivzstepv]
 fxch st1
 fadd  dword [d_sdivzorigin]
 fxch st4
 fmul  dword [d_zistepv]
 fxch st1
 faddp st2,st0
 fxch st2
 fmul  dword [d_zistepu]
 fxch st1
 fadd  dword [d_tdivzorigin]
 fxch st2
 faddp st1,st0
 fld  dword [fp_64k]
 fxch st1
 fadd  dword [d_ziorigin]
 fdiv st1,st0
 mov ecx, dword [d_viewbuffer]
 mov eax, dword [4+ebx]
 mov  dword [pspantemp],ebx
 mov edx, dword [tadjust]
 mov esi, dword [sadjust]
 mov edi, dword [d_scantable+eax*4]
 add edi,ecx
 mov ecx, dword [0+ebx]
 add edi,ecx
 mov ecx, dword [8+ebx]
 cmp ecx,8
 ja LSetupNotLast1
 dec ecx
 jz LCleanup1
 mov  dword [spancountminus1],ecx
 fxch st1
 fld st0
 fmul st0,st4
 fxch st1
 fmul st0,st3
 fxch st1
 fistp  dword [s]
 fistp  dword [t]
 fild  dword [spancountminus1]
 fld  dword [d_tdivzstepu]
 fld  dword [d_zistepu]
 fmul st0,st2
 fxch st1
 fmul st0,st2
 fxch st2
 fmul  dword [d_sdivzstepu]
 fxch st1
 faddp st3,st0
 fxch st1
 faddp st3,st0
 faddp st3,st0
 fld  dword [fp_64k]
 fdiv st0,st1
 jmp LFDIVInFlight1
LCleanup1:
 fxch st1
 fld st0
 fmul st0,st4
 fxch st1
 fmul st0,st3
 fxch st1
 fistp  dword [s]
 fistp  dword [t]
 jmp LFDIVInFlight1
 ALIGN 4
LSetupNotLast1:
 fxch st1
 fld st0
 fmul st0,st4
 fxch st1
 fmul st0,st3
 fxch st1
 fistp  dword [s]
 fistp  dword [t]
 fadd  dword [zi8stepu]
 fxch st2
 fadd  dword [sdivz8stepu]
 fxch st2
 fld  dword [tdivz8stepu]
 faddp st2,st0
 fld  dword [fp_64k]
 fdiv st0,st1
LFDIVInFlight1:
 add esi, dword [s]
 add edx, dword [t]
 mov ebx, dword [bbextents]
 mov ebp, dword [bbextentt]
 cmp esi,ebx
 ja near LClampHighOrLow0
LClampReentry0:
 mov  dword [s],esi
 mov ebx, dword [pbase]
 shl esi,16
 cmp edx,ebp
 mov  dword [sfracf],esi
 ja near LClampHighOrLow1
LClampReentry1:
 mov  dword [t],edx
 mov esi, dword [s]
 shl edx,16
 mov eax, dword [t]
 sar esi,16
 mov  dword [tfracf],edx
 sar eax,16
 mov edx, dword [cachewidth]
 imul eax,edx
 add esi,ebx
 add esi,eax
 cmp ecx,8
 jna near LLastSegment
LNotLastSegment:
 fld st0
 fmul st0,st4
 fxch st1
 fmul st0,st3
 fxch st1
 fistp  dword [snext]
 fistp  dword [tnext]
 mov eax, dword [snext]
 mov edx, dword [tnext]
 mov bl, byte [esi]
 sub ecx,8
 mov ebp, dword [sadjust]
 mov  dword [counttemp],ecx
 mov ecx, dword [tadjust]
 mov  byte [edi],bl
 add ebp,eax
 add ecx,edx
 mov eax, dword [bbextents]
 mov edx, dword [bbextentt]
 cmp ebp,2048
 jl near LClampLow2
 cmp ebp,eax
 ja near LClampHigh2
LClampReentry2:
 cmp ecx,2048
 jl near LClampLow3
 cmp ecx,edx
 ja near LClampHigh3
LClampReentry3:
 mov  dword [snext],ebp
 mov  dword [tnext],ecx
 sub ebp, dword [s]
 sub ecx, dword [t]
 mov eax,ecx
 mov edx,ebp
 sar eax,19
 jz LZero
 sar edx,19
 mov ebx, dword [cachewidth]
 imul eax,ebx
 jmp LSetUp1
LZero:
 sar edx,19
 mov ebx, dword [cachewidth]
LSetUp1:
 add eax,edx
 mov edx, dword [tfracf]
 mov  dword [advancetable+4],eax
 add eax,ebx
 shl ebp,13
 mov ebx, dword [sfracf]
 shl ecx,13
 mov  dword [advancetable],eax
 mov  dword [tstep],ecx
 add edx,ecx
 sbb ecx,ecx
 add ebx,ebp
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
 sbb ecx,ecx
 mov al, byte [esi]
 add ebx,ebp
 mov  byte [1+edi],al
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
 sbb ecx,ecx
 add ebx,ebp
 mov al, byte [esi]
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
 sbb ecx,ecx
 mov  byte [2+edi],al
 add ebx,ebp
 mov al, byte [esi]
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
 sbb ecx,ecx
 mov  byte [3+edi],al
 add ebx,ebp
 mov al, byte [esi]
 adc esi, dword [advancetable+4+ecx*4]
 mov ecx, dword [counttemp]
 cmp ecx,8
 ja LSetupNotLast2
 dec ecx
 jz LFDIVInFlight2
 mov  dword [spancountminus1],ecx
 fild  dword [spancountminus1]
 fld  dword [d_zistepu]
 fmul st0,st1
 fld  dword [d_tdivzstepu]
 fmul st0,st2
 fxch st1
 faddp st3,st0
 fxch st1
 fmul  dword [d_sdivzstepu]
 fxch st1
 faddp st3,st0
 fld  dword [fp_64k]
 fxch st1
 faddp st4,st0
 fdiv st0,st1
 jmp LFDIVInFlight2
 ALIGN 4
LSetupNotLast2:
 fadd  dword [zi8stepu]
 fxch st2
 fadd  dword [sdivz8stepu]
 fxch st2
 fld  dword [tdivz8stepu]
 faddp st2,st0
 fld  dword [fp_64k]
 fdiv st0,st1
LFDIVInFlight2:
 mov  dword [counttemp],ecx
 add edx, dword [tstep]
 sbb ecx,ecx
 mov  byte [4+edi],al
 add ebx,ebp
 mov al, byte [esi]
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
 sbb ecx,ecx
 mov  byte [5+edi],al
 add ebx,ebp
 mov al, byte [esi]
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
 sbb ecx,ecx
 mov  byte [6+edi],al
 add ebx,ebp
 mov al, byte [esi]
 adc esi, dword [advancetable+4+ecx*4]
 add edi,8
 mov  dword [tfracf],edx
 mov edx, dword [snext]
 mov  dword [sfracf],ebx
 mov ebx, dword [tnext]
 mov  dword [s],edx
 mov  dword [t],ebx
 mov ecx, dword [counttemp]
 cmp ecx,8
 mov  byte [-1+edi],al
 ja near LNotLastSegment
LLastSegment:
 test ecx,ecx
 jz near LNoSteps
 fld st0
 fmul st0,st4
 fxch st1
 fmul st0,st3
 fxch st1
 fistp  dword [snext]
 fistp  dword [tnext]
 mov al, byte [esi]
 mov ebx, dword [tadjust]
 mov  byte [edi],al
 mov eax, dword [sadjust]
 add eax, dword [snext]
 add ebx, dword [tnext]
 mov ebp, dword [bbextents]
 mov edx, dword [bbextentt]
 cmp eax,2048
 jl near LClampLow4
 cmp eax,ebp
 ja near LClampHigh4
LClampReentry4:
 mov  dword [snext],eax
 cmp ebx,2048
 jl near LClampLow5
 cmp ebx,edx
 ja near LClampHigh5
LClampReentry5:
 cmp ecx,1
 je near LOnlyOneStep
 sub eax, dword [s]
 sub ebx, dword [t]
 add eax,eax
 add ebx,ebx
 imul  dword [reciprocal_table-8+ecx*4]
 mov ebp,edx
 mov eax,ebx
 imul  dword [reciprocal_table-8+ecx*4]
LSetEntryvec:
 mov ebx, dword [entryvec_table+ecx*4]
 mov eax,edx
 mov  dword [jumptemp],ebx
 mov ecx,ebp
 sar edx,16
 mov ebx, dword [cachewidth]
 sar ecx,16
 imul edx,ebx
 add edx,ecx
 mov ecx, dword [tfracf]
 mov  dword [advancetable+4],edx
 add edx,ebx
 shl ebp,16
 mov ebx, dword [sfracf]
 shl eax,16
 mov  dword [advancetable],edx
 mov  dword [tstep],eax
 mov edx,ecx
 add edx,eax
 sbb ecx,ecx
 add ebx,ebp
 adc esi, dword [advancetable+4+ecx*4]
 jmp dword[jumptemp]
LNoSteps:
 mov al, byte [esi]
 sub edi,7
 jmp LEndSpan
LOnlyOneStep:
 sub eax, dword [s]
 sub ebx, dword [t]
 mov ebp,eax
 mov edx,ebx
 jmp LSetEntryvec
 global Entry2_8
Entry2_8:
 sub edi,6
 mov al, byte [esi]
 jmp LLEntry2_8
 global Entry3_8
Entry3_8:
 sub edi,5
 add edx,eax
 mov al, byte [esi]
 sbb ecx,ecx
 add ebx,ebp
 adc esi, dword [advancetable+4+ecx*4]
 jmp LLEntry3_8
 global Entry4_8
Entry4_8:
 sub edi,4
 add edx,eax
 mov al, byte [esi]
 sbb ecx,ecx
 add ebx,ebp
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
 jmp LLEntry4_8
 global Entry5_8
Entry5_8:
 sub edi,3
 add edx,eax
 mov al, byte [esi]
 sbb ecx,ecx
 add ebx,ebp
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
 jmp LLEntry5_8
 global Entry6_8
Entry6_8:
 sub edi,2
 add edx,eax
 mov al, byte [esi]
 sbb ecx,ecx
 add ebx,ebp
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
 jmp LLEntry6_8
 global Entry7_8
Entry7_8:
 dec edi
 add edx,eax
 mov al, byte [esi]
 sbb ecx,ecx
 add ebx,ebp
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
 jmp LLEntry7_8
 global Entry8_8
Entry8_8:
 add edx,eax
 mov al, byte [esi]
 sbb ecx,ecx
 add ebx,ebp
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
 sbb ecx,ecx
 mov  byte [1+edi],al
 add ebx,ebp
 mov al, byte [esi]
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
LLEntry7_8:
 sbb ecx,ecx
 mov  byte [2+edi],al
 add ebx,ebp
 mov al, byte [esi]
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
LLEntry6_8:
 sbb ecx,ecx
 mov  byte [3+edi],al
 add ebx,ebp
 mov al, byte [esi]
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
LLEntry5_8:
 sbb ecx,ecx
 mov  byte [4+edi],al
 add ebx,ebp
 mov al, byte [esi]
 adc esi, dword [advancetable+4+ecx*4]
 add edx, dword [tstep]
LLEntry4_8:
 sbb ecx,ecx
 mov  byte [5+edi],al
 add ebx,ebp
 mov al, byte [esi]
 adc esi, dword [advancetable+4+ecx*4]
LLEntry3_8:
 mov  byte [6+edi],al
 mov al, byte [esi]
LLEntry2_8:
LEndSpan:
 fstp st0
 fstp st0
 fstp st0
 mov ebx, dword [pspantemp]
 mov ebx, dword [12+ebx]
 test ebx,ebx
 mov  byte [7+edi],al
 jnz near LSpanLoop
 pop ebx
 pop esi
 pop edi
 pop ebp
 ret

LClamp:
 mov edx,040000000h
 xor ebx,ebx
 fstp st0
 jmp LZDraw
LClampNeg:
 mov edx,040000000h
 xor ebx,ebx
 fstp st0
 jmp LZDrawNeg
 global D_DrawZSpans
D_DrawZSpans:
 push ebp
 push edi
 push esi
 push ebx
 fld  dword [d_zistepu]
 mov eax, dword [d_zistepu]
 mov esi, dword [4+16+esp]
 test eax,eax
 jz near LFNegSpan
 fmul  dword [Float2ToThe31nd]
 fistp  dword [izistep]
 mov ebx, dword [izistep]
LFSpanLoop:
 fild  dword [4+esi]
 fild  dword [0+esi]
 mov ecx, dword [4+esi]
 mov edi, dword [d_pzbuffer]
 fmul  dword [d_zistepu]
 fxch st1
 fmul  dword [d_zistepv]
 fxch st1
 fadd  dword [d_ziorigin]
 imul ecx, dword [d_zrowbytes]
 faddp st1,st0
 fcom  dword [float_point5]
 add edi,ecx
 mov edx, dword [0+esi]
 add edx,edx
 mov ecx, dword [8+esi]
 add edi,edx
 push esi
 fnstsw ax
 test ah,045h
 jz near LClamp
 fmul  dword [Float2ToThe31nd]
 fistp  dword [izi]
 mov edx, dword [izi]
LZDraw:
 test edi,2
 jz LFMiddle
 mov eax,edx
 add edx,ebx
 shr eax,16
 dec ecx
 mov  word [edi],ax
 add edi,2
LFMiddle:
 push ecx
 shr ecx,1
 jz LFLast
 shr ecx,1
 jnc LFMiddleLoop
 mov eax,edx
 add edx,ebx
 shr eax,16
 mov esi,edx
 add edx,ebx
 and esi,0FFFF0000h
 or eax,esi
 mov  dword [edi],eax
 add edi,4
 and ecx,ecx
 jz LFLast
LFMiddleLoop:
 mov eax,edx
 add edx,ebx
 shr eax,16
 mov esi,edx
 add edx,ebx
 and esi,0FFFF0000h
 or eax,esi
 mov ebp,edx
 mov  dword [edi],eax
 add edx,ebx
 shr ebp,16
 mov esi,edx
 add edx,ebx
 and esi,0FFFF0000h
 or ebp,esi
 mov  dword [4+edi],ebp
 add edi,8
 dec ecx
 jnz LFMiddleLoop
LFLast:
 pop ecx
 pop esi
 and ecx,1
 jz LFSpanDone
 shr edx,16
 mov  word [edi],dx
LFSpanDone:
 mov esi, dword [12+esi]
 test esi,esi
 jnz near LFSpanLoop
 jmp LFDone
LFNegSpan:
 fmul  dword [FloatMinus2ToThe31nd]
 fistp  dword [izistep]
 mov ebx, dword [izistep]
LFNegSpanLoop:
 fild  dword [4+esi]
 fild  dword [0+esi]
 mov ecx, dword [4+esi]
 mov edi, dword [d_pzbuffer]
 fmul  dword [d_zistepu]
 fxch st1
 fmul  dword [d_zistepv]
 fxch st1
 fadd  dword [d_ziorigin]
 imul ecx, dword [d_zrowbytes]
 faddp st1,st0
 fcom  dword [float_point5]
 add edi,ecx
 mov edx, dword [0+esi]
 add edx,edx
 mov ecx, dword [8+esi]
 add edi,edx
 push esi
 fnstsw ax
 test ah,045h
 jz near LClampNeg
 fmul  dword [Float2ToThe31nd]
 fistp  dword [izi]
 mov edx, dword [izi]
LZDrawNeg:
 test edi,2
 jz LFNegMiddle
 mov eax,edx
 sub edx,ebx
 shr eax,16
 dec ecx
 mov  word [edi],ax
 add edi,2
LFNegMiddle:
 push ecx
 shr ecx,1
 jz LFNegLast
 shr ecx,1
 jnc LFNegMiddleLoop
 mov eax,edx
 sub edx,ebx
 shr eax,16
 mov esi,edx
 sub edx,ebx
 and esi,0FFFF0000h
 or eax,esi
 mov  dword [edi],eax
 add edi,4
 and ecx,ecx
 jz LFNegLast
LFNegMiddleLoop:
 mov eax,edx
 sub edx,ebx
 shr eax,16
 mov esi,edx
 sub edx,ebx
 and esi,0FFFF0000h
 or eax,esi
 mov ebp,edx
 mov  dword [edi],eax
 sub edx,ebx
 shr ebp,16
 mov esi,edx
 sub edx,ebx
 and esi,0FFFF0000h
 or ebp,esi
 mov  dword [4+edi],ebp
 add edi,8
 dec ecx
 jnz LFNegMiddleLoop
LFNegLast:
 pop ecx
 pop esi
 and ecx,1
 jz LFNegSpanDone
 shr edx,16
 mov  word [edi],dx
LFNegSpanDone:
 mov esi, dword [12+esi]
 test esi,esi
 jnz near LFNegSpanLoop
LFDone:
 pop ebx
 pop esi
 pop edi
 pop ebp
 ret
















LClamp2:
 mov edx,040000000h
 xor ebx,ebx
 fstp st0
 jmp LZDraw2
LClampNeg2:
 mov edx,040000000h
 xor ebx,ebx
 fstp st0
 jmp LZDrawNeg2
global D_DrawSingleZSpans
D_DrawSingleZSpans:
 push ebp
 push edi
 push esi
 push ebx
 mov  dword [ZScanCount],0
 fld  dword [d_zistepu]
 mov eax, dword [d_zistepu]
 mov esi, dword [4+16+esp]
 test eax,eax
 jz near LFNegSpan2
 fmul  dword [Float2ToThe31nd]
 fistp  dword [izistep]
 mov ebx, dword [izistep]
LFSpanLoop2:
 fild  dword [4+esi]
 fild  dword [0+esi]
 mov ecx, dword [4+esi]
 mov edi, dword [d_pzbuffer]
 fmul  dword [d_zistepu]
 fxch st1
 fmul  dword [d_zistepv]
 fxch st1
 fadd  dword [d_ziorigin]
 imul ecx, dword [d_zrowbytes]
 faddp st1,st0
 fcom  dword [float_point5]
 add edi,ecx
 mov edx, dword [0+esi]
 add edx,edx
 mov ecx, dword [8+esi]
 add edi,edx
 push esi
 fnstsw ax
 test ah,045h
 jz near LClamp2
 fmul  dword [Float2ToThe31nd]
 fistp  dword [izi]
 mov edx, dword [izi]
LZDraw2:
 mov eax,edx
 add edx,ebx
 shr eax,16
 mov  byte [scanList + ecx - 1], 1
 cmp  word [edi],ax
 jle LZSkip
 mov  byte [scanList + ecx - 1], 0
 add  dword [ZScanCount],1
 LZSkip:
 add edi,2
 dec ecx
 jnz LZDraw2

 pop esi
 jmp LFDone2

LFNegSpan2:
 fmul  dword [FloatMinus2ToThe31nd]
 fistp  dword [izistep]
 mov ebx, dword [izistep]
LFNegSpanLoop2:
 fild  dword [4+esi]
 fild  dword [0+esi]
 mov ecx, dword [4+esi]
 mov edi, dword [d_pzbuffer]
 fmul  dword [d_zistepu]
 fxch st1
 fmul  dword [d_zistepv]
 fxch st1
 fadd  dword [d_ziorigin]
 imul ecx, dword [d_zrowbytes]
 faddp st1,st0
 fcom  dword [float_point5]
 add edi,ecx
 mov edx, dword [0+esi]
 add edx,edx
 mov ecx, dword [8+esi]
 add edi,edx
 push esi
 fnstsw ax
 test ah,045h
 jz near LClampNeg2
 fmul  dword [Float2ToThe31nd]
 fistp  dword [izi]
 mov edx, dword [izi]
LZDrawNeg2:
 mov eax,edx
 sub edx,ebx
 shr eax,16
 mov  byte [scanList + ecx - 1], 1
 cmp  word [edi],ax
 jle LZSkip2
 mov  byte [scanList + ecx - 1], 0
 LZSkip2:
 add edi,2
 dec ecx
 jnz near LZDraw2

 pop esi

LFDone2:
 pop ebx
 pop esi
 pop edi
 pop ebp
 ret





 END