; The existing ray/ellipsoid renderer, evaluated in a pin-local orthonormal basis.
DrawBowlingEllipsoid3D PROC uses ebx esi edi centreX:DWORD,centreY:DWORD,centreZ:DWORD,radiusX:DWORD,radiusY:DWORD,radiusZ:DWORD,material:DWORD
    local leftPx:DWORD,rightPx:DWORD,topPx:DWORD,bottomPx:DWORD,column:DWORD,row:DWORD
    local centrePx:DWORD,centreDepth:DWORD,pixelDepth:DWORD,temp:DWORD,texU:DWORD,texV:DWORD
    local texture:DWORD,texWidth:DWORD,texHeight:DWORD,shade:DWORD,color:DWORD
    local worldOX:DWORD,worldOY:DWORD,worldOZ:DWORD,worldRZ:REAL4,boundRadius:DWORD
    local ox:REAL4,oy:REAL4,oz:REAL4,rayX:REAL4,rayY:REAL4,rayZ:REAL4
    local quadraticC:REAL4,quadraticA:REAL4,quadraticB:REAL4,discriminant:REAL4,hitTime:REAL4
    invoke ResolveCitySurface3D,material
    test eax,eax
    jz bp_shape_done
    mov texture,eax
    mov texWidth,ecx
    mov texHeight,edx
    invoke ProjectCityPoint3D,centreX,centreY
    cmp edx,FP_1/8
    jle bp_shape_done
    mov centrePx,eax
    mov centreDepth,edx
    mov eax,radiusX
    cmp eax,radiusZ
    jge @F
    mov eax,radiusZ
@@:
    mov boundRadius,eax
    shl eax,1
    imul eax,SCREEN_H
    cdq
    idiv centreDepth
    mov ecx,centrePx
    sub ecx,eax
    mov leftPx,ecx
    add eax,centrePx
    mov rightPx,eax
    mov eax,viewEye3D
    sub eax,centreZ
    sub eax,boundRadius
    imul eax,SCREEN_H
    cdq
    idiv centreDepth
    add eax,viewHorizon3D
    sub eax,4
    mov topPx,eax
    mov eax,viewEye3D
    sub eax,centreZ
    add eax,boundRadius
    imul eax,SCREEN_H
    cdq
    idiv centreDepth
    add eax,viewHorizon3D
    add eax,4
    mov bottomPx,eax
    cmp leftPx,0
    jge @F
    mov leftPx,0
@@:
    cmp rightPx,SCREEN_W-1
    jle @F
    mov rightPx,SCREEN_W-1
@@:
    cmp topPx,0
    jge @F
    mov topPx,0
@@:
    cmp bottomPx,SCREEN_H-1
    jle @F
    mov bottomPx,SCREEN_H-1
@@:
    mov eax,leftPx
    cmp eax,rightPx
    jge bp_shape_done
    mov eax,topPx
    cmp eax,bottomPx
    jge bp_shape_done
    mov eax,playerX
    sub eax,centreX
    mov worldOX,eax
    mov eax,playerY
    sub eax,centreY
    mov worldOY,eax
    mov eax,viewEye3D
    sub eax,centreZ
    mov worldOZ,eax
    fild worldOX
    fimul bpRenderUX3D
    fild worldOY
    fimul bpRenderUY3D
    faddp st(1),st
    fdiv roofFloatFP3D
    fidiv radiusX
    fstp ox
    fild worldOX
    fimul bpRenderVX3D
    fild worldOY
    fimul bpRenderVY3D
    faddp st(1),st
    fild worldOZ
    fimul bpRenderVZ3D
    faddp st(1),st
    fdiv roofFloatFP3D
    fidiv radiusY
    fstp oy
    fild worldOX
    fimul bpRenderNX3D
    fild worldOY
    fimul bpRenderNY3D
    faddp st(1),st
    fild worldOZ
    fimul bpRenderNZ3D
    faddp st(1),st
    fdiv roofFloatFP3D
    fidiv radiusZ
    fstp oz
    fld ox
    fmul st,st
    fld oy
    fmul st,st
    faddp st(1),st
    fld oz
    fmul st,st
    faddp st(1),st
    fld1
    fsubp st(1),st
    fstp quadraticC
    mov eax,topPx
    mov row,eax
bp_shape_row:
    mov eax,viewHorizon3D
    sub eax,row
    mov temp,eax
    fild temp
    fmul roofFloatFP3D
    fdiv roofFloat4803D
    fstp worldRZ
    mov eax,row
    imul eax,SCREEN_W*4
    mov ebx,leftPx
    lea edi,[eax+ebx*4]
    mov column,ebx
bp_shape_pixel:
    mov ebx,column
    fild cityRayX3D[ebx*4]
    fimul bpRenderUX3D
    fild cityRayY3D[ebx*4]
    fimul bpRenderUY3D
    faddp st(1),st
    fdiv roofFloatFP3D
    fidiv radiusX
    fstp rayX
    fild cityRayX3D[ebx*4]
    fimul bpRenderVX3D
    fild cityRayY3D[ebx*4]
    fimul bpRenderVY3D
    faddp st(1),st
    fld worldRZ
    fimul bpRenderVZ3D
    faddp st(1),st
    fdiv roofFloatFP3D
    fidiv radiusY
    fstp rayY
    fild cityRayX3D[ebx*4]
    fimul bpRenderNX3D
    fild cityRayY3D[ebx*4]
    fimul bpRenderNY3D
    faddp st(1),st
    fld worldRZ
    fimul bpRenderNZ3D
    faddp st(1),st
    fdiv roofFloatFP3D
    fidiv radiusZ
    fstp rayZ
    fld rayX
    fmul st,st
    fld rayY
    fmul st,st
    faddp st(1),st
    fld rayZ
    fmul st,st
    faddp st(1),st
    fstp quadraticA
    fld rayX
    fmul ox
    fld rayY
    fmul oy
    faddp st(1),st
    fld rayZ
    fmul oz
    faddp st(1),st
    fstp quadraticB
    fld quadraticB
    fmul st,st
    fld quadraticA
    fmul quadraticC
    fsubp st(1),st
    fst discriminant
    ftst
    fnstsw ax
    sahf
    fstp st(0)
    jb bp_shape_next
    fld discriminant
    fsqrt
    fadd quadraticB
    fchs
    fdiv quadraticA
    fst hitTime
    fmul roofFloatFP3D
    fistp pixelDepth
    mov eax,pixelDepth
    cmp eax,4096
    jle bp_shape_next
    cmp eax,cityDepthBuffer3D[edi]
    jae bp_shape_next
    fld hitTime
    fmul rayX
    fadd ox
    fld1
    faddp st(1),st
    fmul roofFloatHalfTex3D
    fistp texU
    fld hitTime
    fmul rayZ
    fadd oz
    fchs
    fld1
    faddp st(1),st
    fmul roofFloatHalfTex3D
    fistp texV
    fld hitTime
    fmul rayZ
    fadd oz
    fmul roofFloatShade3D
    fadd roofFloatAmbient3D
    fistp shade
    mov eax,texV
    and eax,255
    mov ecx,texHeight
    imul eax,ecx
    shr eax,8
    imul eax,texWidth
    mov edx,texU
    and edx,255
    imul edx,texWidth
    shr edx,8
    add eax,edx
    mov esi,texture
    mov eax,[esi+eax*4]
    mov color,eax
    movzx eax,al
    imul eax,shade
    shr eax,8
    mov ebx,eax
    mov eax,color
    shr eax,8
    and eax,255
    imul eax,shade
    and eax,0FF00h
    or ebx,eax
    mov eax,color
    shr eax,16
    and eax,255
    imul eax,shade
    and eax,0FF00h
    shl eax,8
    or eax,ebx
    cmp roofCityPass3D,0
    je bp_shape_color_ready
    invoke ShadeRoofCityPixel3D,eax,pixelDepth,256,material
    mov ecx,edi
    shr ecx,2
    mov edx,roofPixelGlow3D
    mov roofGlowMask3D[ecx],dl
bp_shape_color_ready:
    mov screenBuffer[edi],eax
    cmp hallLevel3D,HALL_ROOF
    jne @F
    mov ecx,edi
    shr ecx,2
    mov edx,roofCityPass3D
    mov roofCityMask3D[ecx],dl
@@:
    mov eax,pixelDepth
    mov cityDepthBuffer3D[edi],eax
bp_shape_next:
    add edi,4
    inc column
    mov eax,column
    cmp eax,rightPx
    jbe bp_shape_pixel
    inc row
    mov eax,row
    cmp eax,bottomPx
    jbe bp_shape_row
bp_shape_done:
    ret
DrawBowlingEllipsoid3D ENDP