; Doorways show the adjacent native scene through a depth-tested screen-space
; aperture. Camera translations are the same as the walking thresholds.
DrawInteriorView3D PROC uses ebx esi edi axis:DWORD,plane:DWORD,lo:DWORD,hi:DWORD,z0:DWORD,z1:DWORD,offsetX:DWORD,offsetY:DWORD,offsetZ:DWORD,targetMap:DWORD,targetMode:DWORD,targetLevel:DWORD,targetFloor:DWORD,targetRoute:DWORD
    local oldX:DWORD,oldY:DWORD,oldEye:DWORD,oldCeiling:DWORD,oldMap:DWORD
    local oldMode:DWORD,oldLevel:DWORD,oldFloor:DWORD,oldRoute:DWORD
    local found:DWORD,depth:DWORD,row:DWORD,pixel:DWORD
    mov found,0
    xor ebx,ebx
portal_mask_column:
    mov portalClipDepth3D[ebx*4],0
    cmp axis,0
    jne portal_mask_y
    invoke CityRayPlane3D,plane,playerX,cityRayX3D[ebx*4]
    jmp portal_mask_depth
portal_mask_y:
    invoke CityRayPlane3D,plane,playerY,cityRayY3D[ebx*4]
portal_mask_depth:
    cmp eax,2048
    jle portal_mask_next
    ; The aperture is visible throughout the room, not just within eight metres.
    cmp eax,64*FP_1
    ja portal_mask_next
    cmp eax,zBuffer[ebx*4]
    ja portal_mask_next
    mov depth,eax
    cmp axis,0
    jne portal_along_x
    imul cityRayY3D[ebx*4]
    shrd eax,edx,16
    add eax,playerY
    jmp portal_mask_along
portal_along_x:
    imul cityRayX3D[ebx*4]
    shrd eax,edx,16
    add eax,playerX
portal_mask_along:
    cmp eax,lo
    jl portal_mask_next
    cmp eax,hi
    jge portal_mask_next
    mov eax,viewEye3D
    sub eax,z1
    imul eax,SCREEN_H
    cdq
    idiv depth
    add eax,viewHorizon3D
    test eax,eax
    jns @F
    xor eax,eax
@@:
    mov portalClipTop3D[ebx*4],eax
    mov eax,viewEye3D
    sub eax,z0
    imul eax,SCREEN_H
    cdq
    idiv depth
    add eax,viewHorizon3D
    cmp eax,SCREEN_H
    jle @F
    mov eax,SCREEN_H
@@:
    cmp eax,portalClipTop3D[ebx*4]
    jle portal_mask_next
    mov portalClipBottom3D[ebx*4],eax
    mov eax,depth
    mov portalClipDepth3D[ebx*4],eax
    inc found
portal_mask_next:
    inc ebx
    cmp ebx,SCREEN_W
    jb portal_mask_column
    cmp found,0
    je portal_view_done
    cld
    lea esi,screenBuffer
    lea edi,portalSourcePixels3D
    mov ecx,SCREEN_SIZE
    rep movsd
    lea esi,cityDepthBuffer3D
    lea edi,portalSourceDepth3D
    mov ecx,SCREEN_SIZE
    rep movsd
    lea esi,zBuffer
    lea edi,portalSourceWalls3D
    mov ecx,SCREEN_W
    rep movsd
    mov eax,playerX
    mov oldX,eax
    add eax,offsetX
    mov playerX,eax
    mov eax,playerY
    mov oldY,eax
    add eax,offsetY
    mov playerY,eax
    mov eax,viewEye3D
    mov oldEye,eax
    add eax,offsetZ
    mov viewEye3D,eax
    mov eax,viewCeiling3D
    mov oldCeiling,eax
    mov viewCeiling3D,FP_1*5/2
    cmp targetMode,MODE_STAIRS
    jne @F
    mov viewCeiling3D,FP_1*11/2
    cmp targetRoute,3
    jne @F
    mov viewCeiling3D,4*FP_1
@@:
    mov eax,worldMap3D
    mov oldMap,eax
    mov eax,targetMap
    mov worldMap3D,eax
    mov eax,engineMode
    mov oldMode,eax
    mov eax,targetMode
    mov engineMode,eax
    mov eax,hallLevel3D
    mov oldLevel,eax
    mov eax,targetLevel
    mov hallLevel3D,eax
    cmp eax,HALL_BOWLING
    jne @F
    mov viewCeiling3D,6*FP_1
@@:
    mov eax,floorTexture3D
    mov oldFloor,eax
    mov eax,targetFloor
    mov floorTexture3D,eax
    mov eax,stairRoute3D
    mov oldRoute,eax
    mov eax,targetRoute
    mov stairRoute3D,eax
    mov portalRendering3D,1
    call UpdateCamera3D
    cmp targetLevel,HALL_BOWLING
    je portal_target_world_ready
    call RenderCeilingAndFloor
    call RenderWalls
    call PrepareCityDepth3D
    call RenderSprites
portal_target_world_ready:
    call RenderHall3D
    mov portalRendering3D,0
    mov eax,oldX
    mov playerX,eax
    mov eax,oldY
    mov playerY,eax
    mov eax,oldEye
    mov viewEye3D,eax
    mov eax,oldCeiling
    mov viewCeiling3D,eax
    mov eax,oldMap
    mov worldMap3D,eax
    mov eax,oldMode
    mov engineMode,eax
    mov eax,oldLevel
    mov hallLevel3D,eax
    mov eax,oldFloor
    mov floorTexture3D,eax
    mov eax,oldRoute
    mov stairRoute3D,eax
    mov row,0
    xor edi,edi
portal_compose_row:
    xor ebx,ebx
portal_compose_pixel:
    mov eax,portalClipDepth3D[ebx*4]
    test eax,eax
    jz portal_restore_pixel
    mov ecx,row
    cmp ecx,portalClipTop3D[ebx*4]
    jl portal_restore_pixel
    cmp ecx,portalClipBottom3D[ebx*4]
    jge portal_restore_pixel
    cmp eax,portalSourceDepth3D[edi]
    ja portal_restore_pixel
    ; The rendered destination is already in screenBuffer at this exact ray.
    ; Keep destination depth, so the hinged leaf can occlude the continuation.
    inc portalPixelsWritten3D
    jmp portal_compose_next
portal_restore_pixel:
    mov eax,portalSourcePixels3D[edi]
    mov screenBuffer[edi],eax
    mov eax,portalSourceDepth3D[edi]
    mov cityDepthBuffer3D[edi],eax
portal_compose_next:
    add edi,4
    inc ebx
    cmp ebx,SCREEN_W
    jb portal_compose_pixel
    inc row
    cmp row,SCREEN_H
    jb portal_compose_row
    lea esi,portalSourceWalls3D
    lea edi,zBuffer
    mov ecx,SCREEN_W
    rep movsd
    call UpdateCamera3D
    call PrepareCityRays3D
portal_view_done:
    ret
DrawInteriorView3D ENDP

RenderInteriorViews3D PROC
    cmp portalRendering3D,0
    jne interior_views_done
    mov portalPixelsWritten3D,0
    cmp hallLevel3D,0
    jne @F
    call RenderBowlingEntrance3D
@@:
    cmp hallLevel3D,3
    je RenderFortuneViews3D
    cmp engineMode,MODE_STAIRS
    jne @F
    cmp stairRoute3D,3
    je RenderFortuneViews3D
@@:
    cmp engineMode,MODE_STAIRS
    je interior_views_stairs
    cmp hallLevel3D,2
    je interior_views_lounge
    cmp hallLevel3D,1
    je interior_views_bunker
    call RenderFortuneViews3D
    cmp playerX,FP_1*303/10
    jae @F
    invoke DrawInteriorView3D,0,FP_1*3025/100,20*FP_1,22*FP_1,0,FP_1*5/2,-27*FP_1,0,0,OFFSET upperStairMap3D,MODE_STAIRS,0,85,2
@@:
    cmp basementDoorOpen3D,0
    je interior_views_done
    cmp playerX,29*FP_1
    jae interior_views_done
    invoke DrawInteriorView3D,0,FP_1*2895/100,FP_1*975/100,FP_1*1125/100,0,FP_1*19/10,-25*FP_1,FP_1*21/2,FP_1*3/2,OFFSET basementStairMap3D,MODE_STAIRS,0,94,1
    ret
interior_views_lounge:
    cmp playerX,FP_1*32/10
    jbe interior_views_done
    invoke DrawInteriorView3D,0,FP_1*325/100,20*FP_1,22*FP_1,0,FP_1*5/2,12*FP_1,0,FP_1*13/5,OFFSET upperStairMap3D,MODE_STAIRS,2,85,2
    ret
interior_views_bunker:
    cmp playerY,FP_1*277/10
    jae interior_views_done
    invoke DrawInteriorView3D,1,FP_1*2765/100,15*FP_1,18*FP_1,0,FP_1*5/2,0,-13*FP_1,0,OFFSET basementStairMap3D,MODE_STAIRS,1,94,1
    ret
interior_views_stairs:
    cmp stairRoute3D,1
    je interior_views_concrete
    cmp playerX,FP_1*31/10
    jbe @F
    invoke DrawInteriorView3D,0,FP_1*315/100,20*FP_1,22*FP_1,0,FP_1*5/2,27*FP_1,0,0,OFFSET casinoMap,MODE_WALK,0,100,0
@@:
    cmp playerX,16*FP_1
    jae interior_views_done
    invoke DrawInteriorView3D,0,FP_1*159/10,20*FP_1,22*FP_1,FP_1*13/5,FP_1*51/10,-12*FP_1,0,-FP_1*13/5,OFFSET upperLoungeMap3D,MODE_WALK,2,124,0
    ret
interior_views_concrete:
    cmp playerX,FP_1*31/10
    jbe @F
    invoke DrawInteriorView3D,0,FP_1*315/100,FP_1*2025/100,FP_1*2175/100,FP_1*3/2,FP_1*34/10,25*FP_1,-FP_1*21/2,-FP_1*3/2,OFFSET casinoMap,MODE_WALK,0,100,0
@@:
    cmp playerY,FP_1*143/10
    jbe interior_views_done
    invoke DrawInteriorView3D,1,FP_1*144/10,15*FP_1,18*FP_1,0,FP_1*5/2,0,13*FP_1,0,OFFSET bunkerMap3D,MODE_WALK,1,94,0
interior_views_done:
    ret
RenderInteriorViews3D ENDP