The Blueprint

Created a blueprint for BLADE.EXE located here

The Update

ResidualVM or ScummVM: I decided to go with ResidualVM since the actors and items will have a greater visual fidelity using a hardware based graphics layer. This past week I begain acquainting myself with the 0.2.1 code line. Being able to play Blade Runner from start to finish in ResidualVM is about a year, or more, away.

Over the next week I will be posting my technical notes.

Finished decoding the initialization method, skipped over AI-ACT1 setup methods, working on decoding the game loop.

MIX Specification see page located on right panel.

I have successfully decoded the first image encountered in Blade Runner [SPLASH.IMG]. I'm working on a specification for Westwood's MIX file format that I will post soon.

DirectDraw and Assembly

Below is the DirectDraw interface being initialized in the method sub_41A7F0. It tells us that dword_47FF3C is an IDirectDraw object.

mov edx, offset dword_47FF3C
push 0
push edx
push 0
call DirectDrawCreate

With that knowledge it is now easier to decode the following:

mov esi, [ebp+arg_0]
mov edx, ds:dword_47FF3C
push 11h
push esi
push edx
mov edx, [edx]
mov eax, [edx+50h]
call eax

Using the IDirectDraw Method Offsets chart below and the ddraw.h file to look up the DDSCL value the above assembly decodes to:

dword_47FF3C->SetCooperativeLevel( arg_0_hWnd, DDSCL_FULLSCREEN );

Now when a method uses dword_47FF3C we know it is part of the video sub-system.

IDirectDraw Method Offsets

Method		Offset
IDirectDraw7_QueryInterface(p, a, b)	(p)->QueryInterface(a, b)	0
IDirectDraw7_AddRef(p)	(p)->AddRef()	4
IDirectDraw7_Release(p)	(p)->Release()	8
IDirectDraw7_Compact(p)	(p)->Compact()	12
IDirectDraw7_CreateClipper(p, a, b, c)	(p)->CreateClipper(a, b, c)	16
IDirectDraw7_CreatePalette(p, a, b, c, d)	(p)->CreatePalette(a, b, c, d)	20
IDirectDraw7_CreateSurface(p, a, b, c)	(p)->CreateSurface(a, b, c)	24
IDirectDraw7_DuplicateSurface(p, a, b)	(p)->DuplicateSurface(a, b)	28
IDirectDraw7_EnumDisplayModes(p, a, b, c, d)	(p)->EnumDisplayModes(a, b, c, d)	32
IDirectDraw7_EnumSurfaces(p, a, b, c, d)	(p)->EnumSurfaces(a, b, c, d)	36
IDirectDraw7_FlipToGDISurface(p)	(p)->FlipToGDISurface()	40
IDirectDraw7_GetCaps(p, a, b)	(p)->GetCaps(a, b)	44
IDirectDraw7_GetDisplayMode(p, a)	(p)->GetDisplayMode(a)	48
IDirectDraw7_GetFourCCCodes(p, a, b)	(p)->GetFourCCCodes(a, b)	52
IDirectDraw7_GetGDISurface(p, a)	(p)->GetGDISurface(a)	56
IDirectDraw7_GetMonitorFrequency(p, a)	(p)->GetMonitorFrequency(a)	60
IDirectDraw7_GetScanLine(p, a)	(p)->GetScanLine(a)	64
IDirectDraw7_GetVerticalBlankStatus(p, a)	(p)->GetVerticalBlankStatus(a)	68
IDirectDraw7_Initialize(p, a)	(p)->Initialize(a)	72
IDirectDraw7_RestoreDisplayMode(p)	(p)->RestoreDisplayMode()	76
IDirectDraw7_SetCooperativeLevel(p, a, b)	(p)->SetCooperativeLevel(a, b)	80
IDirectDraw7_SetDisplayMode(p, a, b, c, d, e)	(p)->SetDisplayMode(a, b, c, d, e)	84
IDirectDraw7_WaitForVerticalBlank(p, a, b)	(p)->WaitForVerticalBlank(a, b)	88
IDirectDraw7_GetAvailableVidMem(p, a, b, c)	(p)->GetAvailableVidMem(a, b, c)	92
IDirectDraw7_GetSurfaceFromDC(p, a, b)	(p)->GetSurfaceFromDC(a, b)	96
IDirectDraw7_RestoreAllSurfaces(p)	(p)->RestoreAllSurfaces()	100
IDirectDraw7_TestCooperativeLevel(p)	(p)->TestCooperativeLevel()	104
IDirectDraw7_GetDeviceIdentifier(p,a,b)	(p)->GetDeviceIdentifier(a,b)	108
IDirectDraw7_StartModeTest(p,a,b,c)	(p)->lpVtbl->StartModeTest(a,b,c)	112
IDirectDraw7_EvaluateMode(p,a,b)	(p)->lpVtbl->EvaluateMode(a,b)	116

IDirectDrawSurface Method Offsets

Method		Offset
IDirectDrawSurface7_QueryInterface(p,a,b)	(p)->lpVtbl->QueryInterface(p,a,b)	0
IDirectDrawSurface7_AddRef(p)	(p)->lpVtbl->AddRef(p)	4
IDirectDrawSurface7_Release(p)	(p)->lpVtbl->Release(p)	8
IDirectDrawSurface7_AddAttachedSurface(p,a)	(p)->lpVtbl->AddAttachedSurface(p,a)	12
IDirectDrawSurface7_AddOverlayDirtyRect(p,a)	(p)->lpVtbl->AddOverlayDirtyRect(p,a)	16
IDirectDrawSurface7_Blt(p,a,b,c,d,e)	(p)->lpVtbl->Blt(p,a,b,c,d,e)	20
IDirectDrawSurface7_BltBatch(p,a,b,c)	(p)->lpVtbl->BltBatch(p,a,b,c)	24
IDirectDrawSurface7_BltFast(p,a,b,c,d,e)	(p)->lpVtbl->BltFast(p,a,b,c,d,e)	28
IDirectDrawSurface7_DeleteAttachedSurface(p,a,b)	(p)->lpVtbl->DeleteAttachedSurface(p,a,b)	32
IDirectDrawSurface7_EnumAttachedSurfaces(p,a,b)	(p)->lpVtbl->EnumAttachedSurfaces(p,a,b)	36
IDirectDrawSurface7_EnumOverlayZOrders(p,a,b,c)	(p)->lpVtbl->EnumOverlayZOrders(p,a,b,c)	40
IDirectDrawSurface7_Flip(p,a,b)	(p)->lpVtbl->Flip(p,a,b)	44
IDirectDrawSurface7_GetAttachedSurface(p,a,b)	(p)->lpVtbl->GetAttachedSurface(p,a,b)	48
IDirectDrawSurface7_GetBltStatus(p,a)	(p)->lpVtbl->GetBltStatus(p,a)	52
IDirectDrawSurface7_GetCaps(p,b)	(p)->lpVtbl->GetCaps(p,b)	56
IDirectDrawSurface7_GetClipper(p,a)	(p)->lpVtbl->GetClipper(p,a)	60
IDirectDrawSurface7_GetColorKey(p,a,b)	(p)->lpVtbl->GetColorKey(p,a,b)	64
IDirectDrawSurface7_GetDC(p,a)	(p)->lpVtbl->GetDC(p,a)	68
IDirectDrawSurface7_GetFlipStatus(p,a)	(p)->lpVtbl->GetFlipStatus(p,a)	72
IDirectDrawSurface7_GetOverlayPosition(p,a,b)	(p)->lpVtbl->GetOverlayPosition(p,a,b)	76
IDirectDrawSurface7_GetPalette(p,a)	(p)->lpVtbl->GetPalette(p,a)	80
IDirectDrawSurface7_GetPixelFormat(p,a)	(p)->lpVtbl->GetPixelFormat(p,a)	84
IDirectDrawSurface7_GetSurfaceDesc(p,a)	(p)->lpVtbl->GetSurfaceDesc(p,a)	88
IDirectDrawSurface7_Initialize(p,a,b)	(p)->lpVtbl->Initialize(p,a,b)	92
IDirectDrawSurface7_IsLost(p)	(p)->lpVtbl->IsLost(p)	96
IDirectDrawSurface7_Lock(p,a,b,c,d)	(p)->lpVtbl->Lock(p,a,b,c,d)	100
IDirectDrawSurface7_ReleaseDC(p,a)	(p)->lpVtbl->ReleaseDC(p,a)	104
IDirectDrawSurface7_Restore(p)	(p)->lpVtbl->Restore(p)	108
IDirectDrawSurface7_SetClipper(p,a)	(p)->lpVtbl->SetClipper(p,a)	112
IDirectDrawSurface7_SetColorKey(p,a,b)	(p)->lpVtbl->SetColorKey(p,a,b)	116
IDirectDrawSurface7_SetOverlayPosition(p,a,b)	(p)->lpVtbl->SetOverlayPosition(p,a,b)	120
IDirectDrawSurface7_SetPalette(p,a)	(p)->lpVtbl->SetPalette(p,a)	124
IDirectDrawSurface7_Unlock(p,b)	(p)->lpVtbl->Unlock(p,b)	128
IDirectDrawSurface7_UpdateOverlay(p,a,b,c,d,e)	(p)->lpVtbl->UpdateOverlay(p,a,b,c,d,e)	132
IDirectDrawSurface7_UpdateOverlayDisplay(p,a)	(p)->lpVtbl->UpdateOverlayDisplay(p,a)	136
IDirectDrawSurface7_UpdateOverlayZOrder(p,a,b)	(p)->lpVtbl->UpdateOverlayZOrder(p,a,b)	140
IDirectDrawSurface7_GetDDInterface(p,a)	(p)->lpVtbl->GetDDInterface(p,a)	144
IDirectDrawSurface7_PageLock(p,a)	(p)->lpVtbl->PageLock(p,a)	148
IDirectDrawSurface7_PageUnlock(p,a)	(p)->lpVtbl->PageUnlock(p,a)	152
IDirectDrawSurface7_SetSurfaceDesc(p,a,b)	(p)->lpVtbl->SetSurfaceDesc(p,a,b)	156
IDirectDrawSurface7_SetPrivateData(p,a,b,c,d)	(p)->lpVtbl->SetPrivateData(p,a,b,c,d)	160
IDirectDrawSurface7_GetPrivateData(p,a,b,c)	(p)->lpVtbl->GetPrivateData(p,a,b,c)	164
IDirectDrawSurface7_FreePrivateData(p,a)	(p)->lpVtbl->FreePrivateData(p,a)	168
IDirectDrawSurface7_GetUniquenessValue(p, a)	(p)->lpVtbl->GetUniquenessValue(p, a)	172
IDirectDrawSurface7_ChangeUniquenessValue(p)	(p)->lpVtbl->ChangeUniquenessValue(p)	176
IDirectDrawSurface7_SetPriority(p,a)	(p)->lpVtbl->SetPriority(p,a)	180
IDirectDrawSurface7_GetPriority(p,a)	(p)->lpVtbl->GetPriority(p,a)	184
IDirectDrawSurface7_SetLOD(p,a)	(p)->lpVtbl->SetLOD(p,a)	188
IDirectDrawSurface7_GetLOD(p,a)	(p)->lpVtbl->GetLOD(p,a)	192

Blade Runner shipped with DirectX 5, so be careful.

I'm decoding the file sub-system now. When I'm done I will post my notes on how it works. Most of the reverse engineering has taken place in notepad++ by reading the ASM file in one tab and writing pseudo code in another tab. I use hex editor plugin for notepad++ to view the resource files.

Architecture

From an architecture perspective BLADE.EXE is a black box that receives input (mouse/keyboard) and generates output (screen and files). As this project progresses the diagram below will show the internal architecture of BLADE.EXE.