; A single 640x480 bitmap; scan reveal and illumination run entirely in MASM.
ClearKeys3D PROC uses edi
    mov mouseClick3D, 0
    lea edi, keys3D
    xor eax, eax
    mov ecx, 128
    rep stosd
    ret
ClearKeys3D ENDP

FreeStartupAssets3D PROC
    call FreeStartupSequence3D
    cmp startupPixels3D, 0
    je @F
    invoke HeapFree, startupHeap3D, 0, startupPixels3D
    mov startupPixels3D, 0
@@:
    ret
FreeStartupAssets3D ENDP

LoadStartupAssets3D PROC uses ebx
    local count:DWORD
    cmp startupPixels3D, 0
    jne startup_asset_ready
    invoke CreateFileA, OFFSET startupPath3D, 80000000h, 1, 0, 3, 80h, 0
    cmp eax, -1
    je startup_asset_failed
    mov ebx, eax
    invoke ReadFile, ebx, OFFSET startupHeader3D, 16, ADDR count, 0
    test eax, eax
    jz startup_asset_close
    cmp count, 16
    jne startup_asset_close
    cmp startupHeader3D, 31474245h
    jne startup_asset_close
    cmp startupHeader3D[4], SCREEN_W
    jne startup_asset_close
    cmp startupHeader3D[8], SCREEN_H
    jne startup_asset_close
    cmp startupHeader3D[12], INTRO_BYTES
    jne startup_asset_close
    invoke GetProcessHeap
    mov startupHeap3D, eax
    invoke HeapAlloc, eax, 0, INTRO_BYTES
    mov startupPixels3D, eax
    test eax, eax
    jz startup_asset_close
    invoke ReadFile, ebx, startupPixels3D, INTRO_BYTES, ADDR count, 0
    test eax, eax
    jz startup_asset_close
    cmp count, INTRO_BYTES
    jne startup_asset_close
    invoke CloseHandle, ebx
startup_asset_ready:
    mov eax, 1
    ret
startup_asset_close:
    invoke CloseHandle, ebx
    call FreeStartupAssets3D
startup_asset_failed:
    xor eax, eax
    ret
LoadStartupAssets3D ENDP

BeginStartup3D PROC
    mov engineMode, MODE_INTRO
    mov paused3D, 0
    mov interactTargetId, 0
    mov interactPromptPtr, 0
    mov startupElapsed3D, 0
    mov startupVariant3D, 0
    mov animationClock3D, 0
    mov rr3d_state, RR_READY
    call ClearKeys3D
    call LoadStartupAssets3D
    call LoadStartupSequence3D
    ret
BeginStartup3D ENDP

FinishStartup3D PROC
    mov paused3D, 0
    mov interactTargetId, 0
    mov interactPromptPtr, 0
    call ClearKeys3D
    call FreeStartupAssets3D
    call BeginArrival3D
    ret
FinishStartup3D ENDP

HandleStartupInput3D PROC
    mov eax, deltaTime3D
    add startupElapsed3D, eax
    invoke Pressed3D, 71h
    test eax, eax
    jz @F
    xor startupVariant3D, 1
    mov startupElapsed3D, 0
@@:
    invoke Pressed3D, 0Dh
    test eax, eax
    jnz startup_enter
    invoke Pressed3D, 20h
    test eax, eax
    jz startup_input_done
startup_enter:
    call FinishStartup3D
startup_input_done:
    cmp engineMode, MODE_INTRO
    jne @F
    cmp startupElapsed3D, 7000
    jb @F
    call FinishStartup3D
@@:
    ret
HandleStartupInput3D ENDP

RenderStartup3D PROC
    cmp startupVariant3D, 0
    jne startup_studio_variant
    cmp startupSequence3D, 0
    je startup_studio_variant
    call RenderStartupSequence3D
    call FadeStartupOut3D
    ret
startup_studio_variant:
    call RenderStudioStartup3D
    call FadeStartupOut3D
    ret
RenderStartup3D ENDP

FadeStartupOut3D PROC
    cmp startupElapsed3D, 6600
    jb @F
    mov eax, startupElapsed3D
    cmp eax, 7000
    jbe startup_fade_time
    mov eax, 7000
startup_fade_time:
    sub eax, 6600
    shl eax, 8
    xor edx, edx
    mov ecx, 400
    div ecx
    neg eax
    add eax, 256
    invoke FadeCityFrame3D, eax
@@:
    ret
FadeStartupOut3D ENDP

RenderStudioStartup3D PROC uses ebx esi edi
    local row:DWORD, gain:DWORD, reveal:DWORD, beam:DWORD, shiftPx:DWORD, red:DWORD, green:DWORD
    cmp startupPixels3D, 0
    je startup_fallback
    mov eax, startupElapsed3D
    cmp eax, 1200
    jb @F
    mov eax, 1200
@@:
    imul eax, SCREEN_H
    xor edx, edx
    mov ecx, 1200
    div ecx
    mov reveal, eax
    mov eax, startupElapsed3D
    xor edx, edx
    mov ecx, 5400
    div ecx
    mov eax, edx
    imul eax, 600
    xor edx, edx
    div ecx
    sub eax, 60
    mov beam, eax
    mov row, 0
    lea edi, screenBuffer
startup_row:
    mov eax, row
    imul eax, SCREEN_W * 4
    add eax, startupPixels3D
    mov esi, eax
    mov shiftPx, 0
    mov eax, startupElapsed3D
    cmp eax, 1000
    jae startup_steady_gain
    imul eax, 240
    xor edx, edx
    mov ecx, 1000
    div ecx
    add eax, 16
    mov gain, eax
    ; A few moving horizontal slices during the initial signal lock only.
    mov eax, startupElapsed3D
    shr eax, 5
    add eax, row
    and eax, 63
    cmp eax, 4
    jae startup_reveal
    mov shiftPx, 12
    jmp startup_reveal
startup_steady_gain:
    mov gain, 240
startup_reveal:
    mov eax, row
    cmp eax, reveal
    jb startup_beam
    mov gain, 16
startup_beam:
    cmp startupElapsed3D, 1200
    jb startup_pixels
    mov eax, row
    sub eax, beam
    cdq
    xor eax, edx
    sub eax, edx
    cmp eax, 24
    jae startup_pixels
    mov gain, 256
startup_pixels:
    cmp gain, 256
    jne startup_shaded_row
    mov ecx, SCREEN_W
    rep movsd
    jmp startup_next_row
startup_shaded_row:
    xor ebx, ebx
startup_pixel:
    mov ecx, ebx
    add ecx, shiftPx
    cmp ecx, SCREEN_W
    jb @F
    sub ecx, SCREEN_W
@@:
    mov edx, [esi+ecx*4]
    mov eax, edx
    shr eax, 16
    and eax, 255
    imul eax, gain
    shr eax, 8
    shl eax, 16
    mov red, eax
    mov eax, edx
    shr eax, 8
    and eax, 255
    imul eax, gain
    shr eax, 8
    shl eax, 8
    mov green, eax
    mov eax, edx
    and eax, 255
    imul eax, gain
    shr eax, 8
    or eax, green
    or eax, red
    stosd
    inc ebx
    cmp ebx, SCREEN_W
    jb startup_pixel
startup_next_row:
    inc row
    cmp row, SCREEN_H
    jb startup_row
    jmp startup_prompt
startup_fallback:
    lea edi, screenBuffer
    mov eax, 000A1012h
    mov ecx, SCREEN_SIZE
    rep stosd
    invoke DrawString8x8, 140, 84, OFFSET startupName3D, 005FE6F2h
    invoke DrawString8x8, 140, 112, OFFSET startupGames3D, 00E9DBADh
startup_prompt:
    cmp startupElapsed3D, 1200
    jb startup_render_done
    invoke DrawString8x8, 140, 220, OFFSET startupEnter3D, 00F4E4BCh
startup_render_done:
    ret
RenderStudioStartup3D ENDP

include src_graphics\startup_sequence.inc