;Preferences

PrefDisplayID.l=$0      ; Default (unspecified, as it may possibly retarget if they have gfx card)
;PrefDisplayID.l=$40120000 ; Cybervision Lores 320x240 ?Hz
;PrefDisplayID.l=$21000 ; AGA Lores PAL 320x256 non-laced single-scan 50Hz
;PrefDisplayID.l=$A1000 ; AGA Lores DoublePAL 384x275 non-laced double-scan 48Hz
;PrefDisplayID.l=$89000 ; AGA Lores Super72 384x290 non-laced single-scan 71Hz
;PrefDisplayID.l=$11000 ; AGA Lores NTSC 320x200 non-laced single-scan 60Hz
;PrefDisplayID.l=$39000 ; AGA Lores Multiscan 320x240 double-scan 58Hz
;PrefDisplayID.l=$59000 ; AGA Lores HighGFX 512x250 non-laced single-scan 54Hz
;PrefDisplayID.l=$69000 ; AGA Lores Euro72 320x200 non-laced double-scan 69Hz
;PrefDisplayID.l=$91000 ; AGA Lores DoubleNTSC 384x227 non-laced double-scan 58Hz
;PrefDisplayID.l=$29004 ; AGA PAL 640x400 Hires laced single-scan 50Hz
;PrefDisplayID.l=$19004 ; AGA NTSC 640x400 Hires laced single-scan 60Hz
;PrefDisplayID.l=$39024 ; AGA Multiscan 640x400 Hires non-laced single-scan 58Hz
;PrefDisplayID.l=$69024 ; AGA Euro72 640x400 Hires non-laced single-scan 69Hz
;PrefDisplayID.l=$A9004 ; AGA DoublePAL 640x400 Hires non-laced double-scan 48Hz
;PrefDisplayID.l=$99004 ; AGA DoubleNTSC 640x400 Hires non-laced double-scan 58Hz
PrefDisplayWidth.w=320
PrefDisplayHeight.w=240
PrefDisplayBuffering.b=2 ; 1..3
;If Joyb(0)=0 AND Joyb(1)=0 Then Goto PrefsSkip

#DTAG_DISP=$80000000
#DTAG_DIMS=$80001000
#DTAG_MNTR=$80002000
#DTAG_NAME=$80003000

NEWTYPE.SMode
  DID.l
  DWidth.l
  DHeight.l
  DDepth.w
  DType.w
End NEWTYPE

DEFTYPE.Hook myhook ; The hook for ASL tag as &myhook
myhook\h_Entry=?hook
MOVE.l a5,globalbase
funcret.l=0

Dim SMRtags.TagItem(17)
SMRtags(0)\ti_Tag=#ASLSM_InitialLeftEdge,160
SMRtags(1)\ti_Tag=#ASLSM_InitialTopEdge,0
SMRtags(2)\ti_Tag=#ASLSM_InitialWidth,300
SMRtags(3)\ti_Tag=#ASLSM_InitialHeight,600
SMRtags(4)\ti_Tag=#ASLSM_InitialDisplayID,$21000
SMRtags(5)\ti_Tag=#ASLSM_InitialDisplayDepth,8
SMRtags(6)\ti_Tag=#ASLSM_InitialDisplayWidth,PrefDisplayWidth
SMRtags(7)\ti_Tag=#ASLSM_InitialDisplayHeight,PrefDisplayHeight
SMRtags(8)\ti_Tag=#ASLSM_InitialOverscanType,1
SMRtags(9)\ti_Tag=#ASLSM_InitialInfoOpened,1
SMRtags(10)\ti_Tag=#ASLSM_InitialInfoLeftEdge,350
SMRtags(11)\ti_Tag=#ASLSM_InitialInfoTopEdge,50
SMRtags(12)\ti_Tag=#ASLSM_DoDepth,0
SMRtags(13)\ti_Tag=#ASLSM_DoOverscanType,1
SMRtags(14)\ti_Tag=#ASLSM_DoWidth,1
SMRtags(15)\ti_Tag=#ASLSM_DoHeight,1
SMRtags(16)\ti_Tag=#ASLSM_FilterFunc,&myhook
SMRtags(17)\ti_Tag=#TAG_DONE,0

*sreq.SMode=0
*sreq=AllocAslRequest_(2,&SMRtags(0)\ti_Tag)
ok.b=AslRequest_(*sreq,&SMRtags(0)\ti_Tag)

If ok<>0
  PrefDisplayID.l=*sreq\DID
  PrefDisplayWidth.w=*sreq\DWidth
  PrefDisplayHeight.w=*sreq\DHeight
EndIf
If (*sreq) Then FreeAslRequest_(*sreq)

Goto PrefsSkip

;*************************************************************************
; This is the statement that the hook will call.  Put the label before
; the statement you want to jump to.
Runerrsoff
.hook_jump:
Statement hook{*dahook.Hook, modeID.l, *smr.ScreenModeRequester}
  ; We're inside the hook, and supposedly we should be able to do whatever
  ; we want.
  ; Filter modeID's here
  SHARED funcret.l
  DEFTYPE.DisplayInfo DisInfoBuf
  DEFTYPE.DimensionInfo DimInfoBuf
  DEFTYPE.MonitorInfo MonInfoBuf
  DEFTYPE.NameInfo NamInfoBuf
  ;Refer to Includes/Graphics/DisplayInfo.h or view newtypes
  IDhandle.l=FindDisplayInfo_(modeID)
  GetDisplayInfoData_ IDhandle,&DisInfoBuf,SizeOf.DisplayInfo,#DTAG_DISP,0
  GetDisplayInfoData_ IDhandle,&DimInfoBuf,SizeOf.DimensionInfo,#DTAG_DIMS,0
  GetDisplayInfoData_ IDhandle,&MonInfoBuf,SizeOf.MonitorInfo,#DTAG_MNTR,0
  GetDisplayInfoData_ IDhandle,&NamInfoBuf,SizeOf.NameInfo,#DTAG_NAME,0
  ;Do tests. True=Mode is valid, False=mode is invalid.
  If DimInfoBuf\MaxDepth<>8
    ;No true-colour modes, only 8-bit
    funcret=False
  Else
    funcret=True
  EndIf
End Statement
;*************************************************************************


;*************************************************************************
; Hook
Macro goto_hook
  JSR `1+6
End Macro

globalbase: Dc.l 0

hook: ;This hook is called by the filter hook callback from screenmode requester, per item
; Store registers
MOVEM.l   d1-d7/a0-a6,-(a7) ; Not d0!

; Put parameters into dregs ready for a statement
MOVE.l    a0,d0
MOVE.l    a1,d1
MOVE.l    a2,d2

; Get global variable base
MOVE.l    globalbase,a5

; Goto hook statement
!goto_hook{hook_jump}

GetReg d0,funcret ; return accept/discard

; Restore registers
MOVEM.l   (a7)+,d1-d7/a0-a6 ; Not d0!

RTS

Runerrson
PrefsSkip
PrefDisplayHeight AND $FFFE ; Not odd, otherwise interlaced display wont do all lines