; Copyright 1996 Acorn Computers Ltd
;
; Licensed under the Apache License, Version 2.0 (the "License");
; you may not use this file except in compliance with the License.
; You may obtain a copy of the License at
;
; http://www.apache.org/licenses/LICENSE-2.0
;
; Unless required by applicable law or agreed to in writing, software
; distributed under the License is distributed on an "AS IS" BASIS,
; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
; See the License for the specific language governing permissions and
; limitations under the License.
;
; > $.Source.VduGrafL
;
; ARTHUR OPERATING SYSTEM - Vdu Drivers
; =======================
;
; Vdu driver code - Sprite stuff
;
; Author T M Dobson
; Date 22-Sep-87
;
; *****************************************************************************
;
; ReadSaveAreaSize - Read size of a VDU context save area
;
; in: R0 = SpriteReason_ReadSaveAreaSize
; R1 -> sprite area
; R2 -> sprite (0 => screen (possibly))
;
; out: R3 = size of an area suitable for this sprite
;
ReadSaveAreaSize ROUT
MOV R3, #MainSize ; I was kidding about it depending
STR R3, [WsPtr, #RetnReg3] ; on the sprite!
MOV PC, R14
; *****************************************************************************
;
; SwitchOutputToSprite - Make VDU(graphics) output go to a sprite
;
; External routine
;
; in: R0 = SpriteReason_SwitchOutputTo <Sprite or Mask>
; R1 -> sprite area
; R2 -> sprite (0 => screen)
; R3 -> save area for VDU variables relating to sprite
; 0 => no save area, initialise variables from mode number of sprite
; or display mode number
; 1 => use MOS's save area
;
; First word of save area = 0 => uninitialised save area
; "VOTS" => initialised save area
; else error
;
; From Medusa onwards, things are further complicated here by the fact that
; the sprite may have a new sprite mode word rather than a mode number. When
; the former case occurs calling pushmodeinfoanymonitor doesn't really help
; very much. Instead, when a sprite mode word is given, it will derive or
; fudge all the variables that it is really interested from the sprite mode
; word directly.
SwitchOutputToSprite ROUT
SwitchOutputToMask ROUT
CMP R3, #1 ; check for values 0 and 1
MOVCC R4, #0 ; R3=0 => no save area, so not inited
ADDEQ R5, WsPtr, #VduSaveArea ; R3=1 => MOS's area
MOVHI R5, R3 ; else user area
LDRCS R4, [R5, #InitFlag] ; if is an area, load R4 with init flag
LDR R5, VOTS ; compare with initialised identifier
TEQ R4, R5 ; if not initialised
TEQNE R4, #0 ; and not uninitialised
BNE InvalidSaveArea
; no more errors can be generated, so update returned registers
ADD R5, WsPtr, #VduOutputCurrentState
LDMIA R5, {R6-R9}
ADD R5, WsPtr, #RetnReg0
STMIA R5, {R6-R9}
Push "R0-R4,R14"
ASSERT SpriteMaskSelect = VduOutputCurrentState +0
ASSERT VduSpriteArea = VduOutputCurrentState + 4
ASSERT VduSprite = VduOutputCurrentState + 8
ORR R0, R0, #RangeC ; make R0 into &2nn
ADD R5, WsPtr, #VduOutputCurrentState
STMIA R5, {R0-R2}
BL PreWrchCursor ; remove cursor
BL PackVars ; save away current vars into save area
; (if any)
Pull "R0-R4"
STR R3, [WsPtr, #VduSaveAreaPtr] ; save new save area ptr
TEQ R2, #0 ; if switching to screen
LDREQ R9, [WsPtr, #DisplayScreenStart] ; then load up new ScreenStart
LDREQ R11, [WsPtr, #DisplayModeNo] ; and mode number
BEQ %FT20 ; and skip sprite stuff
; do stuff for switching to sprite
Push R0
BL RemoveLeftHandWastage ; then remove LH wastage from sprite
Pull R0 ; (spLBit := 0)
ASSERT spHeight = spWidth +4
ASSERT spLBit = spWidth +8
ASSERT spRBit = spWidth +12
ASSERT spImage = spWidth +16
ASSERT spTrans = spWidth +20
ASSERT spMode = spWidth +24
ADD R5, R2, #spWidth ; R5=width:R6=height:R7=LBit(=0)
LDMIA R5, {R5-R11} ; R8=RBit:R9=Image:R10=Trans:R11=Mode
TEQ R0, #SpriteReason_SwitchOutputToMask
BNE %FT23
MOV R9, R10 ; point at mask instead of image
MOVS R0, R11, LSR #27
BEQ %FT23 ; check for old format masks
BL GetMaskspWidth ; adjust R5 and R8 to mask dimensions
BIC R11, R11, #&F8000000
ORR R11, R11, #&08000000 ; force it to a type 1 (1bpp) sprite
23
ADD R9, R9, R2 ; R9 -> sprite data or mask
20
STR R9, [WsPtr, #ScreenStart]
STR R11, [WsPtr, #ModeNo] ; new mode number
MOV R10, R11
BL PushModeInfoAnyMonitor
MOV R11, R13
TEQ R2, #0 ; if outputting to screen
LDREQ R5, [R11, #wkLineLength] ; then load up values
LDREQ R6, [R11, #wkYWindLimit] ; from mode table
LDREQ R7, [R11, #wkXWindLimit]
LDREQ R8, [R11, #wkScrRCol]
LDREQ R10, [R11, #wkScrBRow]
BEQ %FT30 ; and skip more sprite stuff
ADD R5, R5, #1
MOV R5, R5, LSL #2 ; R5 = width in bytes
ADD R7, R8, R5, LSL #3 ; R7 = LineLength*8 + spRBit
SUB R7, R7, #31 ; R7=active area width in bits
LDR R8, [R11, #wkLog2BPC]
MOV R7, R7, LSR R8 ; R7 = width in pixels
MOV R8, R7, LSR #3 ; R8 = width in text columns
SUB R7, R7, #1 ; R7 = max value of GWRCol
SUB R8, R8, #1 ; R8 = max column number
ADD R10, R6, #1 ; R10 = no. of pixel rows
MOV R10, R10, LSR #3 ; R10 = number of char rows
SUB R10, R10, #1 ; R4 = maximum row number
30
STR R5, [WsPtr, #LineLength]
STR R6, [WsPtr, #YWindLimit]
STR R7, [WsPtr, #XWindLimit]
STR R8, [WsPtr, #ScrRCol]
STR R10, [WsPtr, #ScrBRow]
LDR R0,[R11, #wkNColour]
STR R0,[WsPtr, #NColour] ; copy number of colours -1
ADD R11, R11, #wkmiddle
MOV R0, #wkmidend-wkmiddle ; number of bytes to do
ADD R1, WsPtr, #YShftFactor ; first mode variable that we do
40
LDR R5, [R11], #4 ; copy byte from mode table
STR R5, [R1], #4 ; into word variable
SUBS R0, R0, #4 ; decrement count
BNE %BT40 ; loop until finished
ADD R13, R13, #PushedInfoSize ; junked stacked info
; now create other variables from simple ones
LDR R0, [WsPtr, #Log2BPP]
LDR R1, [WsPtr, #Log2BPC]
LDR R5, [WsPtr, #XEigFactor]
LDR R6, [WsPtr, #ModeFlags]
TEQ R2, #0
ORRNE R6, R6, #Flag_HardScrollDisabled ; if sprite then disable hard
STR R6, [WsPtr, #ModeFlags]
;if switching to a sprite, check for full palette 8bpp, and set modeflags and
;NColour to suit.
TEQ R2, #0
BEQ %FT65 ; switching to a sprite ?
CMP R0, #3
BNE %FT65 ; which is 8bpp ?
ADD R7, R2, #spImage ; point R7 at the image/mask start pair
LDMIA R7, {R7, LR} ; fetch them
CMP R7, LR ; which is lower
MOVGT R7, LR ; use the lowest
SUB R7, R7, #spPalette ; get the size of the palette
CMP R7, #&800 ; full 8bpp palette ?
BNE %FT65
ORR R6, R6, #Flag_FullPalette
STR R6, [WsPtr, #ModeFlags] ; set the full palette flag
MOV R7, #255
STR R7, [WsPtr, #NColour] ; and set the number of colours
65
TST R6, #Flag_DoubleVertical
ADREQL R7, WrchNbitTab ; point to correct table
ADRNEL R7, WrchNbitDoubleTab
LDR R8, [R7, R1, LSL #2] ; get offset to correct code
ADD R8, R8, R7 ; convert to absolute address
STR R8, [WsPtr, #WrchNbit]
ADRL R7, CursorNbitTab
LDR R8, [R7, R1, LSL #2]
ADD R8, R8, R7
TST R6, #Flag_Teletext
ADRNEL R8, CursorTeletext
STR R8, [WsPtr, #CursorNbit]
TST R6, #Flag_NonGraphic
MOVEQ R7, #32 ; if graphic mode
MOVEQ R7, R7, LSR R1 ; then = (32 >> lbpc)-1
SUBEQ R7, R7, #1
MOVNE R7, #0 ; else = 0 ;;; NOT REALLY SAFE BET ANYMORE!!!
STR R7, [WsPtr, #NPix]
RSB R7, R1, #5 ; XShftFactor = 5-log2bpc
STR R7, [WsPtr, #XShftFactor]
LDR R7, [WsPtr, #YEigFactor]
SUBS R7, R5, R7 ; XEigFactor-YEigFactor
MOVLT R7, #2 ; X<Y => 2 (vert rect)
MOVGT R7, #1 ; X>Y => 1 (horz rect)
; else X=Y => 0 (square)
STR R7, [WsPtr, #AspectRatio]
MOV R8, #1
MOV R7, R8, LSL R0 ; bpp = 1 << lbpp
STR R7, [WsPtr, #BitsPerPix]
MOV R7, R8, LSL R1 ; bpc = 1 << lbpc
STR R7, [WsPtr, #BytesPerChar]
[ HiResTTX
TST R6, #Flag_Teletext ; in teletext mode
MOVNE R7, R7, LSL #1 ; characters are 16 pixels
STR R7, [WsPtr, #CharWidth]
]
TST R6, #Flag_BBCGapMode ; is it a BBC gap mode ?
MOVNE R7, #&55 ; yes, then use colour 1
BNE %FT70
TEQ R0, #2 ; if (1<<2=4) bits per pixel
MOVEQ R7, #&77 ; then use colour 7 for cursor
MOVNE R7, #&FF ; else use colour 15
[ TTX256
TST R6, #Flag_Teletext ; unless it's teletext
MOVNE R7, #&07 ; in which case still use colour 7
]
70
ORR R7, R7, R7, LSL #8 ; fill out to whole word
ORR R7, R7, R7, LSL #16
STR R7, [WsPtr, #CursorFill]
TST R6, #Flag_DoubleVertical
MOVEQ R7, #8 ; if single vertical then 8 pixels
MOVNE R7, #16 ; if double vertical then 16 pixels
STR R7, [WsPtr, #TCharSizeY]
TST R6, #Flag_GapMode
ADDNE R7, R7, R7, LSR #2 ; make 10 or 20 if gap mode
STR R7, [WsPtr, #RowMult]
STR R7, [WsPtr, #TCharSpaceY]
MOV R8, #8
[ HiResTTX
TST R6, #Flag_Teletext
MOVNE R8, #16
]
STR R8, [WsPtr, #TCharSizeX]
STR R8, [WsPtr, #TCharSpaceX]
LDR R8, [WsPtr, #LineLength]
MUL R7, R8, R7
STR R7, [WsPtr, #RowLength]
; finished doing other variables
SWI XColourTrans_InvalidateCache ; let ColourTrans know we've changed mode
; so that colours get set up correctly
TEQ R4, #0 ; initialising from a save area ?
BEQ %FT80 ; no, then set to defaults
BL UnpackVars
BL AddressCursors
BL ValidateVars
BL PlainBit
BL SetColour
LDR R6, [WsPtr, #CursorFlags]
ORR R6, R6, #TEUpdate ; TextExpand needs updating
STR R6, [WsPtr, #CursorFlags]
B %FT90
80
; *****Change made by DJS
; Original code was:
; MOV R0, #0
; STR R0, [WsPtr, #ECFShift]
; STR R0, [WsPtr, #ECFYOffset]
; This needed to be changed to make the bottom left of the screen (rather
; than the top left) be the default ECF origin.
LDR R0, [WsPtr, #YWindLimit]
ADD R0, R0, #1
AND R0, R0, #7
STR R0, [WsPtr, #ECFYOffset]
MOV R0, #0
STR R0, [WsPtr, #ECFShift]
; *****End of change made by DJS
STR R0, [WsPtr, #ClipBoxEnable]
STRB R0, [R0, #OsbyteVars + :INDEX: VDUqueueItems]
MOV R0, #8
STR R0, [WsPtr, #GCharSizeX] ; chars are 8x8 by default
STR R0, [WsPtr, #GCharSizeY]
STR R0, [WsPtr, #GCharSpaceX] ; and with 8x8 spacing
STR R0, [WsPtr, #GCharSpaceY]
LDR R1, [WsPtr, #ModeFlags]
LDR R0, [WsPtr, #CursorFlags]
BIC R0, R0, #(ActualState :OR: Vdu5Bit)
BIC R0, R0, #(CursorsSplit :OR: PageMode :OR: TeletextMode :OR: ClipBoxEnableBit)
TST R1, #Flag_Teletext ; is it teletext ?
ORRNE R0, R0, #TeletextMode ; yes, then set bit
STR R0, [WsPtr, #CursorFlags]
BLNE TeletextInit ; initialise TTX if appropriate
BL InitCursor ; initialise cursor after
; cursorflags
BL PlainBit ; also sets up RAMMaskTb
BL DefaultColours ; N.B. SetColour is called by both
BL DefaultEcfPattern ; of these.
BL DefaultLineStyle
BL DefaultWindows
BL Home
90
[ STB ; Change made by TMD 29-May-96, to stop cursor flashing before interlace module has
; fixed up LineLength on Service_SwitchingOutputToSprite
MOV R1, #Service_SwitchingOutputToSprite ; issue the service *first*
ADD R2, WsPtr, #VduOutputCurrentState
LDMIA R2, {R2-R5} ; load the registers that were in R0-R3 on entry
IssueService
BL PostWrchCursor ; it should now be safe to restore the cursor
|
BL PostWrchCursor
MOV R1, #Service_SwitchingOutputToSprite ; call Ran's service
ADD R2, WsPtr, #VduOutputCurrentState
LDMIA R2, {R2-R5} ; load the registers that were in R0-R3 on entry
IssueService
]
Pull R14
RETURNVC
InvalidSaveArea
ADRL R0, SpriteErr_InvalidSaveArea
[ International
Push "lr"
BL TranslateError
Pull "lr"
]
STR R0, [WsPtr, #RetnReg0]
RETURNVS
VOTS = "VOTS"
; *****************************************************************************
; Specially saved items
^ 0
InitFlag # 4 ; 0 => uninit, "VOTS" => init
SavedSpoolFileH # 1 ; an OSBYTE variable
SavedWrchDest # 1 ; --------""--------
SavedVDUqueueItems # 1 ; --------""--------
# 1 ; padding to word align it
SavedDataOffset # 0 ; start of compressed data
GBLA FirstOffset
GBLA NextOffset
GBLA CompressedSize
MACRO
CompStart
FirstOffset SETA -1
NextOffset SETA -1
CompressedSize SETA 0
MEND
MACRO
Compress $v0, $v1, $v2, $v3, $v4, $v5, $v6, $v7
[ "$v0"<>""
Compo $v0
]
[ "$v1"<>""
Compo $v1
]
[ "$v2"<>""
Compo $v2
]
[ "$v3"<>""
Compo $v3
]
[ "$v4"<>""
Compo $v4
]
[ "$v5"<>""
Compo $v5
]
[ "$v6"<>""
Compo $v6
]
[ "$v7"<>""
Compo $v7
]
MEND
MACRO
Compo $var
[ FirstOffset <> -1
[ $var = NextOffset
NextOffset SETA ($var)+4
|
DCW FirstOffset
DCW NextOffset
CompressedSize SETA CompressedSize + (NextOffset-FirstOffset)
FirstOffset SETA $var
NextOffset SETA ($var)+4
]
|
FirstOffset SETA $var
NextOffset SETA ($var)+4
]
MEND
MACRO
CompMult $start, $size
[ FirstOffset <> -1
[ $start = NextOffset
NextOffset SETA $start + $size
|
DCW FirstOffset
DCW NextOffset
CompressedSize SETA CompressedSize + (NextOffset-FirstOffset)
FirstOffset SETA $start
NextOffset SETA $start + $size
]
|
FirstOffset SETA $start
NextOffset SETA $start + $size
]
MEND
MACRO
CompRange $start, $end
CompMult $start, ($end+4-$start)
MEND
MACRO
CompEnd
[ FirstOffset <> -1
DCW FirstOffset
DCW NextOffset
CompressedSize SETA CompressedSize + (NextOffset-FirstOffset)
]
& -1
MEND
CompressionTable
CompStart
; CompMult FgEcf, 8*4 ; recreated from GCOLs + ecfs by
; CompMult BgEcf, 8*4 ; call to SetColour
Compress GPLFMD, GPLBMD, GFCOL, GBCOL, GWLCol, GWBRow, GWRCol, GWTRow
CompRange qqqPad, JVec
; Compress ScreenStart ; worked out from sprite address each time
Compress TWLCol, TWBRow, TWRCol, TWTRow
CompRange OrgX, NewPtY
Compress TForeCol, TBackCol, CursorX, CursorY
; Compress CursorAddr, InputCursorAddr - computed from (Input)CursorX,Y
Compress InputCursorX, InputCursorY
Compress VduStatus
Compress CursorDesiredState, CursorStartOffset, CursorEndOffset
Compress CursorCounter, CursorSpeed, Reg10Copy
; Compress CursorFill, CursorNbit - computed from mode variables
; Compress DriverBankAddr - refers to screen always
CompRange Ecf1, Ecf4+4
CompMult DotLineStyle, 8
; Compress ModeNo - stored in sprite itself
Compress TFTint, TBTint, GFTint, GBTint
; Compress TotalScreenSize, MaxMode, ScreenEndAddr - refer to screen always
Compress CursorFlags, CursorStack
Compress ECFShift, ECFYOffset
Compress GCharSizeX, GCharSizeY, GCharSpaceX, GCharSpaceY
; Compress TCharSizeX, TCharSizeY ; recomputed from mode number
; Compress TCharSpaceX, TCharSpaceY ; each time
; CompMult FgEcfOraEor, 64 ; recreated from GCOLs and ecfs
; CompMult BgEcfOraEor, 64 ; by call to SetColour
; CompMult BgEcfStore, 64 ;
Compress LineDotCnt, LineDotPatLSW, LineDotPatMSW, DotLineLength
Compress BBCcompatibleECFs
; Compress WrchNbit - computed from mode number
CompRange ClipBoxEnable, ClipBoxTRow
CompMult FgPattern, 4*8
CompMult BgPattern, 4*8
Compress TextFgColour
Compress TextBgColour
CompEnd
CompressionTableEnd
MainSize * CompressedSize + SavedDataOffset
ASSERT MainSize <= SaveAreaSize
! 0, "Space free in VDU save area = ":CC::STR:(SaveAreaSize-MainSize)
[ {FALSE} ; don't allow teletext mode for now
TTXCompressionTable
CompStart
CompMult TTXDoubleCounts, 28 ; (25 rounded up to a word)
CompMult TTXMap, 41*25*4
CompEnd
TTXCompressionTableEnd
TTXSize * CompressedSize
]
; *****************************************************************************
;
; PackVars - Pack variables into save area
;
PackVars ROUT
CLC ; clear carry - indicate packing
PackOrUnpack
Push "R0-R4,R14"
LDR R0, [WsPtr, #VduSaveAreaPtr]
TEQ R0, #0
Pull "R0-R4,PC", EQ ; ptr=0 => no area
TEQ R0, #1
ADDEQ R0, WsPtr, #VduSaveArea ; ptr=1 => use MOS's save area
BL DoSpecialVars ; process special vars
ADD R0, R0, #SavedDataOffset ; move on to compressed data
ADR R1, CompressionTable
10
LDR R2, [R1], #4
MVNS R3, R2 ; set Z if it was -1 (end of table)
Pull "R0-R4,PC", EQ ; (preserves C)
ADD R3, WsPtr, R2, LSR #16 ; R3 = end pointer
MOV R2, R2, LSL #16
ADD R2, WsPtr, R2, LSR #16 ; R2 = start pointer
20
LDRCC R4, [R2], #4 ; load a word from vars
LDRCS R4, [R0], #4 ; or from save area
STRCC R4, [R0], #4 ; store into save area
STRCS R4, [R2], #4 ; or into vars
TEQ R2, R3 ; end of this block ?
BNE %BT20 ; [no, so loop]
B %BT10 ; go back for another block
; *****************************************************************************
;
; UnpackVars - Unpack variables from save area
;
UnpackVars ROUT
SEC ; set carry - indicate unpacking
B PackOrUnpack
; *****************************************************************************
;
; DoSpecialVars - Pack/unpack special vars: CursorAddr, InputCursorAddr,
; (stored relative to ScreenStart); SpoolFileH, WrchDest, VDUqueueItems
;
; in: R0 -> save area
;
; out: R0 preserved
; R1-R2 corrupted
; Flags preserved
;
DoSpecialVars ROUT
BYTEWS R1
BCS %FT10
LDRB R2, [R1, #:INDEX: SpoolFileH]
STRB R2, [R0, #SavedSpoolFileH]
LDRB R2, [R1, #:INDEX: WrchDest]
STRB R2, [R0, #SavedWrchDest]
LDRB R2, [R1, #:INDEX: VDUqueueItems]
STRB R2, [R0, #SavedVDUqueueItems]
LDR R1, VOTS ; initialised save area identifier
STR R1, [R0, #InitFlag]
MOV PC, R14
; unpack special vars (R1 -> ByteWS)
10
LDRB R2, [R0, #SavedSpoolFileH]
STRB R2, [R1, #:INDEX: SpoolFileH]
LDRB R2, [R0, #SavedWrchDest]
STRB R2, [R1, #:INDEX: WrchDest]
LDRB R2, [R0, #SavedVDUqueueItems]
STRB R2, [R1, #:INDEX: VDUqueueItems]
MOV PC, R14
; *****************************************************************************
;
; ValidateVars - Validate unpacked variables (windows, cursor posns)
;
ValidateVars ROUT
Push R14
ASSERT ScrBRow = ScrRCol + 4
ADD R4, WsPtr, #ScrRCol
LDMIA R4, {R4, R5} ; R4 = ScrRCol; R5 = ScrBRow
ADD R6, WsPtr, #TWLCol ; R0 = TWLCol; R1 = TWBRow
LDMIA R6, {R0-R3} ; R2 = TWRCol; R3 = TWTRow
MOV R7, #0
MOV R8, R5
MOV R9, R4
MOV R10, #0
STMIA R6, {R7-R10} ; set up default window
BL FSRegs ; and attempt to define text window
ASSERT YWindLimit = XWindLimit + 4
ADD R0, WsPtr, #XWindLimit
LDMIA R0, {R2, R3} ; R2 = XWindLimit; R3 = YWindLimit
ADD R8, WsPtr, #GWLCol ; R4 = GWLCol; R5 = GWBRow
LDMIA R8, {R4-R7} ; R6 = GWRCol; R7 = GWTRow
CMP R6, R2 ; if GWRCol > XWindLimit
CMPLS R7, R3 ; or GWTRow > YWindLimit
MOVHI R0, #0
MOVHI R1, #0
STMHIIA R8, {R0-R3} ; then set default graphics window
Pull PC
END