; 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.VduGrafK
;
; ARTHUR OPERATING SYSTEM - Vdu Drivers
; =======================
;
; Vdu driver code - Sprite stuff
;
; Author R C Manby
; Date 5.3.87
;
; *****************************************************************************
;
; ScreenSave - Save screen within graphics window as a sprite file
;
; External routine
;
; in: R2 -> file name
; R3 = 0/1 => exclude/include palette data
;
ScreenSave ROUT
Push R14
SWI XOS_RemoveCursors
[ {TRUE}
GraphicsMode R0
BNE %FT20
|
LDR R0, [WsPtr, #NPix]
CMP R0, #0
BEQ %FT20 ; quit with error if not graphics mode
]
; build a temporary sprite area header
ADD R1, WsPtr, #ScrSavAreaCB
MOV R4, #&7FFFFFFF ; size, very large
MOV R5, #1 ; one sprite
LDR R6, =(ScrSavSpriteCB-ScrSavAreaCB) ;saFirst
MOV R7, R6 ; saFree=saFirst
STMIA R1, {R4-R7}
ADD R11, WsPtr, #GWLCol ; R4 ,R5 ,R6 ,R7
LDMIA R11, {R4,R5,R6,R7} ; wL ,wB ,wR ,wT
LDR R0, [WsPtr, #ModeNo]
STR R0, [WsPtr, #SGetMode] ; needs setting up before CreateHeader
Push R2 ; preserve file name pointer
; if it is a mode selector mode with >256 colours force it to have no
; palette. CreateHeader will deal with <=256.
LDR R2, [WsPtr, #Log2BPP]
CMP R2, #4
MOVCS R3, #0
; amg 25th May 1994. The above is no longer completely true. We still
; don't allow palettes on 16/32bpp. Below that (whether new or old
; format of sprite) palettes are now allowed. No actual code change
; here, but CreateHeader has been changed.
ADR R2, ScrSavSpriteName
; R3 ,R4,R5,R6,R7
BL CreateHeader ; In : Palette,sl,sb,sr,st
ADDVS sp, sp, #4 ; (if error, junk stacked filename ptr and exit)
BVS %FT35
; Out: ImageSize
; now add the sprite to the sprite area
LDR R3, [R2, #spNext] ; total size of new sprite
LDMIA R1, {R4,R5,R6,R7} ; saEnd,saNumber,saFirst,saFree
ADD R7, R7, R3 ; new saFree
MOV R4, R7
STMIA R1, {R4,R5,R6,R7}
; Create file to prevent "Can't extend"
[ AssemblingArthur :LOR: Module
MOV R0, #OSFile_CreateStamp
LDR R1, [R13, #0] ; R1 -> filename
LDR R2, =&FF9 ; Type=SpriteFile
MOV R3, #0 ; Junk
MOV R4, #0
SUB R5, R7, #4 ; File size (ie exclude saEnd)
SWI XOS_File
|
CLRV
]
Pull R1
BVS %FT30
; OpenUp file and save the Sprite area and sprite headers
[ AssemblingArthur :LOR: Module
MOV R0, #open_update :OR: open_mustopen :OR: open_nodir
|
MOV R0, #open_write
]
SWI XOS_Find
BVS %FT30
MOV R1, R0
MOV R0, #2 ; write bytes to file
LDR R2, =(ScrSavAreaCB+saNumber)
ADD R2, R2, WsPtr
LDR R3, =(ScrSavSpriteCB+spImage)
LDR R3, [WsPtr, R3]
ADD R3, R3, #(SpriteAreaCBsize-saNumber)
MOV R4, #0
SWI XOS_GBPB
BVS %FT40 ; FileSwitchGotYa !
Push R1
LDR R0, [WsPtr, #GWLCol]
LDR R1, [WsPtr, #GWTRow]
BL ScreenAddr ; R2 = ScrAdr of TopL of area
Pull R1
LDR R5, [WsPtr, #SGetWidth]
ADD R5, R5, #1
MOV R5, R5, LSL #2 ; width (bytes)
LDR R6, [WsPtr, #SGetHeight] ; height-1
LDR R7, [WsPtr, #LineLength]
SUBS R7, R7, R5 ; zero then can do as one lump
MLAEQ R5, R6, R5, R5 ; R5 = R5*(R6+1)
MOVEQ R6, #0 ; only one chunk to do
;
; R0 ,R1 ,R2 ,R3 ,R4 ,R5 ,R6 ,R7
; ,Handle,ScrAdr,Size , ,Width,RowCnt,RowOfSt
10
MOV R0, #2
MOV R3, R5
SWI XOS_GBPB
BVS %FT40 ; something went wrong
ADD R2, R2, R7 ; step to next screen line
SUBS R6, R6, #1
BGE %BT10
MOV R0, #0 ; close file
SWI XOS_Find
BVS %FT30
SWI XOS_RestoreCursors
Pull R14
RETURNVC ; no error, return VC
20
ADRL R0, SpriteErr_NotGraphics
[ International
BL TranslateError
|
SETV
]
B %FT30
40 ; return point after an error
STR R0, [WsPtr, #RetnReg0] ; R0 ptr to message, R1 file handle
MOV R0, #0 ; close file
SWI XOS_Find
30 ; return point after an error
STRVS R0, [WsPtr, #RetnReg0] ; R0 ptr to message
35
SWI XOS_RestoreCursors
Pull R14
RETURNVS
ScrSavSpriteName
= "screendump", 0
ALIGN
LTORG
; *****************************************************************************
;
; ScreenLoad - Plot sprite file directly into graphics window
;
; External routine
;
; in: R2 -> file name
;
ScreenLoad ROUT
Push R14
SWI XOS_RemoveCursors
MOV R0, #open_read+open_mustopen+open_nodir
MOV R1, R2
SWI XOS_Find
BVS %FT80
STR R0, [WsPtr, #ScrLoaHandle]
MOV R1, R0
MOV R0, #4 ; read areaCB from file
ADD R2, WsPtr, #ScrLoaAreaCB+saNumber
MOV R3, #(SpriteAreaCBsize-saNumber)
MOV R4, #0
SWI XOS_GBPB
BVS %FT70 ; FileSwitchGotYa !
MOV R0, #3 ; read spriteCB from file
ADD R2, WsPtr, #ScrLoaSpriteCB
MOV R3, #SpriteCBsize
ADD R3, R3, #MaxSpritePaletteSize
LDR R4, [WsPtr, #(ScrLoaAreaCB+saFirst)]
SUB R4, R4, #4
SWI XOS_GBPB
BVS %FT70
ADD R2, WsPtr, #ScrLoaSpriteCB
BL WritePaletteFromSprite ; mode change (if needed)
;branch to 75 rather than 70 because RetnRegR0 is already set up
BVS %FT75 ; and palette setting
[ {TRUE}
GraphicsMode R0
BNE %FT60
|
LDR R0, [WsPtr, #NPix]
CMP R0, #0
BEQ %FT60 ; quit with error if not graphics mode
]
; now check for being able to do it all at once
ADD R0, WsPtr, #GWLCol ; R3=GWLCol; R4=GWBRow
LDMIA R0, {R3-R6} ; R5=GWRCol; R6=GWTRow
ADD R0, WsPtr, #ScrLoaSpriteCB
ADD R0, R0, #spWidth ; R7=width-1; R8=height-1
LDMIA R0, {R7-R10} ; R9=LBit; R10=RBit
SUB R5, R5, R3 ; R5 = window width
LDR R0, [WsPtr, #XWindLimit]
TEQ R0, R5 ; if window width=full screen
TEQEQ R9, #0 ; and LBit=0
TEQEQ R10, #31 ; and RBit=31
BNE %FT05
ADD R5, R5, #1 ; R5 = screen width in pixels
ADD R7, R7, #1 ; R7 = sprite width in words
LDR R0, [WsPtr, #NPix]
MLA R0, R7, R0, R7 ; R0 = width*(npix+1)
TEQ R0, R5 ; and spritewidth=full screen
BNE %FT05
[ {TRUE}
LDR R14, [WsPtr, #Log2BPC]
MOV R1, R5, LSL R14 ; bit size of 1 row of pixels
MOV R1, R1, LSR #3 ; byte size of 1 row of pixels
LDR R14, [WsPtr, #LineLength] ; LineLength (in bytes)
TEQ R1, R14 ; if they differ (eg interlaced mode)
BNE %FT05 ; then we can't optimise
]
; we know we can do it all in one chunk
; work out screen address and sprite offset
LDR R1, [WsPtr, #CursorFlags] ; if computing clip box
TST R1, #ClipBoxEnableBit
Push "R0-R4", NE
BLNE SetClipBoxToFullScreen ; then set to full screen
Pull "R0-R4", NE ; above routine preserves PSR
MOV R7, R7, LSL #2 ; R7 = line width in bytes
ADD R1, R8, R4 ; R1 = height-1 + GWBRow = YT
SUBS R9, R1, R6 ; if YT > GWTRow then
; start at row (YT-GWTRow)
MOVHI R1, R6 ; and YT=GWTRow, else
MOVLS R9, #0 ; start at row 0 (and YT=YT)
LDR R0, [WsPtr, #ScrLoaAreaCB+saFirst]
ADD R2, WsPtr, #ScrLoaSpriteCB
LDR R2, [R2, #spImage]
ADD R0, R0, R2
SUB R0, R0, #4 ; R0=offset into file of image
MLA R4, R7, R9, R0 ; add on vertical wastage*width
SUB R9, R8, R9 ; R9 = height-1-wastage
MLA R9, R7, R9, R7 ; number of bytes to transfer
MOV R0, #0
BL ScreenAddr ; R2 := screen address
MOV R3, R9
LDR R1, [WsPtr, #ScrLoaHandle]
MOV R0, #3 ; read from this position
SWI XOS_GBPB
BVS %FT70 ; if error
B %FT52 ; no error
; can't do it all at once; R3 = GWLCol, R4 = GWBRow
05
ADD R2, WsPtr, #ScrLoaSpriteCB ; point at the spriteCB
MOV R5, #0
BL GenSpritePlotParmBlk ; "plotting" at (GWLCol,GWBRow)
BVS %FT55 ; off screen (not an error)
ADD R2, WsPtr, #ScrLoaSpriteCB
LDR R4, [WsPtr, #SPltMemAdr] ; convert MemAdr into
LDR R5, [WsPtr, #ScrLoaAreaCB+saFirst]
SUB R4, R4, #4
SUB R4, R4, R2
ADD R4, R4, R5
STR R4, [WsPtr, #ScrLoaFilPtr] ; file ptr
LDR R4, [R2, #spWidth] ; convert spWidth into
ADD R4, R4, #1
MOV R4, R4, LSL #2
STR R4, [WsPtr, #ScrLoaFilOfst] ; file ptr offset
LDR R4, [WsPtr, #SPltColCnt]
ADD R4, R4, #2
MOV R4, R4, LSL #2
STR R4, [WsPtr, #ScrLoaBytes]
ADD R4, WsPtr, #ScrLoaBuffer
STR R4, [WsPtr, #SPltMemAdr]
STR R4, [WsPtr, #ScrLoaBufAdr]
10 ; read row from file
ADD R1, WsPtr, #ScrLoaHandle
LDMIA R1, {R1,R2,R3,R4} ; Handle,BufAdr,Bytes,FilPtr
MOV R0, #3
SWI XOS_GBPB
BVS %FT70
ADD R0, WsPtr, #SPltScrAdr
LDMIA R0, {R0-R1,R5-R7} ; R0 ,R1 , R5 ,R6 ,R7
; ScrAdr,ColCnt, BufAdr,ShftR,ShftL
LDMIA R5, {R2,R3} ; plot the first (leftmost) word
ADD R5, R5, #4
ShiftR R2,R3, R6,R7 ; shift R3,R2 right R6 places
; we only need result word R2
LDR R3, [WsPtr, #SPltLMask] ; on leftmost word, mask down
AND R2, R2, R3 ; to just the required pixels
LDR R4, [R0] ; plot 1 word
BIC R4, R4, R3
ORR R4, R4, R2
STR R4, [R0], #4
SUBS R1, R1, #1
BLT %FT50 ; if all plotted, try next scanline
; else try for blocks of 4
SUBS R1, R1, #4
BLT %FT30
20
;R0 ,R1 ,R5 ,R6 ,R7
;ScrAdr,ColCnt, ,BufAdr,ShftR,ShftL
LDMIA R5, {R2,R3,R8-R10} ; 5 words needed, gives 4 after shift
ADD R5, R5, #16 ; advance source ptr 4 words
ShiftR R2,R3, R6,R7 ; shift R4-R0 right R6 bits
ShiftR R3,R8, R6,R7 ; we only want result words R3-R0
ShiftR R8,R9, R6,R7
ShiftR R9,R10,R6,R7
STMIA R0!, {R2,R3,R8-R9} ; write 4 words back to screen
SUBS R1, R1, #4
BGE %BT20
30 ; try 1 word at a time
ADDS R1, R1, #4
;R0 ,R1 , R5 ,R6 ,R7
;ScrAdr,ColCnt, BufAdr,ShftR,ShftL
;
; If EQ this is rightmost word
BEQ %FT45
40
LDMIA R5, {R2,R3}
ADD R5, R5, #4
ShiftR R2,R3, R6,R7 ; shift R3,R2 right R6 places
; we only need result word R2
STR R2, [R0], #4
SUBS R1, R1, #1
BGT %BT40
45
LDMIA R5, {R2,R3}
ADD R5, R5, #4
ShiftR R2,R3, R6,R7 ; shift R3,R2 right R6 places
; we only need result word R2
LDR R3, [WsPtr, #SPltRMask] ; rightmost word, so mask down to
AND R2, R2, R3 ; just the required pixels
LDR R4, [R0]
BIC R4, R4, R3
ORR R4, R4, R2
STR R4, [R0], #4
50 ; now try the next scanline
ADD R11, WsPtr, #SPltWidth
LDMIA R11, {R1,R2,R3,R4} ; Width,Height,ScrOff,MemOff
ADD R5, R0, R3
SUBS R2, R2, #1
STMIA R11, {R1,R2,R3,R4,R5} ; Width,Height,ScrOff,MemOff,ScrAdr
ADD R11, WsPtr, #ScrLoaHandle ; R1 ,R2 ,R3 ,R4 ,R5
LDMIA R11, {R1,R2,R3,R4,R5} ; Handle,BufAdr,Bytes,FilPtr,FilOfst
ADD R4, R4, R5
STR R4, [WsPtr, #ScrLoaFilPtr]
BGE %BT10 ; plot next scanline
52
MOV R0, #0 ; close file
SWI XOS_Find
BVS %FT80
55
SWI XOS_RestoreCursors
Pull R14
RETURNVC
60
ADRL R0,SpriteErr_NotGraphics
[ International
BL TranslateError
]
70 ; return point after an error
STR R0, [WsPtr, #RetnReg0] ; R0 ptr to message, R1 file handle
75
MOV R0, #0 ; close file
SWI XOS_Find
80 ; error, file not open
STRVS R0, [WsPtr, #RetnReg0]
SWI XOS_RestoreCursors
Pull R14
RETURNVS
END