; 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.VduGrafJ
;
; ARTHUR OPERATING SYSTEM - Vdu Drivers
; =======================
;
; Vdu driver code - Sprite stuff
;
; Author R C Manby
; Date 10.11.86
;
; *****************************************************************************
;
; GetSpriteUserCoords - Pick up area of screen as sprite using
; given external coordinates
;
; External routine
;
; in: R1 -> sprite area
; R2 -> sprite name
; R3 = 0 => exclude palette data
; 1 => include palette data
; R4,R5 = (X,Y) EXTERNAL coordinates of one corner of box
; R6,R7 = (X,Y) EXTERNAL coordinates of opposite corner of box
;
GetSpriteUserCoords ROUT
Push "R1-R3, R14"
ADD R8, WsPtr, #GCsX
LDMIA R8, {R9,R10} ; preserve GCsX,GCsY around EIG
MOV R0, R4
MOV R1, R5
MOV R2, #4 ; indicate absolute coord
BL EIG
MOV R4, R0
MOV R5, R1
MOV R0, R6
MOV R1, R7
BL EIG
MOV R6, R0
MOV R7, R1
STMIA R8, {R9,R10} ; restore GcsX,GCsY
Pull "R1-R3, R14"
B GetSpr05
; *****************************************************************************
;
; GetSprite - Pick up area of screen bounded by OldCs and GCsI as sprite
;
; External routine + GetSpr05 called by GetSpriteUserCoords
; (also external)
;
; in: R1 -> sprite area
; R2 -> sprite name
; R3 = 0 => exclude palette data
; 1 => include palette data
; OldCsX,OldCsY = (X,Y) INTERNAL coordinates of one corner of box
; GCsIX, GCsIY = (X,Y) INTERNAL coordinates of opposite corner of box
;
GetSprite ROUT
ADD R4, WsPtr, #OldCsX ; pickup area given by OldCs
LDMIA R4, {R4-R7} ; and GCsIX
GetSpr05
Push R14
[ {TRUE}
GraphicsMode R0
BNE %FT70
|
LDR R0, [WsPtr, #NPix]
TEQ R0, #0
BEQ %FT70 ; quit with error if not graphics mode
]
KillSpChoosePtr
SortT R4, R6, R8 ; R4 ,R5, R6 ,R7 N.B. BotL &
SortT R5, R7, R8 ; sL ,sB, sR ,sT TopR
LDR R8, [WsPtr, #YWindLimit]
SUB R8, R8, R7 ; use inverted sT as index
AND R8, R8, #7 ; into EcfPatternTable
STR R8, [WsPtr, #SGetEcfIndx]
LDR R0, [WsPtr, #ModeNo]
STR R0, [WsPtr, #SGetMode] ; needs setting up before CreateHeader
Push R2
BL SpriteCtrlBlk
BVC %FT90 ; sprite already exists, so be clever
Pull R2 ; restore name pointer
; R1 ,R2 ,R3 ,R4,R5,R6,R7
BL CreateHeader ; In : AreaPtr,NamePtr,Palette ,sl,sb,sr,st
; Out: ImageSize,lx,ty,
BVS %FT80 ; Error, (no room/not a graphics mode)
BL GetSpriteData
; R1 -> sprite area, R2 -> sprite
; now add the sprite to the sprite area
LDR R3, [R2, #spNext] ; total size of new sprite
LDMIA R1, {R4-R7} ; saEnd,saNumber,saFirst,saFree
ADD R5, R5, #1
ADD R7, R7, R3
STMIA R1, {R4-R7}
; have we made a new format sprite ? if so no left hand wastage is allowed.
LDR R3, [R2, #spMode]
CMP R3, #256
BLCS RemoveLeftHandWastage
BL SelectSprite
SWI XOS_RestoreCursors
Pull R14
RETURNVC
70
ADRL R0, SpriteErr_NotGraphics
[ International
BL TranslateError
]
75
STR R0, [WsPtr, #RetnReg0]
80 ; return point after an error
Pull R14
RETURNVS
; come here if sprite already exists
; we want to extend or reduce existing sprite as necessary
90
ADD R13, R13, #4 ; throw away stacked name ptr
LDR R14, [WsPtr, #VduSprite]
TEQ R14, R2 ; if same as vdu output sprite
ADREQL R0, SpriteErr_SpriteIsCurrentDest
[ International
BLEQ TranslateError
]
BEQ %BT75 ; then error
[ No26bitCode
ADR R14, %FT95
|
ADR R14, %FT95+SVC_mode ; Enable interrupts on return from PostCreateHeader
]
Push "R1, R14"
ADD R8, WsPtr, #NameBuf
LDMIA R8, {R9-R11} ; load 3 words of name
ADD R8, WsPtr, #SGetName
STMIA R8, {R9-R11} ; and store in SGetName
Push "R1, R2, R3" ; save sprite area, sprite, palflag
BL PreCreateHeader
Pull "R1, R2" ; restore sprite area ptr + sprite ptr
BVS %FT93
; R4 = total size of sprite
Push R4 ; save new size of sprite
LDR R0, [R2, #spNext]
SUBS R3, R4, R0 ; compare required size with existing
MOV R3, R3, ASR #2 ; no. of words to extend/reduce by
BEQ %FT94 ; [is exactly right already]
BHI %FT92 ; need to extend sprite
; need to reduce sprite
RSB R3, R3, #0 ; no. of words to reduce by
LDR R4, [R2, #spImage]
SUB R4, R0, R4 ; offset from Image to Next
SUB R4, R4, R3, LSL #2 ; dest. start as offset from spImage
BL RemoveWords
RSB R3, R3, #0 ; put R3 back to no. of words to extend
B %FT94
; need to extend sprite
92
BL ExtendSpriteByR3
93
ADDVS R13, R13, #4*4 ; junk size, palflag,
; sprite area, fake return address
BVS %BT80 ; no room to extend sprite
94
Pull R4 ; restore new size of sprite
B PostCreateHeader
; come back to here after PostCreateHeader exits
; R1 -> sprite area, R2 -> sprite, R3 = no. of words to extend by
95
[ No26bitCode
; Enable interrupts here for 32bit machines
WritePSRc SVC_mode, R14
]
BL GetSpriteData
BL SelectSprite
; have we made a new format sprite ? if so no left hand wastage is allowed.
LDR R3, [R2, #spMode]
CMP R3, #256
BLCS RemoveLeftHandWastage
SWI XOS_RestoreCursors
Pull R14
RETURNVC
; *****************************************************************************
GetSpriteData ROUT
Push "R1-R3, R14"
SWI XOS_RemoveCursors
MOV R0, R4
MOV R1, R5
BL ScreenAddr
MOV R0, R2 ; screen addr of TopL of area
LDMIA R13, {R4,R5} ; R4->sprite area, R5->sprite
LDR R1, [WsPtr, #SGetImage]
ADD R1, R1, R5 ; memory address
LDR R2, [WsPtr, #SGetWidth]
ADD R2, R2, #1 ; sprite width (words)
LDR R3, [WsPtr, #SGetHeight] ; height
ADD R3, R3, #1
LDR R8, [WsPtr, #SGetTopMargin] ; gap above window (rows)
LDR R9, [WsPtr, #SGetBotMargin] ; below (rows)
LDR R10, [WsPtr, #SGetLWrdMargin] ; left of (words)
LDR R11, [WsPtr, #SGetRWrdMargin] ; right of (words)
SUB R2, R2, R10
SUBS R2, R2, R11 ; number words in window per scanline
BLEQ PaintSprite ; Left or Right of window
BEQ %FT60
SUB R3, R3, R8
SUBS R3, R3, R9 ; number of rows in window
BLEQ PaintSprite ; above or below window
BEQ %FT60
LDR R14, [WsPtr, #LineLength] ; offset from RHend of row to LHend
SUB R14, R14, R2, LSL #2 ; of next row
STR R14, [WsPtr, #SGetRowOfst]
LDR R11, [WsPtr, #SGetLBitMargin]
MOV R5, #&FFFFFFFF
MOV R5, R5, LSL R11 ; LmarginMask
LDR R11, [WsPtr, #SGetRBitMargin]
MOV R6, #&FFFFFFFE
MVN R6, R6, LSL R11 ; RmarginMask
SUBS R2, R2, #1
STR R2, [WsPtr, #SGetColWCnt] ; if only one word in window per row
ANDEQ R5, R5, R6 ; then combine L&R masks
MOVEQ R6, R5
STR R5, [WsPtr, #SGetLBitMargin]
STR R6, [WsPtr, #SGetRBitMargin]
LDR R5, [WsPtr, #SGetTopMargin] ; paint TopMargin (if any)
CMP R5, #0
BLNE PaintBlock
; R0 ,R1 ,R2 ,R3 ,R4 .. R11
; ScrAdr,MemAdr,ColWCnt,RowCnt,{8 words from screen},
10
LDR R4, [WsPtr, #SGetLWrdMargin] ; paint 1 row of LHmargin (if any)
CMP R4, #0
BLNE PaintRow ; on exit R6 holds word of BgEcf, if not called
; R6 is corrupt, but it doesn't matter
LDR R2, [WsPtr, #SGetColWCnt] ; on screen word count ( >0 in words)
LDR R5, [WsPtr, #SGetLBitMargin]
LDR R4, [R0], #4 ; get first on screen word
AND R4, R4, R5
BIC R6, R6, R5 ; Write BgEcf (or nonsense) to out of window
ORR R4, R4, R6 ; pixels
STR R4, [R1], #4
SUBS R2, R2, #1
BLT %FT50 ; if all plotted
SUBS R2, R2, #8 ; try for 8 words
20
LDMCSIA R0!, {R4-R11} ; copy 8 words from screen to memory
STMCSIA R1!, {R4-R11}
SUBCSS R2, R2, #8
BCS %BT20
30
ADDS R2, R2, #8
LDR R6, [WsPtr,#SGetEcfIndx]
ADD R6, WsPtr, R6, LSL #2
LDR R6, [R6, #BgEcf] ; BgEcf for this scanline
LDR R5, [WsPtr,#SGetRBitMargin]
BIC R6, R6, R5
40
LDR R4, [R0], #4
ANDEQ R4, R4, R5
ORREQ R4, R4, R6
STR R4, [R1], #4
SUBS R2, R2, #1
BCS %BT40
50
LDR R4, [WsPtr, #SGetRWrdMargin]
CMP R4, #0
BLNE PaintRow
LDR R2, [WsPtr, #SGetColWCnt]
LDR R4, [WsPtr, #SGetRowOfst]
LDR R5, [WsPtr,#SGetEcfIndx]
ADD R0, R0, R4 ; offset ScrAdr to next row
ADD R5, R5, #1
AND R5, R5, #7
STR R5, [WsPtr, #SGetEcfIndx] ; update EcfIndx to next row
SUBS R3, R3, #1
BGT %BT10 ; do next screen line
LDR R5, [WsPtr, #SGetBotMargin] ; paint bottom margin (if any)
CMP R5, #0
BLNE PaintBlock
60
Pull "R1-R3, PC"
; *****************************************************************************
;
; PaintSprite - Paint the whole of the sprite in background colour
;
; Internal routine, called by GetSprite when all area is outside window
;
; in: R1 -> first byte in sprite
;
PaintSprite ROUT
LDR R5, [WsPtr, #SGetHeight]
ADD R5, R5, #1 ; R5 = number of rows in sprite
; and drop thru to ...
; *****************************************************************************
;
; PaintBlock - Paint a number of rows of the sprite in background colour
;
; Internal routine, called by GetSprite to do area above and below window
; and dropped thru to by PaintSprite
;
; in: R1 -> start of first row to paint
; R5 = number of rows to do
;
; out: Flags preserved
PaintBlock ROUT
[ No26bitCode
MRS R4, CPSR
Push "R4,R14"
|
Push R14
]
LDR R4, [WsPtr, #SGetWidth]
ADD R4, R4, #1
10
BL PaintRow
LDR R6, [WsPtr, #SGetEcfIndx]
ADD R6, R6, #1
AND R6, R6, #7
STR R6, [WsPtr, #SGetEcfIndx]
SUBS R5, R5, #1
BNE %BT10
[ No26bitCode
Pull "R4,R14"
MSR CPSR_f, R4
MOV PC,R14
|
Pull PC,,^ ; we must preserve the flags
]
; *****************************************************************************
;
; PaintRow - Paint part of a row in sprite with background colour
;
; Internal routine, called by GetSprite to do areas left+right of window
; and by PaintBlock
;
; in: R1 -> first word to paint
; R4 = number of words to paint
;
; out: R4 preserved
;
PaintRow ROUT
Push R4
LDR R6, [WsPtr, #SGetEcfIndx]
ADD R6, WsPtr, R6, LSL #2
LDR R6, [R6, #BgEcf] ; BgEcf for this scanline
10
STR R6, [R1], #4
SUBS R4, R4, #1
BNE %BT10
Pull R4
MOV PC, R14
; *****************************************************************************
;
; CreateSprite - Create a sprite with given attributes
;
; External routine
;
; in: R1 -> sprite area
; R2 -> sprite name
; R3 = 0/1 => exclude/include palette data
; R4 = width in pixels
; R5 = height in pixels
; R6 = mode number of sprite
;
CreateSprite ROUT
Push R14
KillSpChoosePtr
BL DeleteSpriteByName ; delete any existing sprite
STR R6, [WsPtr, #SGetMode] ; needs setting up before CreateHeader
SUB R6, R4, #1 ; width in pixels-1
SUB R7, R5, #1 ; height-1
MOV R4, #0
MOV R5, #0
; R3 ,R4,R5,R6,R7
BL CreateHeader ; In : Palette,sl,sb,sr,st
; Out: ImageSize
Pull PC, VS ; if error, then bomb out
MOV R4, #0 ; clear R3 words at offset 0 in sprite
BL ClearWords ; ie clear image to 0
; Now add the sprite to the sprite area
LDR R3, [R2, #spNext] ; total size of new sprite
LDMIA R1, {R4-R7} ; saEnd,saNumber,saFirst,saFree
ADD R5, R5, #1
ADD R7, R7, R3
STMIA R1, {R4-R7}
Pull R14
RETURNVC
; *****************************************************************************
;
; CreateHeader - Create a header and info for a sprite
;
; Internal routine, called by GetSprite, CreateSprite, ScreenSave
;
; in: R1 -> sprite area
; R2 -> sprite name
; R3 = 0/1 => exclude/include palette data
; R4,R5 = (X,Y) INTERNAL coordinate of bottom left
; R6,R7 = (X,Y) INTERNAL coordinate of top right
;
; out: R1 preserved
; R2 -> new sprite
; R3 = size of image in words
; R4,R5 = (X,Y) INTERNAL coordinate of top left of on screen area
; R0, R6-R11 corrupted
;
CreateHeader ROUT
Push "R1, R14"
Push R3
BL GetName ; name returned in R9-R11
ADD R8, WsPtr, #SGetName
STMIA R8, {R9-R11} ; save the name away
BL PreCreateHeader
Pull "R0, R1, PC", VS
; now the updating the sprite area bit
LDR R1, [R13, #1*4] ; reload sprite area ptr off stack
LDR R2, [R1, #saFree]
LDR R5, [R1, #saEnd]
SUB R5, R5, R2
CMP R5, R4
BCC %FT10
ADD R2, R2, R1 ; address of new sprite
PostCreateHeader
ADD R5, WsPtr, #SGetName
LDMIA R5, {R5-R11}
; R4 spNext, R5-R7 spName(0..2),
; R8 spWidth, R9 spHeight, R10 spLBit, R11 spRBit
STMIA R2, {R4-R11} ; write control block for sprite
LDR R11, [WsPtr, #SGetImage]
STR R11, [R2, #spImage]
STR R11, [R2, #spTrans] ; spImage=spTrans ie no mask
LDR R11, [WsPtr, #SGetMode]
STR R11, [R2, #spMode]
ANDS LR, R11, #15<<27 ; do we have an old or new sprite ?
BEQ %FT09
TEQ LR, #SpriteType_RISCOS5<<27 ; RISC OS 5 type?
[ NoARMT2
ANDEQ LR, R11, #127<<20
MOVEQ LR, LR, LSR #20
|
UBFXEQ LR, R11, #20, #7
]
MOVNE LR, LR, LSR #27
09
ADD R4, WsPtr, #SGetTopLeft
LDMIA R4, {R4, R5} ; (R4,R5) = TopLeft of 'on screen' area
Pull R11 ; R11 = 0/1 for (ex/in)clude palette
;amg 25th May 1994. We now allow palettes on new format sprites in 8bpp and below
CMP LR,#SpriteType_New16bpp
BCS %FT11 ; check for new 16/32 bpp
TEQ R11,#0 ; was a palette wanted in the first place?
BLNE WritePaletteToSprite ; do it if so
; ;only allow palette data to be written if EQ and R11<>0
;
; BNE %FT11
;
; TEQ R11, #0
; BLNE WritePaletteToSprite
11
Pull "R1, R14"
RETURNVC
10
ADRL R0, SpriteErr_NoRoom
[ International
BL TranslateError
]
STR R0, [WsPtr, #RetnReg0]
Pull "R0, R1, R14" ; junk palflag, sprite area ptr
RETURNVS
; *****************************************************************************
;
; SanitizeSGetMode - Convert SGetMode into a new format sprite word if necessary
;
; If SGetMode is either a) a mode selector pointer, or
; b) a mode number which has more than 8bpp
; then SGetMode is replaced by a suitable sprite mode word
;
; amg: 15/10/93: changed to be more keen to generate old format mode numbers. It is
; now also called from createsprite, so it will pass through a new
; sprite mode word unchanged. Mode numbers will be unchanged. Mode
; selectors will be changed to a mode number if one of suitable
; eigs and depth exists --- size of screen is *not* taken into
; account here.
; in: WsPtr -> VDU workspace
;
; out: If OK, then
; V=0
; All registers preserved
; else
; V=1
; r0 -> error
; RetnReg0 -> error
; endif
;
SanitizeSGetMode Entry "r0-r4,r11"
LDR r11, [WsPtr, #SGetMode]
CMP r11, #&100
BCC %FT20 ; [not a mode selector or new format sprite word]
TST r11, #1 ; is it already a new format sprite word?
EXIT NE
10
MOV r0, r11 ; r0 -> mode selector
[ ModeSelectors
BL ValidateModeSelector
STRVS r0, [sp]
STRVS r0, [WsPtr, #RetnReg0]
EXIT VS
]
15
; convert to new format sprite word
MOV r4, r11 ; preserve the mode for later
;amg: add check for log2bpp=log2bpc
MOV r0, r4
MOV r1, #VduExt_Log2BPC
SWI XOS_ReadModeVariable
MOV R3,R2
MOV r0, r4
MOV r1, #VduExt_Log2BPP
SWI XOS_ReadModeVariable
CMP R3, R2
BNE %FT90
MOV r0, r4
MOV r1, #VduExt_ModeFlags
SWI XOS_ReadModeVariable
MOV r3, r2
MOV r0, r4
MOV r1, #VduExt_NColour
SWI XOS_ReadModeVariable
; work out the sprite type. Note: Only dealing with RGB colour space here!
ADDS r2, r2, #1
MOVEQ r11, #SpriteType_New32bpp
BEQ %FT16
CMP r2, #1<<24
MOVEQ r11, #SpriteType_New24bpp
BEQ %FT16
CMP r2, #1<<12
MOVEQ r11, #SpriteType_New4K
BEQ %FT16
CMP r2, #1<<1
MOVEQ r11, #SpriteType_New1bpp
BEQ %FT16
CMP r2, #1<<2
MOVEQ r11, #SpriteType_New2bpp
BEQ %FT16
CMP r2, #1<<4
MOVEQ r11, #SpriteType_New4bpp
BEQ %FT16
CMP r2, #1<<8
CMPNE r2, #1<<6
MOVEQ r11, #SpriteType_New8bpp
BEQ %FT16
CMP r2, #1<<16
BNE %FT90
; Could be 565 or 1555
TST r3, #ModeFlag_64k
MOVEQ r11, #SpriteType_New16bpp
MOVNE r11, #SpriteType_New64K
16
; work out whether we need a RISC OS 5 mode word or not
ANDS r3, r3, #ModeFlag_DataFormat_Mask ; Any relevant modeflags set?
TSTEQ r11, #&F0 ; Type too big for 4 bits?
BEQ %FT17
; RISC OS 5 style sprite mode word
ORR r11, r3, r11, LSL #20 ; sprite type plus mode flags
ORR r11, r11, #1 + (SpriteType_RISCOS5<<27)
MOV r1, #VduExt_XEigFactor
SWI XOS_ReadModeVariable
ORR r11, r11, r2, LSL #4 ; put xdpi into position
MOV r1, #VduExt_YEigFactor
SWI XOS_ReadModeVariable
ORR r11, r11, r2, LSL #6 ; put ydpi into position
STR r11, [WsPtr, #SGetMode] ; store new value
EXIT
17
; "New"-style sprite mode word
MOV r11, r11, LSL #27
ORR r11, r11, #1
MOV r1, #VduExt_XEigFactor
SWI XOS_ReadModeVariable
MOV lr, #180
MOV lr, lr, LSR r2 ; cope with 45, 90, 180 dpi
ORR r11, r11, lr, LSL #1 ; put into xdpi position
MOV r1, #VduExt_YEigFactor
SWI XOS_ReadModeVariable
MOV lr, #180
MOV lr, lr, LSR r2
ORR r11, r11, lr, LSL #14 ; put into ydpi position
STR r11, [WsPtr, #SGetMode] ; store new value
;now check if we can force it back to a mode number
;if the bpp is > 8 the answer is no
AND r2, r11, #15<<27
CMP r2, #SpriteType_New16bpp
EXIT CS
BIC r0, r11, #&F8000000 ; take off the type information
ADR r1, substitute_list
ADD r2, r1, #12 ; end of list
27
LDR r3, [r1], #4
TEQ r3, r0
BEQ %FT28
TEQ r1, r2
EXIT EQ ; can't do anything with it
BNE %BT27
28
ADD r1, r1, #8 ; point at modes word, allowing for post inc
ADD r1, r1, r11, LSR #27 ; add in the sprite's type
SUB r1, r1, #1 ; and reduce it by one
LDRB r1, [r1] ; fetch the right mode number
;if we got 255, we can't save the day
CMP r1,#255
STRNE r1, [WsPtr, #SGetMode] ; and store it
EXIT
substitute_list
DCD &001680B5 ;90 X 90 DPI, X/Y EIG 1 1
DCD &000B40B5 ;90 X 45 DPI, X/Y EIG 1 2
DCD &000B405B ;45 X 45 DPI, X/Y EIG 2 2
;amg: used to use mode 4 for 2 colour eig 2 x 2 - now doesn't because of
;confusion about double pixels
DCD &1C1B1A19 ;modes 25, 26, 27, 28 for 90 x 90
DCD &0F0C0800 ;modes 0, 8, 12, 15 for 90 x 45
DCD &0D0901FF ;modes n/a, 1, 9, 13 for 45 x 45
20
MOV r0, r11 ; check if bpp for mode is > 8
MOV r1, #VduExt_Log2BPP
SWI XOS_ReadModeVariable
CMP r2, #4
BCS %BT15 ; if so then convert to new format sprite as well
EXIT
90
ADRL R0, ErrorBlock_BadMODE
[ International
BL TranslateError
]
STR r0, [sp]
STR r0, [WsPtr, #RetnReg0]
SETV
EXIT
; *****************************************************************************
PreCreateHeader ROUT
Push R14
BL SanitizeSGetMode ; convert SGetMode to new format sprite if nec.
Pull PC, VS ; duff mode selector
;amg 25th May 1994
;We now allow palettes on new format sprites of 8bpp and below
; ;force to no palette space if a new format sprite
; LDR LR, [WsPtr, #SGetMode] ; get the mode
; MOVS LR, LR, LSR #27 ; set NE if new
; MOVNE R3, #0 ; turn off palette
LDR LR, [WsPtr, #SGetMode] ; get the sprite mode word
BIC LR, LR, #&80000000 ; ignore alpha mask flag
CMP LR, #SpriteType_RISCOS5<<27
MOVLO LR, LR, LSR #7 ; shift sprite type to its RISC OS 5 location
ANDHS LR, LR, #127<<20 ; or get RISC OS 5 type as-is
CMP LR, #SpriteType_New16bpp<<20 ; check for true colour
MOVHS R3, #0 ; turn off the palette request
TEQ R3, #0 ; convert R3 into mask to (ex/in)clude
MOVNE R3, #&FF ; space for palette data
; amg need more palette space in case it's going to be a full palette
ORRNE R3, R3, #&300
Push "R6, R7" ; preserve R6,R7 over the call
ADD R2, WsPtr, #SGetNext
BL SetupSprModeData
; R6 ,R7 ,R8 ,R9 ,R10 ,R11
; Out: RdNCol,WrNCol,BytePC,XShft,NPix,Log2BPC
; amg 26th October 1993 - kill another bit of Arthur compatibility in favour
; of full palette 8bpp sprites
; AND R6, R6, #63 ; make 64 palette entries like MOS 1.2
LDR R7,[WsPtr,#ModeFlags]
TST R7, #ModeFlag_FullPalette
ANDEQ R6, R6, #63
ADD R6, R6, #1 ; number of palette entries in this mode
AND R3, R3, R6 ; if (palette not wanted) OR (256 colour mode)
; then R3=0 else R3=number of palette entries
; N.B. in 256 colour modes we end up ignoring
; the palette
Pull "R6,R7"
Pull PC, VS ; error, not a graphics mode
MOV R3, R3, LSL #3 ; two words per palette entry
ADD R3, R3, #SpriteCBsize
STR R3, [WsPtr, #SGetImage] ; R0-R3 now free for use
; R4 ,R5, R6 ,R7
; sL ,sB, sR ,sT
SUB R0, R7, R5 ; height-1
STR R0, [WsPtr, #SGetHeight]
ADD R0, R0, #1 ; actual height in rows
LDR R1, [WsPtr, #GWTRow] ; if SpriteTopRow > GWTopRow
SUBS R2, R7, R1
MOVGT R7, R1 ; then clip for ScreenAddr's benefit
MOVLE R2, #0
Least R2, R2, R0
STR R2, [WsPtr, #SGetTopMargin] ; number of blank rows at top
LDR R1, [WsPtr, #GWBRow]
SUBS R2, R1, R5
MOVLT R2, #0
Least R2, R2, R0
STR R2, [WsPtr, #SGetBotMargin] ; number of blank rows at bottom
WordOffset R0,R4, R9,R10,R11 ; offset to sL
WordOffset R1,R6, R9,R10,R11 ; to sR
SUB R2, R1, R0 ; width-1
STR R2, [WsPtr, #SGetWidth]
ADD R2, R2, #1 ; actual width in words
BitLOffset R3,R4, R9,R10,R11 ; LBit
STR R3, [WsPtr, #SGetLBit]
BitROffset R3,R6, R9,R10,R11 ; RBit
STR R3, [WsPtr, #SGetRBit]
LDR R8, [WsPtr, #GWLCol]
Greatest R4,R4,R8
WordOffset R3,R4, R9,R10,R11 ; offset to clipL
SUB R3, R3, R0
Least R3,R3,R2
STR R3, [WsPtr, #SGetLWrdMargin] ; no. of blank words at left
BitLOffset R3,R4, R9,R10,R11
STR R3, [WsPtr, #SGetLBitMargin] ; no. of blank words at right
LDR R8, [WsPtr, #GWRCol]
Least R6, R6, R8
WordOffset R3,R6, R9,R10,R11 ; offset to clipR
SUB R3, R1, R3
Least R3, R3, R2
STR R3, [WsPtr, #SGetRWrdMargin]
BitROffset R3,R6, R9,R10,R11
STR R3, [WsPtr, #SGetRBitMargin]
ADD R0, WsPtr, #SGetTopLeft
STMIA R0, {R4, R7} ; store top & left of 'on screen' area
LDR R0, [WsPtr, #SGetWidth]
LDR R1, [WsPtr, #SGetHeight]
ADD R0, R0, #1 ; width in words
ADD R1, R1, #1 ; height in words
MUL R3, R1, R0 ; image size in words
LDR R4, [WsPtr, #SGetImage]
ADD R4, R4, R3, LSL #2 ; total size in bytes
Pull R14
RETURNVC
; *****************************************************************************
;
; Decide mask size
;
; Internal routine called from CreateMask
;
; in: R1 -> sprite area
; R2 -> sprite
; R3 = size of image data (bytes)
;
; out: R3 = size of mask data (words)
DecideMaskSize ROUT
Entry "R5,R8"
LDR LR, [R2, #spMode] ; get the sprite mode
MOVS LR, LR, LSR #27 ; isolate the type
MOVEQ R3,R3,LSR #2 ; if T=0 then return the same size as
EXIT EQ ; the image (but returns in words not
; bytes)
LDR R5, [R2, #spWidth]
BL GetMaskspWidth ; get mask width information
LDR LR, [R2, #spHeight] ; number of rows (minus 1)
ADD R5, R5, #1 ; width in words
ADD LR, LR, #1 ; height in rows
MUL R3, LR, R5 ; number of words for the mask
EXIT
; *****************************************************************************
;
; CreateMask - Add mask to sprite or set existing mask to 'solid'
;
; External routine
;
; in: R1 -> sprite area
; R2 -> sprite
;
CreateMask ROUT
Push R14
KillSpChoosePtr
LDR R4, [R2, #spNext]
LDR R5, [R2, #spImage] ; NB Image=Trans if NO mask
LDR R6, [R2, #spTrans]
SUB R3, R4, R6
BL DecideMaskSize ; returns R3=size of mask (words)
TEQ R5, R6
BNE %FT10 ; mask exists
MOV R6, R4
BL ExtendSprite
ADRVSL R0, SpriteErr_NotEnoughRoom ; only error is NoRoomToInsert
[ International
BLVS TranslateError
]
STRVS R0, [WsPtr, #RetnReg0] ; correct this to 'Not enough room'
Pull PC, VS
STR R6, [R2, #spTrans] ; new spTrans := old spNext
10 ; R3 mask size (words), R6 spTrans
ADD R6, R6, R2
MOV R4, #&FFFFFFFF
20
STR R4, [R6], #4
SUBS R3, R3, #1
BNE %BT20
Pull R14
RETURNVC
; *****************************************************************************
;
; RemoveMask - Remove mask from sprite
;
; External routine
;
; in: R1 -> sprite area
; R2 -> sprite
;
RemoveMask ROUT
Push R14
KillSpChoosePtr
LDR R4, [R2, #spNext]
LDR R5, [R2, #spImage] ; NB spTrans = spImage, if NO mask
LDR R6, [R2, #spTrans]
TEQ R5, R6
BEQ %FT10 ; no mask so ignore
SUB R3, R4, R6
BL DecideMaskSize ; returns R3=size in words
SUB R4, R6, R5
BL RemoveWords
LDR R5, [R2, #spImage] ; spTrans := spImage, ie NO mask
STR R5, [R2, #spTrans]
10
Pull R14
RETURNVC
; *****************************************************************************
;
; WritePaletteToSprite - Write palette information into sprite CB
;
; Internal routine, called by CreateHeader
;
; in: R2 -> sprite
;
; out: All registers preserved
;
WritePaletteToSprite ROUT
Push "R0-R4, R14"
LDR R0, [WsPtr, #SprReadNColour] ; highest palette entry
; amg 26th October 1993 - this bit of Arthur compatibility bites the
; dust to make screensaving full palette sprites work properly
; AND R0, R0, #63 ; make 63 if 255 like MOS 1.20
LDR R4, [WsPtr,#ModeFlags]
TST R4, #ModeFlag_FullPalette
ANDEQ R0, R0, #63
ADD R4, R2, R0, LSL #3
ADD R4, R4, #spPalette ; ptr to last pal pos in spPalette
10
MOV R1, #16 ; read 'normal' colour
SWI XOS_ReadPalette
STMIA R4, {R2,R3}
SUB R4, R4, #8
SUBS R0, R0, #1
BCS %BT10
Pull "R0-R4,PC"
; *****************************************************************************
;
; WritePaletteFromSprite - Write palette from information in sprite CB
;
; Internal routine, called by ScreenLoad
;
; in: R2 -> sprite
;
; out: All registers preserved
;
WritePaletteFromSprite ROUT
Push "R0-R6, R14"
LDR R0, [WsPtr, #ModeNo]
LDR R1, [R2, #spMode]
[ {TRUE} :LAND: ModeSelectors
;logic for this routine
;
;[WsPtr, #ModeNo] is the current mode/ptr to mode selector
;R2 points at sprite data
;[WsPtr, #SloadModeSel] is 36 bytes for building a mode selector for the sprite
;
;sprite mode < 256 ?
;yes: equal to current mode ?
; yes: already in correct mode. done.
; no: change to mode sprite wants, done.
;no: build a mode selector for the sprite
; check pixel depth, xres, yres, xdpi and ydpi
; all identical ?
; yes: already in suitable mode. done.
; no: change mode. done.
;if we do a mode change, remember to re-remove cursors
;amg 15 Oct '93 Screensave is about to be changed to use a representative
;mode number of the eigs and depth (only), so screenload no longer believes
;the screen mode number in the file.
;amg 21 Dec '93 Slight modification - if the screen mode change failed, and
;we have an old screen mode number, use that as a last gasp
; CMP R1, #256
; BCS %FT30 ;branch if a new format sprite mode word
; CMP R1, R0 ;are we in the right (old style) mode ?
; BEQ %FT10
; MOV R0,#ScreenModeReason_SelectMode
; SWI XOS_ScreenMode
; STRVS R0, [WsPtr, #RetnReg0] ;exit on error
; Pull "R0-R6,PC", VS
; B %FT40 ;otherwise get on with it
30 ; new format sprite mode word
; build the mode selector at SLoadModeSel
MOV R5, R1 ;keep the mode number/sprite mode word safe
;do the absolutes first
MOV R3, #-1
STR R3, [WsPtr, #SloadModeSel+ModeSelector_FrameRate]
STR R3, [WsPtr, #SloadModeSel+ModeSelector_ModeVars+16] ;list terminator after two pairs
STR R3, [WsPtr, #SloadModeSel+ModeSelector_ModeVars+32] ;list terminator after four pairs
MOV R3, #128
STR R3, [WsPtr, #SloadModeSel+ModeSelector_ModeVars+20] ;modeflags value, if needed
MOV R3, #VduExt_NColour
STR R3, [WsPtr, #SloadModeSel+ModeSelector_ModeVars+24]
MOV R3, #255
STR R3, [WsPtr, #SloadModeSel+ModeSelector_ModeVars+28]
MOV R3, #1
STR R3, [WsPtr, #SloadModeSel+ModeSelector_Flags]
MOV R3, #VduExt_XEigFactor
STR R3, [WsPtr, #SloadModeSel+ModeSelector_ModeVars] ; modevar 1 = xeig
MOV R3, #VduExt_YEigFactor
STR R3, [WsPtr, #SloadModeSel+ModeSelector_ModeVars+8] ; modevar 2 = Yeig
;now the things from the sprite
; MOV R3, R1, LSR #27 ;sprite type
; ADRL R4, NSM_bpptable-4 ;readmodevar's table
; LDR R3, [R4, R3, LSL #2] ;word index
; STR R3, [WsPtr, #SloadModeSel+ModeSelector_PixelDepth]
;change to calling read mode variable to cope with mode number or sprite mode word
MOV R4, R2 ;save the sprite pointer
MOV R0, R5 ;sprite mode word/mode number
MOV R1, #VduExt_Log2BPP
SWI XOS_ReadModeVariable
STR R2, [WsPtr, #SloadModeSel+ModeSelector_PixelDepth]
MOV R3, R2
;if log2bpp=3, and size of palette data indicates full palette, we need to force
;a suitable mode
CMP R3, #3
BNE %FT40
ADD LR, R4, #spImage ;point to image/mask start
LDMIA LR,{R2,LR} ;fetch them
CMP R2,LR ;which is bigger ?
MOVGT R2,LR ;use the least
SUB R2,R2,#spPalette ;and the palette size is...
CMP R2,#&800 ;full entry 256 colour
;change the mode selector so it includes a modeflags word
;(following two words already set up)
MOVEQ R2, #0
;amg 28/4/94 bugfix - following inst wasn't conditional
STREQ R2, [WsPtr, #SloadModeSel+ModeSelector_ModeVars+16]
40
MOV R2, R4 ;restore the sprite pointer
LDR R4, [R2, #spWidth] ;number of words
MOV R4, R4, LSL #5 ;convert to a number of bits
LDR LR, [R2, #spRBit] ;last bit used
ADD LR, LR, #1 ;convert to number of bits
ADD R4, R4, LR ;combine
MOV R4, R4, LSR R3 ;and convert to pixels
STR R4, [WsPtr, #SloadModeSel+ModeSelector_XRes]
LDR R3, [R2, #spHeight]
ADD R3, R3, #1
STR R3, [WsPtr, #SloadModeSel+ModeSelector_YRes]
MOV R6, R2 ;save the sprite pointer for later
;that leaves the x and y eig factors, which are derived
;from the dpi
MOV R0, R5 ;R0 = sprite mode word
MOV R1, #VduExt_XEigFactor
SWI XOS_ReadModeVariable
STRCC R2, [WsPtr, #SloadModeSel+ModeSelector_ModeVars+4]
MOVCC R1, #VduExt_YEigFactor
SWICC XOS_ReadModeVariable
STRCC R2, [WsPtr, #SloadModeSel+ModeSelector_ModeVars+12]
BCS %FT90 ;we canna take it captain....
;do the comparison which involve the mode selectors first
;depth
LDR LR, [WsPtr, #ModeNo]
LDR R3, [LR, #ModeSelector_PixelDepth]
LDR R4, [WsPtr, #SloadModeSel+ModeSelector_PixelDepth]
TEQ R3, R4
BNE %FT80 ;need to change mode to new mode selr
LDR R3, [LR, #ModeSelector_XRes]
LDR R4, [WsPtr, #SloadModeSel+ModeSelector_XRes]
TEQ R3, R4
BNE %FT80 ;need to change mode to new mode selr
LDR R3, [LR, #ModeSelector_YRes]
LDR R4, [WsPtr, #SloadModeSel+ModeSelector_YRes]
TEQ R3, R4
BNE %FT80 ;need to change mode to new mode selr
;now the eigs
LDR R3, [WsPtr, #XEigFactor]
LDR R4, [WsPtr, #SloadModeSel+ModeSelector_Flags+4]
TEQ R3, R4
BNE %FT80 ;need to change mode to new mode selr
LDR R3, [WsPtr, #YEigFactor]
LDR R4, [WsPtr, #SloadModeSel+ModeSelector_Flags+12]
TEQ R3, R4
BEQ %FT10 ;this mode is suitable
80
MOV R0,#ScreenModeReason_SelectMode
ADD R1,WsPtr,#SloadModeSel
SWI XOS_ScreenMode
[ {TRUE}
;ensure we preserve the error pointer in situations where we can't try to
;fall back to the mode number in the sprite header
;if it errored try again if there's a mode number available
BVC %FT40
LDR R1, [R6, #spMode]
BICS R14, R1, #&FF ; EQ if sprite mode is a number (< 256), (V still set afterwards)
MOVEQ R0, #ScreenModeReason_SelectMode
SWIEQ XOS_ScreenMode ; if called, will set V appropriately
|
;if it errored try again if there's a mode number available
BVC %FT40
MOV R0, #ScreenModeReason_SelectMode
LDR R1, [R6, #spMode]
BICS R14, R1, #&FF ; EQ if sprite mode is a number (< 256), (V still set afterwards)
SWIEQ XOS_ScreenMode ; if called, will set V appropriately
]
STRVS R0, [WsPtr, #RetnReg0] ;exit on error
Pull "R0-R6,PC", VS
B %FT40 ;otherwise get on with it
90
ADRL R0,SpriteErr_InvalidSpriteMode
[ International
BL TranslateError
|
SETV
]
STR R0, [WsPtr, #RetnReg0]
Pull "R0-R6,PC"
|
;as originally done this code tended to compare mode specifiers against new
;sprite mode words, and worse still tried to select a mode from a new sprite
;mode word. the rewrite above takes a more logical approach
CMP R0, R1 ; if already in correct mode
BEQ %FT10 ; then skip
[ ModeSelectors
MOV r0, #ScreenModeReason_SelectMode
SWI XOS_ScreenMode
|
MOV R0, #22
SWI XOS_WriteC
MOVVC R0, R1
SWIVC XOS_WriteC
]
STRVS R0, [WsPtr, #RetnReg0]
Pull "R0-R6,PC", VS
]
40
SWI XOS_RemoveCursors ; remove cursors again
10
MOV R2, R6
LDR R3, [R2, #spImage]
CMP R3, #spPalette ; will clear V if EQ
Pull "R0-R6, PC", EQ ; no palette data
LDR R4, [WsPtr, #NColour]
ADD R3, R2, #spPalette
ADD R3, R3, R4, LSL #3
20
LDMIA R3, {R1,R2}
MOV R0, R4
BL SendPalettePair
Pull "R0-R6, PC", VS
SUB R3, R3, #8
SUBS R4, R4, #1 ; (V will be cleared by this)
BCS %BT20
Pull "R0-R6, PC"
; *****************************************************************************
;
; SendPalettePair - Program palette with flash pair
;
; Internal routine, called by WritePaletteFromSprite
;
; in: R0 = logical colour
; R1 = first flash colour
; R2 = second flash colour
;
; out: R1 corrupted
;
SendPalettePair ROUT
Push "R0-R3, R14"
TEQ R1, R2 ; are colours the same ?
BNE %FT10 ; if not then do in two halves
MOV R3, #16
BL SendPaletteEntry ; then send with 16
Pull "R0-R3, PC"
10
MOV R3, #17 ; else send 1st flash with 17
BL SendPaletteEntry
MOVVC R1, R2
MOVVC R3, #18 ; then 2nd flash with 18
BLVC SendPaletteEntry
Pull "R0-R3, PC"
; *****************************************************************************
;
; SendPaletteEntry - Program one palette entry
;
; Internal routine, called by SendPalettePair
;
; in: R0 = logical colour
; R1 = physical colour BGRx
; R3 = PP field to use
;
; out: All registers preserved
;
SendPaletteEntry ROUT
Push "R0,R1, R14"
BIC R1, R1, #&7F ; clear all bits except sup. bit
ORR R1, R1, R3 ; or in new bits
MOV R0, R0, LSL #24 ; move log. col. up to top 8 bits
Push "R0, R1" ; create an OSWORD block at R13+3
MOV R0, #12
ADD R1, R13, #3 ; R1 -> block
SWI XOS_Word
STRVS R0, [WsPtr, #RetnReg0]
ADD R13, R13, #8
Pull "R0,R1, PC"
END