; 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.
;
; > Sources.SprAdjSize
;;----------------------------------------------------------------------------
;; AdjustManyRows or Columns
;;----------------------------------------------------------------------------
MakeSpriteErrorBlock InvalidRowOrCol,,InvRC
MakeSpriteErrorBlock NoRoomToInsert,,NoIRoom
input_out_of_range
ADR R0, ErrorBlock_InvalidRowOrCol
addr r1, Title
BL copy_error_one ; Always sets the V bit
Pull "R1-R11,PC"
no_room_to_insert
ADR R0, ErrorBlock_NoRoomToInsert
addr r1, Title
BL copy_error_one ; Always sets the V bit
Pull "R1-R11,PC"
; ----------------------------------------------------------
Go_InsertDeleteRows
Push "R1-R11,R14"
Debug id,"Entry:",R3,R4
;
; see if reason code indicated a sprite name or sprite pointer in R2
BLVC findsprite ; R2 --> sprite
Pull "R1-R11,PC",VS
;
; Check for insertion/deletion
;
CMP R4, #0
Pull "R1-R11,PC",EQ
BMI delete_many_rows
B insert_many_rows
; ----------------------------------------------------------
delete_many_rows
; Updated to work with new format sprites
;
; Check that the call is trying to start deleting at a row inside the sprite
RSB R4, R4, #0
CMP R3, #0
BLT input_out_of_range
LDR R6, [R2, #spHeight]
ADD R6, R6, #1
CMP R3, R6
BGE input_out_of_range
;
; Check that the call is trying to finish deleting at a row inside the sprite
ADD R3, R3, R4
SUBS R3, R3, #1
BMI input_out_of_range
CMP R3, R6
BGE input_out_of_range
;
; Check for all rows being deleted
CMP R4, R6
BGE input_out_of_range
LDR R5, [R2, #spWidth] ; R5 = sprite width (in words)
ADD R5, R5, #1
MOV R5, R5, LSL #2 ; in bytes
MUL R0, R4, R5 ; Get length of block to delete
LDR R7, [R2, #spImage] ; Get offset to image R7, and mask R8
LDR R8, [R2, #spTrans]
Debug id,"In range. Details are: (W,H,I,T,size,start)",R5,R6,R7,R8,R0,R3
; Now check for mask
CMP R7, R8 ; If they're the same then there is no mask
BEQ deleting_rows_no_mask
;
; Delete the mask rows
;First, are we new or old format?
LDR R9, [R2, #spMode]
MOVS R9, R9, LSR #27
BEQ %FT10
LDR R5, [R2, #spWidth] ; R5 = mask width - 1 (in words)
Push R8
BL GetMaskspWidth ; Change it 'cos we're new format
Pull R8
ADD R5, R5, #1
MOV R5, R5, LSL #2 ; mask row width in bytes
MUL R0, R4, R5 ; Get length of block to delete
10 SUB R9, R6, R3 ; Get address of starting row (from top of sprite)
SUB R9, R9, #1
MUL R9, R5, R9
ADD R9, R2, R9 ; Add to mask start
ADD R9, R8, R9
LDR R10, [R1, #saFree] ; Get address of last word to move down
ADD R10, R10, R1
BL move_memory_down ; Move the memory from [R9+R0 to R10] down to [R9 to R10-R0]
;
; Account for loss of mask rows in the sprite area block and sprite block
LDR R9, [R1, #saFree] ; Move the 'free space' pointer back by size deleted in bytes
SUB R9, R9, R0
STR R9, [R1, #saFree]
LDR R9, [R2, #spNext] ; Move offset to next sprite back by size in bytes
SUB R9, R9, R0
STR R9, [R2, #spNext]
;Finally redo our R5 stuff
LDR R5, [R2, #spWidth] ; R5 = sprite width (in bytes)
ADD R5, R5, #1
MOV R5, R5, LSL #2 ; in bytes
MUL R0, R4, R5 ; Get length of block to delete
;
; Delete the image rows
deleting_rows_no_mask
SUB R9, R6, R3 ; Get address of starting row (from top of sprite)
SUB R9, R9, #1
MUL R9, R5, R9
ADD R9, R2, R9 ; Add to image start
ADD R9, R7, R9
LDR R10, [R1, #saFree] ; Get address of last word to move down
ADD R10, R10, R1
BL move_memory_down ; Move the memory from [R9+R0 to R10] down to [R9 to R10-R0]
;
; Account for loss of mask rows in the sprite area block and sprite block
LDR R9, [R1, #saFree] ; Move the 'free space' pointer back by size deleted in bytes
SUB R9, R9, R0
STR R9, [R1, #saFree]
CMP R7, R8 ;Only change the ptr if there is a mask
LDRNE R8, [R2, #spTrans] ; Move the mask pointer back by size in bytes
SUBNE R8, R8, R0
STRNE R8, [R2, #spTrans]
LDR R9, [R2, #spNext] ; Move offset to next sprite back by size in bytes
SUB R9, R9, R0
STR R9, [R2, #spNext]
;
; Remove rows from data
Debug id, "Height, delta",R6,R4
SUB R6, R6, #1
SUB R6, R6, R4
STR R6, [R2, #spHeight]
;
; Exit
CLRV
Pull "R1-R11,PC"
; ----------------------------------------------------------
insert_many_rows
; Updated to work with new format sprites
;
; Check that the call is trying to start inserting at a row inside the sprite
CMP R3, #0
BLT input_out_of_range
LDR R6, [R2, #spHeight] ; R6 = sprite height
ADD R6, R6, #1
CMP R3, R6
BGT input_out_of_range
;
LDR R5, [R2, #spWidth] ; R5 = sprite width (in bytes)
ADD R5, R5, #1
MOV R5, R5, LSL #2 ; in bytes
MUL R0, R4, R5 ; Get length of block to insert
LDR R7, [R2, #spImage] ; Get offset to image R7, and mask R8
LDR R8, [R2, #spTrans]
LDR R9, [R1, #saFree] ; Check that the end of the block after insertion
ADD R9, R9, R0
CMP R7, R8 ; (allowing for mask)
BEQ little_skip
LDR R10, [R2, #spMode]
MOVS R10, R10, LSR #27
ADDEQ R9, R9, R0 ; Old format, so sprite is same size as image
BEQ little_skip
Push R5 ;New format, so we need a quick conversion
LDR R5, [R2, #spWidth]
Push R8
BL GetMaskspWidth
Pull R8
ADD R5, R5, #1
MOV R5, R5, LSL #2
MUL R10, R4, R5
ADD R9, R9, R10
Pull R5 ;End of quick conversion
little_skip
LDR R10, [R1, #saEnd] ; is before the end of the block
CMP R9, R10
BGT no_room_to_insert
Debug id,"In range. Details are: (W,H,I,T,size,start)",R5,R6,R7,R8,R0,R3
;
; Now check for mask
CMP R7, R8 ; If they're the same then there is no mask
BEQ inserting_rows_no_mask
;
; Insert the mask rows
; Debug ag,"Eh up, we've got a mask"
;First, are we a new or old format sprite?
LDR R9, [R2,#spMode]
MOVS R9, R9, LSR #27
; DebugIf NE,ag,"And it's a new format one at that!"
BEQ %FT10
LDR R5, [R2, #spWidth]
; DebugIf NE,ag,"Image width-1 (words) is ",R5
Push R8
BL GetMaskspWidth ;Convert it to 1bpp values (words)
Pull R8
; DebugIf NE,ag,"Mask (1bpp) width-1 (words) is now ",R5
ADD R5, R5, #1
MOV R5, R5, LSL #2 ;(bytes)
MUL R0, R4, R5
10
; Debug ag,"The grand total of bytes to be moved up by is ",R0
SUB R9, R6, R3 ; Get address of starting row (from top of sprite)
MUL R9, R5, R9
ADD R9, R2, R9 ; Add to mask start
ADD R9, R8, R9
; Debug ag,"Moving from ",R9
LDR R10, [R1, #saFree] ; Get address of last word to move down
ADD R10, R10, R1
; Debug ag,"Moving amount ",R10
BL move_memory_up ; Move the memory from [R9 to R10] up to [R9+R0 to R10+R0]
;
; Account for gain of mask rows in the sprite area block and sprite block
LDR R9, [R1, #saFree] ; Move the 'free space' pointer forward by size inserted in bytes
ADD R9, R9, R0
STR R9, [R1, #saFree]
LDR R9, [R2, #spNext] ; Move offset to next sprite forward by size in bytes
ADD R9, R9, R0
STR R9, [R2, #spNext]
;Finally redo our R5 stuff
LDR R5, [R2, #spWidth] ; R5 = sprite width (in bytes)
ADD R5, R5, #1
MOV R5, R5, LSL #2 ; in bytes
MUL R0, R4, R5 ; Get length of block to delete
; Debug ag,"After the rehash of R5, it is (bytes) ",R5
; Debug ag,"and the amount to be moved by is ",R0
;
; Insert the image rows
inserting_rows_no_mask
SUB R9, R6, R3 ; Get address of starting row (from top of sprite)
MUL R9, R5, R9
ADD R9, R2, R9 ; Add to image start
ADD R9, R7, R9
LDR R10, [R1, #saFree] ; Get address of last word to move up
ADD R10, R10, R1
BL move_memory_up ; Move and clear the memory from [R9 to R10] up to [R9+R0 to R10+R0]
;
; Account for loss of mask rows in the sprite area block and sprite block
LDR R9, [R1, #saFree] ; Move the 'free space' pointer forward by size deleted in bytes
ADD R9, R9, R0
STR R9, [R1, #saFree]
CMP R7, R8
LDRNE R8, [R2, #spTrans] ; Move the mask pointer forward by size in bytes
ADDNE R8, R8, R0
STRNE R8, [R2, #spTrans]
LDR R9, [R2, #spNext] ; Move offset to next sprite forward by size in bytes
ADD R9, R9, R0
STR R9, [R2, #spNext]
;
; Add rows to data
Debug id, "Height, delta",R6,R4
SUB R6, R6, #1
ADD R6, R6, R4
STR R6, [R2, #spHeight]
;
; Exit
CLRV
Pull "R1-R11,PC"
; ----------------------------------------------------------
Go_InsertDeleteColumns
Push "R1-R11,R14"
Debug id,"Entry:",R3,R4
;
; see if reason code indicated a sprite name or sprite pointer in R2
BLVC findsprite ; R2 --> sprite
Pull "R1-R11,PC",VS
;
; Check for insertion/deletion
;
CMP R4, #0
Pull "R1-R11,PC",EQ
BMI delete_many_columns
B insert_many_columns
; ----------------------------------------------------------
delete_many_columns
; Updated to work with new format sprites
;
; Check that the call is trying to start deleting at a column inside the sprite
RSB R4, R4, #0
CMP R3, #0
BLT input_out_of_range
;
; Get log2bpp for the sprite
Push "R1-R2"
LDR R0, [R2, #spMode]
MOV R1, #VduExt_Log2BPP
SWI XOS_ReadModeVariable
Debug id,"Read mode variable log2bpp for mode:",R2,R0
;unknown modes will return CS. It's not safe to proceed from here,
;so exit.
SETV CS
MOVVC R5, R2
Pull "R1-R2"
Pull "R1-R11,PC",VS
Push "R3-R5" ; We'll want these later...
;
; Make R3 = left bit to delete, R4 = right bit to delete (if deleting zeroth column
; then also delete left-hand wastage
ADD R4, R3, R4
MOV R3, R3, LSL R5 ; R3 = left-bit of column to delete
MOV R4, R4, LSL R5 ; R4 = right-bit
SUB R4, R4, #1
LDR R5, [R2, #spLBit] ; Account for left-hand wastage
CMP R3, #0 ; (but only for R3 if it is non-zero)
ADDNE R3, R3, R5
ADD R4, R4, R5
Debug id, "Deleting from bit to bit ",R3,R4
;
; Check that the call is trying to finish deleting at a column inside the sprite
LDR R5, [R2, #spWidth] ; Get number of bits to be deleted after the
SUB R5, R4, R5, LSL #5 ; start of the last word in each sprite row
LDR R6, [R2, #spRBit] ; If it is greater than the last bit used then
CMP R5, R6 ; an attempt is being made to delete past
Pull "R3-R5",GT
BGT input_out_of_range ; the end of the sprite row
BLT not_deleting_rhcolumn
; Check for all columns being deleted
CMP R3, #0
Pull "R3-R5",EQ
BEQ input_out_of_range
; NOTE: The following commented-out chunk of code appears to be superfluous. If preceded by
; a CMP R5,R6 (which might be the expected intention), the routine breaks, messing up when the
; deleted columns include the leftmost column (ie 0). It is left in the source purely to prevent
; someone putting it back in. WT
; RSBEQ R6, R6, #31 ; If it is equal (i.e. deleting the last column)
; ADDEQ R4, R4, R6 ; then delete the right-hand wastage too
; MOVEQ R6, #31 ; And set RHwastage = 0, for deletion
; STREQ R6, [R2, #spRBit]
not_deleting_rhcolumn
Debug id, "Deleting from bit to bit ",R3,R4
;
; Okay, now to delete the bits from R3 to R4 in both the image (and the mask)
;
; Delete the columns from the mask
LDR R6, [R2, #spTrans] ; Check there is a mask
LDR R7, [R2, #spImage]
CMP R6, R7
BEQ %FT99 ;Branch if no mask
;Ok, so we have a mask, but is it new or old format?
LDR R5, [R2, #spMode]
MOVS R5, R5, LSR #27 ;Isolate the 'tell-tale' bits
BEQ %FT98 ;Skip the next bit if old format
;First of all, 'fix' R3, R4, R5 to be 1bpp width
LDMFD R13, {R3-R5} ; Read but don't pull!
ADD R4, R3, R4
; MOV R3, R3, LSL #0 ; R3 = left-bit of column to delete
; MOV R4, R4, LSL #0 ; R4 = right-bit
SUB R4, R4, #1
LDR R5, [R2, #spLBit] ; Account for left-hand wastage
CMP R3, #0 ; (but only for R3 if it is non-zero)
ADDNE R3, R3, R5
ADD R4, R4, R5
Debug id, "Mask deleting from bit to bit ",R3,R4
98
; First a counter for the rows, and a pointer to the start of the row
LDR R5, [R2, #spWidth] ;load word width of image
LDR R8, [R2,#spRBit]
BL GetMaskspWidth ;Work out width of 1bpp mask in words
MOV R0, R5 ;Put it in r0 for the Bl
LDR R5, [R2, #spHeight] ; Number of rows - 1
ADD R6, R6, R2
BL delete_columns_from_data ; Note this returns change in size in R0
Debug id,"Change in size after mask op is noted as ",R0
;
; Rearrange the pointers
LDR R9, [R2, #spNext]
SUB R9, R9, R0
STR R9, [R2, #spNext]
LDR R9, [R1, #saFree]
SUB R9, R9, R0
STR R9, [R1, #saFree]
;
; Delete the columns from the image
99
Pull "R3-R5" ; Unstack 'em this time
ADD R4, R3, R4
MOV R3, R3, LSL R5 ; R3 = left-bit of column to delete
MOV R4, R4, LSL R5 ; R4 = right-bit
SUB R4, R4, #1
LDR R5, [R2, #spLBit] ; Account for left-hand wastage
CMP R3, #0 ; (but only for R3 if it is non-zero)
ADDNE R3, R3, R5
ADD R4, R4, R5
Debug id, "Image deleting from bit to bit ",R3,R4
; First a counter for the rows, and a pointer to the start of the row
LDR R0, [R2, #spWidth] ;load word width of image
LDR R5, [R2, #spHeight] ; Number of rows - 1
LDR R6, [R2, #spImage] ; Source for deletion
ADD R6, R6, R2
LDR R8, [R2,#spRBit]
BL delete_columns_from_data ; Note this returns change in size in R0
Debug id,"Change in size after image op is noted as ",R0
;
; Rearrange the pointers
LDR R8, [R2, #spImage]
LDR R9, [R2, #spTrans]
CMP R8, R9
SUBNE R9, R9, R0
STRNE R9, [R2, #spTrans]
LDR R9, [R2, #spNext]
SUB R9, R9, R0
STR R9, [R2, #spNext]
LDR R9, [R1, #saFree]
SUB R9, R9, R0
STR R9, [R1, #saFree]
;
; Completed the image/mask.
; Now adjust number of columns/width in words/LBit/RBit etc.
LDR R7, [R2, #spWidth] ; R7 = width in bits - 32
MOV R7, R7, LSL #5
LDR R5, [R2, #spLBit] ; R5 = First bit column used
LDR R6, [R2, #spRBit] ; R6 = Number of bit columns used - 1
ADD R6, R6, R7
ADD R7, R7, #32 ; R7 = width in bits
Debug id, "Width (bits), LBit, columns used:",R7,R5,R6
CMP R3, #0 ; Change LBit if deleted first column
STREQ R3, [R2, #spLBit]
Debug id, "Last bit column before deletion, after LH wastage (perhaps):",R6
SUB R8, R4, R3 ; R8 = number of bit columns deleted
ADD R8, R8, #1
SUB R6, R6, R8 ; R6 = last bit column used after columns deleted
Debug id, "Last bit column after deletion:",R6
AND R8, R6, #31 ; R8 = RBit
STR R8, [R2, #spRBit]
MOV R6, R6, LSR #5 ; R6 = number of words used - 1
STR R6, [R2, #spWidth]
Debug id, "RBit and Words-1:",R8,R6
;
; Exit
CLRV
Pull "R1-R11,PC"
; ----------------------------------------------------------
insert_many_columns
;
; Check that the call is trying to start inserting at a column inside the sprite
CMP R3, #0
BLT input_out_of_range
;
; Get log2bpp for the sprite
Push "R1-R2"
LDR R0, [R2, #spMode]
MOV R1, #VduExt_Log2BPP
SWI XOS_ReadModeVariable
Debug id,"Read mode variable log2bpp for mode:",R2,R0
SETV CS
MOVVC R5, R2
Pull "R1-R2"
Pull "R1-R11,PC",VS
;
; Make R3 = left bit to start inserting at, R4 = number of bits to insert
MOV R3, R3, LSL R5 ; R3 = left-bit of column to delete
LDR R6, [R2, #spLBit] ; Account for left-hand wastage
ADD R3, R3, R6
MOV R4, R4, LSL R5 ; R4 = number of bits
;
; Get change in width in words of the new sprite versus the old sprite
LDR R5, [R2, #spRBit] ; Check the bit to insert at is inside the sprite
LDR R6, [R2, #spWidth]
ADD R6, R5, R6, LSL #5 ; R6 = current right-most bit column + 1
ADD R6, R6, #1
Debug id,"Insert at bit, Last bit=",r3,r6
CMP R3, R6 ; If this is before the insertion point then trying
BGT input_out_of_range ; to insert off the end of the sprite
ADD R5, R4, R5 ; Work out the right-most bit after insertion
MOV R5, R5, LSR #5 ; Find out if it intrudes on a new word or not
LDR R6, [R2, #spHeight] ; Find total number of words extra required for image
ADD R6, R6, #1
MUL R5, R6, R5
LDR R6, [R2, #spImage] ; More room is required if there is also a mask
LDR R0, [R2, #spTrans]
MOV R7, R5 ; No mask, so only 1 times the extra space is needed
CMP R6, R0
BEQ skip_past ; No mask, so skip the next, mask-only, bit.
;There is a mask, so more memory needs to be allocated...
LDR R8, [R2, #spMode] ;
MOVS R8, R8, LSR #27 ; Ah, but is it a new or old format sprite?
MOVEQ R7, R5, LSL #1 ; Old format, so 2 times the extra space is needed,
DebugIf EQ,ag,"Old format mask, so R7,R5 are",R7,R5
BEQ skip_past ; and we can skip the new format gumph
Push "R5-R6,R8" ; Well, it must be new format then!
Debug ag,"New format mask."
LDR R5, [R2, #spWidth]
BL GetMaskspWidth ; Returns R5=width of 1bpp mask, with R8=new spRBit
Push "R1-R2"
LDR R0, [R2, #spMode]
MOV R1, #VduExt_Log2BPP
SWI XOS_ReadModeVariable
Debug id,"Read mode variable log2bpp for mode:",R2,R0
ADD R5, R8, R4, LSR R2 ; R5 = rightmost bit after insertion
Pull "R1-R2"
MOV R5, R5, LSR #5 ; Convert it back to words
LDR R6, [R2, #spHeight]
ADD R6, R6, #1
MUL R5, R6, R5 ; R5 = total extra memory required due to mask insertions
Debug ag,"Extra space required for mask (words)=",R5
ADD R7, R7, R5 ; Add this onto the memory required for the sprite insertions
Debug ag,"Total space required (words)=",R7
Pull "R5-R6,R8"
;
; Check there is enough spare room for the extra columns
skip_past
Debug ag,"Here, R7 = total space required (words) =",R7
Debug ag," R5 = sprite space requird (words) =",R5
MOV R0, R7 ; Don't take our R7 value away!
LDR R8, [R1, #saFree] ; Get last byte required
ADD R7, R8, R7, LSL #2
LDR R8, [R1, #saEnd] ; Check it is inside the sprite area
Debug id,"NewFree,End=",r7,r8
CMP R7, R8
BGT no_room_to_insert ; If it isn't then give an error
MOV R7, R0 ; Grab our R7 value back
;
; Start insertion stage by moving the mask and rest of sprites above expanded image
Debug id, "Inserting n bits starting at:",R4,R3
Debug id, "Requires extra memory of words:",R5
MOV R0, R5, LSL#2 ; Bytes to move memory up by (ie amount to be inserted in image)
LDR R9, [R2, #spTrans] ; Memory to move up (start)
CMP R9, R6 ; If no mask then insert before next sprite
LDREQ R9, [R2, #spNext]
ADD R9, R9, R2
LDR R10, [R1, #saFree] ; Memory to move up (end)
ADD R10, R10, R1
BL move_memory_up
Debug ag,"Moved memory up above image insertion point."
;
; Now insert columns into the image
Push "R1,R5"
LDR R5, [R2, #spHeight]
LDR R1, [R2, #spWidth] ; Required for the insert_columns routine
Debug ag,"Inserting columns in data. Height (lines), width (words) =",R5,R1
BL insert_columns_in_data ; Insert R4 bit columns in image R6 at column R3. No rows-1 = R5
Debug ag,"Inserted columns in image."
Pull "R1,R5"
;
; Adjust the pointers
MOV R9, R7 ; Again, keep our R7 safe
LDR R7, [R2, #spNext] ; Adjust offset to next sprite
ADD R7, R7, R0
STR R7, [R2, #spNext]
LDR R7, [R1, #saFree] ; Adjust offset to free block of sprite area
ADD R7, R7, R0
STR R7, [R1, #saFree]
LDR R7, [R2, #spTrans] ; If no mask then don't adjust the mask pointer
Push R4
CMP R6, R7
BEQ %FT99 ; Skip the next bit if no mask!
ADD R6, R7, R0
STR R6, [R2, #spTrans]
MOV R7, R9 ; Again, grab our R7 back
;
; Move other sprites up beyond expanded mask
Debug ag,"Well, we'd better do the mask now..."
Debug ag,"R7 and R5 are",R7,R5
SUB R0, R7, R5 ; R0 is the amount to move the mask by (total-sprite)
MOV R0, R0, LSL #2 ; Words to bytes conversion
Debug ag,"So, amount (bytes) to move mask up by is",R0
LDR R9, [R2, #spNext] ; Memory to move up (start)
ADD R9, R9, R2
LDR R10, [R1, #saFree] ; Memory to move up (end)
ADD R10, R10, R1
BL move_memory_up
Debug ag,"Moved memory up above mask insertion point."
;
; Insert columns into the mask
LDR R7, [R2, #spRBit] ; Keep spRBit safe!
Push "R1, R7-R8"
LDR R5, [R2, #spMode]
MOVS R5, R5, LSR #27 ; New or old format sprite?
LDREQ R1, [R2, #spWidth] ; Old format
DebugIf EQ,ag,"Old format sprite"
BEQ next_bit ; Skip the next chunk if sprite is old format
Debug ag,"New format sprite"
Push "R0,R2"
LDR R0, [R2, #spMode]
MOV R1, #VduExt_Log2BPP
SWI XOS_ReadModeVariable
Debug id,"Read mode variable log2bpp for mode:",R2,R0
MOV R4, R4, LSR R2 ; R4 converted to 1 bpp
MOV R3, R3, LSR R2
Pull "R0,R2"
LDR R5, [R2, #spWidth]
BL GetMaskspWidth
Debug ag,"spWidth of mask is",R5
Debug ag,"spRBit of mask is",R8
MOV R1, R5 ; Needed for insert_columns routine
STR R8, [R2, #spRBit]
next_bit
LDR R5, [R2, #spHeight]
Debug ag,"just before inserting columns, spWidth of mask is",R1
Debug ag,"just before inserting columns, spRBit of mask is",R8
BL insert_columns_in_data ; Insert R4 bit columns in mask R6 at column R3. No rows-1 = R5
Debug ag,"Inserted columns in mask."
Pull "R1, R7-R8"
STR R7, [R2, #spRBit]
;
; Adjust the pointers
LDR R7, [R2, #spNext] ; Adjust offset to next sprite
ADD R7, R7, R0
STR R7, [R2, #spNext]
LDR R7, [R1, #saFree] ; Adjust offset to free block of sprite area
ADD R7, R7, R0
STR R7, [R1, #saFree]
;
; Exit
99
;
; Change data in the sprite block
Pull R4
LDR R9, [R2, #spRBit] ; Work out right-most bit after insertion
ADD R9, R4, R9
LDR R10, [R2, #spWidth] ; R10 = words used -1
ADD R10, R10, R9, LSR #5
STR R10, [R2, #spWidth]
AND R9, R9, #31 ; R9 = last bit used
STR R9, [R2, #spRBit]
CLRV
Pull "R1-R11,PC"
; ----------------------------------------------------------
; Move the memory from [R9+R0 to R10] down to [R9 to R10-R0]
move_memory_down
Push "R1,R3,R9,R14"
ADD R1, R9, R0
Debug id,"Moving memory down from,to,finish:",R1,R9,R10
01
CMP R1, R10
BGE %FT02
LDR R3, [R1], #4
STR R3, [R9], #4
B %BT01
02
Debug id,"Moved memory down. From,to,finish are now:",R1,R9,R10
Pull "R1,R3,R9,PC"
; --------------------------------------------------------
; Move the memory from [R9 to R10] up to [R9+R0 to R10+R0]
move_memory_up
Push "R1,R3,R4,R9,R14"
ADD R1, R10, R0
Debug id,"Moving memory up from,to,finish:",R10,R1,R9
CMP r9, r10
01
LDRCC R3, [R10, #-4]!
STRCC R3, [R1, #-4]!
CMP r9, r10
BCC %BT01
MOV lr, #0
CMP r9, r1
02
STRCC lr, [r1, #-4]!
CMP r9, r1
BCC %BT02
Debug id,"Moved memory up. From,to,finish are now:",R10,R1,R9
Pull "R1,R3,R4,R9,PC"
; --------------------------------------------------------
; Delete columns from an image/mask
delete_columns_from_data
; R0 = Width of image/mask on entry, change in size on exit
; R5 = Number of rows in mask
; R6 = Source for deletion
; R8 = spRBit
Push "R1-R11,R14"
Push R0 ;push it separately
Push R8 ;this separate too
MOV R7, R6 ; Destination for deletion = source
Debug id,"Start of line with R0, start, end, source, dest, R8:",R0,R3,R4,R6,R7,R8
;
; Now for all the rows...
01
;
; Counter to see how many bits have been copied
MOV R10, #0
;
; Transfer source to destination until at first word in the row to worry about
SUBS R9, R3, #32
02
BMI %FT99
LDR R8, [R6], #4 ; Copy whole word from source to destination
STR R8, [R7], #4
ADD R10, R10, #32 ; Increase 'bits copied' by 1 word = 32 bits
SUBS R9, R9, #32 ; Decrement counter by 1 word = 32 bits
B %BT02 ; Loop until all the whole words have been done
;
; Now load the source word at the word including the first column to delete
99
LDR R8, [R6] ; R8 = word including first column to delete
RSB R9, R9, #0 ; R9 = number of unwanted bits in R8
MOV R8, R8, LSL R9 ; Clear the unwanted bits
MOV R8, R8, LSR R9
;
; Skip forward along the source until at the last column to delete
SUB R10, R4, R10 ; R10 = bits left before last bit to copy in row
02
CMP R10, #32 ; If less than 32 then already at the right place
BLT %FT99
ADD R6, R6, #4 ; Else move on the source pointer
SUB R10, R10, #32 ; and remove 1 word from the bits left counter
B %BT02
;
; Now at the word which includes the last column to delete. Bit twiddling from now on
99
;
; R8 = combination of word including first column to delete and last column to delete
;
LDR R11, [R6], #4
MOV R11, R11, LSR R10 ; Remove unwanted bits from the front
MOV R11, R11, LSR #1
RSB R9, R9, #32 ; Shift it up past the 32-R9 bits correct in R8
ORR R8, R8, R11, LSL R9
;
; If new R9=bottom 5 bits of R3 is bigger than R4 then we need to store this word and move on
Debug id,"Middle with R9,R10,R6,R7",R9,R10,R6,R7
CMP R9, R10 ; Did the last shift shift bits out of the top of R8?
STRGT R8, [R7],#4 ; If so then store the word
RSBGT R9, R9, #32 ; Get bits shifted out into bottom of R8
MOVGT R8, R11, LSR R9
ADDGT R9, R9, R10 ; R9 = number of valid bits in R8
RSBGT R9, R9, #31
ADDLE R9, R9, #31 ; Else R9 = number of valid bits in R8
SUBLE R9, R9, R10
;
; Now we have considered all the words from the start of the row to the one including the last deleted column
MOV R10, R4, LSR #5 ; R10 = number of source words examined - 1
LDR R0, [R13, #4] ; Read R0 directly off the stack
Debug id,"R0 read off stack as ",R0
MOV R11, R0 ; R11 = number of source words in a row - 1
02
CMP R10, R11 ; While source words examined < source words in a row
BGE %FT99
LDR R0, [R6], #4 ; R0 = next source word
ORR R8, R8, R0, LSL R9 ; Add in bottom bits above the R9 valid bits
STR R8, [R7], #4 ; Store R8 in destination
RSB R9, R9, #32 ; New R8 = top R9 bits of R0
MOV R8, R0, LSR R9
RSB R9, R9, #32
ADD R10, R10, #1 ; Source words examined ++
B %BT02 ; End while
;
; Finished loop. Any valid bits left over?
99
LDR R10, [R13] ; read R8 off the stack into R10
Debug id,"Read R8 off stack into R10 as",R10
RSB R10, R10, #31
CMP R9, R10
STRGT R8, [R7], #4
Debug id,"End of line with line, valid bits, data, source, dest:",R5,R9,R8,R6,R7
;
; Loop for all the rows in the sprite image/mask
SUBS R5, R5, #1
BPL %BT01
;
; Finished all the deletion. Note it must still shuffle down the memory from the end of
; the old image/mask to the end of the new image/mask
Pull R8
Pull R0 ;Need to do this to restore stack
SUB R0, R6, R7
MOV R9, R7
LDR R10, [R1, #saFree]
ADD R10, R10, R1
BL move_memory_down
;
; Return R0 = change in size of data
Pull "R1-R11,PC"
; --------------------------------------------------------
; Insert columns from an image/mask
insert_columns_in_data
; R1 = spWidth
; R5 = Number of rows in mask/image - 1
; R6 = Offset from R2 of source for insertion
; R3 = bit column to insert before
; R4 = number of columns to insert
; R0 = change in length of image/mask in bytes after insertion
Push "R0-R12,R14"
Debug id,"Entry:R0,R3,R4,R5,R6",R0,R3,R4,R5,R6
;
; Get R6 = source pointer to just after the end of the last row
ADD R9, R5, #1
MOV R10, R1
ADD R10, R10, #1
MOV R10, R10, LSL #2 ;R10 = spWidth in bytes
MLA R6, R10, R9, R6
;
; Get R7 = destination pointer to just after the end of the finished sprite
ADD R6, R6, R2
ADD R7, R6, R0
Debug id,"Start of line with start,number, source, dest:",R3,R4,R6,R7
;
; Make R3 be the bit column in the destination just after the end of the inserted columns
ADD R3, R3, R4
;
; Now for all the rows...
02
;
; R10 = Bit number of start of destination word pointed at [R7-4]. R11 = 32- (new RBit after insertion + 1) = waste bits in word
MOV R10, R1
LDR R11, [R2, #spRBit]
ADD R10, R11, R10, LSL #5
ADD R10, R10, R4
AND R11, R10, #31
ADD R11, R11, #1
RSB R11, R11, #32
BIC R10, R10, #31
;
; R9 = number of bits in R8 which will be valid
LDR R9, [R2, #spRBit]
ADD R9, R9, #1
;
; Get the source word on the current line into R8 Its bottom R9 bits are needed/valid.
Debug id,"Entry to first loop.source,dest,flag,r9,r10,r11:",R6,R7,R12,R9,R10,R11
01
; Registers have the following meaning at this point:
; r3 = 1st bit column after inserted section
; r4 = width of inserted section
; r6 = source word + 4
; r7 = destination word + 4
; r9 = number of LSBits at r6 unused as yet (1 to 32)
; r10 = 1st column of destination word
; r11 = amount of MSBits to zero out of destination word
LDR R8, [R6, #-4]!
;
; Make R8 have its top R9 bits valid, all other bits 0
RSB R9, R9, #32 ; R9 = 32 - x
MOV R8, R8, LSL R9 ; Shifts bits [0,x-1] up to [32-x,32-x+x-1]=[32-x,31]
RSB R9, R9, #32 ; Restore R9
;
; Read in the bits from the word before it, to make all of R8 valid (ignores LH wastage)
LDR R14, [R6, #-4]
ORR R8, R8, R14, LSR R9
;
; R8 now contains the last 32 bits of pixel bit data from the row of the sprite
; Shift it right to allow for RH wastage in destination sprite
MOV R8, R8, LSR R11
;
; If we have shifted out some of this word then move source
; pointer forward again to reread this word next time
ADD R9, R9, R11
CMP R9, #32
ADDGT R6, R6, #4 ; Have shifted R14-32 bits out. Hence move source pointer back
SUBGT R9, R9, #32 ; so we reread it next time.
;
; Loop until we have got a word which has some bits of inserted columns in it
CMP R3, R10
STRLE R8, [R7, #-4]!
SUBLE R10, R10, #32
MOVLE R11, #0
BLE %BT01
Debug id,"First loop complete.source,dest,flag,r10,R3,R9:",R6,R7,R12,R10,R3,R9
; Registers have the following meaning at this point:
; r3 = 1st bit column after inserted section
; r4 = width of inserted section
; r6 = source word
; r7 = destination word
; r8 = 32 source bits extracted and ready to use from previous step aligned for destination
; r9 = number of LSBits at r6 unused as yet (1 to 32)
; r10 = 1st column of destination word
; Mask off bottom (r3 AND 31) bits for hole
ANDS r14, r3, #31
MOVEQ r14, #32
MOV r8, r8, LSR r14
MOV r8, r8, LSL r14
; Move back a word if all of this word has been masked off
ADD r9, r9, r14
CMP r9, #32
ADDGT r6, r6, #4
; Remove the bits which have been blanked from the number of bits to insert
SUB r14, r4, r14
ADD r14, r14, #32
B %FT03
01
STR R8, [R7, #-4]! ; Store another word
MOV R8, #0
SUB R10, R10, #32
03
SUBS R14, R14, #32 ; Decrease counter of bits inserted
BGT %BT01
SUB r14, r3, r4 ; start column of insertion
ANDS r14, r14, #31 ; distance into source word
; If extracts at least a bit from source word then do so
RSBNE r14, r14, #32
LDRNE r11, [r6, #-4]!
MOVNE r11, r11, LSL r14
ORRNE r8, r8, r11, LSR r14
; Store it away
STR r8, [r7, #-4]!
SUBS r10, r10, #32
; Keep copying words of data until we have finished the row
01
BLT %FT99
LDR R8, [R6, #-4]!
STR R8, [R7,#-4]!
SUBS R10, R10, #32
B %BT01
;
; Finished a row, so loop for all rows
99
Debug id,"Finished Row with source,dest:",R5,R6,R7
SUBS R5, R5, #1
BPL %BT02
;
; Finished all the rows. Exit time.
Debug id,"Finished the rows with source,dest:",R6,R7
Pull "R0-R12,PC"
; *****************************************************************************
;
; GetMaskspWidth - convert spWidth for data to spWidth for mask (1bpp masks)
;
; NOTE: This routine should be identical to the same routine in VduGrafH except it does
; not return the updated PSR
;
; Internal routine.
;
; in: R5 = spWidth (ie width in words-1)
; (expects R2->sprite)
;
; out: R5 = spWidth (words -1) for mask data
; R8 = Last bit (spRBit) used in mask data
; should only be called for new format sprites, but will cope with old too
GetMaskspWidth ROUT
Push "R0, LR"
Debug ag,"Entered GetMaskspWidth with R5,R8",R5,R8
LDR LR, [R2, #spMode] ; fetch the sprite mode
MOVS LR, LR, LSR #27 ; isolate the sprite type and test for =0
Pull "R0, PC",EQ ; if an old format sprite, return R5 unchanged
; treat any T>max sprites as 32bpp
CMP LR, #SpriteType_MAX
MOVCS LR, #SpriteType_Substitute
; bugfix 9/8/93: get log2bpp this way
ADRL R0, NSM_bpptable
LDRB LR, [R0, LR] ; get the log2bpp to LR
RSB LR, LR, #5 ; and change to 5-log2bpp
MOV R5, R5, LSL LR ; number of pixels for full words
RSB LR, LR, #5 ; now switch back to log2bpp
LDR R0, [R2, #spRBit]
ADD R0, R0, #1
ADD R5, R5, R0, LSR LR
ANDS LR, R5, #&1F ; fit exactly in a number of words ?
SUB R8, LR, #1 ; alter the last bit used for the mask data
; fix bug MED-01130....
AND R8, R8, #&1F ; ....bring back into range 00-1F (may be -1 here)
MOVNE LR, #1 ; if not, add an extra word
ADD R5, LR, R5, LSR #5 ; add the whole number of words
SUB R5, R5, #1 ; returns as words-1
Debug ag,"Left GetMaskspWidth with R5,R8",R5,R8
Pull "R0, PC"
NSM_bpptable
; note, yes - I know this could be type-1, but at some point some new type
; will break the relationship so it's a table from day 1 to cope with this
DCB 99, 0, 1, 2, 3, 4, 5
; T= 0 1 2 3 4 5 6
; cols= old, 2, 4, 16, 256, 32k, 16M
ALIGN
END