mirror of
https://github.com/lscharen/iigs-game-engine.git
synced 2024-11-26 07:49:17 +00:00
Nearly complete integration of sprites into rendering function
This commit is contained in:
parent
8f0e82cb04
commit
631f40da23
@ -129,6 +129,25 @@ asr8 mac
|
||||
ror
|
||||
<<<
|
||||
|
||||
; Inline macros for fast calculation of some internal values
|
||||
_TileStoreOffset mac
|
||||
lda ]2
|
||||
asl
|
||||
tay
|
||||
lda ]1
|
||||
asl ; Assume in range, so asl puts a 0 bit into the carry
|
||||
adc TileStoreYTable,y
|
||||
<<<
|
||||
|
||||
_; Macro variant to calculate inline from any source
|
||||
_SpriteVBuffAddr mac
|
||||
lda ]2
|
||||
clc
|
||||
adc #NUM_BUFF_LINES
|
||||
xba
|
||||
adc ]1
|
||||
<<<
|
||||
|
||||
; Macro to define script steps
|
||||
ScriptStep MAC
|
||||
IF #=]5
|
||||
|
12
src/Core.s
12
src/Core.s
@ -8,7 +8,7 @@
|
||||
use .\Defs.s
|
||||
|
||||
; Feature flags
|
||||
NO_INTERRUPTS equ 0 ; turn off for crossrunner debugging
|
||||
NO_INTERRUPTS equ 1 ; turn off for crossrunner debugging
|
||||
NO_MUSIC equ 1 ; turn music + tool loading off
|
||||
|
||||
; External data provided by the main program segment
|
||||
@ -342,7 +342,7 @@ ClearKbdStrobe sep #$20
|
||||
rep #$20
|
||||
rts
|
||||
|
||||
; Read the keyboard and paddle controls and return in a game-cotroller-like format
|
||||
; Read the keyboard and paddle controls and return in a game-controller-like format
|
||||
ReadControl ENT
|
||||
pea $0000 ; low byte = key code, high byte = %------AB
|
||||
|
||||
@ -352,8 +352,8 @@ ReadControl ENT
|
||||
beq :BNotDown
|
||||
|
||||
lda #1
|
||||
ora 1,s
|
||||
sta 1,s
|
||||
ora 2,s
|
||||
sta 2,s
|
||||
|
||||
:BNotDown
|
||||
ldal COMMAND_KEY_REG
|
||||
@ -361,8 +361,8 @@ ReadControl ENT
|
||||
beq :ANotDown
|
||||
|
||||
lda #2
|
||||
ora 1,s
|
||||
sta 1,s
|
||||
ora 2,s
|
||||
sta 2,s
|
||||
|
||||
:ANotDown
|
||||
ldal KBD_STROBE_REG ; read the keyboard
|
||||
|
@ -78,8 +78,8 @@ _Render
|
||||
jsr _ApplyBG0XPosPre
|
||||
jsr _ApplyBG1XPosPre
|
||||
|
||||
; jsr _RenderSprites ; Once the BG0 X and Y positions are committed, update sprite data
|
||||
; nop
|
||||
jsr _RenderSprites ; Once the BG0 X and Y positions are committed, update sprite data
|
||||
|
||||
jsr _UpdateBG0TileMap ; and the tile maps. These subroutines build up a list of tiles
|
||||
jsr _UpdateBG1TileMap ; that need to be updated in the code field
|
||||
|
||||
|
432
src/Sprite.s
432
src/Sprite.s
@ -28,13 +28,37 @@ InitSprites
|
||||
|
||||
; This function looks at the sprite list and renders the sprite plane data into the appropriate
|
||||
; tiles in the code field
|
||||
forceSpriteFlag ds 2
|
||||
_RenderSprites
|
||||
|
||||
; First step is to look at the StartX and StartY values. If the offsets have changed from the
|
||||
; last time that the frame was rederer, then we need to mark all of the sprites as dirty so that
|
||||
; the tiles that they were located at on the previous frame will be refreshed
|
||||
|
||||
stz forceSpriteFlag
|
||||
lda StartX
|
||||
cmp OldStartX
|
||||
beq :no_chng_x
|
||||
lda #SPRITE_STATUS_DIRTY
|
||||
sta forceSpriteFlag
|
||||
:no_chng_x
|
||||
lda StartY
|
||||
cmp OldStartY
|
||||
beq :no_chng_y
|
||||
lda #SPRITE_STATUS_DIRTY
|
||||
sta forceSpriteFlag
|
||||
:no_chng_y
|
||||
|
||||
; Second step is to scan the list of spries. A sprite is either clean or dirty. If it's dirty,
|
||||
; then its position had changed, so we need to add tiles to the dirty queue to make sure the
|
||||
; playfield gets update. If it's clean, we can skip eerything.
|
||||
|
||||
ldx #0
|
||||
:loop lda _Sprites+SPRITE_STATUS,x
|
||||
:loop lda _Sprites+SPRITE_STATUS,x ; If the sttus is zero, that's the sentinel value
|
||||
beq :out
|
||||
; cmp #SPRITE_STATUS_DIRTY
|
||||
; beq :render
|
||||
bra :render
|
||||
ora forceSpriteFlag
|
||||
bit #SPRITE_STATUS_DIRTY ; If the dirty flag is set, do the things....
|
||||
bne :render
|
||||
:next inx
|
||||
inx
|
||||
bra :loop
|
||||
@ -46,194 +70,216 @@ _RenderSprites
|
||||
; from.
|
||||
:render
|
||||
stx tmp0 ; stash the X register
|
||||
txy ; switch to the Y register
|
||||
|
||||
txy
|
||||
ldx _Sprites+OLD_VBUFF_ADDR,y
|
||||
jsr _EraseTileSprite ; erase from the old position
|
||||
; ldx _Sprites+OLD_VBUFF_ADDR,y
|
||||
; jsr _EraseTileSprite ; erase from the old position
|
||||
|
||||
ldx _Sprites+VBUFF_ADDR,y
|
||||
lda _Sprites+TILE_DATA_OFFSET,y
|
||||
; Draw the sprite into the sprint plane buffer(s)
|
||||
|
||||
ldx _Sprites+VBUFF_ADDR,y ; Get the address in the sprite plane to draw at
|
||||
lda _Sprites+TILE_DATA_OFFSET,y ; and the tile address of the tile
|
||||
tay
|
||||
jsr _DrawTileSprite ; draw the sprite into the sprite plane
|
||||
ldx tmp0
|
||||
|
||||
ldy #0 ; flags to mark if the sprite is aligned to the code field grid or not
|
||||
; Mark the appropriate tiles as dirty and as occupied by a sprite so that the ApplyTiles
|
||||
; subroutine will get the drawn data from the sprite plane into the code field where it
|
||||
; can be drawn to the screen
|
||||
|
||||
lda _Sprites+SPRITE_X,x ; Will need some special handling for X < 0
|
||||
sta tmp3
|
||||
ldx tmp0 ; Restore the index into the sprite array
|
||||
jsr _MarkDirtySprite8x8 ; Eventually will have routines for all sprite sizes
|
||||
bra :next
|
||||
|
||||
; Marks a 8x8 square as dirty. The work here is mapping from local screen coordinates to the
|
||||
; tile store indices. The first step is to adjust the sprite coordinates based on the current
|
||||
; code field offsets and then cache variations of this value needed in the rest of the subroutine
|
||||
;
|
||||
; The SpritX is always the MAXIMUM value of the corner coordinates. We subtract (SpriteX + StartX) mod 4
|
||||
; to find the coordinate in the sprite plane that match up with the tile in the play field and
|
||||
; then use that to calculate the VBUFF address to copy sprite data from.
|
||||
;
|
||||
; StartX SpriteX z = * mod 4 (SprietX - z)
|
||||
; ----------------------------------------------
|
||||
; 0 8 0 8
|
||||
; 1 8 1 7
|
||||
; 2 8 2 6
|
||||
; 3 8 3 5
|
||||
; 4 9 1 8
|
||||
; 5 9 2 7
|
||||
; 6 9 3 6
|
||||
; 7 9 0 9
|
||||
; 8 10 2 8
|
||||
; ...
|
||||
;
|
||||
; For the Y-coordinate, we just use "mod 8" instead of "mod 4"
|
||||
|
||||
_MarkDirtySprite8x8
|
||||
|
||||
; First, bounds check the X and Y coodinates of the sprite and, if they pass, pre-calculate some
|
||||
; values that we can use later
|
||||
|
||||
lda _Sprites+SPRITE_Y,x ; This is a signed value
|
||||
bpl :y_is_pos
|
||||
cmp #$FFF9 ; If a tile is <= -8 do nothing, it's off-screen
|
||||
bcs :y_is_ok
|
||||
rts
|
||||
:y_is_pos cmp ScreenHeight ; Is a tile is > ScreenHeight, it's off-screen
|
||||
bcc :y_is_ok
|
||||
rts
|
||||
:y_is_ok
|
||||
|
||||
; The sprite's Y coordinate is in a range that it will impact the visible tiles that make up the play
|
||||
; field. Figure out what tile(s) they are and what part fo the sprite plane data/mask need to be
|
||||
; accessed to overlay with the tile pixels
|
||||
|
||||
clc
|
||||
adc StartYMod208 ; Adjust for the scroll offset (could be a negative number!)
|
||||
tay ; Save this value
|
||||
and #$0007 ; Get (StartY + SpriteY) mod 8. For negative, this is ok because 65536 mod 8 = 0.
|
||||
sta tmp6
|
||||
|
||||
eor #$FFFF
|
||||
inc
|
||||
clc
|
||||
adc _Sprites+SPRITE_Y,x ; subtract from the SpriteY position
|
||||
sta tmp1 ; This position will line up with the tile that the sprite overlaps with
|
||||
|
||||
tya ; Get back the position of the sprite in the code field
|
||||
bpl :ty_is_pos
|
||||
clc
|
||||
adc #208 ; wrap around if we are slightly off-screen
|
||||
bra :ty_is_ok
|
||||
:ty_is_pos cmp #208 ; check if we went too far positive
|
||||
bcc :ty_is_ok
|
||||
sbc #208
|
||||
:ty_is_ok
|
||||
lsr
|
||||
lsr
|
||||
lsr ; This is the row in the Tile Store for top-left corner of the sprite
|
||||
sta tmp2
|
||||
|
||||
; Same code, except for the X coordiante
|
||||
|
||||
lda _Sprites+SPRITE_X,x
|
||||
bpl :x_is_pos
|
||||
cmp #$FFFD ; If a tile is <= -4 do nothing, it's off-screen
|
||||
bcs :x_is_ok
|
||||
rts
|
||||
:x_is_pos cmp ScreenWidth ; Is a tile is > ScreeWidth, it's off-screen
|
||||
bcc :x_is_ok
|
||||
rts
|
||||
:x_is_ok
|
||||
clc
|
||||
adc StartXMod164
|
||||
tay
|
||||
and #$0003
|
||||
sta tmp5 ; save the mod value to test for alignment later
|
||||
|
||||
bit #$0003 ; If the botton bit are zero, then we're aligned
|
||||
beq :aligned_x
|
||||
ldy #4
|
||||
:aligned_x
|
||||
eor #$FFFF
|
||||
inc
|
||||
clc
|
||||
adc _Sprites+SPRITE_X,x
|
||||
sta tmp3
|
||||
|
||||
cmp #164
|
||||
bcc *+5
|
||||
tya
|
||||
bpl :tx_is_pos
|
||||
clc
|
||||
adc #164
|
||||
bra :tx_is_ok
|
||||
:tx_is_pos cmp #164
|
||||
bcc :tx_is_ok
|
||||
sbc #164
|
||||
:tx_is_ok
|
||||
lsr
|
||||
lsr
|
||||
pha ; Save the tile column
|
||||
|
||||
lda _Sprites+SPRITE_Y,x
|
||||
sta tmp2
|
||||
|
||||
clc
|
||||
adc StartYMod208
|
||||
|
||||
bit #$0007
|
||||
beq :aligned_y
|
||||
iny
|
||||
iny
|
||||
:aligned_y
|
||||
|
||||
cmp #208
|
||||
bcc *+5
|
||||
sbc #208
|
||||
lsr
|
||||
lsr
|
||||
lsr
|
||||
|
||||
tyx ; stash the alignment in the x register for dispatch
|
||||
jmp (:mark_dirty,x)
|
||||
; :mark_dirty dw :corner,:column,:row,:square
|
||||
:mark_dirty dw :corner,:corner,:corner,:corner
|
||||
|
||||
; Just mark the square with the sprite as dirty
|
||||
:corner tay
|
||||
plx
|
||||
jsr _MarkAsDirty
|
||||
ldx tmp0
|
||||
brl :next
|
||||
|
||||
; Mark the left column (x, y) and (x, y+1) as dirty
|
||||
:column tay
|
||||
plx
|
||||
jsr _MarkAsDirty
|
||||
|
||||
iny
|
||||
cpy #26
|
||||
bcc *+5
|
||||
ldy #0
|
||||
lda tmp2
|
||||
clc
|
||||
adc #8
|
||||
sta tmp2
|
||||
|
||||
jsr _MarkAsDirty
|
||||
ldx tmp0
|
||||
brl :next
|
||||
|
||||
; Mark the top row (x, y) and (x+1, y) as dirty
|
||||
:row tay
|
||||
plx
|
||||
jsr _MarkAsDirty
|
||||
|
||||
inx
|
||||
cpx #41
|
||||
bcc *+5
|
||||
ldx #0
|
||||
lda tmp3
|
||||
clc
|
||||
adc #4
|
||||
sta tmp3
|
||||
|
||||
|
||||
jsr _MarkAsDirty
|
||||
ldx tmp0
|
||||
brl :next
|
||||
|
||||
; Mark all four squares as dirty
|
||||
:square tay
|
||||
lda 1,s
|
||||
tax
|
||||
jsr _MarkAsDirty
|
||||
|
||||
inx
|
||||
cpx #41
|
||||
bcc *+5
|
||||
ldx #0
|
||||
lda tmp3
|
||||
clc
|
||||
adc #4
|
||||
sta tmp3
|
||||
|
||||
jsr _MarkAsDirty
|
||||
|
||||
iny
|
||||
cpy #26
|
||||
bcc *+5
|
||||
ldy #0
|
||||
lda tmp2
|
||||
clc
|
||||
adc #8
|
||||
sta tmp2
|
||||
|
||||
jsr _MarkAsDirty
|
||||
|
||||
plx
|
||||
lda tmp3
|
||||
sec
|
||||
sbc #4
|
||||
sta tmp3
|
||||
|
||||
jsr _MarkAsDirty
|
||||
ldx tmp0
|
||||
brl :next
|
||||
|
||||
_MarkAsDirty
|
||||
phx
|
||||
phy
|
||||
|
||||
jsr _GetTileStoreOffset ; Get the tile store value
|
||||
jsr _PushDirtyTile ; Enqueue for processing (Returns offset in Y-register)
|
||||
|
||||
lda TileStore+TS_SPRITE_FLAG,y ; If this tile has already been flagged on this frame, avoid recalculating the address
|
||||
beq :early_out
|
||||
|
||||
lda #TILE_SPRITE_BIT ; Mark this tile as having a sprite, regardless of whether it was already enqueued
|
||||
sta TileStore+TS_SPRITE_FLAG,y
|
||||
|
||||
jsr _SetSpriteAddr
|
||||
|
||||
:early_out
|
||||
ply
|
||||
plx
|
||||
rts
|
||||
|
||||
; Set the TileStore+TS_SPRITE_ADDR for tile that a sprite is on.
|
||||
;
|
||||
; To calculate the sprite plane coordinate for this tile column. We really just have to compensate
|
||||
; for the StartXMod164 mod 4 value, so the final value is (SPRITE_X + (StartXMod164 mod 4)) & 0xFFFC
|
||||
; for the horizontal and (SPRITE_Y + (StartYMod208 mod 8)) & 0xFFF8
|
||||
;
|
||||
; The final address is (Y + NUM_BUFF_LINES) * 256 + X
|
||||
;
|
||||
; tmp2 = sprite Y coordinate
|
||||
; tmp3 = sprite X coordinate
|
||||
; Y = tile record index
|
||||
_SetSpriteAddr
|
||||
lda StartYMod208
|
||||
and #$0007
|
||||
clc
|
||||
adc tmp2
|
||||
and #$00F8
|
||||
clc
|
||||
adc #NUM_BUFF_LINES
|
||||
xba
|
||||
sta tmp4
|
||||
|
||||
lda StartXMod164
|
||||
and #$0003
|
||||
clc
|
||||
adc tmp3
|
||||
and #$00FC
|
||||
clc
|
||||
adc tmp4
|
||||
sta TileStore+TS_SPRITE_ADDR,y
|
||||
; At this point we have the top-left corner in the sprite plane (tmp1, tmp3) and the corresponding
|
||||
; column and row in the tile store (tmp2, tmp4). The next step is to add these tile locations to
|
||||
; the dirty queue and set the sprite flag along with the VBUFF location. We try to incrementally
|
||||
; calculate new values to avoid re-doing work.
|
||||
|
||||
_SpriteVBuffAddr tmp3;tmp1
|
||||
pha
|
||||
_TileStoreOffset tmp4;tmp2
|
||||
tax
|
||||
lda #TILE_SPRITE_BIT
|
||||
sta TileStore+TS_SPRITE_FLAG,x
|
||||
pla
|
||||
sta TileStore+TS_SPRITE_ADDR,x
|
||||
txa
|
||||
jsr _PushDirtyTile
|
||||
|
||||
; Now see if we need to extend to other tiles. If the mod values are not equal to zero, then
|
||||
; the width of the sprite will extend into the adjacent code field tiles.
|
||||
|
||||
lda tmp5
|
||||
beq :no_x_oflow
|
||||
|
||||
lda tmp3
|
||||
clc
|
||||
adc #4
|
||||
sta tmp7
|
||||
lda tmp4
|
||||
inc
|
||||
cmp #41
|
||||
bcc *+5
|
||||
lda #0
|
||||
sta tmp8
|
||||
|
||||
_SpriteVBuffAddr tmp7;tmp1
|
||||
pha
|
||||
_TileStoreOffset tmp8;tmp2
|
||||
tax
|
||||
lda #TILE_SPRITE_BIT
|
||||
sta TileStore+TS_SPRITE_FLAG,x
|
||||
pla
|
||||
sta TileStore+TS_SPRITE_ADDR,x
|
||||
txa
|
||||
jsr _PushDirtyTile
|
||||
|
||||
:no_x_oflow
|
||||
lda tmp6
|
||||
beq :no_y_oflow
|
||||
|
||||
lda tmp1
|
||||
clc
|
||||
adc #8
|
||||
sta tmp1
|
||||
lda tmp2
|
||||
inc
|
||||
cmp #26
|
||||
bcc *+5
|
||||
lda #0
|
||||
sta tmp2
|
||||
|
||||
_SpriteVBuffAddr tmp3;tmp1
|
||||
pha
|
||||
_TileStoreOffset tmp4;tmp2
|
||||
tax
|
||||
lda #TILE_SPRITE_BIT
|
||||
sta TileStore+TS_SPRITE_FLAG,x
|
||||
pla
|
||||
sta TileStore+TS_SPRITE_ADDR,x
|
||||
txa
|
||||
jsr _PushDirtyTile
|
||||
|
||||
lda tmp5
|
||||
beq :no_y_oflow
|
||||
|
||||
_SpriteVBuffAddr tmp7;tmp1
|
||||
pha
|
||||
_TileStoreOffset tmp8;tmp2
|
||||
tax
|
||||
lda #TILE_SPRITE_BIT
|
||||
sta TileStore+TS_SPRITE_FLAG,x
|
||||
pla
|
||||
sta TileStore+TS_SPRITE_ADDR,x
|
||||
txa
|
||||
jsr _PushDirtyTile
|
||||
|
||||
:no_y_oflow
|
||||
ldx tmp0 ; Restore X register
|
||||
rts
|
||||
|
||||
; _GetTileAt
|
||||
@ -453,18 +499,18 @@ _AddSprite
|
||||
:open lda #SPRITE_STATUS_DIRTY
|
||||
sta _Sprites+SPRITE_STATUS,x ; Mark this sprite slot as occupied and that it needs to be drawn
|
||||
pla
|
||||
jsr _GetTileAddr
|
||||
jsr _GetTileAddr ; This applies the TILE_ID_MASK
|
||||
sta _Sprites+TILE_DATA_OFFSET,x
|
||||
|
||||
tya
|
||||
clc
|
||||
adc #NUM_BUFF_LINES ; The virtual buffer has 24 lines of off-screen space
|
||||
xba ; Each virtual scan line is 256 bytes wide for overdraw space
|
||||
clc
|
||||
adc 1,s ; Add the horizontal position
|
||||
tya ; Y coordinate
|
||||
sta _Sprites+SPRITE_Y,x
|
||||
|
||||
pla ; X coordinate
|
||||
sta _Sprites+SPRITE_X,x
|
||||
|
||||
jsr _GetSpriteVBuffAddr ; Preserves X-register
|
||||
sta _Sprites+VBUFF_ADDR,x
|
||||
|
||||
pla ; Pop off the saved value
|
||||
clc ; Mark that the sprite was successfully added
|
||||
txa ; And return the sprite ID
|
||||
rts
|
||||
@ -472,15 +518,22 @@ _AddSprite
|
||||
; X = x coordinate
|
||||
; Y = y coordinate
|
||||
GetSpriteVBuffAddr ENT
|
||||
jsr _GetSpriteVBuffAddr
|
||||
rtl
|
||||
|
||||
; A = x coordinate
|
||||
; Y = y coordinate
|
||||
_GetSpriteVBuffAddr
|
||||
pha
|
||||
tya
|
||||
clc
|
||||
adc #NUM_BUFF_LINES ; The virtual buffer has 24 lines of off-screen space
|
||||
xba ; Each virtual scan line is 256 bytes wide for overdraw space
|
||||
phx
|
||||
clc
|
||||
adc 1,s
|
||||
plx
|
||||
rtl
|
||||
sta 1,s
|
||||
pla
|
||||
rts
|
||||
|
||||
; Move a sprite to a new location. If the tile ID of the sprite needs to be changed, then
|
||||
; a full remove/add cycle needs to happen
|
||||
@ -518,11 +571,8 @@ _UpdateSprite
|
||||
tya ; Update the Y coordinate
|
||||
sta _Sprites+SPRITE_Y,x
|
||||
|
||||
clc
|
||||
adc #NUM_BUFF_LINES ; The virtual buffer has 24 lines of off-screen space
|
||||
xba ; Each virtual scan line is 256 bytes wide for overdraw space
|
||||
clc
|
||||
adc tmp0 ; Add the horizontal position
|
||||
lda tmp0
|
||||
jsr _GetSpriteVBuffAddr
|
||||
sta _Sprites+VBUFF_ADDR,x
|
||||
|
||||
rts
|
||||
|
@ -113,6 +113,8 @@ _RenderTile2
|
||||
lda TileStore+TS_TILE_ID,y ; build the finalized tile descriptor
|
||||
ora TileStore+TS_SPRITE_FLAG,y
|
||||
bpl :nosprite ; save a few cycles on average -- the sprite flag is $8000, so easy bpl/bmi test
|
||||
tyx
|
||||
stz TileStore+TS_SPRITE_FLAG,x ; clear the sprite flag
|
||||
ldx TileStore+TS_SPRITE_ADDR,y
|
||||
stx _SPR_X_REG
|
||||
|
||||
|
@ -5,6 +5,7 @@
|
||||
; there is no way to do everything inline, so a composite tile is created on the fly and written to
|
||||
; a direct page buffer. This direct page buffer is then used to render the tile.
|
||||
_TBSolidSpriteTile_00
|
||||
ldx #45*128
|
||||
jsr _TBCopyTileDataToCBuff ; Copy the tile into the compositing buffer (using correct x-register)
|
||||
jsr _TBApplySpriteData ; Overlay the data form the sprite plane (and copy into the code field)
|
||||
jmp _TBFillPEAOpcode ; Fill in the code field opcodes
|
||||
|
Loading…
Reference in New Issue
Block a user