mirror of
https://github.com/lscharen/iigs-game-engine.git
synced 2025-01-29 15:33:52 +00:00
Background rendering again
This commit is contained in:
Lucas Scharenbroich
parent
95572fbf49
commit
bb83e7f7c5
@ -53,36 +53,35 @@ DOWN_ARROW equ $0A
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SPRITE_ID equ {SPRITE_16X16+1}
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OKTOROK equ {SPRITE_16X16+79}
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lda #SPRITE_ID ; 16x16 sprite
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ldx PlayerX
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ldy PlayerY
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jsl AddSprite
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bcc :sprite_ok
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brl Exit ; If we could not allocate a sprite, exit
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:sprite_ok
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sta PlayerID
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brl Exit
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; lda #SPRITE_ID ; 16x16 sprite
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; ldx PlayerX
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; ldy PlayerY
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; jsl AddSprite
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; bcc :sprite_ok
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; brl Exit ; If we could not allocate a sprite, exit
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;:sprite_ok
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; sta PlayerID
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; Add 4 octoroks
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lda #OKTOROK
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ldx #32
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ldy #48
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jsl AddSprite
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; lda #OKTOROK
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; ldx #32
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; ldy #48
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; jsl AddSprite
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lda #OKTOROK
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ldx #96
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ldy #32
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jsl AddSprite
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; lda #OKTOROK
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; ldx #96
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; ldy #32
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; jsl AddSprite
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lda #OKTOROK
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ldx #56
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ldy #96
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jsl AddSprite
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; lda #OKTOROK
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; ldx #56
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; ldy #96
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; jsl AddSprite
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lda #OKTOROK
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ldx #72
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ldy #96
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jsl AddSprite
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; lda #OKTOROK
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; ldx #72
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; ldy #96
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; jsl AddSprite
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; Draw the initial screen
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@ -90,6 +89,7 @@ OKTOROK equ {SPRITE_16X16+79}
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tsb DirtyBits
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jsl Render
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; Set up a very specific test. First, we draw a sprite into the sprite plane, and then
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; leave it alone. We are just testing the ability to merge sprite plane data into
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; the play field tiles.
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@ -122,7 +122,8 @@ EvtLoop
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bne :not_q
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brl Exit
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:not_q
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brl EvtLoop
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cmp #'d'
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bne :not_d
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inc PlayerX
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@ -158,25 +158,6 @@ asr8 mac
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ror
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<<<
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; Inline macros for fast calculation of some internal values
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_TileStoreOffset mac
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lda ]2
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asl
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tay
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lda ]1
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asl ; Assume in range, so asl puts a 0 bit into the carry
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adc TileStoreYTable,y
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<<<
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_TileStoreOffsetX mac
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lda ]2
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asl
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tax
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lda ]1
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asl ; Assume in range, so asl puts a 0 bit into the carry
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adc TileStoreYTable,x
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<<<
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; Macro to define script steps
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ScriptStep MAC
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IF #=]5
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@ -57,7 +57,6 @@ GetTileAddr EXT
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PushDirtyTile EXT ; A = address from GetTileStoreOffset, marks as dirty (will not mark the same tile more than once)
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PopDirtyTile EXT ; No args, returns Y with tile store offset of the dirty tile
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ApplyTiles EXT ; Drain the dirty tile queue and call RenderTile on each
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RenderTile EXT ; Y = address from GetTileStoreOffset
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GetTileStoreOffset EXT ; X = column, Y = row
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TileStore EXT ; Tile store internal data structure
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34
src/Render.s
34
src/Render.s
@ -90,7 +90,7 @@ _Render
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; The code fields are locked in now and ready to be rendered
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jsr _ShadowOff
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; jsr _ShadowOff
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; Shadowing is turned off. Render all of the scan lines that need a second pass. One
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; optimization that can be done here is that the lines can be rendered in any order
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@ -102,27 +102,27 @@ _Render
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; Turn shadowing back on
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jsr _ShadowOn
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; jsr _ShadowOn
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; Now render all of the remaining lines in top-to-bottom (or bottom-to-top) order
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lda ScreenY0 ; pass the address of the first line of the overlay
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clc
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adc #0
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asl
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tax
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lda ScreenAddr,x
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clc
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adc ScreenX0
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; lda ScreenY0 ; pass the address of the first line of the overlay
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; clc
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; adc #0
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; asl
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; tax
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; lda ScreenAddr,x
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; clc
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; adc ScreenX0
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; jsl Overlay
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ldx #0 ; Blit the full virtual buffer to the screen
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ldy ScreenHeight
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jsr _BltRange
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; ldx #0
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; ldy ScreenHeight
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; jsr _BltSCB
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ldx #0
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ldy ScreenHeight
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jsr _BltSCB
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lda StartY ; Restore the fields back to their original state
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ldx ScreenHeight
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@ -139,10 +139,10 @@ _Render
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sta OldBG1StartX
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stz DirtyBits
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stz LastRender
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stz LastRender ; Mark that a full render was just performed
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rts
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; This is a specialized redner function that only updated the dirty tiles *and* draws them
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; This is a specialized render function that only updates the dirty tiles *and* draws them
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; directly onto the SHR graphics buffer. The playfield is not used at all. In some way, this
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; ignores almost all of the capabilities of GTE, but it does provide a convenient way to use
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; the sprite subsystem + tile attributes for single-screen games which should be able to run
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@ -207,7 +207,7 @@ _RenderDirtyTile
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xba
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tax
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ldal DirtyTileSpriteProcs,x
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sta :tiledisp+1
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stal :tiledisp+1
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bra :sprite
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:nosprite
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@ -216,7 +216,7 @@ _RenderDirtyTile
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xba
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tax
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ldal DirtyTileProcs,x ; load and patch in the appropriate subroutine
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sta :tiledisp+1
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stal :tiledisp+1
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:sprite
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ldx TileStore+TS_TILE_ADDR,y ; load the address of this tile's data (pre-calculated)
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211
src/Sprite.s
211
src/Sprite.s
@ -1,49 +1,6 @@
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; Functions for sprite handling. Mostly maintains the sprite list and provides
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; utility functions to calculate sprite/tile intersections
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;
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; The sprite plane actually covers two banks so that more than 32K can be used as a virtual
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; screen buffer. In order to be able to draw sprites offscreen, the virtual screen must be
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; wider and taller than the physical graphics screen.
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;
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; NOTE: It may be posible to remove the sprite plane banks in the future and render directly from
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; some small per-sprite graphic buffers. This would eliminate the need to erase/draw in
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; the sprite planes and all drawing would go directly to the backing tiles. Need to
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; figure out an efficient way to fall back when sprites are overlapping, though.
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;
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; All of the erasing must happen in an initial phase, because erasing a sprite could cause
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; other sprites to be marked as "DAMAGED" which means they need to be drawn (similar to NEW state)
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; What really has to happen in the various cases:
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;
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; When a sprite is added, it needs to
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; * draw into the sprite buffer
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; * add itself to the TS_SPRITE_FLAG bitfield on the tiles it occupies
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; * mark the tiles it occupies as dirty
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;
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; When a sprite is updated (Tile ID or H/V flip flags), it needs to
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; * erase itself from the sprite buffer
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; * draw into the sprite buffer
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; * mark the tiles it occupies as dirty
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; * mark other sprites it intersects as DAMAGED
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;
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; When a sprite is moved, it needs to
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; * erase itself from the sprite buffer at the old locations
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; * remove itself from the TS_SPRITE_FLAG bitfields on the tiles it occupied
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; * mark sprites that intersect as DAMAGED
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; * draw into the sprite buffer at the new location
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; * add itself to the TS_SPRITE_FLAG bitfield on the tiles it now occupies
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; * mark the tiles it occupied as dirty
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; * mark other sprites it intersects as DAMAGED
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;
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; When a sprite is removed, it needs to
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; * erase itself from the sprite buffer at the old locations
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; * remove itself from the TS_SPRITE_FLAG bitfields on the tiles it occupied
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; * mark other sprites it intersects as DAMAGED
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;
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; The reason that things are broken into phases is that we have to handle all of the erasing first,
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; set dirty tiles, identify DAMAGED sprites, and THEN perform the drawing. It is not possible to
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; just do each sprite one at a time.
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;
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; Initialize the sprite data and mask banks (all data = $0000, all masks = $FFFF)
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InitSprites
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ldx #$FFFE
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@ -92,6 +49,89 @@ VBUFF_SPRITE_START equ {8*VBUFF_TILE_ROW_BYTES}+4
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jsr _CacheSpriteBanks
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rts
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; Add a new sprite to the rendering pipeline
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;
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; The tile id in the range 0 - 511. The top 7 bits are used as sprite control bits
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;
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; Bit 9 : Horizontal flip.
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; Bit 10 : Vertical flip.
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; Bits 11 - 12 : Sprite Size Selector
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; 00 - 8x8 (1x1 tile)
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; 01 - 8x16 (1x2 tiles)
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; 10 - 16x8 (2x1 tiles)
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; 11 - 16x16 (2x2 tiles)
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; Bit 13 : Reserved. Must be zero.
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; Bit 14 : Reserved. Must be zero.
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; Bit 15 : Low Sprite priority. Draws behind high priority tiles.
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;
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; When a sprite has a size > 8x8, the horizontal tiles are taken from the next tile index and
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; the vertical tiles are taken from tileId + 32. This is why tile sheets should be saved
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; with a width of 256 pixels.
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;
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; Single sprite are limited to 24 lines high because there are 28 lines of padding above and below the
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; sprite plane buffers, so a sprite that is 32 lines high could overflow the drawing area.
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;
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; A = tileId + flags
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; X = x position
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; Y = y position
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AddSprite ENT
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phb
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phk
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plb
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jsr _AddSprite
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plb
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rtl
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_AddSprite
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phx ; Save the horizontal position
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ldx _NextOpenSlot ; Get the next free sprite slot index
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bpl :open ; A negative number means we are full
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plx ; Early out
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sec ; Signal that no sprite slot was available
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rts
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:open
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sta _Sprites+SPRITE_ID,x ; Keep a copy of the full descriptor
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jsr _GetTileAddr ; This applies the TILE_ID_MASK
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sta _Sprites+TILE_DATA_OFFSET,x
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lda #SPRITE_STATUS_OCCUPIED+SPRITE_STATUS_ADDED
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sta _Sprites+SPRITE_STATUS,x
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tya
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sta _Sprites+SPRITE_Y,x ; Y coordinate
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pla ; X coordinate
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sta _Sprites+SPRITE_X,x
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jsr _PrecalcAllSpriteInfo ; Cache sprite property values (simple stuff)
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jsr _DrawSpriteSheet ; Render the sprite into internal space
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; Mark the dirty bit to indicate that the active sprite list needs to be rebuilt in the next
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; render call
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lda #DIRTY_BIT_SPRITE_ARRAY
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tsb DirtyBits
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lda _SpriteBits,x ; Get the bit flag for this sprite slot
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tsb SpriteMap ; Mark it in the sprite map bit field
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txa ; And return the sprite ID
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clc ; Mark that the sprite was successfully added
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; We can only get to this point if there was an open slot, so we know we're not at the
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; end of the list yet.
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ldx _OpenListHead
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inx
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inx
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stx _OpenListHead
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ldy _OpenList,x ; If this is the end, then the sentinel value will
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sty _NextOpenSlot ; get stored into _NextOpenSlot
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rts
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; Run through the list of tile store offsets that this sprite was last drawn into and mark
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; those tiles as dirty. The largest number of tiles that a sprite could possibly cover is 20
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; (an unaligned 4x3 sprite), covering a 5x4 area of play field tiles.
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@ -538,91 +578,6 @@ SPRITE_PLANE_SPAN equ 52 ; 256
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; adc tmp15
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; rts
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; Add a new sprite to the rendering pipeline
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;
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; The tile id in the range 0 - 511. The top 7 bits are used as sprite control bits
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;
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; Bit 9 : Horizontal flip.
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; Bit 10 : Vertical flip.
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; Bits 11 - 12 : Sprite Size Selector
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; 00 - 8x8 (1x1 tile)
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; 01 - 8x16 (1x2 tiles)
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; 10 - 16x8 (2x1 tiles)
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; 11 - 16x16 (2x2 tiles)
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; Bit 13 : Reserved. Must be zero.
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; Bit 14 : Reserved. Must be zero.
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; Bit 15 : Low Sprite priority. Draws behind high priority tiles.
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;
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; When a sprite has a size > 8x8, the horizontal tiles are taken from the next tile index and
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; the vertical tiles are taken from tileId + 32. This is why tile sheets should be saved
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; with a width of 256 pixels.
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;
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; Single sprite are limited to 24 lines high because there are 28 lines of padding above and below the
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; sprite plane buffers, so a sprite that is 32 lines high could overflow the drawing area.
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;
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; A = tileId + flags
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; X = x position
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; Y = y position
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AddSprite ENT
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phb
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phk
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plb
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jsr _AddSprite
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plb
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rtl
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_AddSprite
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phx ; Save the horizontal position
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ldx _NextOpenSlot ; Get the next free sprite slot index
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bpl :open ; A negative number means we are full
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plx ; Early out
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sec ; Signal that no sprite slot was available
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rts
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:open
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sta _Sprites+SPRITE_ID,x ; Keep a copy of the full descriptor
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jsr _GetTileAddr ; This applies the TILE_ID_MASK
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sta _Sprites+TILE_DATA_OFFSET,x
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lda #SPRITE_STATUS_OCCUPIED+SPRITE_STATUS_ADDED
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sta _Sprites+SPRITE_STATUS,x
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tya
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sta _Sprites+SPRITE_Y,x ; Y coordinate
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pla ; X coordinate
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sta _Sprites+SPRITE_X,x
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; jsr _GetSpriteVBuffAddrTmp
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; sta _Sprites+VBUFF_ADDR,x ; This is now pre-calculated since each sprite slot gets a fixed location
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jsr _PrecalcAllSpriteInfo ; Cache sprite property values (simple stuff)
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jsr _DrawSpriteSheet ; Render the sprite into internal space
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; Mark the dirty bit to indicate that the active sprite list needs to be rebuilt in the next
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; render call
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lda #DIRTY_BIT_SPRITE_ARRAY
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tsb DirtyBits
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lda _SpriteBits,x ; Get the bit flag for this sprite slot
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tsb SpriteMap ; Mark it in the sprite map bit field
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txa ; And return the sprite ID
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clc ; Mark that the sprite was successfully added
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; We can only get to this point if there was an open slot, so we know we're not at the
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; end of the list yet.
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ldx _OpenListHead
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inx
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inx
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stx _OpenListHead
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ldy _OpenList,x ; If this is the end, then the sentinel value will
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sty _NextOpenSlot ; get stored into _NextOpenSlot
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rts
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; Precalculate some cached values for a sprite. These are *only* to make other part of code,
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; specifically the draw/erase routines more efficient.
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;
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@ -318,21 +318,6 @@ _MarkDirtySprite
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rts
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; Begin List of subroutines to mark each tile offset
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;
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; If we had a double-sized 2D array to be able to look up the tile store address without
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; adding rows and column, we could save ~6 cycles per tile
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; If all that is needed is to record the Tile Store offset for the sprite and delay any
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; actual calculations, then we just need to do
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;
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; lda TileStore2DArray,x
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; sta _Sprites+TILE_STORE_ADDR_0,y
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; lda TileStore2DArray+2,x
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; sta _Sprites+TILE_STORE_ADDR_1,y
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; lda TileStore2DArray+41,x
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; sta _Sprites+TILE_STORE_ADDR_2,y
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; ...
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:mark_0_0
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ldx RowTop
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lda ColLeft
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@ -17,7 +17,7 @@
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; The table values are pre-reversed so that loop can go in logical order 0, 2, 4, ...
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; and the resulting offsets will map to the code instructions in right-to-left order.
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;
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; Remember, because the data is pushed on to the stask, the last instruction, which is
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; Remember, because the data is pushed on to the stack, the last instruction, which is
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; in the highest memory location, pushed data that apepars on the left edge of the screen.
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PER_TILE_SIZE equ 3
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]step equ 0
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@ -238,18 +238,6 @@ TileStoreYTable ENT
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]step = ]step+{41*2}
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--^
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;TileStore2DYTable
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;]step equ 0
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; lup 26
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; dw ]step
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;]step = ]step+{41*2*2}
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; --^
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;]step equ 0
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; lup 26
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; dw ]step
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;]step = ]step+{41*2*2}
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; --^
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; Create a table to look up the "next" column with modulo wraparound. Basically a[i] = i
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; and the table is double-length. Use constant offsets to pick an amount to advance
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NextCol
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@ -103,14 +103,6 @@ _RenderTileBG1
|
||||
; Store record contains all of the low-level information that's needed to call the renderer.
|
||||
;
|
||||
; Y = address of tile
|
||||
RenderTile ENT
|
||||
phb
|
||||
phk
|
||||
plb
|
||||
jsr _RenderTile2
|
||||
plb
|
||||
rtl
|
||||
|
||||
_RenderTile2
|
||||
pea >TileStore ; Need that addressing flexibility here. Callers responsible for restoring bank reg
|
||||
plb
|
||||
@ -118,9 +110,9 @@ _RenderTile2
|
||||
|
||||
lda TileStore+TS_TILE_ID,y ; build the finalized tile descriptor
|
||||
ldx TileStore+TS_SPRITE_FLAG,y ; This is a bitfield of all the sprites that intersect this tile, only care if non-zero or not
|
||||
beq :nosprite
|
||||
; beq :nosprite
|
||||
|
||||
ora #TILE_SPRITE_BIT
|
||||
; ora #TILE_SPRITE_BIT
|
||||
; ldx TileStore+TS_SPRITE_ADDR,y ; TODO: collapse sprites
|
||||
; stx _SPR_X_REG
|
||||
|
||||
@ -129,8 +121,8 @@ _RenderTile2
|
||||
and #TILE_CTRL_MASK
|
||||
xba
|
||||
tax
|
||||
lda TileProcs,x ; load and patch in the appropriate subroutine
|
||||
sta :tiledisp+1
|
||||
ldal TileProcs,x ; load and patch in the appropriate subroutine
|
||||
stal :tiledisp+1
|
||||
|
||||
ldx TileStore+TS_TILE_ADDR,y ; load the address of this tile's data (pre-calculated)
|
||||
|
||||
@ -541,6 +533,7 @@ InitTiles
|
||||
:col equ tmp0
|
||||
:row equ tmp1
|
||||
:vbuff equ tmp2
|
||||
|
||||
; Fill in the TileStoreYTable. This is just a table of offsets into the Tile Store for each row. There
|
||||
; are 26 rows with a stride of 41
|
||||
ldy #0
|
||||
@ -554,36 +547,6 @@ InitTiles
|
||||
cpy #26*2
|
||||
bcc :yloop
|
||||
|
||||
; Fill in the TileStore2DLookup array. This is a full array lookup for the entire tile store space. Eventually
|
||||
; we can remove TileStoreYTable and free up a bit of space.
|
||||
lda #0
|
||||
tay
|
||||
tax
|
||||
:xyloop
|
||||
sta TileStoreYTable,y
|
||||
sta TileStoreYTable+{2*41},y
|
||||
sta TileStoreYTable+{4*41*26},y
|
||||
sta TileStoreYTable+{4*41*26}+{2*41},y
|
||||
|
||||
inc ; Advance to the next offset value
|
||||
inc
|
||||
|
||||
iny ; Advance to the next table location
|
||||
iny
|
||||
|
||||
inx ; Increment the column counter
|
||||
cpx #41 ; If we haven't filled an entire row, keep going
|
||||
bcc :xyloop
|
||||
|
||||
ldx #0 ; reset the column counter
|
||||
tya
|
||||
clc
|
||||
adc #2*26 ; skip over the repeated values in this row and to to the next row start
|
||||
tay
|
||||
|
||||
cpy #4*41*26 ; Did we finish the last row, if not go back for more
|
||||
bcc :xyloop
|
||||
|
||||
; Next, initialize the Tile Store itself
|
||||
|
||||
ldx #TILE_STORE_SIZE-2
|
||||
@ -741,23 +704,13 @@ _PushDirtyTileX
|
||||
bpl :occupied2
|
||||
|
||||
txa ; any non-negative value will work, this saves work below
|
||||
stal TileStore+TS_DIRTY,x ; and is 1 cycle fater than loading a constanct value
|
||||
stal TileStore+TS_DIRTY,x ; and is 1 cycle faster than loading a constant value
|
||||
|
||||
; txa
|
||||
ldx DirtyTileCount ; 5
|
||||
sta DirtyTiles,x ; 5
|
||||
|
||||
inx
|
||||
inx
|
||||
stx DirtyTileCount
|
||||
|
||||
; Same speed, but preserved the X register
|
||||
; sta (DirtyTiles) ; 6
|
||||
; lda DirtyTiles ; 4
|
||||
; inc ; 2
|
||||
; inc ; 2
|
||||
; sta DirtyTiles ; 4
|
||||
|
||||
rts
|
||||
:occupied2
|
||||
txa ; Make sure TileStore offset is returned in the accumulator
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user