mirror of
https://github.com/lscharen/iigs-game-engine.git
synced 2025-02-06 06:29:57 +00:00
Commit to a huge unrolled loop to do bitfield -> render function
This commit is contained in:
Lucas Scharenbroich
parent
ef620e48a3
commit
df0d0ccada
@ -54,35 +54,35 @@ 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 PlayerX
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xba
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ora PlayerY
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tay ; (x, y) position
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ldx #0
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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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; Add 4 octoroks
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lda #OKTOROK
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ldx #1
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ldy #{32*256}+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 #2
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ldy #{32*256}+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 #3
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ldy #{96*256}+56
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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 #4
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ldy #{96*256}+72
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jsl AddSprite
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; Draw the initial screen
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@ -176,6 +176,32 @@ EvtLoop
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ldy PlayerY
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jsl MoveSprite ; Move the sprite to the current position
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; Based on the frame count, move an oktorok
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jsl GetVBLTicks
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pha
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and #$0003
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asl
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tax
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pla
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and #$007C
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lsr
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tay
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lda OktorokX,x
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clc
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adc OktorokDelta,y
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phx
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ldy OktorokY,x
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tax
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pla
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inc
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inc
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jsl MoveSprite
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; Let's see what it looks like!
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lda vsync
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@ -185,7 +211,7 @@ EvtLoop
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bcc :vsyncloop
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sec
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sbc ScreenY0
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cmp #8
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cmp #4
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bcs :vsyncloop ; Wait until we're within the top 8 scanlines
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lda #1
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jsl SetBorderColor
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@ -297,6 +323,9 @@ PlayerID ds 2
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PlayerX ds 2
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PlayerY ds 2
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OktorokX dw 32,32,96,96
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OktorokY dw 48,96,56,72
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OktorokDelta dw 0,1,2,3,4,5,6,7,6,5,4,3,2,1,0,-1,-2,-3,-4,-5,-6,-7,-8,-7,-6,-5,-4,-3,-2,-1,0,0,0
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TransitionX ds 2
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TransitionY ds 2
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913
src/Render.s
913
src/Render.s
@ -1,58 +1,16 @@
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; Renders a frame of animation
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;
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; The rendering engine is built around the idea of compositing all of the moving components
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; on to the Bank 01 graphics buffer and then revealing everything in a single, vertical pass.
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;
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; If there was just a scrolling screen with no sprites, the screen would just get rendered
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; in a single pass, but it gets more complicated with sprites and various effects.
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;
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; Here is the high-level pipeline:
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;
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; 1. Identify row ranges with effects. These effects can be sprites or user-defined overlays
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; 2. Turn shadowing off
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; 3. Render the background for each effect row range (in any order)
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; 4. Render the sprites (in any order)
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; 5. Turn shadowing on
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; 6. Render the background for each non-effect row, a pei slam for sprite rows, and
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; the user-defined overlays (in sorted order)
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;
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; As a concrete example, consider:
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;
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; Rows 0 - 9 have a user-defined floating overlay for a score board
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; Rows 10 - 100 are background only
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; Rows 101 - 120 have one or more sprites
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; Rows 121 - 140 are background only
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; Rows 141 - 159 have a user-defined solid overlay for an animated platform
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;
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; A floating overlay means that some background data bay show through. A solid overlay means that
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; the user-defined data covers the entire scan line.
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;
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; The renderer would proceed as:
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;
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; - shadow off
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; - render_background(0, 10)
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; - render_background(101, 121)
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; - render_sprites()
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; - shadow_on
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; - render_user_overlay_1()
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; - render_background(10, 101)
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; - pei_slam(101, 121)
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; - render_background(121, 141)
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; - render_user_overlay_2()
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;
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; Generally speaking, a PEI Slam is faster that trying to do any sort of dirty-rectangle update by
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; tracking sprinte bounding boxes. But, if an application would benefit from skipping some background
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; drawing on sprite rows, that can be handled by using the low level routines to control the left/right
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; edges of the rendered play field.
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; The render function is the point of committment -- most of the APIs that set sprites and
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; update coordinates are lazy; they simply save the value and set a dirty flag in the
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; update coordinates are lazy; they simply save their values and set a dirty flag in the
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; DirtyBits word.
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;
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; This function examines the dirty bits and actually performs the work to update the code field
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; and internal data structure to properly render the play field. Then the update pipeline is
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; executed.
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;
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; Everything is composited into the tiles in the playfield and then the screen is rendered in
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; a single pass.
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Render ENT
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phb
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phk
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@ -122,9 +80,9 @@ _Render
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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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@ -149,6 +107,35 @@ _Render
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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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; close to 60 fps.
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;
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; Because we are register starved, there is a lot of inline code to quickly fetch the information
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; needed to render sprites appropriately. If there was a way to efficiently maintain an ordered
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; and compact array of per-tile VBUFF addresses, rather than the current sparse array, then
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; the sprite handling code could be significantly streamlined. A note for anyone attempting
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; this optimization:
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;
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; The _MarkDirtyTiles simply stores a sprite's per-tile VBUFF address and marks the tile
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; as being occupied by the sprite with just 4 instructions
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;
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; sta (vbuff_array_ptr),y
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; lda TileStore+TS_SPRITE_FLAG,x
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; ora SpriteBit,y
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; sta TileStore+TS_SPRITE_FLAG,x
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;
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; Then, we have an unrolled loop that does repeated tests of
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;
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; lsr
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; bcc *+
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; lda vbuff_array_ptr,y
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; sta spriteVBuffArr
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;
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; The only gain to be had is if the sprites that are marked are in the high bits and there are no low-index
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; sprites. Skipping over N bits of the SPRITE_FLAG takes only 5*N cycles. So, on average, we might waste
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; 40 cycles looking for the proper bit.
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;
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; Any improvement to the existing code would need to be able to maintain a data structure and get the final
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; values into the spriteVBuffArr for a total cost of under 75 cycles per tile.
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RenderDirty ENT
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phb
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phk
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@ -157,7 +144,7 @@ RenderDirty ENT
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plb
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rtl
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; In this renderer, we assume that thwere is no scrolling, so no need to update any information about
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; In this renderer, we assume that there is no scrolling, so no need to update any information about
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; the BG0/BG1 positions
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_RenderDirty
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lda LastRender ; If the full renderer was last called, we assume that
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@ -218,13 +205,6 @@ _RenderDirtyTile
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lda TileStore+TS_SCREEN_ADDR,y ; Get the on-screen address of this tile
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tay
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; pha
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; lda TileStore+TS_WORD_OFFSET,y ; We don't support this in dirty rendering mode
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; ply
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; pea $0101
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; plb
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plb ; set the bank
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; B is set to Bank 01
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@ -234,42 +214,465 @@ _RenderDirtyTile
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:tiledisp jmp $0000 ; render the tile
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; Use some temporary space for the spriteIdx array (maximum of 4 entries)
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stkSave equ tmp9
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screenAddr equ tmp10
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tileAddr equ tmp11
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spriteIdx equ tmp12
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; Handler for the sprite path
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dirty_sprite
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pei TileStoreBankAndTileDataBank ; Special value that has the TileStore bank in LSB and TileData bank in MSB
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plb
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; Cache a couple of values into the direct page, but preserve the Accumulator
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ldy TileStore+TS_TILE_ADDR,x ; load the address of this tile's data (pre-calculated)
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sty tileAddr
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ldy TileStore+TS_SCREEN_ADDR,x ; Get the on-screen address of this tile
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sty screenAddr
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; Now do all of the deferred work of actually drawing the sprites. We put considerable effort into
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; figuring out if there is only one sprite or more than one since we optimize the former case as it
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; is very common and can be done significantly faster.
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;
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; We use the logic operation of A & (A - 1) which removes the least-significant set bit position. If
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; this results in a zero value, then we know that there is only a single sprite and can move to an
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; optimized routine.
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; This is a big, unrolled chunk of code that packs the VBUFF addresses for the sprite positions marked
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; in the bitfield into the spriteIdx array and then jumps to an optimized rendering function based on
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; the number of sprites on the tile.
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;
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; After each set bit is identified, we check to see if that was the last one and immediately exit. Since
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; a maximum of 4 sprites are processed per tile, this only results in (at most) 4 extra branch instructions.
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dec
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and TileStore+TS_SPRITE_FLAG,x
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bne multi_sprite
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ldy TileStore+TS_VBUFF_ARRAY_ADDR,x ; base address of the VBUFF sprite address array for this tile
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; Now we are on the fast path. There is only one sprite at this tile, so load the cached VBUFF address
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; from the TileStore data structure. This is only guaranteed to be a VBUFF address from one of the
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; sprites at the tile, but if there is only one, it's the value we want.
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lsr
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bcc :loop_0_bit_1
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ldx: $0000,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_1
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jmp BlitOneSprite
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lda TileStore+TS_LAST_VBUFF,x
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pha
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ldy TileStore+TS_TILE_ADDR,x ; load the address of this tile's data
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lda TileStore+TS_SCREEN_ADDR,x ; Get the on-screen address of this tile
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plx ; Set the vbuff address
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plb
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jmp FastBlit
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:loop_0_bit_1 lsr
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bcc :loop_0_bit_2
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ldx: $0002,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_2
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jmp BlitOneSprite
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; This is the code path to handle tile with multiple, overlapping sprites.
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multi_sprite
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plb
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rts ; TBD
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:loop_0_bit_2 lsr
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bcc :loop_0_bit_3
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ldx: $0004,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_3
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jmp BlitOneSprite
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:loop_0_bit_3 lsr
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bcc :loop_0_bit_4
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ldx: $0006,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_4
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jmp BlitOneSprite
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:loop_0_bit_4 lsr
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bcc :loop_0_bit_5
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ldx: $0008,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_5
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jmp BlitOneSprite
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:loop_0_bit_5 lsr
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bcc :loop_0_bit_6
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ldx: $000A,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_6
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jmp BlitOneSprite
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:loop_0_bit_6 lsr
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bcc :loop_0_bit_7
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ldx: $000C,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_7
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jmp BlitOneSprite
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:loop_0_bit_7 lsr
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bcc :loop_0_bit_8
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ldx: $000E,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_8
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jmp BlitOneSprite
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:loop_0_bit_8 lsr
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bcc :loop_0_bit_9
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ldx: $0010,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_9
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jmp BlitOneSprite
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:loop_0_bit_9 lsr
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bcc :loop_0_bit_10
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ldx: $0012,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_10
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jmp BlitOneSprite
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:loop_0_bit_10 lsr
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bcc :loop_0_bit_11
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ldx: $0014,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_11
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jmp BlitOneSprite
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:loop_0_bit_11 lsr
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bcc :loop_0_bit_12
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ldx: $0016,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_12
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jmp BlitOneSprite
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:loop_0_bit_12 lsr
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bcc :loop_0_bit_13
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ldx: $0018,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_13
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jmp BlitOneSprite
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:loop_0_bit_13 lsr
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bcc :loop_0_bit_14
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ldx: $001A,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_14
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jmp BlitOneSprite
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:loop_0_bit_14 lsr
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bcc :loop_0_bit_15
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ldx: $001C,y
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stx spriteIdx
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cmp #0
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jne :loop_1_bit_15
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jmp BlitOneSprite
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; If we get to bit 15, then it *must* be a bit that is set
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:loop_0_bit_15 ldx: $001E,y
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stx spriteIdx
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jmp BlitOneSprite
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:loop_1_bit_1 lsr
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bcc :loop_1_bit_2
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ldx: $0002,y
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stx spriteIdx+2
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cmp #0
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jne :loop_2_bit_2
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jmp BlitTwoSprites
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:loop_1_bit_2 lsr
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bcc :loop_1_bit_3
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ldx: $0004,y
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stx spriteIdx+2
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cmp #0
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jne :loop_2_bit_3
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jmp BlitTwoSprites
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:loop_1_bit_3 lsr
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bcc :loop_1_bit_4
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ldx: $0006,y
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stx spriteIdx+2
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cmp #0
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jne :loop_2_bit_4
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jmp BlitTwoSprites
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:loop_1_bit_4 lsr
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bcc :loop_1_bit_5
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ldx: $0008,y
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stx spriteIdx+2
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cmp #0
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jne :loop_2_bit_5
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jmp BlitTwoSprites
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:loop_1_bit_5 lsr
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bcc :loop_1_bit_6
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ldx: $000A,y
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stx spriteIdx+2
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cmp #0
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jne :loop_2_bit_6
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jmp BlitTwoSprites
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:loop_1_bit_6 lsr
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bcc :loop_1_bit_7
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ldx: $000C,y
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stx spriteIdx+2
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cmp #0
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jne :loop_2_bit_7
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jmp BlitTwoSprites
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:loop_1_bit_7 lsr
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bcc :loop_1_bit_8
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ldx: $000E,y
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stx spriteIdx+2
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cmp #0
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jne :loop_2_bit_8
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jmp BlitTwoSprites
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:loop_1_bit_8 lsr
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bcc :loop_1_bit_9
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ldx: $0010,y
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stx spriteIdx+2
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cmp #0
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jne :loop_2_bit_9
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jmp BlitTwoSprites
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:loop_1_bit_9 lsr
|
||||
bcc :loop_1_bit_10
|
||||
ldx: $0012,y
|
||||
stx spriteIdx+2
|
||||
cmp #0
|
||||
jne :loop_2_bit_10
|
||||
jmp BlitTwoSprites
|
||||
|
||||
:loop_1_bit_10 lsr
|
||||
bcc :loop_1_bit_11
|
||||
ldx: $0014,y
|
||||
stx spriteIdx+2
|
||||
cmp #0
|
||||
jne :loop_2_bit_11
|
||||
jmp BlitTwoSprites
|
||||
|
||||
:loop_1_bit_11 lsr
|
||||
bcc :loop_1_bit_12
|
||||
ldx: $0016,y
|
||||
stx spriteIdx+2
|
||||
cmp #0
|
||||
jne :loop_2_bit_12
|
||||
jmp BlitTwoSprites
|
||||
|
||||
:loop_1_bit_12 lsr
|
||||
bcc :loop_1_bit_13
|
||||
ldx: $0018,y
|
||||
stx spriteIdx+2
|
||||
cmp #0
|
||||
jne :loop_2_bit_13
|
||||
jmp BlitTwoSprites
|
||||
|
||||
:loop_1_bit_13 lsr
|
||||
bcc :loop_1_bit_14
|
||||
ldx: $001A,y
|
||||
stx spriteIdx+2
|
||||
cmp #0
|
||||
jne :loop_2_bit_14
|
||||
jmp BlitTwoSprites
|
||||
|
||||
:loop_1_bit_14 lsr
|
||||
bcc :loop_1_bit_15
|
||||
ldx: $001C,y
|
||||
stx spriteIdx+2
|
||||
cmp #0
|
||||
jne :loop_2_bit_15
|
||||
jmp BlitTwoSprites
|
||||
|
||||
:loop_1_bit_15 ldx: $001E,y
|
||||
stx spriteIdx+2
|
||||
jmp BlitTwoSprites
|
||||
|
||||
:loop_2_bit_2 lsr
|
||||
bcc :loop_2_bit_3
|
||||
ldx: $0004,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_3
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_3 lsr
|
||||
bcc :loop_2_bit_4
|
||||
ldx: $0006,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_4
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_4 lsr
|
||||
bcc :loop_2_bit_5
|
||||
ldx: $0008,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_5
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_5 lsr
|
||||
bcc :loop_2_bit_6
|
||||
ldx: $000A,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_6
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_6 lsr
|
||||
bcc :loop_2_bit_7
|
||||
ldx: $000C,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_7
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_7 lsr
|
||||
bcc :loop_2_bit_8
|
||||
ldx: $000E,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_8
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_8 lsr
|
||||
bcc :loop_2_bit_9
|
||||
ldx: $0010,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_9
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_9 lsr
|
||||
bcc :loop_2_bit_10
|
||||
ldx: $0012,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_10
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_10 lsr
|
||||
bcc :loop_2_bit_11
|
||||
ldx: $0014,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_11
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_11 lsr
|
||||
bcc :loop_2_bit_12
|
||||
ldx: $0016,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_12
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_12 lsr
|
||||
bcc :loop_2_bit_13
|
||||
ldx: $0018,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_13
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_13 lsr
|
||||
bcc :loop_2_bit_14
|
||||
ldx: $001A,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_14
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_14 lsr
|
||||
bcc :loop_2_bit_15
|
||||
ldx: $001C,y
|
||||
stx spriteIdx+4
|
||||
cmp #0
|
||||
jne :loop_3_bit_15
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_2_bit_15 ldx: $001E,y
|
||||
stx spriteIdx+4
|
||||
jmp BlitThreeSprites
|
||||
|
||||
:loop_3_bit_3 lsr
|
||||
bcc :loop_3_bit_4
|
||||
ldx $0006,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_4 lsr
|
||||
bcc :loop_3_bit_5
|
||||
ldx $0008,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_5 lsr
|
||||
bcc :loop_3_bit_6
|
||||
ldx $000A,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_6 lsr
|
||||
bcc :loop_3_bit_7
|
||||
ldx $000C,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_7 lsr
|
||||
bcc :loop_3_bit_8
|
||||
ldx $000E,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_8 lsr
|
||||
bcc :loop_3_bit_9
|
||||
ldx $0010,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_9 lsr
|
||||
bcc :loop_3_bit_10
|
||||
ldx $0012,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_10 lsr
|
||||
bcc :loop_3_bit_11
|
||||
ldx $0014,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_11 lsr
|
||||
bcc :loop_3_bit_12
|
||||
ldx $0016,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_12 lsr
|
||||
bcc :loop_3_bit_13
|
||||
ldx $0018,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_13 lsr
|
||||
bcc :loop_3_bit_14
|
||||
ldx $001A,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_14 lsr
|
||||
bcc :loop_3_bit_15
|
||||
ldx $001C,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
:loop_3_bit_15 ldx $001E,y
|
||||
stx spriteIdx+6
|
||||
jmp BlitFourSprites
|
||||
|
||||
DirtyTileProcs dw _TBDirtyTile_00,_TBDirtyTile_0H,_TBDirtyTile_V0,_TBDirtyTile_VH
|
||||
DirtyTileSpriteProcs dw _TBDirtySpriteTile_00,_TBDirtySpriteTile_0H,_TBDirtySpriteTile_V0,_TBDirtySpriteTile_VH
|
||||
;DirtyTileSpriteProcs dw _TBDirtySpriteTile_00,_TBDirtySpriteTile_0H,_TBDirtySpriteTile_V0,_TBDirtySpriteTile_VH
|
||||
|
||||
; Blit tiles directly to the screen.
|
||||
_TBDirtyTile_00
|
||||
@ -298,123 +701,201 @@ _TBDirtyTile_VH
|
||||
--^
|
||||
rts
|
||||
|
||||
_TBDirtySpriteTile_00
|
||||
_TBDirtySpriteTile_0H
|
||||
jsr _TBCopyTileDataToCBuff ; Copy the tile into the compositing buffer (using correct x-register)
|
||||
jmp _TBApplyDirtySpriteData ; Overlay the data from the sprite plane (and copy into the code field)
|
||||
|
||||
_TBDirtySpriteTile_V0
|
||||
_TBDirtySpriteTile_VH
|
||||
jsr _TBCopyTileDataToCBuffV
|
||||
jmp _TBApplyDirtySpriteData
|
||||
|
||||
|
||||
; Just copy in the data from the first sprite
|
||||
_TBApplyDirtySpriteData
|
||||
|
||||
_TBApplyDirtySpriteData0
|
||||
ldx _SPR_X_REG ; set to the unaligned tile block address in the sprite plane
|
||||
|
||||
]line equ 0
|
||||
lup 8
|
||||
lda blttmp+{]line*4}
|
||||
andl spritemask+{]line*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{]line*SPRITE_PLANE_SPAN},x
|
||||
sta: $0000+{]line*160},y
|
||||
|
||||
lda blttmp+{]line*4}+2
|
||||
andl spritemask+{]line*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{]line*SPRITE_PLANE_SPAN}+2,x
|
||||
sta: $0002+{]line*160},y
|
||||
]line equ ]line+1
|
||||
--^
|
||||
rts
|
||||
|
||||
; Input: A = bit field, assumed non-zero
|
||||
; Output: A = number of bits set
|
||||
; Side Effect: Fill in the ActiveSprite list with sprite indices.
|
||||
;
|
||||
; We try very hard to be fast and clever here. Early out, keeping everything in
|
||||
; registers when possible, and reducing overhead.
|
||||
|
||||
spriteIdx equ tmp12
|
||||
BuildActiveSpriteArray
|
||||
|
||||
; Push a sentinel value on the stack so we know where to end later. We con't count during the
|
||||
; initial process, because the Z flag needs to be maintained and almost evey opcode affects it.
|
||||
|
||||
; cmp lastActiveValue ; Assume that there is a decent chance of having the same
|
||||
; beq early_out ; sprite bitfield in consecutive dirty tiles. Saves a lot.
|
||||
|
||||
tsx ; save the stack pointer
|
||||
pea $FFFF ; sentinel value
|
||||
|
||||
; This first loop scans the bits in the accumulator and pushed a sprite index onto the stack. We
|
||||
; could push any constanct, which gives us some flexibility. This only works because the PEA
|
||||
; instruction does not affect any register. We also check to see if the acumulator is zero as
|
||||
; an early-out test, but only do that every 4 bits in order to amortize the overhead a bit.
|
||||
|
||||
]step equ 0
|
||||
lup 4
|
||||
lsr
|
||||
bcc :skip_1
|
||||
pea ]step
|
||||
:skip_1 lsr
|
||||
bcc :skip_2
|
||||
pea ]step+2
|
||||
:skip_2 lsr
|
||||
bcc :skip_3
|
||||
pea ]step+4
|
||||
:skip_3 lsr
|
||||
bcc :skip_4
|
||||
pea ]step+6
|
||||
:skip_4 beq :end_1
|
||||
]step equ ]step+8
|
||||
--^
|
||||
:end_1
|
||||
|
||||
; This second loop pops values off of the stack and places them into a linear array. We also
|
||||
; set the count on exit. As an optimization / restriction, we only allow up to four overlapping
|
||||
; sprites. This is similar to the NES/C64 "8 sprites per line" restriction.
|
||||
|
||||
pla ; Can always assume at least one bit was set...
|
||||
sta spriteIdx
|
||||
|
||||
pla
|
||||
bmi :out_1
|
||||
sta spriteIdx+2
|
||||
|
||||
pla
|
||||
bmi :out_2
|
||||
sta spriteIdx+4
|
||||
|
||||
pla
|
||||
bmi :out_3
|
||||
sta spriteIdx+6
|
||||
|
||||
; Reset the stack point if we did not pop everything off yet
|
||||
txs
|
||||
|
||||
; These are the exit points which know exactly how many items (x2) have been processed
|
||||
:out_4 lda #8
|
||||
rts
|
||||
:out_0 lda #0
|
||||
rts
|
||||
:out_1 lda #2
|
||||
rts
|
||||
:out_2 lda #4
|
||||
rts
|
||||
:out_3 lda #6
|
||||
rts
|
||||
|
||||
; Fast blit that directly combines a tile with a single sprite and renders directly to the screen
|
||||
;
|
||||
; A = screen address
|
||||
; X = sprite VBUFF address
|
||||
; Y = tile data address
|
||||
FastBlit
|
||||
TILE_DATA_SPAN equ 4
|
||||
|
||||
; If there are two or more sprites at a tile, we can still be fast, but need to do extra work because
|
||||
; the VBUFF values need to be read from the direct page. Thus, the direct page cannot be mapped onto
|
||||
; the graphics screen. We use the stack instead, but have to do extra work to save and restore the
|
||||
; stack value.
|
||||
BlitFourSprites
|
||||
BlitThreeSprites
|
||||
BlitTwoSprites
|
||||
plb
|
||||
tsc
|
||||
sta stkSave ; Save the stack on the direct page
|
||||
|
||||
sei
|
||||
clc
|
||||
|
||||
ldy tileAddr
|
||||
lda screenAddr ; Saved in direct page locations
|
||||
tcs
|
||||
|
||||
_R0W1
|
||||
|
||||
lda tiledata+{0*TILE_DATA_SPAN},y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{0*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{0*SPRITE_PLANE_SPAN},x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{0*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{0*SPRITE_PLANE_SPAN},x
|
||||
sta $00,s
|
||||
|
||||
lda tiledata+{0*TILE_DATA_SPAN}+2,y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{0*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{0*SPRITE_PLANE_SPAN}+2,x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{0*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{0*SPRITE_PLANE_SPAN}+2,x
|
||||
sta $02,s
|
||||
|
||||
lda tiledata+{1*TILE_DATA_SPAN},y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{1*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{1*SPRITE_PLANE_SPAN},x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{1*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{1*SPRITE_PLANE_SPAN},x
|
||||
sta $A0,s
|
||||
|
||||
lda tiledata+{1*TILE_DATA_SPAN}+2,y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{1*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{1*SPRITE_PLANE_SPAN}+2,x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{1*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{1*SPRITE_PLANE_SPAN}+2,x
|
||||
sta $A2,s
|
||||
|
||||
tsc
|
||||
adc #320
|
||||
tcs
|
||||
|
||||
lda tiledata+{2*TILE_DATA_SPAN},y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{2*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{2*SPRITE_PLANE_SPAN},x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{2*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{2*SPRITE_PLANE_SPAN},x
|
||||
sta $00,s
|
||||
|
||||
lda tiledata+{2*TILE_DATA_SPAN}+2,y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{2*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{2*SPRITE_PLANE_SPAN}+2,x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{2*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{2*SPRITE_PLANE_SPAN}+2,x
|
||||
sta $02,s
|
||||
|
||||
lda tiledata+{3*TILE_DATA_SPAN},y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{3*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{3*SPRITE_PLANE_SPAN},x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{3*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{3*SPRITE_PLANE_SPAN},x
|
||||
sta $A0,s
|
||||
|
||||
lda tiledata+{3*TILE_DATA_SPAN}+2,y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{3*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{3*SPRITE_PLANE_SPAN}+2,x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{3*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{3*SPRITE_PLANE_SPAN}+2,x
|
||||
sta $A2,s
|
||||
|
||||
tsc
|
||||
adc #320
|
||||
tcs
|
||||
|
||||
lda tiledata+{4*TILE_DATA_SPAN},y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{4*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{4*SPRITE_PLANE_SPAN},x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{4*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{4*SPRITE_PLANE_SPAN},x
|
||||
sta $00,s
|
||||
|
||||
lda tiledata+{4*TILE_DATA_SPAN}+2,y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{4*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{4*SPRITE_PLANE_SPAN}+2,x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{4*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{4*SPRITE_PLANE_SPAN}+2,x
|
||||
sta $02,s
|
||||
|
||||
lda tiledata+{5*TILE_DATA_SPAN},y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{5*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{5*SPRITE_PLANE_SPAN},x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{5*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{5*SPRITE_PLANE_SPAN},x
|
||||
sta $A0,s
|
||||
|
||||
lda tiledata+{5*TILE_DATA_SPAN}+2,y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{5*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{5*SPRITE_PLANE_SPAN}+2,x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{5*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{5*SPRITE_PLANE_SPAN}+2,x
|
||||
sta $A2,s
|
||||
|
||||
tsc
|
||||
adc #320
|
||||
tcs
|
||||
|
||||
lda tiledata+{6*TILE_DATA_SPAN},y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{6*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{6*SPRITE_PLANE_SPAN},x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{6*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{6*SPRITE_PLANE_SPAN},x
|
||||
sta $00,s
|
||||
|
||||
lda tiledata+{6*TILE_DATA_SPAN}+2,y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{6*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{6*SPRITE_PLANE_SPAN}+2,x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{6*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{6*SPRITE_PLANE_SPAN}+2,x
|
||||
sta $02,s
|
||||
|
||||
lda tiledata+{7*TILE_DATA_SPAN},y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{7*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{7*SPRITE_PLANE_SPAN},x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{7*SPRITE_PLANE_SPAN},x
|
||||
oral spritedata+{7*SPRITE_PLANE_SPAN},x
|
||||
sta $A0,s
|
||||
|
||||
lda tiledata+{7*TILE_DATA_SPAN}+2,y
|
||||
ldx spriteIdx+2
|
||||
andl spritemask+{7*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{7*SPRITE_PLANE_SPAN}+2,x
|
||||
ldx spriteIdx
|
||||
andl spritemask+{7*SPRITE_PLANE_SPAN}+2,x
|
||||
oral spritedata+{7*SPRITE_PLANE_SPAN}+2,x
|
||||
sta $A2,s
|
||||
|
||||
_R0W0
|
||||
|
||||
lda stkSave
|
||||
tcs
|
||||
cli
|
||||
rts
|
||||
|
||||
; There is only one sprite at this tile, so do a fast blit that directly combines a tile with a single
|
||||
; sprite and renders directly to the screen
|
||||
;
|
||||
; NOTE: Expect X-register to already have been set to the correct VBUFF address
|
||||
BlitOneSprite
|
||||
ldy tileAddr ; load the address of this tile's data
|
||||
lda screenAddr ; Get the on-screen address of this tile
|
||||
|
||||
plb
|
||||
|
||||
phd
|
||||
sei
|
||||
clc
|
||||
@ -518,47 +999,3 @@ TILE_DATA_SPAN equ 4
|
||||
cli
|
||||
pld
|
||||
rts
|
||||
|
||||
; Run through all of the active sprites and put then on-screen. We have three different heuristics depending on
|
||||
; how many active sprites there are intersecting this tile.
|
||||
|
||||
; Version 2. No sprite place, instead each sprite has a set of pre-rendered panels and we render from
|
||||
; those panels in tile-sized blocks.
|
||||
;
|
||||
; If there is only one sprite + tile background, then we can render directly to the screen
|
||||
;
|
||||
; ldal tiledata+0,x
|
||||
; and sprite+MASK_OFFSET,y
|
||||
; ora sprite,y
|
||||
; sta 00
|
||||
; ...
|
||||
; sta 02
|
||||
; ...
|
||||
; sta A0
|
||||
; ...
|
||||
; sta A2
|
||||
; tdc
|
||||
; adc #320
|
||||
; tcd
|
||||
;
|
||||
; Since this is a common case, it is reasonable to do so. Otherwise, we must explode the TS_SPRITE_FLAG to
|
||||
; get a list of sprite origin addresses and then flatten against the tile
|
||||
;
|
||||
; ldal tiledata+0,x
|
||||
; ldx spriteCount
|
||||
; jmp (disp,x)
|
||||
; ...
|
||||
; ldy list+2
|
||||
; and sprite+MASK_OFFSET,y
|
||||
; ora sprite,y
|
||||
; ldy list
|
||||
; and sprite+MASK_OFFSET,y
|
||||
; ora sprite,y
|
||||
; sta 00
|
||||
|
||||
; sta 02
|
||||
; sta A0
|
||||
; sta A2
|
||||
; tdc
|
||||
; adc #320
|
||||
; tcd
|
||||
88
src/Sprite.s
88
src/Sprite.s
@ -70,12 +70,9 @@ VBUFF_SPRITE_START equ {8*VBUFF_TILE_ROW_BYTES}+4
|
||||
; the vertical tiles are taken from tileId + 32. This is why tile sheets should be saved
|
||||
; with a width of 256 pixels.
|
||||
;
|
||||
; Single sprite are limited to 24 lines high because there are 28 lines of padding above and below the
|
||||
; sprite plane buffers, so a sprite that is 32 lines high could overflow the drawing area.
|
||||
;
|
||||
; A = tileId + flags
|
||||
; X = x position
|
||||
; Y = y position
|
||||
; Y = High Byte = x-pos, Low Byte = y-pos
|
||||
; X = Sprite Slot (0 - 15)
|
||||
AddSprite ENT
|
||||
phb
|
||||
phk
|
||||
@ -85,15 +82,13 @@ AddSprite ENT
|
||||
rtl
|
||||
|
||||
_AddSprite
|
||||
phx ; Save the horizontal position
|
||||
ldx _NextOpenSlot ; Get the next free sprite slot index
|
||||
bpl :open ; A negative number means we are full
|
||||
pha
|
||||
txa
|
||||
and #$000F
|
||||
asl
|
||||
tax
|
||||
pla
|
||||
|
||||
plx ; Early out
|
||||
sec ; Signal that no sprite slot was available
|
||||
rts
|
||||
|
||||
:open
|
||||
sta _Sprites+SPRITE_ID,x ; Keep a copy of the full descriptor
|
||||
jsr _GetBaseTileAddr ; This applies the TILE_ID_MASK
|
||||
sta _Sprites+TILE_DATA_OFFSET,x
|
||||
@ -101,10 +96,14 @@ _AddSprite
|
||||
lda #SPRITE_STATUS_OCCUPIED+SPRITE_STATUS_ADDED
|
||||
sta _Sprites+SPRITE_STATUS,x
|
||||
|
||||
phy
|
||||
tya
|
||||
and #$00FF
|
||||
sta _Sprites+SPRITE_Y,x ; Y coordinate
|
||||
pla ; X coordinate
|
||||
sta _Sprites+SPRITE_X,x
|
||||
pla
|
||||
xba
|
||||
and #$00FF
|
||||
sta _Sprites+SPRITE_X,x ; X coordinate
|
||||
|
||||
jsr _PrecalcAllSpriteInfo ; Cache sprite property values (simple stuff)
|
||||
jsr _DrawSpriteSheet ; Render the sprite into internal space
|
||||
@ -121,16 +120,6 @@ _AddSprite
|
||||
txa ; And return the sprite ID
|
||||
clc ; Mark that the sprite was successfully added
|
||||
|
||||
; We can only get to this point if there was an open slot, so we know we're not at the
|
||||
; end of the list yet.
|
||||
|
||||
ldx _OpenListHead
|
||||
inx
|
||||
inx
|
||||
stx _OpenListHead
|
||||
ldy _OpenList,x ; If this is the end, then the sentinel value will
|
||||
sty _NextOpenSlot ; get stored into _NextOpenSlot
|
||||
|
||||
rts
|
||||
|
||||
; Run through the list of tile store offsets that this sprite was last drawn into and mark
|
||||
@ -138,79 +127,73 @@ _AddSprite
|
||||
; (an unaligned 4x3 sprite), covering a 5x4 area of play field tiles.
|
||||
;
|
||||
; Y register = sprite record index
|
||||
_CSFTS_Out rts
|
||||
_ClearSpriteFromTileStore
|
||||
ldx _Sprites+TILE_STORE_ADDR_1,y
|
||||
bne *+3
|
||||
rts
|
||||
beq _CSFTS_Out
|
||||
ldal TileStore+TS_SPRITE_FLAG,x ; Clear the bit in the bit field. This seems wasteful, but
|
||||
and _SpriteBitsNot,y ; there is no indexed form of TSB/TRB and caching the value in
|
||||
stal TileStore+TS_SPRITE_FLAG,x ; a direct page location, only saves 1 or 2 cycles per and costs 10.
|
||||
jsr _PushDirtyTileX
|
||||
|
||||
ldx _Sprites+TILE_STORE_ADDR_2,y
|
||||
bne *+3
|
||||
rts
|
||||
beq _CSFTS_Out
|
||||
ldal TileStore+TS_SPRITE_FLAG,x
|
||||
and _SpriteBitsNot,y
|
||||
stal TileStore+TS_SPRITE_FLAG,x
|
||||
jsr _PushDirtyTileX
|
||||
|
||||
ldx _Sprites+TILE_STORE_ADDR_3,y
|
||||
bne *+3
|
||||
rts
|
||||
beq _CSFTS_Out
|
||||
ldal TileStore+TS_SPRITE_FLAG,x
|
||||
and _SpriteBitsNot,y
|
||||
stal TileStore+TS_SPRITE_FLAG,x
|
||||
jsr _PushDirtyTileX
|
||||
|
||||
ldx _Sprites+TILE_STORE_ADDR_4,y
|
||||
bne *+3
|
||||
rts
|
||||
beq _CSFTS_Out
|
||||
ldal TileStore+TS_SPRITE_FLAG,x
|
||||
and _SpriteBitsNot,y
|
||||
stal TileStore+TS_SPRITE_FLAG,x
|
||||
jsr _PushDirtyTileX
|
||||
|
||||
ldx _Sprites+TILE_STORE_ADDR_5,y
|
||||
bne *+3
|
||||
rts
|
||||
beq :out
|
||||
ldal TileStore+TS_SPRITE_FLAG,x
|
||||
and _SpriteBitsNot,y
|
||||
stal TileStore+TS_SPRITE_FLAG,x
|
||||
jsr _PushDirtyTileX
|
||||
|
||||
ldx _Sprites+TILE_STORE_ADDR_6,y
|
||||
bne *+3
|
||||
rts
|
||||
beq :out
|
||||
ldal TileStore+TS_SPRITE_FLAG,x
|
||||
and _SpriteBitsNot,y
|
||||
stal TileStore+TS_SPRITE_FLAG,x
|
||||
jsr _PushDirtyTileX
|
||||
|
||||
ldx _Sprites+TILE_STORE_ADDR_7,y
|
||||
bne *+3
|
||||
rts
|
||||
beq :out
|
||||
ldal TileStore+TS_SPRITE_FLAG,x
|
||||
and _SpriteBitsNot,y
|
||||
stal TileStore+TS_SPRITE_FLAG,x
|
||||
jsr _PushDirtyTileX
|
||||
|
||||
ldx _Sprites+TILE_STORE_ADDR_8,y
|
||||
bne *+3
|
||||
rts
|
||||
beq :out
|
||||
ldal TileStore+TS_SPRITE_FLAG,x
|
||||
and _SpriteBitsNot,y
|
||||
stal TileStore+TS_SPRITE_FLAG,x
|
||||
jsr _PushDirtyTileX
|
||||
|
||||
ldx _Sprites+TILE_STORE_ADDR_9,y
|
||||
bne *+3
|
||||
rts
|
||||
beq :out
|
||||
ldal TileStore+TS_SPRITE_FLAG,x
|
||||
and _SpriteBitsNot,y
|
||||
stal TileStore+TS_SPRITE_FLAG,x
|
||||
jmp _PushDirtyTileX
|
||||
|
||||
:out rts
|
||||
|
||||
; This function looks at the sprite list and renders the sprite plane data into the appropriate
|
||||
; tiles in the code field. There are a few phases to this routine. The assumption is that
|
||||
; any sprite that needs to be re-drawn has been marked as DIRTY or DAMAGED.
|
||||
@ -300,8 +283,7 @@ _DoPhase1
|
||||
jsr _ClearSpriteFromTileStore
|
||||
:no_clear
|
||||
|
||||
; Check to see if sprite was REMOVED If so, then this is where we return its Sprite ID to the
|
||||
; list of open slots
|
||||
; Check to see if sprite was REMOVED If so, clear the sprite slot status
|
||||
|
||||
lda _Sprites+SPRITE_STATUS,y
|
||||
bit #SPRITE_STATUS_REMOVED
|
||||
@ -313,13 +295,6 @@ _DoPhase1
|
||||
lda _SpriteBits,y ; Clear from the sprite bitmap
|
||||
trb SpriteMap
|
||||
|
||||
ldx _OpenListHead
|
||||
dex
|
||||
dex
|
||||
stx _OpenListHead
|
||||
tya
|
||||
sta _OpenList,x
|
||||
sty _NextOpenSlot
|
||||
:out
|
||||
rts
|
||||
|
||||
@ -390,6 +365,7 @@ _DoPhase2
|
||||
beq :out
|
||||
|
||||
; Last thing to do, so go ahead and clear the flags
|
||||
|
||||
lda #SPRITE_STATUS_OCCUPIED
|
||||
sta _Sprites+SPRITE_STATUS,y
|
||||
|
||||
@ -494,8 +470,6 @@ phase1_rtn
|
||||
jmp (phase2,x)
|
||||
phase2_rtn
|
||||
|
||||
; Sprite rendering complete, clear the dirty bits
|
||||
|
||||
rts
|
||||
|
||||
; _GetTileAt
|
||||
@ -849,10 +823,4 @@ SPRITE_HEIGHT equ {MAX_SPRITES*46}
|
||||
SPRITE_CLIP_WIDTH equ {MAX_SPRITES*48}
|
||||
SPRITE_CLIP_HEIGHT equ {MAX_SPRITES*50}
|
||||
|
||||
; Maintain the index of the next open sprite slot. This allows us to have amortized
|
||||
; constant sprite add performance. A negative value means no slots are available.
|
||||
_NextOpenSlot dw 0
|
||||
_OpenListHead dw 0
|
||||
_OpenList dw 0,2,4,6,8,10,12,14,16,18,20,22,24,26,28,30,$FFFF ; List with sentinel at the end
|
||||
|
||||
_Sprites ds SPRITE_REC_SIZE*MAX_SPRITES
|
||||
|
||||
@ -330,7 +330,6 @@ _MarkDirtySprite
|
||||
|
||||
lda VBuffOrigin
|
||||
sta [tmp0],y
|
||||
stal TileStore+TS_LAST_VBUFF,x
|
||||
|
||||
; lda VBuffOrigin ; This is an interesting case. The mapping between the tile store
|
||||
; adc #{0*4}+{0*256} ; and the sprite buffers changes as the StartX, StartY values change
|
||||
@ -362,7 +361,6 @@ _MarkDirtySprite
|
||||
lda VBuffOrigin
|
||||
adc #{0*4}+{1*8*SPRITE_PLANE_SPAN}
|
||||
sta [tmp0],y
|
||||
stal TileStore+TS_LAST_VBUFF,x
|
||||
|
||||
lda SpriteBit
|
||||
oral TileStore+TS_SPRITE_FLAG,x
|
||||
@ -383,7 +381,6 @@ _MarkDirtySprite
|
||||
lda VBuffOrigin
|
||||
adc #{0*4}+{2*8*SPRITE_PLANE_SPAN}
|
||||
sta [tmp0],y
|
||||
stal TileStore+TS_LAST_VBUFF,x
|
||||
|
||||
lda SpriteBit
|
||||
oral TileStore+TS_SPRITE_FLAG,x
|
||||
@ -405,7 +402,6 @@ _MarkDirtySprite
|
||||
lda VBuffOrigin
|
||||
adc #{1*4}+{0*8*SPRITE_PLANE_SPAN}
|
||||
sta [tmp0],y
|
||||
stal TileStore+TS_LAST_VBUFF,x
|
||||
|
||||
lda SpriteBit
|
||||
oral TileStore+TS_SPRITE_FLAG,x
|
||||
@ -427,7 +423,6 @@ _MarkDirtySprite
|
||||
lda VBuffOrigin
|
||||
adc #{1*4}+{1*8*SPRITE_PLANE_SPAN}
|
||||
sta [tmp0],y
|
||||
stal TileStore+TS_LAST_VBUFF,x
|
||||
|
||||
lda SpriteBit
|
||||
oral TileStore+TS_SPRITE_FLAG,x
|
||||
@ -449,7 +444,6 @@ _MarkDirtySprite
|
||||
lda VBuffOrigin
|
||||
adc #{1*4}+{2*8*SPRITE_PLANE_SPAN}
|
||||
sta [tmp0],y
|
||||
stal TileStore+TS_LAST_VBUFF,x
|
||||
|
||||
lda SpriteBit
|
||||
oral TileStore+TS_SPRITE_FLAG,x
|
||||
@ -471,7 +465,6 @@ _MarkDirtySprite
|
||||
lda VBuffOrigin
|
||||
adc #{2*4}+{0*8*SPRITE_PLANE_SPAN}
|
||||
sta [tmp0],y
|
||||
stal TileStore+TS_LAST_VBUFF,x
|
||||
|
||||
lda SpriteBit
|
||||
oral TileStore+TS_SPRITE_FLAG,x
|
||||
@ -493,7 +486,6 @@ _MarkDirtySprite
|
||||
lda VBuffOrigin
|
||||
adc #{2*4}+{1*8*SPRITE_PLANE_SPAN}
|
||||
sta [tmp0],y
|
||||
stal TileStore+TS_LAST_VBUFF,x
|
||||
|
||||
lda SpriteBit
|
||||
oral TileStore+TS_SPRITE_FLAG,x
|
||||
@ -515,7 +507,6 @@ _MarkDirtySprite
|
||||
lda VBuffOrigin
|
||||
adc #{2*4}+{2*8*SPRITE_PLANE_SPAN}
|
||||
sta [tmp0],y
|
||||
stal TileStore+TS_LAST_VBUFF,x
|
||||
|
||||
lda SpriteBit
|
||||
oral TileStore+TS_SPRITE_FLAG,x
|
||||
|
||||
@ -124,8 +124,8 @@ _RenderTile2
|
||||
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
|
||||
|
||||
txa
|
||||
jsr BuildActiveSpriteArray ; Build the max 4 array of active sprites for this tile
|
||||
; txa
|
||||
; jsr BuildActiveSpriteArray ; Build the max 4 array of active sprites for this tile
|
||||
; sta ActiveSpriteCount
|
||||
|
||||
lda TileStore+TS_VBUFF_ARRAY_ADDR,y ; Scratch space
|
||||
@ -591,7 +591,6 @@ InitTiles
|
||||
stal TileStore+TS_TILE_ID,x ; clear the tile store with the special zero tile
|
||||
stal TileStore+TS_TILE_ADDR,x
|
||||
stal TileStore+TS_TILE_DISP,x
|
||||
stal TileStore+TS_LAST_VBUFF,x
|
||||
|
||||
stal TileStore+TS_SPRITE_FLAG,x ; no sprites are set at the beginning
|
||||
lda #$FFFF ; none of the tiles are dirty
|
||||
@ -737,11 +736,11 @@ _PushDirtyTileX
|
||||
txa ; any non-negative value will work, this saves work below
|
||||
stal TileStore+TS_DIRTY,x ; and is 1 cycle faster than loading a constant value
|
||||
|
||||
ldx DirtyTileCount ; 5
|
||||
sta DirtyTiles,x ; 5
|
||||
inx
|
||||
inx
|
||||
stx DirtyTileCount
|
||||
ldx DirtyTileCount ; 4
|
||||
sta DirtyTiles,x ; 6
|
||||
inx ; 2
|
||||
inx ; 2
|
||||
stx DirtyTileCount ; 4 = 18
|
||||
rts
|
||||
:occupied2
|
||||
txa ; Make sure TileStore offset is returned in the accumulator
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user