mirror of
https://github.com/sehugg/8bitworkshop.git
synced 2025-02-18 00:30:43 +00:00
started on VCS library
This commit is contained in:
Steven Hugg
parent
8581fcabd6
commit
61d7860e12
@ -54,6 +54,8 @@ TODO:
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- better VCS single stepping, maybe also listings
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- better VCS single stepping, maybe also listings
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- New File (include file)
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- New File (include file)
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- VCS skips step on lsr/lsr after run to line
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- VCS skips step on lsr/lsr after run to line
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- update window list after building 2nd time?
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- stop debugging where mouse clicked
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FYI: Image links for the books on http://8bitworkshop.com/ are broken
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FYI: Image links for the books on http://8bitworkshop.com/ are broken
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On the website the additional grey spacing next to the program line numbers is not dynamically resized when the web browser window size is changed. Intentional?
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On the website the additional grey spacing next to the program line numbers is not dynamically resized when the web browser window size is changed. Intentional?
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144
presets/vcs/6digit.inc
Normal file
144
presets/vcs/6digit.inc
Normal file
@ -0,0 +1,144 @@
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seg.u Variables
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; Pointers to bitmap for each digit
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Digit0 .word
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Digit1 .word
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Digit2 .word
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Digit3 .word
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Digit4 .word
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Digit5 .word
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BCDScore hex 000000
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THREE_COPIES equ %011 ; for NUSIZ registers
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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seg Code
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; setup 6-digit score
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Digit6Setup: subroutine
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lda #$18
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sta COLUP0
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lda #$28
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sta COLUP1
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lda #THREE_COPIES
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sta NUSIZ0
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sta NUSIZ1
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; set horizontal position of player objects
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sta WSYNC
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SLEEP 26
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sta RESP0
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sta RESP1
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lda #$10
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sta HMP1
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sta WSYNC
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sta HMOVE
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sta HMCLR
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lda #0
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sta REFP0
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sta REFP1
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sta GRP0
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sta GRP1
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lda #1
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sta VDELP0
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sta VDELP1
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rts
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; Adds value to 6-BCD-digit score.
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; A = 1st BCD digit
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; X = 2nd BCD digit
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; Y = 3rd BCD digit
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AddScore: subroutine
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.temp equ Temp1
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sed ; enter BCD mode
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clc ; clear carry
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sta .temp
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lda BCDScore
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adc .temp
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sta BCDScore
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stx .temp
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lda BCDScore+1
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adc .temp
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sta BCDScore+1
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sty .temp
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lda BCDScore+2
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adc .temp
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sta BCDScore+2
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cld ; exit BCD mode
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rts
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GetDigitPtrs: subroutine
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ldx #0 ; leftmost bitmap
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ldy #2 ; start from most-sigificant BCD value
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.Loop
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lda BCDScore,y ; get BCD value
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and #$f0 ; isolate high nibble (* 16)
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lsr ; shift right 1 bit (* 8)
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sta Digit0,x ; store pointer lo byte
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lda #>Digit6Font
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sta Digit0+1,x ; store pointer hi byte
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inx
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inx ; next bitmap pointer
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lda BCDScore,y ; get BCD value (again)
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and #$f ; isolate low nibble
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asl
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asl
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asl ; * 8
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sta Digit0,x ; store pointer lo byte
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lda #>Digit6Font
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sta Digit0+1,x ; store pointer hi byte
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inx
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inx ; next bitmap pointer
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dey ; next BCD value
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bpl .Loop ; repeat until < 0
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rts
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; Display the resulting 48x8 bitmap
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; using the Digit0-5 pointers.
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DrawDigits: subroutine
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.temp equ Temp1
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.count equ Temp2
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sta WSYNC
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SLEEP 40 ; start near end of scanline
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lda #7
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sta .count
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.bigloop
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ldy .count ; counts backwards
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lda (Digit0),y ; load B0 (1st sprite byte)
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sta GRP0 ; B0 -> [GRP0]
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lda (Digit1),y ; load B1 -> A
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sta GRP1 ; B1 -> [GRP1], B0 -> GRP0
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sta WSYNC ; sync to next scanline
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lda (Digit2),y ; load B2 -> A
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sta GRP0 ; B2 -> [GRP0], B1 -> GRP1
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lda (Digit5),y ; load B5 -> A
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sta .temp ; B5 -> temp
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lda (Digit4),y ; load B4
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tax ; -> X
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lda (Digit3),y ; load B3 -> A
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ldy .temp ; load B5 -> Y
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sta GRP1 ; B3 -> [GRP1]; B2 -> GRP0
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stx GRP0 ; B4 -> [GRP0]; B3 -> GRP1
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sty GRP1 ; B5 -> [GRP1]; B4 -> GRP0
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sta GRP0 ; ?? -> [GRP0]; B5 -> GRP1
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dec .count ; go to next line
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bpl .bigloop ; repeat until < 0
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lda #0 ; clear the sprite registers
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sta GRP0
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sta GRP1
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sta GRP0
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sta GRP1
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rts
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; Font table for digits 0-9 (8x8 pixels)
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align $100 ; make sure data doesn't cross page boundary
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Digit6Font:
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hex 003c6666766e663c007e181818381818
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hex 007e60300c06663c003c66061c06663c
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hex 0006067f661e0e06003c6606067c607e
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hex 003c66667c60663c00181818180c667e
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hex 003c66663c66663c003c66063e66663c
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257
presets/vcs/examples/testlibrary.a
Normal file
257
presets/vcs/examples/testlibrary.a
Normal file
@ -0,0 +1,257 @@
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processor 6502
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include "vcs.h"
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include "macro.h"
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include "xmacro.h"
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include "xtimer.h"
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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seg.u Variables
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org $80
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Temp1 .byte
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Temp2 .byte
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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seg Code
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org $f000
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jmp Start
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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include "setpos.inc" ; SetHorizPos routine
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include "xtimer.inc" ; WaitForScanline routine and lookup table
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include "multisprite.inc" ; multi 2-player color 2-line kernel w/ background
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include "6digit.inc" ; 6-digit scoreboard
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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; Initialize and set initial X and Y offsets of objects.
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Start
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CLEAN_START
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jsr MSpriteInit
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ldx #0
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lda #MinYPos
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ldy #40
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InitLoop
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sty XPos0,x
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sta YPos0,x
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sta Flags0,x
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clc
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adc #13
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iny
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iny
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iny
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iny
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iny
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iny
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inx
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cpx #NSprites
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bne InitLoop
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lda #0
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sta Shape0
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lda #1
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sta Shape0+1
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lda #2
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sta Shape0+2
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sta Shape0+4
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sta Shape0+6
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lda #3
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sta Shape0+3
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sta Shape0+5
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sta Shape0+7
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lda #>Start
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sta PF0Ptr+1
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lda #>Start+1
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sta PF1Ptr+1
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lda #>Start+1
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sta PF2Ptr+1
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; Next frame loop
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NextFrame
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VERTICAL_SYNC
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TIMER_SETUP 37
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; Do joystick movement
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ldy #1
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jsr MoveJoystick
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jsr Digit6Setup
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jsr GetDigitPtrs
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jsr MSpritePre
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TIMER_WAIT
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; end of VBLANK
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TIMER_TABLE_SETUP
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; Scoreboard
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jsr DrawDigits
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; Scanline loop
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lda #$90
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sta COLUBK
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lda #22
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jsr MSpriteDraw2
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; Overscan
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TIMER_SETUP 28
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; Clear all colors to black before overscan
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ldx #0
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stx COLUBK
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stx COLUP0
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stx COLUP1
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stx COLUPF
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; 30-2 lines of overscan
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TIMER_WAIT
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; Go to next frame
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jmp NextFrame
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; Read joystick movement and apply to object 0
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MoveJoystick subroutine
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; Move vertically
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ldx YPos0,y
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lda #%00010000 ;Up?
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bit SWCHA
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bne .SkipMoveUp
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cpx #MinYPos+1
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bcc .SkipMoveUp
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dex
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.SkipMoveUp
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lda #%00100000 ;Down?
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bit SWCHA
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bne .SkipMoveDown
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cpx #180
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bcs .SkipMoveDown
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inx
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.SkipMoveDown
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stx YPos0,y
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; Move horizontally
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ldx XPos0,y
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lda #%01000000 ;Left?
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bit SWCHA
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bne .SkipMoveLeft
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cpx #5
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bcc .SkipMoveLeft
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dex
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lda #$08
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sta Flags0,y
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.SkipMoveLeft
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lda #%10000000 ;Right?
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bit SWCHA
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bne .SkipMoveRight
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cpx #160
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bcs .SkipMoveRight
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inx
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lda #$00
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sta Flags0,y
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.SkipMoveRight
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stx XPos0,y
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rts
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; TODO: do we need trailing padding?
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; Bitmap data "standing" position
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Frame0
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.byte #0
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.byte #%01101100;$F6
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.byte #%00101000;$86
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.byte #%00101000;$86
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.byte #%00111000;$86
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.byte #%10111010;$C2
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.byte #%10111010;$C2
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.byte #%01111100;$C2
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.byte #%00111000;$C2
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.byte #%00111000;$16
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.byte #%01000100;$16
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.byte #%01111100;$16
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.byte #%01111100;$18
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.byte #%01010100;$18
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.byte #%01111100;$18
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.byte #%11111110;$F2
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.byte #%00111000;$F4
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; Bitmap data "throwing" position
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Frame1
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.byte #0
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.byte #%01101100;$F6
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.byte #%01000100;$86
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.byte #%00101000;$86
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.byte #%00111000;$86
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.byte #%10111010;$C2
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.byte #%10111101;$C2
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.byte #%01111101;$C2
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.byte #%00111001;$C2
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.byte #%00111000;$16
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.byte #%01101100;$16
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.byte #%01111100;$16
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.byte #%01111100;$18
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.byte #%01010100;$18
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.byte #%01111100;$18
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.byte #%11111110;$F2
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.byte #%00111000;$F4
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; Color data for each line of sprite
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ColorFrame0
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.byte #16 ; height
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.byte #$F6;
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.byte #$86;
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.byte #$86;
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.byte #$86;
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.byte #$C2;
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.byte #$C2;
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.byte #$C2;
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.byte #$C2;
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.byte #$16;
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.byte #$16;
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.byte #$16;
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.byte #$18;
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.byte #$18;
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.byte #$18;
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||||||
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.byte #$F2;
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.byte #$F4;
|
||||||
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||||||
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; Enemy cat-head graphics data
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EnemyFrame0
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.byte #0
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.byte #%00111100;$AE
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||||||
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.byte #%01000010;$AE
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||||||
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.byte #%11100111;$AE
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||||||
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.byte #%11111111;$AC
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||||||
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.byte #%10011001;$8E
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||||||
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.byte #%01111110;$8E
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||||||
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.byte #%11000011;$98
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||||||
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.byte #%10000001;$98
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||||||
|
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||||||
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; Enemy cat-head color data
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||||||
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EnemyColorFrame0
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||||||
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.byte #8 ; height
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||||||
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.byte #$AE;
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||||||
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.byte #$AC;
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||||||
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.byte #$A8;
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.byte #$AC;
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.byte #$8E;
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.byte #$8E;
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||||||
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.byte #$98;
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||||||
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.byte #$94;
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||||||
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||||||
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; Enemy cat-head color data
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EnemyColorFrame1
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.byte #8 ; height
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.byte #$FE;
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.byte #$FC;
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.byte #$28;
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.byte #$2C;
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.byte #$EE;
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.byte #$EE;
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.byte #$D8;
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.byte #$D4;
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||||||
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||||||
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; Mapping of sprite shapes to sprite data
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SpriteDataMap
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.word Frame0,ColorFrame0
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||||||
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.word Frame1,ColorFrame0
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.word EnemyFrame0,EnemyColorFrame0
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.word EnemyFrame0,EnemyColorFrame1
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; Epilogue
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org $fffc
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.word Start
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.word Start
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||||||
1
presets/vcs/km2pc2sb.inc
Normal file
1
presets/vcs/km2pc2sb.inc
Normal file
@ -0,0 +1 @@
|
|||||||
|
|
||||||
537
presets/vcs/multisprite.inc
Normal file
537
presets/vcs/multisprite.inc
Normal file
@ -0,0 +1,537 @@
|
|||||||
|
|
||||||
|
|
||||||
|
; MULTISPRITE LIBRARY
|
||||||
|
|
||||||
|
; For lots of games, we'd like to display more than two sprites.
|
||||||
|
; There are lots of different ways to tackle this on the VCS,
|
||||||
|
; but we're going to try for a generalized approach that lets
|
||||||
|
; use have N different sprites at any X-Y coordinate, each with
|
||||||
|
; its own bitmap and color table. This is tricky because we can
|
||||||
|
; only do so much on each scanline.
|
||||||
|
|
||||||
|
; Our approach is to separate the problem into three phases.
|
||||||
|
; In the sort phase, we sort all sprites by Y coordinate.
|
||||||
|
; We do one sort pass per frame, so it may take several frames
|
||||||
|
; for the sort to stabilize.
|
||||||
|
; In the positioning phase, we look at the sprites in Y-sorted
|
||||||
|
; order, looking several lines ahead to see if a sprite is
|
||||||
|
; coming up. We then allocate it to one of the two player
|
||||||
|
; objects in hardware and set its position using the SetHorizPos
|
||||||
|
; method. We can set one or both of the player objects this way.
|
||||||
|
|
||||||
|
; In the display phase, we display the objects which we previously
|
||||||
|
; assigned and positioned. First we figure out how many scanlines are
|
||||||
|
; required. If only one object is scheduled, we just use its height.
|
||||||
|
; If two objects are scheduled, we go until the bottommost line has
|
||||||
|
; been displayed. We then loop through, fetching pixels and colors
|
||||||
|
; for one or both objects (up to four lookup tables) and setting
|
||||||
|
; registers at the appropriate time. We don't have time to do much
|
||||||
|
; else, so we don't look for any new objects to schedule until
|
||||||
|
; we're done with this loop.
|
||||||
|
|
||||||
|
; This scheme can only display up to two objects on a given
|
||||||
|
; scanline, so if the system tries to schedule a third, it will
|
||||||
|
; be ignored. Also, the positioning routine takes a few scanlines
|
||||||
|
; to complete, so if the top of a sprite is too close to the
|
||||||
|
; bottom of another sprite, the latter may not be displayed.
|
||||||
|
;
|
||||||
|
; To mitigate this, we increment a priority counter when a
|
||||||
|
; sprite entry is missed. In the sort phase, we move those sprites
|
||||||
|
; ahead of lower priority sprites in the sort order. This makes
|
||||||
|
; overlapping sprites flicker instead of randomly disappear.
|
||||||
|
|
||||||
|
; There are two separate multisprite kernels:
|
||||||
|
|
||||||
|
; MSpriteDraw1 - Single-line sprites, no playfield.
|
||||||
|
; This kernel requires TIMER_TABLE_SETUP at the 0th
|
||||||
|
; scanline, as it uses the timer to figure out the
|
||||||
|
; current scanline.
|
||||||
|
|
||||||
|
; MSpriteDraw2 - Double-line sprites with playfield.
|
||||||
|
; The playfield is updated and the sprites are positioned
|
||||||
|
; in 8-scanline segments.
|
||||||
|
; This kernel uses the timer internally, but does not
|
||||||
|
; use the timer table or TIMER_TABLE_SETUP.
|
||||||
|
|
||||||
|
; Your program must call MSpriteInit when it starts,
|
||||||
|
; and MSpritePre between every frame.
|
||||||
|
|
||||||
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
||||||
|
|
||||||
|
seg.u Variables
|
||||||
|
|
||||||
|
Scanline byte ; current scanline
|
||||||
|
CurIndex byte ; current sprite # to try to schedule
|
||||||
|
|
||||||
|
PData0 word ; pointer (lo/hi) to player 0 bitmap data
|
||||||
|
PData1 word ; pointer to player 1 bitmap data
|
||||||
|
PColr0 word ; pointer to player 0 color data
|
||||||
|
PColr1 word ; pointer to player 1 color data
|
||||||
|
SIndx0 byte ; next y-position to draw player 0
|
||||||
|
; or during draw, index into sprite
|
||||||
|
; zero means not assigned
|
||||||
|
SIndx1 byte ; ... for player 1
|
||||||
|
SSize0 byte ; sprite size for player 0
|
||||||
|
SSize1 byte ; sprite size for player 1
|
||||||
|
|
||||||
|
NSprites equ 8 ; max # of sprites
|
||||||
|
XPos0 ds NSprites ; x coord for each sprite
|
||||||
|
YPos0 ds NSprites ; y coord for each sprite
|
||||||
|
Shape0 ds NSprites ; shape index
|
||||||
|
Flags0 ds NSprites ; NUSIZ and reflection flags
|
||||||
|
Sorted0 ds NSprites ; sorted list of sprite indices
|
||||||
|
Priority0 ds NSprites ; sprite priority list, if missed
|
||||||
|
|
||||||
|
;MinYDist equ 0 ; min. Y distance to consider sprite (not used)
|
||||||
|
;MinYPos equ 1 ; TODO???
|
||||||
|
MinYDist equ 6 ; min. Y distance to consider sprite
|
||||||
|
MinYPos equ 2+MinYDist
|
||||||
|
|
||||||
|
PF0Ptr word ; pointer to playfield data
|
||||||
|
PF1Ptr word ; pointer to playfield data
|
||||||
|
PF2Ptr word ; pointer to playfield data
|
||||||
|
PFIndex byte ; offset into playfield array
|
||||||
|
PFCount byte ; lines left in this playfield segment
|
||||||
|
|
||||||
|
; temporary values for kernel
|
||||||
|
; TODO: share with global temporaries
|
||||||
|
Temp byte
|
||||||
|
Colp0 byte
|
||||||
|
Colp1 byte
|
||||||
|
tmpPF0 byte
|
||||||
|
tmpPF1 byte
|
||||||
|
tmpPF2 byte
|
||||||
|
|
||||||
|
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
||||||
|
|
||||||
|
seg Code
|
||||||
|
|
||||||
|
; call at start of program
|
||||||
|
MSpriteInit subroutine
|
||||||
|
; Initialize initial sort order
|
||||||
|
ldx #0
|
||||||
|
.loop
|
||||||
|
txa
|
||||||
|
sta Sorted0,x
|
||||||
|
inx
|
||||||
|
cpx #NSprites
|
||||||
|
bne .loop
|
||||||
|
rts
|
||||||
|
|
||||||
|
; call between frames
|
||||||
|
MSpritePre subroutine
|
||||||
|
; Do one iteration of bubble sort on sprite indices
|
||||||
|
ldx #NSprites-2
|
||||||
|
.SortLoop
|
||||||
|
jsr SwapSprites
|
||||||
|
dex
|
||||||
|
bpl .SortLoop ; loop until <= 0
|
||||||
|
; Reset scanline counter and sprite objects
|
||||||
|
ldx #0
|
||||||
|
stx CurIndex
|
||||||
|
stx SIndx0
|
||||||
|
stx SIndx1
|
||||||
|
stx SSize0
|
||||||
|
stx SSize1
|
||||||
|
rts
|
||||||
|
|
||||||
|
; single-line kernel routine
|
||||||
|
MSpriteDraw1 subroutine
|
||||||
|
.NextFindSprite
|
||||||
|
; Try to schedule sprites to both players
|
||||||
|
jsr FindAnotherSprite
|
||||||
|
jsr FindAnotherSprite
|
||||||
|
; Apply fine offsets
|
||||||
|
sta WSYNC ; start next scanline
|
||||||
|
sta HMOVE ; apply the previous fine position(s)
|
||||||
|
sta HMCLR ; clear motion registers
|
||||||
|
ldx #0
|
||||||
|
stx VDELP0 ; set vertical delay off
|
||||||
|
stx VDELP1 ; set vertical delay off
|
||||||
|
; See if time to draw
|
||||||
|
jsr DrawSprites1
|
||||||
|
; Repeat until all scanlines drawn
|
||||||
|
lda INTIM
|
||||||
|
cmp #$1f
|
||||||
|
bcs .NextFindSprite
|
||||||
|
lda #191
|
||||||
|
jmp WaitForScanline
|
||||||
|
|
||||||
|
; called by single-line kernel
|
||||||
|
DrawSprites1 subroutine
|
||||||
|
; Wait for next precise scanline
|
||||||
|
lda #0 ; 0 = wait for next
|
||||||
|
.AnotherScanline
|
||||||
|
jsr WaitForScanline
|
||||||
|
lda Timer2Scanline,y ; lookup scanline #
|
||||||
|
beq .AnotherScanline ; not if zero!
|
||||||
|
sta Scanline ; save it
|
||||||
|
; Calculate # of lines to draw for each sprite
|
||||||
|
; Sprite Y - current scanline + sprite height
|
||||||
|
lda SIndx0
|
||||||
|
beq .Empty0 ; sprite 0 is inactive?
|
||||||
|
sec
|
||||||
|
sbc Scanline
|
||||||
|
clc
|
||||||
|
adc SSize0
|
||||||
|
sta SIndx0 ; SIndx0 += SSize0 - Scanline
|
||||||
|
.Empty0
|
||||||
|
lda SIndx1
|
||||||
|
beq .Empty1 ; sprite 1 is inactive?
|
||||||
|
sec
|
||||||
|
sbc Scanline
|
||||||
|
clc
|
||||||
|
adc SSize1
|
||||||
|
sta SIndx1 ; SIndx1 += SSize1 - Scanline
|
||||||
|
.Empty1
|
||||||
|
; Find out the maximum # of lines to draw
|
||||||
|
; by taking the maximum of the two sprite heights
|
||||||
|
cmp SIndx0
|
||||||
|
bpl .Cmp1 ; sindx0 < sindx1?
|
||||||
|
lda SIndx0
|
||||||
|
.Cmp1
|
||||||
|
tax ; X = # of lines left to draw
|
||||||
|
beq .NoSprites ; X = 0? we're done
|
||||||
|
sta WSYNC ; next scanline
|
||||||
|
.DrawNextScanline
|
||||||
|
; Make sure player 0 index is within bounds
|
||||||
|
ldy SIndx0
|
||||||
|
cpy SSize0
|
||||||
|
bcs .Inactive0 ; index >= size? (or index < 0)
|
||||||
|
; Lookup pixels for player 0
|
||||||
|
lda (PData0),y
|
||||||
|
; Do WSYNC and then quickly store pixels for player 0
|
||||||
|
sta WSYNC
|
||||||
|
sta GRP0
|
||||||
|
; Lookup/store colors for player 0
|
||||||
|
lda (PColr0),y
|
||||||
|
sta COLUP0
|
||||||
|
.DrawSprite1
|
||||||
|
; Make sure player 1 index is within bounds
|
||||||
|
ldy SIndx1
|
||||||
|
cpy SSize1
|
||||||
|
bcs .Inactive1 ; index >= size? (or index < 0)
|
||||||
|
; Lookup/store pixels and colors for player 1
|
||||||
|
; Note that we are already 30-40 pixels into the scanline
|
||||||
|
; by this point...
|
||||||
|
lda (PData1),y
|
||||||
|
sta GRP1
|
||||||
|
lda (PColr1),y
|
||||||
|
sta COLUP1
|
||||||
|
.Inactive1
|
||||||
|
; Decrement the two sprite indices
|
||||||
|
dey
|
||||||
|
sty SIndx1
|
||||||
|
dec SIndx0
|
||||||
|
; Repeat until we've drawn all the scanlines for this job
|
||||||
|
dex
|
||||||
|
bne .DrawNextScanline
|
||||||
|
; Free up both player objects by zeroing them out
|
||||||
|
stx SIndx0
|
||||||
|
stx SIndx1
|
||||||
|
stx SSize0
|
||||||
|
stx SSize1
|
||||||
|
sta WSYNC
|
||||||
|
stx GRP0
|
||||||
|
stx GRP1
|
||||||
|
; No sprites were drawn; just exit
|
||||||
|
.NoSprites
|
||||||
|
rts
|
||||||
|
.Inactive0
|
||||||
|
; Alternate player 0 path when it is inactive
|
||||||
|
sta WSYNC
|
||||||
|
lda #0
|
||||||
|
sta GRP0
|
||||||
|
sta COLUP0
|
||||||
|
beq .DrawSprite1 ; always taken due to lda #0
|
||||||
|
|
||||||
|
MSpriteDraw2 subroutine
|
||||||
|
sta WSYNC
|
||||||
|
sta PFIndex ; 24 * 4 scanlines = 96 2xlines
|
||||||
|
lda #0
|
||||||
|
sta PFCount
|
||||||
|
sta VDELP1
|
||||||
|
lda #1
|
||||||
|
sta VDELP0 ; updates to GRP0 will be delayed
|
||||||
|
.KernelLoop
|
||||||
|
dec PFCount
|
||||||
|
bmi .NewSprites
|
||||||
|
.Draw8Lines
|
||||||
|
; Phase 0: Fetch PF0 byte
|
||||||
|
jsr DrawSprites2
|
||||||
|
ldy PFIndex
|
||||||
|
lda (PF0Ptr),y ; load PF0
|
||||||
|
sta tmpPF0
|
||||||
|
; Phase 1: Fetch PF1 byte
|
||||||
|
jsr DrawSprites2
|
||||||
|
ldy PFIndex
|
||||||
|
lda (PF1Ptr),y ; load PF1
|
||||||
|
sta tmpPF1
|
||||||
|
; Phase 2: Fetch PF2 byte
|
||||||
|
jsr DrawSprites2
|
||||||
|
ldy PFIndex
|
||||||
|
lda (PF2Ptr),y ; load PF2
|
||||||
|
sty PFIndex
|
||||||
|
sta tmpPF2
|
||||||
|
; Phase 3: Write PF0/PF1/PF2 registers
|
||||||
|
jsr DrawSprites2
|
||||||
|
lda tmpPF0
|
||||||
|
sta PF0
|
||||||
|
lda tmpPF1
|
||||||
|
sta PF1
|
||||||
|
lda tmpPF2
|
||||||
|
sta PF2
|
||||||
|
; Go to next scanline, unless playfield is done
|
||||||
|
dec PFIndex
|
||||||
|
bpl .KernelLoop
|
||||||
|
.NoMoreLines
|
||||||
|
rts
|
||||||
|
.NewSprites
|
||||||
|
; lda PFIndex
|
||||||
|
; sta COLUBK
|
||||||
|
lda PFIndex
|
||||||
|
asl
|
||||||
|
asl
|
||||||
|
eor #$7f
|
||||||
|
sbc #34
|
||||||
|
sta Scanline ; Scanlines = 127 - PFIndex*4
|
||||||
|
; Set up 0-2 player objects taking up to 8 scanlines
|
||||||
|
TIMER_SETUP 8
|
||||||
|
ldx #0
|
||||||
|
stx SSize0
|
||||||
|
stx SSize1
|
||||||
|
stx SIndx0
|
||||||
|
stx SIndx1
|
||||||
|
jsr FindAnotherSprite2
|
||||||
|
; jsr FindAnotherSprite2
|
||||||
|
jsr CalcSpriteEnd
|
||||||
|
; Update playfield
|
||||||
|
ldy PFIndex
|
||||||
|
lda (PF0Ptr),y ; load PF0 -> X
|
||||||
|
tax
|
||||||
|
lda (PF1Ptr),y ; load PF1 -> tmp
|
||||||
|
sta tmpPF1
|
||||||
|
lda (PF2Ptr),y ; load PF2 -> Y
|
||||||
|
tay
|
||||||
|
; Apply fine offsets
|
||||||
|
TIMER_WAIT ; wait for 8th scanlines and WSYNC
|
||||||
|
sta HMOVE ; apply the previous fine position(s)
|
||||||
|
sta HMCLR ; clear motion registers
|
||||||
|
; Store playfield registers
|
||||||
|
stx PF0
|
||||||
|
lda tmpPF1
|
||||||
|
sta PF1
|
||||||
|
sty PF2
|
||||||
|
dec PFIndex ; no more playfield?
|
||||||
|
bpl .KernelLoop
|
||||||
|
jmp .NoMoreLines
|
||||||
|
|
||||||
|
CalcSpriteEnd subroutine
|
||||||
|
; Calculate # of lines to draw for each sprite
|
||||||
|
; SIndx = 255 - ypos + scanline
|
||||||
|
lda SIndx0
|
||||||
|
beq .zero0
|
||||||
|
sec
|
||||||
|
sbc Scanline
|
||||||
|
eor #$ff
|
||||||
|
sta SIndx0
|
||||||
|
sec
|
||||||
|
sbc SSize0
|
||||||
|
.zero0
|
||||||
|
sta Temp
|
||||||
|
lda SIndx1
|
||||||
|
beq .zero1
|
||||||
|
sec
|
||||||
|
sbc Scanline
|
||||||
|
eor #$ff
|
||||||
|
sta SIndx1
|
||||||
|
sec
|
||||||
|
sbc SSize1
|
||||||
|
cmp Temp
|
||||||
|
bmi .cmp1 ; sindx0 < sindx1?
|
||||||
|
.zero1
|
||||||
|
lda Temp ; load higher number
|
||||||
|
.cmp1
|
||||||
|
; Compute the number of 8x lines in this section
|
||||||
|
eor #$ff
|
||||||
|
clc
|
||||||
|
adc #5
|
||||||
|
lsr
|
||||||
|
lsr
|
||||||
|
sta PFCount
|
||||||
|
rts
|
||||||
|
|
||||||
|
;;;
|
||||||
|
;;; COMMON ROUTINES
|
||||||
|
;;;
|
||||||
|
|
||||||
|
; We were too late to display a sprite.
|
||||||
|
; Put it earlier in the sort order and try next frame.
|
||||||
|
; X = sort index
|
||||||
|
.MissedSprite subroutine
|
||||||
|
; Have we already looked at all the sprites?
|
||||||
|
; Increment priority for this sort entry
|
||||||
|
inc Priority0,x
|
||||||
|
; Go to next sort index, until we get to the end
|
||||||
|
inx
|
||||||
|
stx CurIndex
|
||||||
|
.OutOfSprites
|
||||||
|
rts
|
||||||
|
; Try to assign the next sprite in the sort order into
|
||||||
|
; one of the two player slots.
|
||||||
|
; If sprite found, uses at least 3 scanlines for SetHorizPos.
|
||||||
|
FindAnotherSprite ; subroutine entry point
|
||||||
|
; Get the approximate scanline
|
||||||
|
GET_APPROX_SCANLINE
|
||||||
|
clc
|
||||||
|
adc #MinYDist
|
||||||
|
sta Scanline
|
||||||
|
FindAnotherSprite2 ; alternate entry point when scanline known
|
||||||
|
; Calculate the distance to next sprite
|
||||||
|
ldx CurIndex
|
||||||
|
cpx #NSprites
|
||||||
|
bcs .OutOfSprites
|
||||||
|
ldy Sorted0,x ; get sprite index # in Y-sorted order
|
||||||
|
lda YPos0,y ; get Y position of sprite
|
||||||
|
cmp Scanline ; SpriteY - Scanline
|
||||||
|
; Don't schedule the sprite if it's too soon or its scanline
|
||||||
|
; has already passed -- mark it missed
|
||||||
|
bmi .MissedSprite ; passed it? (or > 127 lines away)
|
||||||
|
; A sprite is starting soon, now we need to schedule it
|
||||||
|
; to either one of the player objects
|
||||||
|
lda XPos0,y
|
||||||
|
; Is player 1 available?
|
||||||
|
ldx SIndx1
|
||||||
|
bne .Plyr1NotReady
|
||||||
|
; Due to timing issues, we have artifacts if player 1 is
|
||||||
|
; too close to the left edge of the screen. So we'd prefer to
|
||||||
|
; put those sprites in the player 0 slot.
|
||||||
|
cmp #34 ; X < 34
|
||||||
|
bcc .Plyr1NotReady
|
||||||
|
; First let's set its horizontal offset
|
||||||
|
ldx #1
|
||||||
|
jsr SetHorizPos ; set horizontal position (does WSYNC)
|
||||||
|
; Assign the sprite's Y position to player 1
|
||||||
|
lda YPos0,y
|
||||||
|
sta SIndx1
|
||||||
|
; Set player 1 reflection/number/size flags
|
||||||
|
lda Flags0,y
|
||||||
|
sta REFP1 ; reflection flag
|
||||||
|
sta NUSIZ1 ; number-size
|
||||||
|
; Get index into SpriteDataMap (index * 4)
|
||||||
|
lda Shape0,y
|
||||||
|
asl
|
||||||
|
asl
|
||||||
|
tax
|
||||||
|
; Copy addresses of pixel/color maps to player 1
|
||||||
|
lda SpriteDataMap,x
|
||||||
|
sta PData1
|
||||||
|
lda SpriteDataMap+1,x
|
||||||
|
sta PData1+1
|
||||||
|
lda SpriteDataMap+2,x
|
||||||
|
sta PColr1
|
||||||
|
lda SpriteDataMap+3,x
|
||||||
|
sta PColr1+1
|
||||||
|
; Get the sprite height as the first byte of the color map
|
||||||
|
ldy #0
|
||||||
|
lda (PColr1),y
|
||||||
|
sta SSize1
|
||||||
|
inc SSize1 ; +1 to size
|
||||||
|
jmp .SetupDone
|
||||||
|
.Plyr1NotReady
|
||||||
|
ldx SIndx0
|
||||||
|
bne .NoNearSprite ; both players in use
|
||||||
|
; Player 0 is available
|
||||||
|
; This is essentially the same as the player 1 routine
|
||||||
|
ldx #0
|
||||||
|
jsr SetHorizPos
|
||||||
|
lda YPos0,y
|
||||||
|
sta SIndx0
|
||||||
|
lda Flags0,y
|
||||||
|
sta REFP0 ; reflection flag
|
||||||
|
sta NUSIZ0 ; number-size
|
||||||
|
lda Shape0,y
|
||||||
|
asl
|
||||||
|
asl
|
||||||
|
tax
|
||||||
|
lda SpriteDataMap,x
|
||||||
|
sta PData0
|
||||||
|
lda SpriteDataMap+1,x
|
||||||
|
sta PData0+1
|
||||||
|
lda SpriteDataMap+2,x
|
||||||
|
sta PColr0
|
||||||
|
lda SpriteDataMap+3,x
|
||||||
|
sta PColr0+1
|
||||||
|
ldy #0
|
||||||
|
lda (PColr0),y
|
||||||
|
sta SSize0
|
||||||
|
inc SSize0 ; +1 to size
|
||||||
|
.SetupDone
|
||||||
|
inc CurIndex ; go to next sprite in sort order
|
||||||
|
.NoNearSprite
|
||||||
|
rts
|
||||||
|
|
||||||
|
; called by 2-line kernel
|
||||||
|
DrawSprites2 subroutine
|
||||||
|
; Fetch sprite 0 values
|
||||||
|
lda SSize0 ; height in 2xlines
|
||||||
|
sec
|
||||||
|
isb SIndx0 ; INC yp0, then SBC yp0
|
||||||
|
bcs DoDraw0 ; inside bounds?
|
||||||
|
lda #0 ; no, load the padding offset (0)
|
||||||
|
DoDraw0
|
||||||
|
tay ; -> Y
|
||||||
|
lda (PColr0),y ; color for both lines
|
||||||
|
sta Colp0 ; -> colp0
|
||||||
|
lda (PData0),y ; bitmap for first line
|
||||||
|
sta GRP0 ; -> [GRP0] (delayed due to VDEL)
|
||||||
|
; Fetch sprite 1 values
|
||||||
|
lda SSize1 ; height in 2xlines
|
||||||
|
sec
|
||||||
|
isb SIndx1 ; INC yp0, then SBC yp0
|
||||||
|
bcs DoDraw1 ; inside bounds?
|
||||||
|
lda #0 ; no, load the padding offset (0)
|
||||||
|
DoDraw1
|
||||||
|
tay ; -> Y
|
||||||
|
lda (PColr1),y ; color for both lines
|
||||||
|
tax
|
||||||
|
lda (PData1),y ; bitmap for first line
|
||||||
|
tay
|
||||||
|
; WSYNC and store sprite values
|
||||||
|
lda Colp0
|
||||||
|
sta WSYNC
|
||||||
|
sty GRP1 ; GRP0 is also updated due to VDELP0 flag
|
||||||
|
stx COLUP1
|
||||||
|
sta COLUP0
|
||||||
|
; Return to caller
|
||||||
|
rts
|
||||||
|
|
||||||
|
; Perform one sort iteration
|
||||||
|
; X register contains sort index (0 to NSprites-1)
|
||||||
|
SwapSprites subroutine
|
||||||
|
; First compare Priority[i] and Priority[i+1]
|
||||||
|
lda Priority0,x
|
||||||
|
cmp Priority0+1,x
|
||||||
|
bcs .CompareYPos
|
||||||
|
; If Priority[i] < Priority[i+1], do the swap
|
||||||
|
; anyway after resetting priorities
|
||||||
|
lda #0
|
||||||
|
sta Priority0,x
|
||||||
|
sta Priority0+1,x ; reset
|
||||||
|
ldy Sorted0+1,x
|
||||||
|
bcc .DoSwap ; swap due to priority
|
||||||
|
.CompareYPos
|
||||||
|
; Compare Y[i] and Y[i+1]
|
||||||
|
ldy Sorted0,x
|
||||||
|
lda YPos0,y
|
||||||
|
ldy Sorted0+1,x
|
||||||
|
cmp YPos0,y
|
||||||
|
bcc .NoSwap ; Y[i] < Y[i+1]? don't swap
|
||||||
|
.DoSwap
|
||||||
|
; Swap Sorted[i] and Sorted[i+1]
|
||||||
|
lda Sorted0,x ; A <- Sorted[i]
|
||||||
|
sty Sorted0,x ; Y -> Sorted[i]
|
||||||
|
sta Sorted0+1,x ; A -> Sorted[i+1]
|
||||||
|
.NoSwap
|
||||||
|
rts
|
||||||
|
|
||||||
25
presets/vcs/setpos.inc
Normal file
25
presets/vcs/setpos.inc
Normal file
@ -0,0 +1,25 @@
|
|||||||
|
|
||||||
|
; SetHorizPos - Sets the horizontal position of an object.
|
||||||
|
; The X register contains the index of the desired object:
|
||||||
|
; X=0: player 0
|
||||||
|
; X=1: player 1
|
||||||
|
; X=2: missile 0
|
||||||
|
; X=3: missile 1
|
||||||
|
; X=4: ball
|
||||||
|
; NOTE: This version of the routine does a NEWLINE before executing.
|
||||||
|
; It does NOT do a HMOVE and HCLR.
|
||||||
|
SetHorizPos subroutine
|
||||||
|
sec ; set carry flag
|
||||||
|
sta WSYNC ; start a new line
|
||||||
|
.DivideLoop
|
||||||
|
sbc #15 ; subtract 15
|
||||||
|
bcs .DivideLoop ; branch until negative
|
||||||
|
eor #7 ; calculate fine offset
|
||||||
|
asl
|
||||||
|
asl
|
||||||
|
asl
|
||||||
|
asl
|
||||||
|
sta HMP0,x ; set fine offset
|
||||||
|
sta RESP0,x ; fix coarse position
|
||||||
|
rts ; return to caller
|
||||||
|
|
||||||
10
presets/vcs/xtimer.h
Normal file
10
presets/vcs/xtimer.h
Normal file
@ -0,0 +1,10 @@
|
|||||||
|
|
||||||
|
; Fetchs the approximate scanline (could be off by +/- 1)
|
||||||
|
; into A. Takes 11 or 14 cycles.
|
||||||
|
MAC GET_APPROX_SCANLINE
|
||||||
|
ldy INTIM
|
||||||
|
lda Timer2Scanline,y
|
||||||
|
bne .Ok
|
||||||
|
lda Timer2Scanline-1,y
|
||||||
|
.Ok
|
||||||
|
ENDM
|
||||||
41
presets/vcs/xtimer.inc
Normal file
41
presets/vcs/xtimer.inc
Normal file
@ -0,0 +1,41 @@
|
|||||||
|
|
||||||
|
; Set up macro for timer table
|
||||||
|
MAC TIMER_TABLE_SETUP
|
||||||
|
lda #255
|
||||||
|
sta WSYNC
|
||||||
|
sta TIM64T
|
||||||
|
ENDM
|
||||||
|
|
||||||
|
; Timer -> Scanline table
|
||||||
|
Timer2Scanline
|
||||||
|
.byte 215, 0,214,213,212,211,210, 0,209,208,207,206,205,204, 0,203
|
||||||
|
.byte 202,201,200,199, 0,198,197,196,195,194, 0,193,192,191,190,189
|
||||||
|
.byte 188, 0,187,186,185,184,183, 0,182,181,180,179,178, 0,177,176
|
||||||
|
.byte 175,174,173,172, 0,171,170,169,168,167, 0,166,165,164,163,162
|
||||||
|
.byte 0,161,160,159,158,157,156, 0,155,154,153,152,151, 0,150,149
|
||||||
|
.byte 148,147,146, 0,145,144,143,142,141,140, 0,139,138,137,136,135
|
||||||
|
.byte 0,134,133,132,131,130, 0,129,128,127,126,125,124, 0,123,122
|
||||||
|
.byte 121,120,119, 0,118,117,116,115,114, 0,113,112,111,110,109,108
|
||||||
|
.byte 0,107,106,105,104,103, 0,102,101,100, 99, 98, 0, 97, 96, 95
|
||||||
|
.byte 94, 93, 92, 0, 91, 90, 89, 88, 87, 0, 86, 85, 84, 83, 82, 0
|
||||||
|
.byte 81, 80, 79, 78, 77, 76, 0, 75, 74, 73, 72, 71, 0, 70, 69, 68
|
||||||
|
.byte 67, 66, 0, 65, 64, 63, 62, 61, 60, 0, 59, 58, 57, 56, 55, 0
|
||||||
|
.byte 54, 53, 52, 51, 50, 0, 49, 48, 47, 46, 45, 44, 0, 43, 42, 41
|
||||||
|
.byte 40, 39, 0, 38, 37, 36, 35, 34, 0, 33, 32, 31, 30, 29, 28, 0
|
||||||
|
.byte 27, 26, 25, 24, 23, 0, 22, 21, 20, 19, 18, 0, 17, 16, 15, 14
|
||||||
|
.byte 13, 12, 0, 11, 10, 9, 8, 7, 0, 6, 5, 4, 3, 2, 0, 1
|
||||||
|
|
||||||
|
|
||||||
|
; Pass: A = desired scanline
|
||||||
|
; Returns: Y = timer value - 1
|
||||||
|
align $10
|
||||||
|
WaitForScanline subroutine
|
||||||
|
ldy INTIM ; Fetch timer value
|
||||||
|
.Wait
|
||||||
|
cpy INTIM
|
||||||
|
beq .Wait ; Wait for it to change
|
||||||
|
sta WSYNC ; Sync with scan line
|
||||||
|
cmp Timer2Scanline,y ; lookup scanline
|
||||||
|
bcs WaitForScanline ; repeat until >=
|
||||||
|
rts
|
||||||
|
|
||||||
@ -38,6 +38,7 @@ const VCS_PRESETS = [
|
|||||||
{id:'examples/wavetable', chapter:36, name:'Wavetable Sound'},
|
{id:'examples/wavetable', chapter:36, name:'Wavetable Sound'},
|
||||||
{id:'examples/fracpitch', name:'Fractional Pitch'},
|
{id:'examples/fracpitch', name:'Fractional Pitch'},
|
||||||
{id:'examples/pal', name:'PAL Video Output'},
|
{id:'examples/pal', name:'PAL Video Output'},
|
||||||
|
{id:'examples/testlibrary', name:'VCS Library Demo'},
|
||||||
// {id:'examples/music2', name:'Pitch-Accurate Music'},
|
// {id:'examples/music2', name:'Pitch-Accurate Music'},
|
||||||
// {id:'examples/fullgame', name:'Thru Hike: The Game', title:'Thru Hike'},
|
// {id:'examples/fullgame', name:'Thru Hike: The Game', title:'Thru Hike'},
|
||||||
];
|
];
|
||||||
|
|||||||
Loading…
x
Reference in New Issue
Block a user