dos33fsprogs/graphics/hgr/xdraw/tiny_center.s
2021-05-09 00:53:32 -04:00

80 lines
1.4 KiB
ArmAsm

; Tiny Tiny
; zero page locations
HGR_SHAPE = $1A
HGR_SHAPE2 = $1B
HGR_BITS = $1C
GBASL = $27
GBASH = $28
A5H = $45
XREG = $46
YREG = $47
; C0-CF should be clear
; D0-DF?? D0-D5 = HGR scratch?
HGR_DX = $D0 ; HGLIN
HGR_DX2 = $D1 ; HGLIN
HGR_DY = $D2 ; HGLIN
HGR_QUADRANT = $D3
HGR_E = $D4
HGR_E2 = $D5
HGR_X = $E0
HGR_X2 = $E1
HGR_Y = $E2
HGR_COLOR = $E4
HGR_HORIZ = $E5
HGR_SCALE = $E7
HGR_SHAPE_TABLE = $E8
HGR_SHAPE_TABLE2= $E9
HGR_COLLISIONS = $EA
HGR_ROTATION = $F9
FRAME = $FC
XPOS = $FD
YPOS = $FF
; ROM calls
HGR2 = $F3D8
HPOSN = $F411
XDRAW0 = $F65D
XDRAW1 = $F661
RESTORE = $FF3F
.zeropage
.globalzp rot_smc
tiny_tiny:
jsr HGR2 ; Hi-res, full screen ; E7/E8/E9
; Y=0, A=0 after this call ; scale/shape
lda #40 ; EA/EB collision
sta HGR_SCALE ; EC ED
tiny_loop:
inc rot_smc+1 ; EE EF
; setup X and Y co-ords
ldy #0 ; Y always 0 ; F0 F1
ldx #140 ; F2 F3
lda #96 ; F4
jsr HPOSN ; X= (y,x) Y=(a) ; F5 F6 F7
; saves Y/X/A to HGR_Y, HGR_X, HGR_X+1
; after, Y = X/7
; after, y = $14 = 20, always
; A=FF, X=F9
ldx #<shape_table ; point to our shape ; F8 F9
ldy #0 ; FA FB
rot_smc:
lda #0 ; ROT=0 ; FC FD
jsr XDRAW0 ; XDRAW 1 AT X,Y ; FE FF 100
; Both A and X are 0 at exit
; Z flag set on exit
beq tiny_loop ; bra
shape_table:
; .byte $2D,0 ; shape data
.byte $3A,$DB,$0 ; accidentally found at addr $0004
; RT RT is 00 101 101 = 2D