dos33fsprogs/graphics/hgr/sierpinski/move_right.s
Vince Weaver 505a608549 hgr: triangles: investigate filled triangles
might fake it for now
2021-06-21 00:51:32 -04:00

72 lines
866 B
ArmAsm

GBASL = $26
GBASH = $27
HGR_BITS = $1C
HGR_HMASK = $30
HGR_X = $E0
HGR_Y = $E2
HGR_COLOR = $E4
HGR_HORIZ = $E5
HGRPAGE = $E6
SAVEX = $FD
TEMP = $FE
OLD = $FF
PAGE0 = $C054
PAGE1 = $C055
HGR = $F3E2
HGR2 = $F3D8
HCLR = $F3F2
HPOSN = $F411
HPLOT0 = $F457 ;; plot at (Y,X), (A)
HPLOT1 = $F45A
MOVE_RIGHT = $F48A
HCOLOR1 = $F6F0
WAIT = $FCA8 ;; delay 1/2(26+27A+5A^2) us
tiny:
jsr HGR2 ; clear page1
; A is 0 after
ldx #3
jsr HCOLOR1
tiny_yloop:
ldy #0
ldx #0 ; XX = 0
yy_smc:
lda #0 ; Y co-ord
jsr HPOSN ; plot at (Y,X), (A)
tiny_xloop:
; lda (GBASL),Y
; eor HGR_BITS
; and HGR_HMASK
; eor (GBASL),Y
; sta (GBASL),Y
; lda HGR_BITS
; eor (GBASL),Y
; and HGR_HMASK
; eor (GBASL),Y
; sta (GBASL),Y
jsr HPLOT1
jsr MOVE_RIGHT ; trashes A
cpy #39
bne tiny_xloop
inc yy_smc+1
jmp tiny_yloop