; 32B weird line pattern ; zero page locations HGR_SHAPE = $1A HGR_SHAPE2 = $1B HGR_BITS = $1C GBASL = $26 GBASH = $27 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 HGR = $F3E2 HPOSN = $F411 XDRAW0 = $F65D XDRAW1 = $F661 RESTORE = $FF3F tiny_xdraw: jsr HGR2 ; Hi-res, full screen ; 3 ; Y=0, A=0 after this call lda #10 sta HGR_SCALE ; A and Y are 0 here. ; X is left behind by the boot process? ldy #0 ldx #100 lda #100 jsr HPOSN ; set screen position to X= (y,x) Y=(a) ; saves X,Y,A to zero page ; after Y= orig X/7 ; A and X are ?? tiny_loop: ; values for shape table ; Y X ; 00 E7 = neat ; 00 EB = OK ; 00 EF = good ; F0 01 = cool, let's go with it ldx #shape_table ; point to top byte of shape address ; ROT in A ; this will be 0 2nd time through loop, arbitrary otherwise lda #1 ; ROT=0 jsr XDRAW0 ; XDRAW 1 AT X,Y ; Both A and X are 0 at exit ; Z flag set on exit ; Y varies beq tiny_loop ; bra shape_table: ; .byte $01,$00, .byte $04,$00,$25,$35,$00