dos33fsprogs/graphics/hgr/hgr_font_4am/font_vmw_1x8.s
2023-08-27 00:48:36 -04:00

171 lines
2.5 KiB
ArmAsm

;license:MIT
;(c) 2023 by 4am
;
; drawing routines for Million Perfect Tiles Condensed
;
; Public functions:
; - DrawCondensedString
;
; VMW: commented, reformatted, minor changes, ca65 assembly
; hacked up some more
;------------------------------------------------------------------------------
; DrawCondensedString
;
; in: A/Y points to zero terminated string, with x-pos and y-pos at start
; out: clobbers all registers & flags
;------------------------------------------------------------------------------
DrawCondensedString:
; store the string location
sta OUTL
sty OUTH
DrawCondensedStringAgain:
ldy #0
lda (OUTL), Y ; get xpos
sta CH ; save the X column offset
iny
lda (OUTL),Y ; get ypos
tay
; add two to string pointer
clc
lda OUTL
adc #2
sta dcb_loop+1
lda #0
adc OUTH
sta dcb_loop+2
; row0
lda hposn_low, Y ; get low memory offset
clc
adc CH ; add in x-coord
sta dcb_row0+4
lda hposn_high, Y ; get high memory offset
sta dcb_row0+5 ; save it out
iny ; go to next row
; row1
lda hposn_low, Y
adc CH
sta dcb_row1+4
lda hposn_high, Y
sta dcb_row1+5
iny
; row2
lda hposn_low, Y
adc CH
sta dcb_row2+4
lda hposn_high, Y
sta dcb_row2+5
iny
; row3
lda hposn_low, Y
adc CH
sta dcb_row3+4
lda hposn_high, Y
sta dcb_row3+5
iny
; row4
lda hposn_low, Y
adc CH
sta dcb_row4+4
lda hposn_high, Y
sta dcb_row4+5
iny
; row5
lda hposn_low, Y
adc CH
sta dcb_row5+4
lda hposn_high, Y
sta dcb_row5+5
iny
; row6
lda hposn_low, Y
adc CH
sta dcb_row6+4
lda hposn_high, Y
sta dcb_row6+5
iny
; row7
lda hposn_low, Y
adc CH
sta dcb_row7+4
lda hposn_high, Y
sta dcb_row7+5
ldx #0
dcb_loop:
dcb_loop_smc:
ldy $FDFD, X ; load next char into Y
beq dcb_done
; unrolled loop to write out each line
dcb_row0:
lda CondensedRow0-$19, Y ; get 1-byte font row
sta $FDFD, X ; write out to graphics mem
dcb_row1:
lda CondensedRow1-$19, Y
sta $FDFD, X
dcb_row2:
lda CondensedRow2-$19, Y
sta $FDFD, X
dcb_row3:
lda CondensedRow3-$19, Y
sta $FDFD, X
dcb_row4:
lda CondensedRow4-$19, Y
sta $FDFD, X
dcb_row5:
lda CondensedRow5-$19, Y
sta $FDFD, X
dcb_row6:
lda CondensedRow6-$19, Y
sta $FDFD, X
dcb_row7:
lda CondensedRow7-$19, Y
sta $FDFD, X
inx ; move to next
bne dcb_loop ; bra (well, as long as string
; is less than 255 chars)
dcb_done:
; point to location after
; need to be +3 currently as OUTL not updated earlier
inx
inx
sec ; always add 1
txa
adc OUTL
sta OUTL
lda #0
adc OUTH
sta OUTH
rts