cc65/libsrc/geos-common/conio/cclear.s

;
; Maciej 'YTM/Elysium' Witkowiak
;
; 06.03.2002

; void cclearxy (unsigned char x, unsigned char y, unsigned char length);
; void cclear (unsigned char length);

	    .export _cclearxy, _cclear
	    .import popa, _gotoxy, fixcursor
	    .importzp cursor_x, cursor_y, cursor_c

	    .include "jumptab.inc"
	    .include "geossym.inc"

_cclearxy:
	pha	    		; Save the length
	jsr popa		; Get y
	jsr _gotoxy		; Call this one, will pop params
	pla			; Restore the length

_cclear:
	cmp #0			; Is the length zero?
	beq L9  		; Jump if done
	tax
	lda cursor_x		; left start
	sta r3L
	lda cursor_x+1
	sta r3L+1
	lda cursor_y		; level
	sta r2L
	clc
	adc #8
	sta r2H
	txa			; right end
	clc
	adc cursor_c
	sta cursor_c
	sta r4L
	ldx #r4
	ldy #3
	jsr DShiftLeft
	lda curPattern		; store current pattern
	pha
	lda #0			; set pattern to clear
	jsr SetPattern
	jsr Rectangle
	pla
	jsr SetPattern		; restore pattern
	jsr fixcursor
L9:	rts