hgr: vgi: forgot file

graphics/hgr/vgi/vgi_rectangle.s

@@ -0,0 +1,99 @@
+; VGI Rectangle
+
+
+; COUNT = $75
+
+
+	;=================================
+	; Simple Rectangle
+	;=================================
+	VGI_RCOLOR	= P0
+	VGI_RX1		= P1
+	VGI_RY1		= P2
+	VGI_RXRUN	= P3
+	VGI_RYRUN	= P4
+
+vgi_simple_rectangle:
+
+simple_rectangle_loop:
+	lda	VGI_RCOLOR
+
+	asl		; nibble swap by david galloway
+	adc	#$80
+	rol
+	asl
+	adc	#$80
+	rol
+
+	sta	VGI_RCOLOR
+
+	and	#$f
+	tax
+
+	lda	COLORTBL,X
+	sta	HGR_COLOR
+
+	ldx	VGI_RX1		; X1 into X
+	lda	VGI_RY1		; Y1 into A
+	ldy	#0		; always 0
+	jsr	HPOSN		; (Y,X),(A)  (values stores in HGRX,XH,Y)
+
+
+	lda	VGI_RXRUN	; XRUN into A
+	ldx	#0		; always 0
+	ldy	#0		; relative Y is 0
+	jsr	HLINRL		; (X,A),(Y)
+
+	inc	VGI_RY1
+	dec	VGI_RYRUN
+	bne	simple_rectangle_loop
+
+	jmp	vgi_loop
+
+
+
+
+
+	;=================================
+	; Dithered Rectangle
+	;=================================
+;	VGI_RCOLOR	= P0
+;	VGI_RX1		= P1
+;	VGI_RY1		= P2
+;	VGI_RXRUN	= P3
+;	VGI_RYRUN	= P4
+	VGI_RCOLOR2	= P5
+
+vgi_dithered_rectangle:
+
+dithered_rectangle_loop:
+	lda	COUNT
+	and	#$1
+	beq	even_color
+odd_color:
+	lda	VGI_RCOLOR
+	jmp	save_color
+even_color:
+	lda	VGI_RCOLOR2
+save_color:
+	sta	HGR_COLOR
+
+	inc	COUNT
+
+	ldx	VGI_RX1		; X1 into X
+	lda	VGI_RY1		; Y1 into A
+	ldy	#0		; always 0
+	jsr	HPOSN		; (Y,X),(A)  (values stores in HGRX,XH,Y)
+
+
+	lda	VGI_RXRUN	; XRUN into A
+	ldx	#0		; always 0
+	ldy	#0		; relative Y is 0
+	jsr	HLINRL		; (X,A),(Y)
+
+	inc	VGI_RY1
+	dec	VGI_RYRUN
+	bne	dithered_rectangle_loop
+
+	jmp	vgi_loop
+