From a5a8694340fd315fe3dc824e6bf7857110ad500f Mon Sep 17 00:00:00 2001
From: Vince Weaver <vincent.weaver@maine.edu>
Date: Fri, 18 Jun 2021 15:56:51 -0400
Subject: [PATCH] hgr: vgi: line support

---
 graphics/hgr/vgi/Makefile    |  2 +-
 graphics/hgr/vgi/vgi.s       |  5 +++--
 graphics/hgr/vgi/vgi_lines.s | 40 ++++++++++++++++++++++++++++++++++++
 3 files changed, 44 insertions(+), 3 deletions(-)
 create mode 100644 graphics/hgr/vgi/vgi_lines.s

diff --git a/graphics/hgr/vgi/Makefile b/graphics/hgr/vgi/Makefile
index 97ed40da..8c6727ea 100644
--- a/graphics/hgr/vgi/Makefile
+++ b/graphics/hgr/vgi/Makefile
@@ -25,7 +25,7 @@ VGI:	vgi.o
 	ld65 -o VGI vgi.o -C $(LINKERSCRIPTS)/apple2_c00.inc
 
 vgi.o: clock.data \
-	vgi.s vgi_clearscreen.s vgi_rectangle.s vgi_circles.s
+	vgi.s vgi_clearscreen.s vgi_rectangle.s vgi_circles.s vgi_lines.s
 	ca65 -o vgi.o vgi.s -l vgi.lst
 
 
diff --git a/graphics/hgr/vgi/vgi.s b/graphics/hgr/vgi/vgi.s
index 24db7160..f31c653c 100644
--- a/graphics/hgr/vgi/vgi.s
+++ b/graphics/hgr/vgi/vgi.s
@@ -55,8 +55,8 @@ vgi_rts_table:
 	.word vgi_simple_rectangle-1	; 1 = simple rectangle
 	.word vgi_circle-1		; 2 = plain circle
 	.word vgi_filled_circle-1	; 3 = filled circle
-	.word all_done-1		; 4 = dot
-	.word all_done-1		; 5 = line to
+	.word vgi_point-1		; 4 = dot
+	.word vgi_lineto-1		; 5 = line to
 	.word all_done-1
 	.word all_done-1
 	.word all_done-1
@@ -75,5 +75,6 @@ all_done:
 .include "vgi_clearscreen.s"
 .include "vgi_rectangle.s"
 .include "vgi_circles.s"
+.include "vgi_lines.s"
 
 .include "clock.data"
diff --git a/graphics/hgr/vgi/vgi_lines.s b/graphics/hgr/vgi/vgi_lines.s
new file mode 100644
index 00000000..ffae4521
--- /dev/null
+++ b/graphics/hgr/vgi/vgi_lines.s
@@ -0,0 +1,40 @@
+; VGI Lines
+
+	;========================
+	; VGI point
+	;========================
+
+	VGI_PCOLOR	= P0
+	VGI_PX		= P1
+	VGI_PY		= P2
+
+vgi_point:
+	ldx	VGI_PCOLOR
+	lda	COLORTBL,X
+	sta	HGR_COLOR
+
+	ldy	#0
+	ldx	VGI_PX
+	lda	VGI_PY
+
+	jsr	HPLOT0		; plot at (Y,X), (A)
+
+	jmp	vgi_loop
+
+
+
+
+	;========================
+	; VGI line to
+	;========================
+	VGI_LX	= P0
+	VGI_LY	= P1
+
+vgi_lineto:
+	ldx	#0
+	ldy	VGI_LY
+	lda	VGI_LX
+
+	jsr	HGLIN		; line to (X,A),(Y)
+
+	jmp	vgi_loop