From 66cfc3e189df8362aa77f7a2f3e2495bf00ab2c3 Mon Sep 17 00:00:00 2001
From: John Tsiombikas <nuclear@member.fsf.org>
Date: Wed, 11 Oct 2023 14:31:00 +0300
Subject: [PATCH] simplistic mouse cursor

---
 src/kern/main.c  |   56 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/kern/psaux.c |    6 ++++++
 src/kern/psaux.h |    1 +
 3 files changed, 63 insertions(+)

diff --git a/src/kern/main.c b/src/kern/main.c
index 6c37116..2dd7465 100644
--- a/src/kern/main.c
+++ b/src/kern/main.c
@@ -13,11 +13,16 @@
 unsigned char *framebuf, *vmem = (unsigned char*)0xa0000;
 
 static int quit;
+static int mx, my;
+
+static void draw_cursor(int mx, int my);
 
 
 int main(void)
 {
 	int key;
+	int prev_mx = 0, prev_my = 0;
+	unsigned int mbn, prev_mbn = 0, mbn_diff;
 
 	init_segm();
 	init_intr();
@@ -37,10 +42,33 @@ int main(void)
 		goto end;
 	}
 
+	set_mouse_pos(160, 100);
+
 	for(;;) {
 		if((key = kb_getkey()) >= 0) {
 			game_keyboard(key, 1);
 		}
+
+		mbn = mouse_state(&mx, &my);
+
+		if((mbn_diff = mbn ^ prev_mbn) != 0) {
+			if(mbn_diff & 1) {
+				game_mouse(0, mbn & 1, mx, my);
+			}
+			if(mbn_diff & 2) {
+				game_mouse(2, mbn & 2, mx, my);
+			}
+			if(mbn_diff & 4) {
+				game_mouse(1, mbn & 4, mx, my);
+			}
+		}
+		if(mx != prev_mx || my != prev_my) {
+			game_motion(mx, my);
+		}
+		prev_mbn = mbn;
+		prev_mx = mx;
+		prev_my = my;
+
 		if(quit) break;
 		game_draw();
 	}
@@ -64,5 +92,33 @@ void game_quit(void)
 
 void game_swap_buffers(void)
 {
+	draw_cursor(mx, my);
+
 	memcpy(vmem, framebuf, 64000);
 }
+
+#define CUR_SZ	4
+
+static void draw_cursor(int mx, int my)
+{
+	int i, sx, ex, sy, ey, xlen, ylen;
+	unsigned char *ptr;
+
+	sx = mx < CUR_SZ ? mx : mx - CUR_SZ;
+	ex = mx >= 320 - CUR_SZ ? CUR_SZ - 1 : mx + CUR_SZ;
+	xlen = ex - sx + 1;
+	sy = my < CUR_SZ ? my : my - CUR_SZ;
+	ey = my >= 200 - CUR_SZ ? CUR_SZ - 1 : my + CUR_SZ;
+	ylen = ey - sy + 1;
+
+	ptr = framebuf + (my << 8) + (my << 6) + sx;
+	for(i=0; i<xlen; i++) {
+		ptr[i] ^= 0xff;
+	}
+
+	ptr = framebuf + (sy << 8) + (sy << 6) + mx;
+	for(i=0; i<ylen; i++) {
+		*ptr ^= 0xff;
+		ptr += 320;
+	}
+}
diff --git a/src/kern/psaux.c b/src/kern/psaux.c
index a0fb58d..f9f6058 100644
--- a/src/kern/psaux.c
+++ b/src/kern/psaux.c
@@ -95,6 +95,12 @@ void set_mouse_bounds(int x0, int y0, int x1, int y1)
 	bounds[3] = y1;
 }
 
+void set_mouse_pos(int x, int y)
+{
+	mx = x;
+	my = y;
+}
+
 unsigned int mouse_state(int *xp, int *yp)
 {
 	if(!intr_mode) {
diff --git a/src/kern/psaux.h b/src/kern/psaux.h
index 7acc3f6..9c4c265 100644
--- a/src/kern/psaux.h
+++ b/src/kern/psaux.h
@@ -26,6 +26,7 @@ void init_psaux(void);
 
 int have_mouse(void);
 
+void set_mouse_pos(int x, int y);
 void set_mouse_bounds(int x0, int y0, int x1, int y1);
 unsigned int mouse_state(int *xp, int *yp);
 
-- 
1.7.10.4