Experimenting with extra scrollback; this is not in its final form yet.

1 files changed, 19 insertions, 0 deletions

diff --git a/src/screen.c b/src/screen.c
index 42a7e65..2d4436f 100644
--- a/src/screen.c
+++ b/src/screen.c
@@ -8,6 +8,10 @@
 
 #define SDLST ((u16 *)0x0230)
 
+/* if DOS isn't being used, the config will carve up the $0700-$1fff
+   area for extra scrollback. */
+unsigned int *bonus_addrs = (unsigned int *)0xf0;
+
 char scr_status[MAX_SCREENS];
 
 /* the screen that's currently displaying */
@@ -26,12 +30,20 @@ void scr_waitvcount(u8 c) {
 }
 
 static void scr_clear(char s) {
+	if(bonus_addrs[s]) {
+		memset(bonus_addrs[s], 0, 1000);
+		strcpy(bonus_addrs[s], "This is bonus scrollback!");
+	}
 	memset(screen_top_addrs[s], 0, 1000);
 	memset(screen_bot_addrs[s], 0, 1000);
 	memset(scr_names[s], 0, 32);
 }
 
 static void scr_scroll(char s) {
+	if(bonus_addrs[s]) {
+		memmove(bonus_addrs[s], bonus_addrs[s] + 40, 960);
+		memmove(bonus_addrs[s] + 960, screen_top_addrs[s], 40);
+	}
 	memmove(screen_top_addrs[s], screen_top_addrs[s] + 40, 960);
 	memmove(screen_top_addrs[s] + 960, screen_bot_addrs[s], 40);
 	memmove(screen_bot_addrs[s], screen_bot_addrs[s] + 40, 920);
@@ -115,6 +127,13 @@ void scr_display(char s) {
 	scr_show_status(s);
 }
 
+void scr_scrollback_bonus(void) {
+	if(bonus_addrs[scr_current]) {
+		scr_waitvcount(112);
+		*dlist_top_lms = (u16)bonus_addrs[scr_current];
+	}
+}
+
 void scr_scrollback(void) {
 	// OS.color2 = 0;
 	scr_waitvcount(112);