commit 64923c4b5e7b04f634d578539ccbe12d34d63995
from: Omar Polo <op@omarpolo.com>
date: Thu Jul 15 13:07:17 2021 UTC

fix the scroll commands

forward_line(buffer, body_lines) is not a real scrolling.  We need to
move the top_line to have a nice effect.

commit - c1a72389c0083bb0722cec6ca5f1589d3f6b7c0b
commit + 64923c4b5e7b04f634d578539ccbe12d34d63995
blob - 20f703053c426d868e4fe21f1a84088c1292e982
blob + 567015ddcda859e1cf828c5f37e40fc1d2dc869f
--- cmd.c
+++ cmd.c
@@ -179,13 +179,30 @@ cmd_scroll_line_down(struct buffer *buffer)
 void
 cmd_scroll_up(struct buffer *buffer)
 {
-	forward_line(buffer, -1*body_lines);
+	struct vline	*vl;
+	int		 i;
+
+	for (i = 0; i < body_lines; ++i) {
+		vl = TAILQ_PREV(buffer->top_line, vhead, vlines);
+		if (vl == NULL)
+			break;
+		buffer->top_line = vl;
+		forward_line(buffer, -1);
+	}
 }
 
 void
 cmd_scroll_down(struct buffer *buffer)
 {
-	forward_line(buffer, body_lines);
+	int i;
+
+	for (i = 0; i < body_lines; ++i) {
+		if (!forward_line(buffer, +1))
+			break;
+
+		buffer->top_line = TAILQ_NEXT(buffer->top_line,
+		    vlines);
+	}
 }
 
 void