From 19a124e80614cf294b896eaf6e603eb52055114a Mon Sep 17 00:00:00 2001
From: Benno Schulenberg <bensberg@telfort.nl>
Date: Sun, 31 May 2020 16:14:43 +0200
Subject: [PATCH] display: avoid an additional redrawing when redrawing the
 screen

When resizing the screen or toggling the help lines or refreshing
the screen with ^L, what used to be total_refresh() would first call
what used to be total_redraw(), to tell ncurses to redraw whatever
had been on the screen so far, before proceeding to fully redraw the
content of the title bar and the edit window and the bottom bars.
That was duplicate work.

Thus, rename total_redraw() to total_refresh(), so that ^L in the
edit window, help viewer, and file browser will redraw the screen
just once.  This also preserves whatever was on the status bar
(when --quickblank isn't used).

Rename the old total_refresh() to draw_all_subwindows() and call
this routine when resizing the screen or toggling the help lines
or returning from the credits crawl.
---
 src/browser.c | 2 +-
 src/help.c    | 2 +-
 src/nano.c    | 4 ++--
 src/proto.h   | 2 +-
 src/winio.c   | 7 +++----
 5 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/src/browser.c b/src/browser.c
index fc37dff2..e7dd6ae2 100644
--- a/src/browser.c
+++ b/src/browser.c
@@ -154,7 +154,7 @@ char *do_browser(char *path)
 		func = interpret(&kbinput);
 
 		if (func == total_refresh) {
-			total_redraw();
+			total_refresh();
 #ifndef NANO_TINY
 			/* Simulate a window resize to force a directory reread. */
 			kbinput = KEY_WINCH;
diff --git a/src/help.c b/src/help.c
index 9df31579..6873b26e 100644
--- a/src/help.c
+++ b/src/help.c
@@ -194,7 +194,7 @@ void show_help(void)
 		func = interpret(&kbinput);
 
 		if (func == total_refresh) {
-			total_redraw();
+			total_refresh();
 		} else if (ISSET(SHOW_CURSOR) && (func == do_left || func == do_right ||
 											func == do_up || func == do_down)) {
 			func();
diff --git a/src/nano.c b/src/nano.c
index 20533640..4d1b568d 100644
--- a/src/nano.c
+++ b/src/nano.c
@@ -1053,7 +1053,7 @@ void regenerate_screen(void)
 	/* If we have an open buffer, redraw the contents of the subwindows. */
 	if (openfile) {
 		ensure_firstcolumn_is_aligned();
-		total_refresh();
+		draw_all_subwindows();
 	}
 }
 
@@ -1071,7 +1071,7 @@ void do_toggle(int flag)
 	switch (flag) {
 		case NO_HELP:
 			window_init();
-			total_refresh();
+			draw_all_subwindows();
 			break;
 #ifdef ENABLE_MOUSE
 		case USE_MOUSE:
diff --git a/src/proto.h b/src/proto.h
index 9bf0cd80..3ea1dcc1 100644
--- a/src/proto.h
+++ b/src/proto.h
@@ -639,8 +639,8 @@ size_t actual_last_column(size_t leftedge, size_t column);
 void edit_redraw(linestruct *old_current, update_type manner);
 void edit_refresh(void);
 void adjust_viewport(update_type location);
-void total_redraw(void);
 void total_refresh(void);
+void draw_all_subwindows(void);
 void do_cursorpos(bool force);
 void do_cursorpos_void(void);
 void spotlight(size_t from_col, size_t to_col);
diff --git a/src/winio.c b/src/winio.c
index 2533e24d..2937412d 100644
--- a/src/winio.c
+++ b/src/winio.c
@@ -3309,7 +3309,7 @@ void adjust_viewport(update_type manner)
 }
 
 /* Unconditionally redraw the entire screen. */
-void total_redraw(void)
+void total_refresh(void)
 {
 #ifdef USE_SLANG
 	/* Slang curses emulation brain damage, part 4: Slang doesn't define
@@ -3323,9 +3323,8 @@ void total_redraw(void)
 
 /* Redraw the entire screen, then refresh the title bar and the content of
  * the edit window (when not in the file browser), and the bottom bars. */
-void total_refresh(void)
+void draw_all_subwindows(void)
 {
-	total_redraw();
 	if (currmenu != MBROWSER && currmenu != MWHEREISFILE && currmenu != MGOTODIR)
 		titlebar(title);
 #ifdef ENABLE_HELP
@@ -3620,6 +3619,6 @@ void do_credits(void)
 	scrollok(edit, FALSE);
 	nodelay(edit, FALSE);
 
-	total_refresh();
+	draw_all_subwindows();
 }
 #endif /* ENABLE_EXTRA */