screen_play: repaint hscrolling only if selected item is wide

When the "scroll" option is active, ncmpc repainted the whole screen
with each tick, even if the selected item is not wider than the
screen.  This wasted a lot of CPU cycles.

diff --git a/src/screen_play.c b/src/screen_play.c
index fb5e82b1d3dddad4f48471dcc8e819a636bda7a9..ed17499164d0f5bca8a4636e5372129127ab4d8d 100644 (file)
--- a/src/screen_play.c
+++ b/src/screen_play.c
@@ -52,6 +52,8 @@ typedef struct
        GList **dir_list;
        struct mpdclient *c;
 } completion_callback_data_t;
+
+static bool must_scroll;
 #endif
 
 static struct mpdclient_playlist *playlist;
@@ -141,6 +143,8 @@ list_callback(unsigned idx, bool *highlight, char **second_column, G_GNUC_UNUSED
                        static unsigned current_song;
                        char *tmp;
 
+                       must_scroll = true;
+
                        if (current_song != lw->selected) {
                                st.offset = 0;
                                current_song = lw->selected;
@@ -537,6 +541,10 @@ play_title(char *str, size_t size)
 static void
 play_paint(void)
 {
+#ifndef NCMPC_MINI
+       must_scroll = false;
+#endif
+
        list_window_paint(lw, list_callback, NULL);
 }
 
@@ -558,7 +566,7 @@ play_update(struct mpdclient *c)
 
                playlist_repaint();
 #ifndef NCMPC_MINI
-       } else if (options.scroll) {
+       } else if (options.scroll && must_scroll) {
                /* always repaint if horizontal scrolling is
                   enabled */
                playlist_repaint();