Ticket #3130: patch-panel-scroll-center.diff

doc/man/mc.1.in

@@ -2077 +2077 @@
 cursor reaches the end or the beginning of the panel, otherwise it
 will just scroll a file at a time.
 .PP
+.I Center scrolling.
+If set, panel will scroll when the cursor reaches the middle of the
+panel, only hitting the top or bottom of the panel when actually on
+the first or last file. This behavior applies when scrolling one file
+at a time, and does not apply to the page up/down keys.
+.PP
 .I Mouse page scrolling.
 Controls whenever scrolling with the mouse wheel is done by pages or
 line by line on the panels.

src/setup.h

@@ -48 +48 @@
     gboolean navigate_with_arrows;      /* If TRUE: l&r arrows are used to chdir if the input line is empty */
     gboolean scroll_pages;      /* If TRUE, panel is scrolled by half the display when the cursor reaches
                                    the end or the beginning of the panel */
+    gboolean scroll_center;     /* If TRUE, scroll when the cursor hits the middle of the panel */
     gboolean mouse_move_pages;  /* Scroll page/item using mouse wheel */
     gboolean filetype_mode;     /* If TRUE then add per file type hilighting */
     gboolean permission_mode;   /* If TRUE, we use permission hilighting */

src/setup.c

@@ -142 +142 @@
     .auto_save_setup = FALSE,
     .navigate_with_arrows = FALSE,
     .scroll_pages = TRUE,
+    .scroll_center = FALSE,
     .mouse_move_pages = TRUE,
     .filetype_mode = TRUE,
     .permission_mode = FALSE,
@@ -400 +401 @@
     { "auto_save_setup_panels", &panels_options.auto_save_setup },
     { "navigate_with_arrows", &panels_options.navigate_with_arrows },
     { "panel_scroll_pages", &panels_options.scroll_pages },
+    { "panel_scroll_center", &panels_options.scroll_center },
     { "mouse_move_pages",  &panels_options.mouse_move_pages },
     { "filetype_mode", &panels_options.filetype_mode },
     { "permission_mode", &panels_options.permission_mode },

src/filemanager/boxes.c

@@ -554 +554 @@
                     QUICK_CHECKBOX (N_("L&ynx-like motion"), &panels_options.navigate_with_arrows,
                                     NULL),
                     QUICK_CHECKBOX (N_("Pa&ge scrolling"), &panels_options.scroll_pages, NULL),
+                    QUICK_CHECKBOX (N_("Center &scrolling"), &panels_options.scroll_center, NULL),
                     QUICK_CHECKBOX (N_("&Mouse page scrolling"), &panels_options.mouse_move_pages,
                                     NULL),
                 QUICK_STOP_GROUPBOX,

src/filemanager/panel.c

@@ -2019 +2019 @@
             panel->top_file = panel->dir.len - ITEMS (panel);
         paint_dir (panel);
     }
+    else if (panels_options.scroll_center &&
+             (panel->selected - panel->top_file) > (ITEMS (panel) / 2))
+    {
+        /* Scroll window when cursor is halfway down */
+        panel->top_file++;
+        if (panel->top_file > panel->dir.len - ITEMS (panel))
+            panel->top_file = panel->dir.len - ITEMS (panel);
+    }
     select_item (panel);
 }
 
@@ -2040 +2048 @@
             panel->top_file = 0;
         paint_dir (panel);
     }
+    else if (panels_options.scroll_center &&
+             panel->selected < (panel->top_file + ITEMS (panel) / 2))
+    {
+        /* Scroll window when cursor is halfway up */
+        panel->top_file--;
+        if (panel->top_file < 0)
+            panel->top_file = 0;
+    }
     select_item (panel);
 }