Add default key-binding for DRAG_RELATIVE (#117)

Ctrl-Button1 now has a relative drag using the XC_fleur cursor.
XC_fleur is normally the cursor for "size all" action, which has 4
arrows pointing to 4 directions.

Co-authored-by: NRK <nrk@disroot.org>

5 files changed, 8 insertions, 3 deletions

diff --git a/commands.c b/commands.c
index e52b381..b7fe9f4 100644
--- a/commands.c
+++ b/commands.c
@@ -338,7 +338,7 @@ bool ci_drag(arg_t mode)
 	if ((int)(img.w * img.zoom) <= win.w && (int)(img.h * img.zoom) <= win.h)
 		return false;
 
-	win_set_cursor(&win, CURSOR_DRAG);
+	win_set_cursor(&win, mode == DRAG_ABSOLUTE ? CURSOR_DRAG_ABSOLUTE : CURSOR_DRAG_RELATIVE);
 	win_cursor_pos(&win, &x, &y);
 	ox = x;
 	oy = y;
diff --git a/config.def.h b/config.def.h
index 39135ff..1085a39 100644
--- a/config.def.h
+++ b/config.def.h
@@ -158,6 +158,7 @@ static const keymap_t keys[] = {
 static const button_t buttons[] = {
 	/* modifiers    button            function              argument */
 	{ 0,            1,                i_cursor_navigate,    None },
+	{ ControlMask,  1,                i_drag,               DRAG_RELATIVE },
 	{ 0,            2,                i_drag,               DRAG_ABSOLUTE },
 	{ 0,            3,                g_switch_mode,        None },
 	{ 0,            4,                g_zoom,               +1 },
diff --git a/nsxiv.1 b/nsxiv.1
index 27b0914..04228a9 100644
--- a/nsxiv.1
+++ b/nsxiv.1
@@ -390,6 +390,9 @@ Panning:
 Pan the image according to the mouse cursor position in the window while
 keeping this button pressed down.
 .TP
+.B Ctrl-Button1
+Pan the image relative to the mouse cursor.
+.TP
 Zooming:
 .TP
 .B ScrollUp
diff --git a/nsxiv.h b/nsxiv.h
index 45d1772..8f288b3 100644
--- a/nsxiv.h
+++ b/nsxiv.h
@@ -99,7 +99,8 @@ typedef enum {
 
 typedef enum {
 	CURSOR_ARROW,
-	CURSOR_DRAG,
+	CURSOR_DRAG_ABSOLUTE,
+	CURSOR_DRAG_RELATIVE,
 	CURSOR_WATCH,
 	CURSOR_LEFT,
 	CURSOR_RIGHT,
diff --git a/window.c b/window.c
index 5e1392f..1c4eed6 100644
--- a/window.c
+++ b/window.c
@@ -51,7 +51,7 @@ static struct {
 	int name;
 	Cursor icon;
 } cursors[CURSOR_COUNT] = {
-	{ XC_left_ptr }, { XC_dotbox }, { XC_watch },
+	{ XC_left_ptr }, { XC_dotbox }, { XC_fleur }, { XC_watch },
 	{ XC_sb_left_arrow }, { XC_sb_right_arrow }
 };