Improve mouse support

None of the mouse mappings uses a keyboard modifier, making it possible to
access the most basic features by only using the mouse.

Next/previous image with left button depending on cursor position, middle
button for dragging, right button for switching to thumnail mode and wheel for
zooming.

Users can keep the old behaviour by simply not adapting the changes to the
buttons array in config.def.h to their config.h file.

8 files changed, 52 insertions, 34 deletions

diff --git a/Makefile b/Makefile
index 2c5b701..9e29648 100644
--- a/Makefile
+++ b/Makefile
@@ -1,4 +1,4 @@
-VERSION := git-20171005
+VERSION := git-20171006
 
 all: sxiv
 
diff --git a/commands.c b/commands.c
index 522413d..6c5fb1a 100644
--- a/commands.c
+++ b/commands.c
@@ -33,6 +33,7 @@
 void remove_file(int, bool);
 void load_image(int);
 void open_info(void);
+int ptr_third_x(void);
 void redraw(void);
 void reset_cursor(void);
 void animate(void);
@@ -281,6 +282,11 @@ bool ci_navigate(arg_t n)
 	}
 }
 
+bool ci_cursor_navigate(arg_t _)
+{
+	return ci_navigate(ptr_third_x() - 1);
+}
+
 bool ci_alternate(arg_t _)
 {
 	load_image(alternate);
diff --git a/commands.lst b/commands.lst
index a658dd4..bf9e3ed 100644
--- a/commands.lst
+++ b/commands.lst
@@ -16,6 +16,7 @@ G_CMD(navigate_marked)
 G_CMD(change_gamma)
 
 I_CMD(navigate)
+I_CMD(cursor_navigate)
 I_CMD(alternate)
 I_CMD(navigate_frame)
 I_CMD(toggle_animation)
diff --git a/config.def.h b/config.def.h
index e211c0d..5af745d 100644
--- a/config.def.h
+++ b/config.def.h
@@ -150,17 +150,11 @@ static const keymap_t keys[] = {
 /* mouse button mappings for image mode: */
 static const button_t buttons[] = {
 	/* modifiers    button            function              argument */
-	{ 0,            1,                i_navigate,           +1 },
-	{ 0,            3,                i_navigate,           -1 },
+	{ 0,            1,                i_cursor_navigate,    None },
 	{ 0,            2,                i_drag,               None },
-	{ 0,            4,                i_scroll,             DIR_UP },
-	{ 0,            5,                i_scroll,             DIR_DOWN },
-	{ ShiftMask,    4,                i_scroll,             DIR_LEFT },
-	{ ShiftMask,    5,                i_scroll,             DIR_RIGHT },
-	{ 0,            6,                i_scroll,             DIR_LEFT },
-	{ 0,            7,                i_scroll,             DIR_RIGHT },
-	{ ControlMask,  4,                g_zoom,               +1 },
-	{ ControlMask,  5,                g_zoom,               -1 },
+	{ 0,            3,                g_switch_mode,        None },
+	{ 0,            4,                g_zoom,               +1 },
+	{ 0,            5,                g_zoom,               -1 },
 };
 
 #endif
diff --git a/main.c b/main.c
index 5a828a9..406c2b9 100644
--- a/main.c
+++ b/main.c
@@ -98,6 +98,10 @@ timeout_t timeouts[] = {
 	{ { 0, 0 }, false, clear_resize },
 };
 
+cursor_t imgcursor[3] = {
+	CURSOR_ARROW, CURSOR_ARROW, CURSOR_ARROW
+};
+
 void cleanup(void)
 {
 	img_close(&img, false);
@@ -405,6 +409,14 @@ void update_info(void)
 	}
 }
 
+int ptr_third_x(void)
+{
+	int x, y;
+
+	win_cursor_pos(&win, &x, &y);
+	return MAX(0, MIN(2, (x / (win.w * 0.33))));
+}
+
 void redraw(void)
 {
 	int t;
@@ -428,14 +440,18 @@ void redraw(void)
 
 void reset_cursor(void)
 {
-	int i;
+	int c, i;
 	cursor_t cursor = CURSOR_NONE;
 
 	if (mode == MODE_IMAGE) {
 		for (i = 0; i < ARRLEN(timeouts); i++) {
 			if (timeouts[i].handler == reset_cursor) {
-				if (timeouts[i].active)
-					cursor = CURSOR_ARROW;
+				if (timeouts[i].active) {
+					c = ptr_third_x();
+					c = MAX(fileidx > 0 ? 0 : 1, c);
+					c = MIN(fileidx + 1 < filecnt ? 2 : 1, c);
+					cursor = imgcursor[c];
+				}
 				break;
 			}
 		}
@@ -872,6 +888,14 @@ int main(int argc, char **argv)
 	filecnt = fileidx;
 	fileidx = options->startnum < filecnt ? options->startnum : 0;
 
+	for (i = 0; i < ARRLEN(buttons); i++) {
+		if (buttons[i].cmd == i_cursor_navigate) {
+			imgcursor[0] = CURSOR_LEFT;
+			imgcursor[2] = CURSOR_RIGHT;
+			break;
+		}
+	}
+
 	win_init(&win);
 	img_init(&img, &win);
 	arl_init(&arl);
diff --git a/sxiv.1 b/sxiv.1
index bf738f8..e8cb04a 100644
--- a/sxiv.1
+++ b/sxiv.1
@@ -348,37 +348,27 @@ seconds.
 .SH MOUSE COMMANDS
 The following mouse mappings are available in image mode:
 .TP
+General:
+.TP
+.B Button3
 Navigate image list:
 .TP
 .B Button1
-Go to next image.
-.TP
-.B Button3
-Go to the previous image.
+Go to the next image if the mouse cursor is in the right part of the window or
+to the previous image if it is in the left part.
 .TP
 Panning:
 .TP
 .B Button2
-Drag the image with the mouse while keeping this button pressed down.
-.TP
-.B ScrollUp
-Scroll image up.
-.TP
-.B ScrollDown
-Scroll image down.
-.TP
-.B Shift+ScrollUp
-Scroll image left.
-.TP
-.B Shift+ScrollDown
-Scroll image right.
+Pan the image according to the mouse cursor position in the window while
+keeping this button pressed down.
 .TP
 Zooming:
 .TP
-.B Ctrl+ScrollUp
+.B ScrollUp
 Zoom in.
 .TP
-.B Ctrl+ScrollDown
+.B ScrollDown
 Zoom out.
 .SH STATUS BAR
 The information displayed on the left side of the status bar can be replaced
diff --git a/types.h b/types.h
index eacbd62..6c3fb3d 100644
--- a/types.h
+++ b/types.h
@@ -67,6 +67,8 @@ typedef enum {
 	CURSOR_ARROW,
 	CURSOR_DRAG,
 	CURSOR_WATCH,
+	CURSOR_LEFT,
+	CURSOR_RIGHT,
 	CURSOR_NONE,
 
 	CURSOR_COUNT
diff --git a/window.c b/window.c
index be2c9fa..463e52a 100644
--- a/window.c
+++ b/window.c
@@ -39,7 +39,8 @@ static struct {
 	int name;
 	Cursor icon;
 } cursors[CURSOR_COUNT] = {
-	{ XC_left_ptr }, { XC_dotbox }, { XC_watch }
+	{ XC_left_ptr }, { XC_dotbox }, { XC_watch },
+	{ XC_sb_left_arrow }, { XC_sb_right_arrow }
 };
 
 static GC gc;