From f6321e277bc423a0878ae239a73ad2cd6393106c Mon Sep 17 00:00:00 2001
From: sruz25 <sruz25cz@gmail.com>
Date: Fri, 19 Sep 2014 15:27:48 +0200
Subject: [PATCH] Add inventory right click drag and drop

---
 src/guiFormSpecMenu.cpp | 23 +++++++++++++++++++----
 src/guiFormSpecMenu.h   |  2 ++
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/src/guiFormSpecMenu.cpp b/src/guiFormSpecMenu.cpp
index 3fdb5bd26..65dbc0187 100644
--- a/src/guiFormSpecMenu.cpp
+++ b/src/guiFormSpecMenu.cpp
@@ -2950,9 +2950,11 @@ bool GUIFormSpecMenu::OnEvent(const SEvent& event)
 
 	}
 
-	if(event.EventType==EET_MOUSE_INPUT_EVENT
-			&& event.MouseInput.Event != EMIE_MOUSE_MOVED) {
-		// Mouse event other than movement
+	if((event.EventType==EET_MOUSE_INPUT_EVENT &&
+			event.MouseInput.Event != EMIE_MOUSE_MOVED) ||
+			(event.MouseInput.Event == EMIE_MOUSE_MOVED &&
+			event.MouseInput.isRightPressed() && getItemAtPos(m_pointer).i != getItemAtPos(m_old_pointer).i)){
+		// Mouse event other than movement or crossing the border of inventory field while holding rmb
 
 		// Get selected item and hovered/clicked item (s)
 
@@ -3008,7 +3010,7 @@ bool GUIFormSpecMenu::OnEvent(const SEvent& event)
 			(m_selected_item->i == s.i);
 
 		// buttons: 0 = left, 1 = right, 2 = middle
-		// up/down: 0 = down (press), 1 = up (release), 2 = unknown event
+		// up/down: 0 = down (press), 1 = up (release), 2 = unknown event, -1 movement
 		int button = 0;
 		int updown = 2;
 		if(event.MouseInput.Event == EMIE_LMOUSE_PRESSED_DOWN)
@@ -3023,6 +3025,8 @@ bool GUIFormSpecMenu::OnEvent(const SEvent& event)
 			{ button = 1; updown = 1; }
 		else if(event.MouseInput.Event == EMIE_MMOUSE_LEFT_UP)
 			{ button = 2; updown = 1; }
+		else if(event.MouseInput.Event == EMIE_MOUSE_MOVED)
+			{ updown = -1;}
 
 		// Set this number to a positive value to generate a move action
 		// from m_selected_item to s.
@@ -3113,6 +3117,16 @@ bool GUIFormSpecMenu::OnEvent(const SEvent& event)
 
 			m_selected_dragging = false;
 		}
+		else if(updown == -1) {
+			// Mouse has been moved and rmb is down and mouse pointer just
+			// entered a new inventory field (checked in the entry-if, this
+			// is the only action here that is generated by mouse movement)
+			if(m_selected_item != NULL && s.isValid()){
+				// Move 1 item
+				// TODO: middle mouse to move 10 items might be handy
+				move_amount = 1;
+			}
+		}
 
 		// Possibly send inventory action to server
 		if(move_amount > 0)
@@ -3212,6 +3226,7 @@ bool GUIFormSpecMenu::OnEvent(const SEvent& event)
 			m_selected_dragging = false;
 			m_selected_content_guess = ItemStack();
 		}
+		m_old_pointer = m_pointer;
 	}
 	if(event.EventType==EET_GUI_EVENT) {
 
diff --git a/src/guiFormSpecMenu.h b/src/guiFormSpecMenu.h
index 583cad4a2..2ffa05308 100644
--- a/src/guiFormSpecMenu.h
+++ b/src/guiFormSpecMenu.h
@@ -301,6 +301,7 @@ protected:
 	std::string m_formspec_string;
 	InventoryLocation m_current_inventory_location;
 
+
 	std::vector<ListDrawSpec> m_inventorylists;
 	std::vector<ImageDrawSpec> m_backgrounds;
 	std::vector<ImageDrawSpec> m_images;
@@ -323,6 +324,7 @@ protected:
 	InventoryLocation m_selected_content_guess_inventory;
 
 	v2s32 m_pointer;
+	v2s32 m_old_pointer;  // Mouse position after previous mouse event
 	gui::IGUIStaticText *m_tooltip_element;
 
 	u32 m_tooltip_show_delay;