From 444bc4ae2e5800aefc66460703199218cdd0d8ec Mon Sep 17 00:00:00 2001
From: Parker Hawke <hawkeboyz2@hotmail.com>
Date: Mon, 31 Jul 2023 10:20:16 -0400
Subject: [PATCH] Add enhancement to support scroll wheel for inventory

---
 GameMods.hpp               |  1 +
 platforms/windows/main.cpp |  6 ++++++
 source/App/Minecraft.cpp   | 29 +++++++++++++++++++++++++++++
 3 files changed, 36 insertions(+)

diff --git a/GameMods.hpp b/GameMods.hpp
index cb0b48d..437e841 100644
--- a/GameMods.hpp
+++ b/GameMods.hpp
@@ -26,6 +26,7 @@
 #define ENH_HIGHLIGHT_BY_HOVER  // Highlight buttons by hovering them instead of the usual way.
 #define ENH_ALLOW_SAND_GRAVITY  // Allow sand to fall.
 #define ENH_USE_GUI_SCALE_2     // Use a 2x GUI scale instead of 3x. Looks better on PC
+#define ENH_ALLOW_SCROLL_WHEEL  // Allow use of the scroll wheel to change selected inventory slots
 
 // Mods
 //#define MOD_USE_FLAT_WORLD         // Use a flat world instead of the regular world generation
diff --git a/platforms/windows/main.cpp b/platforms/windows/main.cpp
index 1080525..ea86732 100644
--- a/platforms/windows/main.cpp
+++ b/platforms/windows/main.cpp
@@ -135,6 +135,12 @@ LRESULT CALLBACK WndProc(HWND hWnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
 
 			break;
 		}
+#ifdef ENH_ALLOW_SCROLL_WHEEL
+		case WM_MOUSEWHEEL:
+			Mouse::feed(3, GET_WHEEL_DELTA_WPARAM(wParam), g_MousePosX, g_MousePosY);
+
+			break;
+#endif
 		case WM_SIZE:
 		{
 			UINT width = LOWORD(lParam);
diff --git a/source/App/Minecraft.cpp b/source/App/Minecraft.cpp
index b4b9be7..b5d895f 100644
--- a/source/App/Minecraft.cpp
+++ b/source/App/Minecraft.cpp
@@ -341,6 +341,35 @@ void Minecraft::tickInput()
 				handleMouseClick(2);
 				field_DAC = field_DA8;
 			}
+#ifdef ENH_ALLOW_SCROLL_WHEEL
+			if (input.field_0 == 3)
+			{
+				int slot = m_pLocalPlayer->m_pInventory->m_SelectedHotbarSlot;
+
+#ifdef ENH_ENABLE_9TH_SLOT
+#define MAX_ITEMS (C_MAX_HOTBAR_ITEMS - 1)
+#else
+#define MAX_ITEMS (C_MAX_HOTBAR_ITEMS - 2)
+#endif
+
+				if (input.field_4 > 0) // @NOTE: Scroll up
+				{
+					if (slot-- == 0)
+					{
+						slot = MAX_ITEMS;
+					}
+				}
+				else
+				{
+					if (slot++ == MAX_ITEMS) // @NOTE: Scroll down
+					{
+						slot = 0;
+					}
+				}
+
+				m_pLocalPlayer->m_pInventory->selectSlot(slot);
+			}
+#endif
 		}
 
 	}