Remap scroll wheel to LEFT/RIGHT for horizontal controls

The scroll wheel was always remapped to UP/DOWN, which is fine for
vertical lists but useless on horizontal controls like sliders and
the texture pack selector.

Track whether the mouse is hovering a horizontal control during the
hover hit-test (new bool m_bMouseHoverHorizontalList, set for
eTexturePackList and eSlider). When the flag is set, handleKeyPress
emits LEFT/RIGHT instead of UP/DOWN for wheel events.

TexturePackList is also now part of the mouse hover system with
proper hit-testing, relative-coord SetTouchFocus and GetRealHeight
for accurate bounds.

Minecraft.Client/Common/UI/UIController.cpp

@@ -3,6 +3,7 @@
 #include "UI.h"
 #include "UIScene.h"
 #include "UIControl_Slider.h"
+#include "UIControl_TexturePackList.h"
 #include "..\..\..\Minecraft.World\StringHelpers.h"
 #include "..\..\LocalPlayer.h"
 #include "..\..\DLCTexturePack.h"
@@ -238,6 +239,7 @@ UIController::UIController()
 	m_mouseDraggingSliderScene = eUIScene_COUNT;
 	m_mouseDraggingSliderId = -1;
 	m_mouseClickConsumedByScene = false;
+	m_bMouseHoverHorizontalList = false;
 	m_lastHoverMouseX = -1;
 	m_lastHoverMouseY = -1;
 	m_accumulatedTicks = 0;
@@ -856,6 +858,7 @@ void UIController::tickInput()
 					// use their own SetTouchFocus for Flash-side hit testing.
 					if (mouseMoved)
 					{
+						m_bMouseHoverHorizontalList = false;
 						vector<UIControl *> *controls = pScene->GetControls();
 						if (controls)
 						{
@@ -871,7 +874,7 @@ void UIController::tickInput()
 								UIControl::eUIControlType type = ctrl->getControlType();
 								if (type != UIControl::eButton && type != UIControl::eTextInput &&
 									type != UIControl::eCheckBox && type != UIControl::eSlider &&
-									type != UIControl::eButtonList)
+									type != UIControl::eButtonList && type != UIControl::eTexturePackList)
 									continue;
 
 								// If the scene has an active panel (e.g. tab menus),
@@ -884,6 +887,10 @@ void UIController::tickInput()
 								S32 cy = ctrl->getYPos() + panelOffsetY;
 								S32 cw = ctrl->getWidth();
 								S32 ch = ctrl->getHeight();
+								// TexturePackList origin is where the slot area starts,
+								// not the top-left of the whole control — use GetRealHeight.
+								if (type == UIControl::eTexturePackList)
+									ch = ((UIControl_TexturePackList *)ctrl)->GetRealHeight();
 								if (cw <= 0 || ch <= 0)
 									continue;
 
@@ -901,12 +908,27 @@ void UIController::tickInput()
 										hitCtrl = NULL;
 										break; // ButtonList takes priority
 									}
+									if (type == UIControl::eTexturePackList)
+									{
+										// TexturePackList expects coords relative to its origin.
+										UIControl_TexturePackList *pList = (UIControl_TexturePackList *)ctrl;
+										pScene->SetFocusToElement(ctrl->getId());
+										pList->SetTouchFocus(
+											(S32)(sceneMouseX - cx), (S32)(sceneMouseY - cy), false);
+										m_bMouseHoverHorizontalList = true;
+										hitControlId = -1;
+										hitArea = INT_MAX;
+										hitCtrl = NULL;
+										break;
+									}
 									S32 area = cw * ch;
 									if (area < hitArea)
 									{
 										hitControlId = ctrl->getId();
 										hitArea = area;
 										hitCtrl = ctrl;
+										if (type == UIControl::eSlider)
+											m_bMouseHoverHorizontalList = true;
 									}
 								}
 							}
@@ -1344,11 +1366,14 @@ void UIController::handleKeyPress(unsigned int iPad, unsigned int key)
 				down = true;
 			}
 
-			// Remap scroll wheel to UP/DOWN so all scenes get it without
+			// Remap scroll wheel to navigation actions. Use LEFT/RIGHT when
-			// needing per-scene OTHER_STICK handling.
+			// hovering a horizontal list (e.g. TexturePackList), UP/DOWN otherwise.
 			if (pressed && g_KBMInput.IsKBMActive())
 			{
-				key = (key == ACTION_MENU_OTHER_STICK_UP) ? ACTION_MENU_UP : ACTION_MENU_DOWN;
+				if (m_bMouseHoverHorizontalList)
+					key = (key == ACTION_MENU_OTHER_STICK_UP) ? ACTION_MENU_LEFT : ACTION_MENU_RIGHT;
+				else
+					key = (key == ACTION_MENU_OTHER_STICK_UP) ? ACTION_MENU_UP : ACTION_MENU_DOWN;
 			}
 		}
 	}

Minecraft.Client/Common/UI/UIController.h

@@ -161,6 +161,7 @@ private:
 	EUIScene m_mouseDraggingSliderScene;
 	int m_mouseDraggingSliderId;
 	bool m_mouseClickConsumedByScene;
+	bool m_bMouseHoverHorizontalList;
 	int m_lastHoverMouseX;
 	int m_lastHoverMouseY;
 	//bool m_bSysUIShowing;