GUI: Add scrolling

Fixes #107

source/client/app/Minecraft.cpp

@@ -420,6 +420,11 @@ void Minecraft::tickInput()
 		if (Mouse::isButtonDown(BUTTON_LEFT))
 			m_gui.handleClick(1, Mouse::getX(), Mouse::getY());
 
+#ifdef ENH_ALLOW_SCROLL_WHEEL
+		if (Mouse::getEventButton() == BUTTON_SCROLLWHEEL)
+			m_gui.handleScroll(Mouse::getEventButtonState() == 1);
+#endif
+
 		if (!bIsInGUI && getOptions()->field_19)
 		{
 			MouseButtonType buttonType = Mouse::getEventButton();
@@ -428,32 +433,6 @@ void Minecraft::tickInput()
 				handleMouseClick(buttonType);
 				field_DAC = field_DA8;
 			}
-
-#ifdef ENH_ALLOW_SCROLL_WHEEL
-			if (Mouse::getEventButton() == BUTTON_SCROLLWHEEL)
-			{
-				int slot = m_pLocalPlayer->m_pInventory->m_selectedHotbarSlot;
-
-				int maxItems = m_gui.getNumUsableSlots() - 1;
-
-				if (Mouse::getEventButtonState() == 0) // @NOTE: Scroll up
-				{
-					if (slot-- == 0)
-					{
-						slot = maxItems;
-					}
-				}
-				else
-				{
-					if (slot++ == maxItems) // @NOTE: Scroll down
-					{
-						slot = 0;
-					}
-				}
-
-				m_pLocalPlayer->m_pInventory->selectSlot(slot);
-			}
-#endif
 		}
 	}
 
@@ -1244,4 +1223,4 @@ void Minecraft::locateMultiplayer()
 	m_pRakNetInstance->pingForHosts(C_DEFAULT_PORT);
 	m_pNetEventCallback = new ClientSideNetworkHandler(this, m_pRakNetInstance);
 #endif
-}
+}

source/client/gui/Gui.cpp

@@ -446,6 +446,26 @@ void Gui::handleClick(int clickID, int mouseX, int mouseY)
 		m_pMinecraft->m_pLocalPlayer->m_pInventory->selectSlot(slot);
 }
 
+void Gui::handleScroll(bool down)
+{
+	int slot = m_pMinecraft->m_pLocalPlayer->m_pInventory->m_selectedHotbarSlot;
+
+	int maxItems = getNumUsableSlots() - 1;
+
+	if (down)
+	{
+		if (slot++ == maxItems)
+			slot = 0;
+	}
+	else
+	{
+		if (slot-- == 0)
+			slot = maxItems;
+	}
+
+	m_pMinecraft->m_pLocalPlayer->m_pInventory->selectSlot(slot);
+}
+
 void Gui::handleKeyPressed(int keyCode)
 {
 	if (m_pMinecraft->getOptions()->isKey(KM_INVENTORY, keyCode))
@@ -553,4 +573,4 @@ RectangleArea Gui::getRectangleArea(bool b)
 		Minecraft::height - 24.0f / InvGuiScale,
 		centerX + hotbarWidthHalf,
 		Minecraft::height);
-}
+}

source/client/gui/Gui.hpp

@@ -40,6 +40,7 @@ public:
 	int  getSlotIdAt(int mx, int my);
 	bool isInside(int mx, int my);
 	void handleClick(int id, int mx, int my);
+	void handleScroll(bool down);
 	void handleKeyPressed(int keyCode);
 	void renderMessages(bool bShowAll);
 	int getNumSlots();					  // Gets the number of slots in the inventory. Includes the '...' if in touch mode.

source/client/gui/Screen.cpp

@@ -120,6 +120,10 @@ void Screen::charInput(char chr)
 	}
 }
 
+void Screen::handleScroll(bool down)
+{
+}
+
 static const char* g_panoramaList[] =
 {
 	"gui/background/panorama_0.png",
@@ -430,6 +434,8 @@ void Screen::mouseEvent()
 		else
 			mouseReleased(m_width * pAction->_posX / Minecraft::width, m_height * pAction->_posY / Minecraft::height - 1 + getYOffset(), Mouse::getEventButton());
 	}
+	if (pAction->_buttonType == BUTTON_SCROLLWHEEL)
+		handleScroll(Mouse::getEventButtonState());
 }
 
 void Screen::renderBackground(int unk)

source/client/gui/Screen.hpp

@@ -48,6 +48,7 @@ public:
 	virtual void mouseReleased(int, int, int);
 	virtual void keyPressed(int);
 	virtual void charInput(char);
+	virtual void handleScroll(bool down);
 
 	// ported from 0.8
 	virtual void renderMenuBackground(float f);

source/client/gui/components/RolledSelectionList.cpp

@@ -335,3 +335,10 @@ void RolledSelectionList::clickedHeader(int x, int y)
 {
 
 }
+
+void RolledSelectionList::handleScroll(bool down)
+{
+	float diff = 5.0f * (down ? -1.0f : 1.0f);
+	field_34 = field_30 = field_30 + diff;
+	field_28 = 0;
+}

source/client/gui/components/RolledSelectionList.hpp

@@ -33,6 +33,7 @@ public:
 	virtual void renderBackground() = 0;
 	virtual void renderDecorations(int x, int y);
 	virtual void clickedHeader(int, int);
+	virtual void handleScroll(bool down);
 
 	int getItemAtXPositionRaw(int x);
 

source/client/gui/components/ScrolledSelectionList.cpp

@@ -97,7 +97,6 @@ void ScrolledSelectionList::renderScrollBackground()
 
 void ScrolledSelectionList::checkInput(int mouseX, int mouseY)
 {
-	int nItems = getNumberOfItems();
 	if (Mouse::isButtonDown(BUTTON_LEFT))
 	{
 		if (float(mouseY) >= field_C && float(mouseY) <= field_10 && abs(mouseY - field_28) > 5)
@@ -276,3 +275,10 @@ void ScrolledSelectionList::setRenderHeader(bool b, int i)
 		i = 0;
 	field_48 = i;
 }
+
+void ScrolledSelectionList::handleScroll(bool down)
+{
+	float diff = 5.0f * (down ? -1.0f : 1.0f);
+	field_34 -= diff;
+	field_38 += diff;
+}

source/client/gui/components/ScrolledSelectionList.hpp

@@ -36,6 +36,7 @@ public:
 	virtual void checkInput(int mouseX, int mouseY);
 	virtual void onClickItem(int index, int mouseX, int mouseY);
 	virtual void renderScrollBackground();
+	virtual void handleScroll(bool down);
 
 	void setRenderHeader(bool, int);
 

source/client/gui/screens/OptionsScreen.cpp

@@ -71,6 +71,10 @@ void OptionsScreen::buttonClicked(Button* pButton)
 	}
 }
 
+void OptionsScreen::handleScroll(bool down)
+{
+	m_pList->handleScroll(down);
+}
 
 #else
 

source/client/gui/screens/OptionsScreen.hpp

@@ -23,6 +23,7 @@ public:
 	void render(int, int, float) override;
 	void removed() override;
 	void buttonClicked(Button* pButton) override;
+	void handleScroll(bool down) override;
 
 private:
 	OptionList* m_pList;

source/client/gui/screens/SelectWorldScreen.cpp

@@ -222,6 +222,11 @@ void SelectWorldScreen::buttonClicked(Button* pButton)
 	}
 }
 
+void SelectWorldScreen::handleScroll(bool down)
+{
+	m_pWorldSelectionList->handleScroll(down);
+}
+
 bool SelectWorldScreen::isIndexValid(int idx)
 {
 	if (!m_pWorldSelectionList)

source/client/gui/screens/SelectWorldScreen.hpp

@@ -23,6 +23,7 @@ public:
 	void render(int mouseX, int mouseY, float f) override;
 	bool handleBackEvent(bool b) override;
 	void buttonClicked(Button* pButton) override;
+	void handleScroll(bool down) override;
 
 	bool isIndexValid(int);
 	std::string getUniqueLevelName(const std::string& in);