Refactored setting UI element style.

All UI elements derived from BorderImage can now define different graphics to be used on hover.
UI layout loading support.

Bin/Data/UI/UI.xml → Bin/Data/UI/DefaultStyle.xml

@@ -1,21 +1,20 @@
 <elements>
-    <element name="Cursor">
+    <element type="Cursor">
         <size value="16 24" />
         <texture name="Textures/UI.png" />
         <imagerect value="0 0 16 24" />
         <hotspot value="0 0" />
     </element>
-    <element name="Button">
+    <element type="Button">
         <size value="16 16" />
         <texture name="Textures/UI.png" />
-        <color value="0.85 0.85 0.85" />
-        <hovercolor value="0.15 0.15 0.15" />
         <inactiverect value="16 0 32 16" />
         <pressedrect value="32 0 48 16" />
         <border value="4 4 4 4" />
+        <hoveroffset value="0 16" />
         <labeloffset value="-1 1" />
     </element>
-    <element name="Window">
+    <element type="Window">
         <texture name="Textures/UI.png" />
         <imagerect value="48 0 64 16" />
         <border value="3 3 3 3" />
@@ -23,16 +22,15 @@
         <movable enable="true" />
         <resizable enable="true" />
     </element>
-    <element name="Text">
+    <element type="Text">
         <font name="Cour.ttf" size="10" />
     </element>
-    <element name="CheckBox">
+    <element type="CheckBox">
         <size value="16 16" />
         <texture name="Textures/UI.png" />
-        <color value="0.85 0.85 0.85" />
-        <hovercolor value="0.15 0.15 0.15" />
         <uncheckedrect value="64 0 80 16" />
         <checkedrect value="80 0 96 16" />
         <border value="4 4 4 4" />
+        <hoveroffset value="0 16" />
     </element>
 </elements>

Bin/Data/UI/TestLayout.xml

@@ -0,0 +1,11 @@
+<layout>
+    <element type="Button">
+        <size value="100 40" />
+        <alignment horizontal="center" vertical="center" />
+        <element type="Text">
+            <text value="TEST" />
+            <font name="cour.ttf" size="12" />
+            <alignment horizontal="center" vertical="center" />
+        </element>
+    </element>
+</layout>

Engine/Engine/RegisterTemplates.h

@@ -27,6 +27,7 @@
 #include "BorderImage.h"
 #include "Channel.h"
 #include "Deserializer.h"
+#include "Engine.h"
 #include "GeometryNode.h"
 #include "RegisterArray.h"
 #include "Resource.h"
@@ -331,17 +332,43 @@ template <class T> T* ConstructUIElementWithName(const std::string& name)
     return new T(name);
 }
 
+//! Template function for setting UI element style from an XML element
+template <class T> void UIElementSetStyle(const XMLElement& element, T* ptr)
+{
+    try
+    {
+        ptr->setStyle(element, getEngine()->getResourceCache());
+    }
+    catch (Exception& e)
+    {
+        SAFE_RETHROW(e);
+    }
+}
+
+//! Template function for setting UI element style from an XML file
+template <class T> void UIElementSetStyleAuto(XMLFile* file, T* ptr)
+{
+    try
+    {
+        ptr->setStyleAuto(file, getEngine()->getResourceCache());
+    }
+    catch (Exception& e)
+    {
+        SAFE_RETHROW(e);
+    }
+}
+
 //! Template function for registering a class derived from UIElement
 template <class T> void registerUIElement(asIScriptEngine* engine, const char* className)
 {
     static const std::string declFactory(std::string(className) + "@+ f()");
     static const std::string declFactoryWithName(std::string(className) + "@+ f(const string& in)");
     
-    engine->RegisterObjectType(className, 0, asOBJ_REF);
+    registerHashedType<T>(engine, className);
     engine->RegisterObjectBehaviour(className, asBEHAVE_FACTORY, declFactory.c_str(), asFUNCTION(ConstructUIElement<T>), asCALL_CDECL);
     engine->RegisterObjectBehaviour(className, asBEHAVE_FACTORY, declFactoryWithName.c_str(), asFUNCTION(ConstructUIElementWithName<T>), asCALL_CDECL);
-    engine->RegisterObjectBehaviour(className, asBEHAVE_ADDREF, "void f()", asMETHODPR(T, addRef, (), void), asCALL_THISCALL);
-    engine->RegisterObjectBehaviour(className, asBEHAVE_RELEASE, "void f()", asMETHODPR(T, releaseRef, (), void), asCALL_THISCALL);
+    engine->RegisterObjectMethod(className, "void setStyle(const XMLElement& in)", asFUNCTION(UIElementSetStyle<T>), asCALL_CDECL_OBJLAST);
+    engine->RegisterObjectMethod(className, "void setStyleAuto(XMLFile@+)", asFUNCTION(UIElementSetStyleAuto<T>), asCALL_CDECL_OBJLAST);
     engine->RegisterObjectMethod(className, "void setName(const string& in)", asMETHOD(T, setName), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "void setPosition(const IntVector2& in)", asMETHODPR(T, setPosition, (const IntVector2&), void), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "void setPosition(int, int)", asMETHODPR(T, setPosition, (int, int), void), asCALL_THISCALL);
@@ -371,6 +398,7 @@ template <class T> void registerUIElement(asIScriptEngine* engine, const char* c
     engine->RegisterObjectMethod(className, "const IntVector2& getSize() const", asMETHOD(T, getSize), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "int getWidth() const", asMETHOD(T, getWidth), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "int getHeight() const", asMETHOD(T, getHeight), asCALL_THISCALL);
+    engine->RegisterObjectMethod(className, "const IntVector2& getChildOffset() const", asMETHOD(T, getChildOffset), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "HorizontalAlignment getHorizontalAlignment() const", asMETHOD(T, getHorizontalAlignment), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "VerticalAlignment getVerticalAlignment() const", asMETHOD(T, getVerticalAlignment), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "const Color& getColor(UIElementCorner) const", asMETHOD(T, getColor), asCALL_THISCALL);
@@ -389,6 +417,7 @@ template <class T> void registerUIElement(asIScriptEngine* engine, const char* c
     engine->RegisterObjectMethod(className, "UIElement@+ getChild(uint) const", asMETHODPR(T, getChild, (unsigned) const, UIElement*), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "UIElement@+ getChild(const string& in, bool) const", asMETHODPR(T, getChild, (const std::string&, bool) const, UIElement*), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "UIElement@+ getParent() const", asMETHOD(T, getParent), asCALL_THISCALL);
+    engine->RegisterObjectMethod(className, "XMLElement getStyleElement(XMLFile@+) const", asMETHODPR(T, getStyleElement, (XMLFile*) const, XMLElement), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "IntVector2 screenToElement(const IntVector2& in)", asMETHOD(T, screenToElement), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "IntVector2 elementToScreen(const IntVector2& in)", asMETHOD(T, elementToScreen), asCALL_THISCALL);
 }
@@ -403,9 +432,12 @@ template <class T> void registerBorderImage(asIScriptEngine* engine, const char*
     engine->RegisterObjectMethod(className, "void setFullImageRect()", asMETHOD(T, setFullImageRect), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "void setBorder(const IntRect& in)", asMETHODPR(T, setBorder, (const IntRect&), void), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "void setBorder(int, int, int, int)", asMETHODPR(T, setBorder, (int, int, int, int), void), asCALL_THISCALL);
+    engine->RegisterObjectMethod(className, "void setHoverOffset(const IntVector2& in)", asMETHODPR(T, setHoverOffset, (const IntVector2&), void), asCALL_THISCALL);
+    engine->RegisterObjectMethod(className, "void setHoverOffset(int, int)", asMETHODPR(T, setHoverOffset, (int, int), void), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "Texture@+ getTexture() const", asMETHOD(T, setTexture), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "const IntRect& getImageRect() const", asMETHOD(T, getImageRect), asCALL_THISCALL);
     engine->RegisterObjectMethod(className, "const IntRect& getBorder() const", asMETHOD(T, getBorder), asCALL_THISCALL);
+    engine->RegisterObjectMethod(className, "const IntVector2& getHoverOffset() const", asMETHOD(T, getHoverOffset), asCALL_THISCALL);
 }
 
 #endif // ENGINE_REGISTERTEMPLATES_H

Engine/Engine/RegisterUI.cpp

@@ -38,18 +38,6 @@ static void registerFont(asIScriptEngine* engine)
     registerRefCasts<Resource, Font>(engine, "Resource", "Font");
 }
 
-void UIElementLoadParameters(XMLFile* file, const std::string& elementName, UIElement* ptr)
-{
-    try
-    {
-        ptr->loadParameters(file, elementName, getEngine()->getResourceCache());
-    }
-    catch (Exception& e)
-    {
-        SAFE_RETHROW(e);
-    }
-}
-
 static void registerUIElement(asIScriptEngine* engine)
 {
     engine->RegisterEnum("HorizontalAlignment");
@@ -69,7 +57,9 @@ static void registerUIElement(asIScriptEngine* engine)
     engine->RegisterEnumValue("UIElementCorner", "C_BOTTOMRIGHT", C_BOTTOMRIGHT);
     
     registerUIElement<UIElement>(engine, "UIElement");
-    engine->RegisterObjectMethod("UIElement", "void loadParameters(XMLFile@+, const string& in)", asFUNCTION(UIElementLoadParameters), asCALL_CDECL_OBJLAST);
+    
+    // Register static function for getting UI style XML element
+    engine->RegisterGlobalFunction("XMLElement getStyleElement(XMLFile@+, const string& in)", asFUNCTIONPR(UIElement::getStyleElement, (XMLFile*, const std::string&), XMLElement), asCALL_CDECL);
     
     // Register Variant getPtr() for UIElement
     engine->RegisterObjectMethod("Variant", "UIElement@+ getUIElement() const", asFUNCTION(getVariantPtr<UIElement>), asCALL_CDECL_OBJLAST);
@@ -78,7 +68,6 @@ static void registerUIElement(asIScriptEngine* engine)
 static void registerText(asIScriptEngine* engine)
 {
     registerUIElement<Text>(engine, "Text");
-    engine->RegisterObjectMethod("Text", "void loadParameters(XMLFile@+, const string& in)", asFUNCTION(UIElementLoadParameters), asCALL_CDECL_OBJLAST);
     engine->RegisterObjectMethod("Text", "bool setFont(Font@+, int)", asMETHOD(Text, setFont), asCALL_THISCALL);
     engine->RegisterObjectMethod("Text", "void setMaxWidth(int)", asMETHOD(Text, setMaxWidth), asCALL_THISCALL);
     engine->RegisterObjectMethod("Text", "void setText(const string& in)", asMETHOD(Text, setText), asCALL_THISCALL);
@@ -98,14 +87,12 @@ static void registerText(asIScriptEngine* engine)
 static void registerBorderImage(asIScriptEngine* engine)
 {
     registerBorderImage<BorderImage>(engine, "BorderImage");
-    engine->RegisterObjectMethod("BorderImage", "void loadParameters(XMLFile@+, const string& in)", asFUNCTION(UIElementLoadParameters), asCALL_CDECL_OBJLAST);
     registerRefCasts<UIElement, BorderImage>(engine, "UIElement", "BorderImage");
 }
 
 static void registerCursor(asIScriptEngine* engine)
 {
     registerBorderImage<Cursor>(engine, "Cursor");
-    engine->RegisterObjectMethod("Cursor", "void loadParameters(XMLFile@+, const string& in)", asFUNCTION(UIElementLoadParameters), asCALL_CDECL_OBJLAST);
     engine->RegisterObjectMethod("Cursor", "void setHotspot(const IntVector2& in)", asMETHODPR(Cursor, setHotspot, (const IntVector2&), void), asCALL_THISCALL);
     engine->RegisterObjectMethod("Cursor", "void setHotspot(int, int)", asMETHODPR(Cursor, setHotspot, (int, int), void), asCALL_THISCALL);
     engine->RegisterObjectMethod("Cursor", "const IntVector2& getHotspot() const", asMETHOD(Cursor, getHotspot), asCALL_THISCALL);
@@ -115,17 +102,14 @@ static void registerCursor(asIScriptEngine* engine)
 static void registerButton(asIScriptEngine* engine)
 {
     registerBorderImage<Button>(engine, "Button");
-    engine->RegisterObjectMethod("Button", "void loadParameters(XMLFile@+, const string& in)", asFUNCTION(UIElementLoadParameters), asCALL_CDECL_OBJLAST);
     engine->RegisterObjectMethod("Button", "void setInactiveRect(const IntRect& in)", asMETHODPR(Button, setInactiveRect, (const IntRect&), void), asCALL_THISCALL);
     engine->RegisterObjectMethod("Button", "void setInactiveRect(int, int, int, int)", asMETHODPR(Button, setInactiveRect, (int, int, int, int), void), asCALL_THISCALL);
     engine->RegisterObjectMethod("Button", "void setPressedRect(const IntRect& in)", asMETHODPR(Button, setPressedRect, (const IntRect&), void), asCALL_THISCALL);
     engine->RegisterObjectMethod("Button", "void setPressedRect(int, int, int, int)", asMETHODPR(Button, setPressedRect, (int, int, int, int), void), asCALL_THISCALL);
-    engine->RegisterObjectMethod("Button", "void setLabel(UIElement@+)", asMETHOD(Button, setLabel), asCALL_THISCALL);
     engine->RegisterObjectMethod("Button", "void setLabelOffset(const IntVector2& in)", asMETHODPR(Button, setLabelOffset, (const IntVector2&), void), asCALL_THISCALL);
     engine->RegisterObjectMethod("Button", "void setLabelOffset(int, int)", asMETHODPR(Button, setLabelOffset, (int, int), void), asCALL_THISCALL);
     engine->RegisterObjectMethod("Button", "const IntRect& getInactiveRect() const", asMETHOD(Button, getInactiveRect), asCALL_THISCALL);
     engine->RegisterObjectMethod("Button", "const IntRect& getPressedRect() const", asMETHOD(Button, getPressedRect), asCALL_THISCALL);
-    engine->RegisterObjectMethod("Button", "UIElement@+ getLabel() const", asMETHOD(Button, getLabel), asCALL_THISCALL);
     engine->RegisterObjectMethod("Button", "const IntVector2& getLabelOffset() const", asMETHOD(Button, getLabelOffset), asCALL_THISCALL);
     registerRefCasts<UIElement, Button>(engine, "UIElement", "Button");
 }
@@ -133,7 +117,6 @@ static void registerButton(asIScriptEngine* engine)
 static void registerCheckBox(asIScriptEngine* engine)
 {
     registerBorderImage<CheckBox>(engine, "CheckBox");
-    engine->RegisterObjectMethod("CheckBox", "void loadParameters(XMLFile@+, const string& in)", asFUNCTION(UIElementLoadParameters), asCALL_CDECL_OBJLAST);
     engine->RegisterObjectMethod("CheckBox", "void setChecked(bool)", asMETHOD(CheckBox, setChecked), asCALL_THISCALL);
     engine->RegisterObjectMethod("CheckBox", "void setUncheckedRect(const IntRect& in)", asMETHODPR(CheckBox, setUncheckedRect, (const IntRect&), void), asCALL_THISCALL);
     engine->RegisterObjectMethod("CheckBox", "void setUncheckedRect(int, int, int, int)", asMETHODPR(CheckBox, setUncheckedRect, (int, int, int, int), void), asCALL_THISCALL);
@@ -148,7 +131,6 @@ static void registerCheckBox(asIScriptEngine* engine)
 static void registerWindow(asIScriptEngine* engine)
 {
     registerBorderImage<Window>(engine, "Window");
-    engine->RegisterObjectMethod("Window", "void loadParameters(XMLFile@+, const string& in)", asFUNCTION(UIElementLoadParameters), asCALL_CDECL_OBJLAST);
     engine->RegisterObjectMethod("Window", "void setMovable(bool)", asMETHOD(Window, setMovable), asCALL_THISCALL);
     engine->RegisterObjectMethod("Window", "void setResizable(bool)", asMETHOD(Window, setResizable), asCALL_THISCALL);
     engine->RegisterObjectMethod("Window", "void setMinSize(const IntVector2& in)", asMETHODPR(Window, setMinSize, (const IntVector2&), void), asCALL_THISCALL);
@@ -180,6 +162,53 @@ static Cursor* GetUICursor()
     return getEngine()->getUICursor();
 }
 
+static UIElement* UICreateElement(const std::string& type, const std::string& name, UI* ptr)
+{
+    try
+    {
+        SharedPtr<UIElement> element = ptr->createElement(ShortStringHash(type), name);
+        // The shared pointer will go out of scope, so have to increment the reference count
+        // (here an auto handle can not be used)
+        if (element)
+            element->addRef();
+        return element.getPtr();
+    }
+    catch (Exception& e)
+    {
+        SAFE_RETHROW_RET(e, 0);
+    }
+}
+
+static UIElement* UILoadLayout(XMLFile* file, UI* ptr)
+{
+    try
+    {
+        SharedPtr<UIElement> root = ptr->loadLayout(file);
+        if (root)
+            root->addRef();
+        return root.getPtr();
+    }
+    catch (Exception& e)
+    {
+        SAFE_RETHROW_RET(e, 0);
+    }
+}
+
+static UIElement* UILoadLayoutWithStyle(XMLFile* file, XMLFile* styleFile, UI* ptr)
+{
+    try
+    {
+        SharedPtr<UIElement> root = ptr->loadLayout(file, styleFile);
+        if (root)
+            root->addRef();
+        return root.getPtr();
+    }
+    catch (Exception& e)
+    {
+        SAFE_RETHROW_RET(e, 0);
+    }
+}
+
 static void registerUI(asIScriptEngine* engine)
 {
     engine->RegisterObjectType("UI", 0, asOBJ_REF);
@@ -188,6 +217,9 @@ static void registerUI(asIScriptEngine* engine)
     engine->RegisterObjectMethod("UI", "void setCursor(Cursor@+)", asMETHOD(UI, setCursor), asCALL_THISCALL);
     engine->RegisterObjectMethod("UI", "void setFocusElement(UIElement@+)", asMETHOD(UI, setFocusElement), asCALL_THISCALL);
     engine->RegisterObjectMethod("UI", "void bringToFront(UIElement@+)", asMETHOD(UI, bringToFront), asCALL_THISCALL);
+    engine->RegisterObjectMethod("UI", "UIElement@ createElement(const string& in, const string& in)", asFUNCTION(UICreateElement), asCALL_CDECL_OBJLAST);
+    engine->RegisterObjectMethod("UI", "UIElement@ loadLayout(XMLFile@+)", asFUNCTION(UILoadLayout), asCALL_CDECL_OBJLAST);
+    engine->RegisterObjectMethod("UI", "UIElement@ loadLayout(XMLFile@+, XMLFile@+)", asFUNCTION(UILoadLayoutWithStyle), asCALL_CDECL_OBJLAST);
     engine->RegisterObjectMethod("UI", "UIElement@+ getRootElement() const", asMETHOD(UI, getRootElement), asCALL_THISCALL);
     engine->RegisterObjectMethod("UI", "Cursor@+ getCursor() const", asMETHOD(UI, getCursor), asCALL_THISCALL);
     engine->RegisterObjectMethod("UI", "UIElement@+ getElementAt(const IntVector2& in, bool)", asMETHODPR(UI, getElementAt, (const IntVector2&, bool), UIElement*), asCALL_THISCALL);

Engine/Renderer/Renderer.cpp

@@ -1476,7 +1476,7 @@ void Renderer::setScissorTest(bool enable, const Rect& rect, bool borderInclusiv
         }
     }
     else
-        mScissorRect = IntRect(0, 0, 0, 0);
+        mScissorRect = IntRect::sZero;
     
     if (enable != mScissorTest)
     {
@@ -1528,7 +1528,7 @@ void Renderer::setScissorTest(bool enable, const IntRect& rect)
         }
     }
     else
-        mScissorRect = IntRect(0, 0, 0, 0);
+        mScissorRect = IntRect::sZero;
     
     if (enable != mScissorTest)
     {
@@ -2182,7 +2182,7 @@ void Renderer::resetCachedState()
     mDepthWrite = true;
     mFillMode = FILL_SOLID;
     mScissorTest = false;
-    mScissorRect = IntRect(0, 0, 0, 0);
+    mScissorRect = IntRect::sZero;
     mStencilTest = false;
     mStencilTestMode = CMP_ALWAYS;
     mStencilPass = OP_KEEP;

Engine/UI/BaseUIElementFactory.cpp

@@ -0,0 +1,50 @@
+//
+// Urho3D Engine
+// Copyright (c) 2008-2011 Lasse Öörni
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+#include "Precompiled.h"
+#include "BaseUIElementFactory.h"
+#include "Button.h"
+#include "CheckBox.h"
+#include "Cursor.h"
+#include "Text.h"
+#include "Window.h"
+
+UIElement* BaseUIElementFactory::createElement(ShortStringHash type, const std::string& name)
+{
+    if (type == BorderImage::getTypeStatic())
+        return new BorderImage(name);
+    if (type == Button::getTypeStatic())
+        return new Button(name);
+    if (type == CheckBox::getTypeStatic())
+        return new CheckBox(name);
+    if (type == Cursor::getTypeStatic())
+        return new Cursor(name);
+    if (type == Text::getTypeStatic())
+        return new Text(std::string(), name);
+    if (type == UIElement::getTypeStatic())
+        return new UIElement(name);
+    if (type == Window::getTypeStatic())
+        return new Window(name);
+    
+    return 0;
+}

Engine/UI/BaseUIElementFactory.h

@@ -0,0 +1,37 @@
+//
+// Urho3D Engine
+// Copyright (c) 2008-2011 Lasse Öörni
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+#ifndef UI_BASEUIELEMENTFACTORY_H
+#define UI_BASEUIELEMENTFACTORY_H
+
+#include "UIElementFactory.h"
+
+//! Creates the inbuilt UI elements
+class BaseUIElementFactory : public UIElementFactory
+{
+public:
+    //! Create a UI element of the specified type. Return null if can not create
+    virtual UIElement* createElement(ShortStringHash type, const std::string& name = std::string());
+};
+
+#endif // UI_BASEUIELEMENTFACTORY_H

Engine/UI/BorderImage.cpp

@@ -30,8 +30,9 @@
 
 BorderImage::BorderImage(const std::string& name) :
     UIElement(name),
-    mImageRect(0, 0, 0, 0),
-    mBorder(0, 0, 0, 0)
+    mImageRect(IntRect::sZero),
+    mBorder(IntRect::sZero),
+    mHoverOffset(IntVector2::sZero)
 {
 }
 
@@ -39,18 +40,21 @@ BorderImage::~BorderImage()
 {
 }
 
-XMLElement BorderImage::loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache)
+void BorderImage::setStyle(const XMLElement& element, ResourceCache* cache)
 {
-    XMLElement paramElem = UIElement::loadParameters(file, elementName, cache);
+    if (!cache)
+        SAFE_EXCEPTION("Null resource cache for UI element");
     
-    if (paramElem.hasChildElement("texture"))
-        setTexture(cache->getResource<Texture2D>(paramElem.getChildElement("texture").getString("name")));
-    if (paramElem.hasChildElement("imagerect"))
-        setImageRect(paramElem.getChildElement("imagerect").getIntRect("value"));
-    if (paramElem.hasChildElement("border"))
-        setBorder(paramElem.getChildElement("border").getIntRect("value"));
+    UIElement::setStyle(element, cache);
     
-    return paramElem;
+    if (element.hasChildElement("texture"))
+        setTexture(cache->getResource<Texture2D>(element.getChildElement("texture").getString("name")));
+    if (element.hasChildElement("imagerect"))
+        setImageRect(element.getChildElement("imagerect").getIntRect("value"));
+    if (element.hasChildElement("border"))
+        setBorder(element.getChildElement("border").getIntRect("value"));
+    if (element.hasChildElement("hoveroffset"))
+        setHoverOffset(element.getChildElement("hoveroffset").getIntVector2("value"));
 }
 
 void BorderImage::getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>& quads, const IntRect& currentScissor)
@@ -69,31 +73,35 @@ void BorderImage::getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>&
     IntVector2 innerTextureSize(
         max(mImageRect.mRight - mImageRect.mLeft - mBorder.mLeft - mBorder.mRight, 0),
         max(mImageRect.mBottom - mImageRect.mTop - mBorder.mTop - mBorder.mBottom, 0));
-
+    
+    IntVector2 topLeft(mImageRect.mLeft, mImageRect.mTop);
+    if (mHovering)
+        topLeft += mHoverOffset;
+    
     // Top
     if (mBorder.mTop)
     {
         if (mBorder.mLeft)
-            batch.addQuad(*this, 0, 0, mBorder.mLeft, mBorder.mTop, mImageRect.mLeft, mImageRect.mTop);
+            batch.addQuad(*this, 0, 0, mBorder.mLeft, mBorder.mTop, topLeft.mX, topLeft.mY);
         if (innerSize.mX)
             batch.addQuad(*this, mBorder.mLeft, 0, innerSize.mX, mBorder.mTop,
-            mImageRect.mLeft + mBorder.mLeft, mImageRect.mTop, innerTextureSize.mX, mBorder.mTop);
+            topLeft.mX + mBorder.mLeft, topLeft.mY, innerTextureSize.mX, mBorder.mTop);
         if (mBorder.mRight)
             batch.addQuad(*this, mBorder.mLeft + innerSize.mX, 0, mBorder.mRight, mBorder.mTop,
-            mImageRect.mLeft + mBorder.mLeft + innerTextureSize.mX, mImageRect.mTop);
+            topLeft.mX + mBorder.mLeft + innerTextureSize.mX, topLeft.mY);
     }
     // Middle
     if (innerSize.mY)
     {
         if (mBorder.mLeft)
             batch.addQuad(*this, 0, mBorder.mTop, mBorder.mLeft, innerSize.mY,
-            mImageRect.mLeft, mImageRect.mTop + mBorder.mTop, mBorder.mLeft, innerTextureSize.mY);
+            topLeft.mX, topLeft.mY + mBorder.mTop, mBorder.mLeft, innerTextureSize.mY);
         if (innerSize.mX)
             batch.addQuad(*this, mBorder.mLeft, mBorder.mTop, innerSize.mX, innerSize.mY,
-            mImageRect.mLeft + mBorder.mLeft, mImageRect.mTop + mBorder.mTop, innerTextureSize.mX, innerTextureSize.mY);
+            topLeft.mX + mBorder.mLeft, topLeft.mY + mBorder.mTop, innerTextureSize.mX, innerTextureSize.mY);
         if (mBorder.mRight)
             batch.addQuad(*this, mBorder.mLeft + innerSize.mX, mBorder.mTop, mBorder.mRight,
-            innerSize.mY, mImageRect.mLeft + mBorder.mLeft + innerTextureSize.mX, mImageRect.mTop + mBorder.mTop,
+            innerSize.mY, topLeft.mX + mBorder.mLeft + innerTextureSize.mX, topLeft.mY + mBorder.mTop,
             mBorder.mRight, innerTextureSize.mY);
     }
     // Bottom
@@ -101,18 +109,21 @@ void BorderImage::getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>&
     {
         if (mBorder.mLeft)
             batch.addQuad(*this, 0, mBorder.mTop + innerSize.mY, mBorder.mLeft, mBorder.mBottom,
-            mImageRect.mLeft, mImageRect.mTop + mBorder.mTop + innerTextureSize.mY);
+            topLeft.mX, topLeft.mY + mBorder.mTop + innerTextureSize.mY);
         if (innerSize.mX)
             batch.addQuad(*this, mBorder.mLeft, mBorder.mTop + innerSize.mY, innerSize.mX,
-            mBorder.mBottom, mImageRect.mLeft + mBorder.mLeft, mImageRect.mTop + mBorder.mTop + innerTextureSize.mY,
+            mBorder.mBottom, topLeft.mX + mBorder.mLeft, topLeft.mY + mBorder.mTop + innerTextureSize.mY,
             innerTextureSize.mX, mBorder.mBottom);
         if (mBorder.mRight)
             batch.addQuad(*this, mBorder.mLeft + innerSize.mX, mBorder.mTop + innerSize.mY,
-            mBorder.mRight, mBorder.mBottom, mImageRect.mLeft + mBorder.mLeft + innerTextureSize.mX, 
-            mImageRect.mTop + mBorder.mTop + innerTextureSize.mY);
+            mBorder.mRight, mBorder.mBottom, topLeft.mX + mBorder.mLeft + innerTextureSize.mX, 
+            topLeft.mY + mBorder.mTop + innerTextureSize.mY);
     }
     
     UIBatch::addOrMerge(batch, batches);
+    
+    // Reset hovering for next frame
+    mHovering = false;
 }
 
 void BorderImage::setTexture(Texture* texture)
@@ -161,3 +172,13 @@ void BorderImage::setBorder(int left, int top, int right, int bottom)
     mBorder.mRight = max(right, 0);
     mBorder.mBottom = max(bottom, 0);
 }
+
+void BorderImage::setHoverOffset(const IntVector2& offset)
+{
+    mHoverOffset = offset;
+}
+
+void BorderImage::setHoverOffset(int x, int y)
+{
+    mHoverOffset = IntVector2(x, y);
+}

Engine/UI/BorderImage.h

@@ -32,14 +32,16 @@ class Texture2D;
 //! An UI element with an image that optionally has a border
 class BorderImage : public UIElement
 {
+    DEFINE_TYPE(BorderImage);
+    
 public:
     //! Construct with name
     BorderImage(const std::string& name = std::string());
     //! Destruct
     virtual ~BorderImage();
     
-    //! Load parameters from an XML file
-    virtual XMLElement loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache);
+    //! Set UI element style from XML data
+    virtual void setStyle(const XMLElement& element, ResourceCache* cache);
     //! Return UI rendering batches
     virtual void getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>& quads, const IntRect& currentScissor);
     
@@ -55,6 +57,10 @@ public:
     void setBorder(const IntRect& rect);
     //! Set image border dimensions
     void setBorder(int left, int top, int right, int bottom);
+    //! Set offset to image rectangle used on hover
+    void setHoverOffset(const IntVector2& offset);
+    //! Set offset to image rectangle used on hover
+    void setHoverOffset(int x, int y);
     
     //! Return texture
     Texture* getTexture() const { return mTexture; }
@@ -62,6 +68,8 @@ public:
     const IntRect& getImageRect() const { return mImageRect; }
     //! Return image border dimensions
     const IntRect& getBorder() const { return mBorder; }
+    //! Return offset to image rectangle used on hover
+    const IntVector2& getHoverOffset() const { return mHoverOffset; }
     
 protected:
     //! Texture
@@ -70,6 +78,8 @@ protected:
     IntRect mImageRect;
     //! Image border dimensions
     IntRect mBorder;
+    //! Offset to image rectangle on hover
+    IntVector2 mHoverOffset;
 };
 
 #endif // UI_BORDERIMAGE_H

Engine/UI/Button.cpp

@@ -32,56 +32,48 @@
 
 Button::Button(const std::string& name) :
     BorderImage(name),
-    mInactiveRect(0, 0, 0, 0),
-    mPressedRect(0, 0, 0, 0),
-    mLabelOffset(0, 0),
+    mInactiveRect(IntRect::sZero),
+    mPressedRect(IntRect::sZero),
+    mLabelOffset(IntVector2::sZero),
     mPressed(false)
 {
     mClipChildren = true;
     mEnabled = true;
-    mLabelContainer = new UIElement();
-    addChild(mLabelContainer);
 }
 
 Button::~Button()
 {
 }
 
-XMLElement Button::loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache)
+void Button::setStyle(const XMLElement& element, ResourceCache* cache)
 {
-    XMLElement paramElem = BorderImage::loadParameters(file, elementName, cache);
+    if (!cache)
+        SAFE_EXCEPTION("Null resource cache for UI element");
     
-    if (paramElem.hasChildElement("inactiverect"))
-        setInactiveRect(paramElem.getChildElement("inactiverect").getIntRect("value"));
-    if (paramElem.hasChildElement("pressedrect"))
-        setPressedRect(paramElem.getChildElement("pressedrect").getIntRect("value"));
-    if (paramElem.hasChildElement("labeloffset"))
-        setLabelOffset(paramElem.getChildElement("labeloffset").getIntVector2("value"));
+    BorderImage::setStyle(element, cache);
     
-    return paramElem;
+    if (element.hasChildElement("inactiverect"))
+        setInactiveRect(element.getChildElement("inactiverect").getIntRect("value"));
+    if (element.hasChildElement("pressedrect"))
+        setPressedRect(element.getChildElement("pressedrect").getIntRect("value"));
+    if (element.hasChildElement("labeloffset"))
+        setLabelOffset(element.getChildElement("labeloffset").getIntVector2("value"));
 }
 
 void Button::update(float timeStep)
 {
     if (!mHovering)
         setPressed(false);
-    
-    if (mLabelContainer->getSize() != getSize())
-        mLabelContainer->setSize(getSize());
 }
 
 void Button::getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>& quads, const IntRect& currentScissor)
 {
-    if (mLabelContainer->getSize() != getSize())
-        mLabelContainer->setSize(getSize());
-    
     if (mPressed)
         mImageRect = mPressedRect;
     else
         mImageRect = mInactiveRect;
     
     BorderImage::getBatches(batches, quads, currentScissor);
-    mHovering = false;
 }
 
 void Button::onHover(const IntVector2& position, const IntVector2& screenPosition, unsigned buttons)
@@ -125,19 +117,6 @@ void Button::setPressedRect(int left, int top, int right, int bottom)
     mPressedRect = IntRect(left, top, right, bottom);
 }
 
-void Button::setLabel(UIElement* label)
-{
-    mLabelContainer->removeChild(mLabel);
-    mLabel = label;
-    if (mLabel)
-    {
-        mLabelContainer->addChild(mLabel);
-        // Center the label element on the button forcibly
-        mLabel->setAlignment(HA_CENTER, VA_CENTER);
-        updateLabelOffset();
-    }
-}
-
 void Button::setLabelOffset(const IntVector2& offset)
 {
     mLabelOffset = offset;
@@ -150,14 +129,6 @@ void Button::setLabelOffset(int x, int y)
 
 void Button::setPressed(bool enable)
 {
-    if (enable != mPressed)
-    {
-        mPressed = enable;
-        updateLabelOffset();
-    }
-}
-
-void Button::updateLabelOffset()
-{
-    mLabelContainer->setPosition(mPressed ? mLabelOffset : IntVector2::sZero);
+    mPressed = enable;
+    setChildOffset(mPressed ? mLabelOffset : IntVector2::sZero);
 }

Engine/UI/Button.h

@@ -29,14 +29,16 @@
 //! An image that reacts to mouse presses
 class Button : public BorderImage
 {
+    DEFINE_TYPE(Button);
+    
 public:
     //! Construct with name
     Button(const std::string& name = std::string());
     //! Destruct
     virtual ~Button();
     
-    //! Load parameters from an XML file
-    virtual XMLElement loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache);
+    //! Set UI element style from XML data
+    virtual void setStyle(const XMLElement& element, ResourceCache* cache);
     //! Perform UI element update
     virtual void update(float timeStep);
     //! Return UI rendering batches
@@ -54,8 +56,6 @@ public:
     void setPressedRect(const IntRect& rect);
     //! Set pressed image rectangle
     void setPressedRect(int left, int top, int right, int bottom);
-    //! Set optional label UI element
-    void setLabel(UIElement* label);
     //! Set label offset on press
     void setLabelOffset(const IntVector2& offset);
     //! Set label offset on press
@@ -65,21 +65,13 @@ public:
     const IntRect& getInactiveRect() const { return mInactiveRect; }
     //! Return pressed image rectangle
     const IntRect& getPressedRect() const { return mPressedRect; }
-    //! Return label UI element
-    UIElement* getLabel() const { return mLabel; }
     //! Return label offset on press
     const IntVector2& getLabelOffset() const { return mLabelOffset; }
     
 protected:
     //! Set new pressed state
     void setPressed(bool enable);
-    //! Set offset of label depending on button press state
-    void updateLabelOffset();
     
-    //! Label UI element
-    SharedPtr<UIElement> mLabel;
-    //! Label container for offsetting
-    SharedPtr<UIElement> mLabelContainer;
     //! Inactive image rectangle
     IntRect mInactiveRect;
     //! Pressed image rectangle

Engine/UI/CheckBox.cpp

@@ -32,8 +32,8 @@
 
 CheckBox::CheckBox(const std::string& name) :
     BorderImage(name),
-    mUncheckedRect(0, 0, 0, 0),
-    mCheckedRect(0, 0, 0, 0),
+    mUncheckedRect(IntRect::sZero),
+    mCheckedRect(IntRect::sZero),
     mChecked(false)
 {
     mEnabled = true;
@@ -43,16 +43,17 @@ CheckBox::~CheckBox()
 {
 }
 
-XMLElement CheckBox::loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache)
+void CheckBox::setStyle(const XMLElement& element, ResourceCache* cache)
 {
-    XMLElement paramElem = BorderImage::loadParameters(file, elementName, cache);
+    if (!cache)
+        SAFE_EXCEPTION("Null resource cache for UI element");
     
-    if (paramElem.hasChildElement("uncheckedrect"))
-        setUncheckedRect(paramElem.getChildElement("uncheckedrect").getIntRect("value"));
-    if (paramElem.hasChildElement("checkedrect"))
-        setCheckedRect(paramElem.getChildElement("checkedrect").getIntRect("value"));
+    BorderImage::setStyle(element, cache);
     
-    return paramElem;
+    if (element.hasChildElement("uncheckedrect"))
+        setUncheckedRect(element.getChildElement("uncheckedrect").getIntRect("value"));
+    if (element.hasChildElement("checkedrect"))
+        setCheckedRect(element.getChildElement("checkedrect").getIntRect("value"));
 }
 
 void CheckBox::getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>& quads, const IntRect& currentScissor)
@@ -63,7 +64,6 @@ void CheckBox::getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>& qu
         mImageRect = mUncheckedRect;
     
     BorderImage::getBatches(batches, quads, currentScissor);
-    mHovering = false;
 }
 
 void CheckBox::onClick(const IntVector2& position, const IntVector2& screenPosition, unsigned buttons)

Engine/UI/CheckBox.h

@@ -28,14 +28,16 @@
 
 class CheckBox : public BorderImage
 {
+    DEFINE_TYPE(CheckBox);
+    
 public:
     //! Construct with name
     CheckBox(const std::string& name = std::string());
     //! Destruct
     virtual ~CheckBox();
     
-    //! Load parameters from an XML file
-    virtual XMLElement loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache);
+    //! Set UI element style from XML data
+    virtual void setStyle(const XMLElement& element, ResourceCache* cache);
     //! Return UI rendering batches
     virtual void getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>& quads, const IntRect& currentScissor);
     //! React to mouse click

Engine/UI/Cursor.cpp

@@ -40,14 +40,15 @@ Cursor::~Cursor()
 {
 }
 
-XMLElement Cursor::loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache)
+void Cursor::setStyle(const XMLElement& element, ResourceCache* cache)
 {
-    XMLElement paramElem = BorderImage::loadParameters(file, elementName, cache);
+    if (!cache)
+        SAFE_EXCEPTION("Null resource cache for UI element");
     
-    if (paramElem.hasChildElement("hotspot"))
-        setHotspot(paramElem.getChildElement("hotspot").getIntVector2("value"));
+    BorderImage::setStyle(element, cache);
     
-    return paramElem;
+    if (element.hasChildElement("hotspot"))
+        setHotspot(element.getChildElement("hotspot").getIntVector2("value"));
 }
 
 IntVector2 Cursor::getScreenPosition()

Engine/UI/Cursor.h

@@ -29,14 +29,16 @@
 //! An image with hotspot coordinates
 class Cursor : public BorderImage
 {
+    DEFINE_TYPE(Cursor);
+    
 public:
     //! Construct with name
     Cursor(const std::string& name = std::string());
     //! Destruct
     virtual ~Cursor();
     
-    //! Load parameters from an XML file
-    virtual XMLElement loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache);
+    //! Set UI element style from XML data
+    virtual void setStyle(const XMLElement& element, ResourceCache* cache);
     //! Return UI element screen position
     virtual IntVector2 getScreenPosition();
     

Engine/UI/Text.cpp

@@ -45,17 +45,34 @@ Text::~Text()
 {
 }
 
-XMLElement Text::loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache)
+void Text::setStyle(const XMLElement& element, ResourceCache* cache)
 {
-    XMLElement paramElem = UIElement::loadParameters(file, elementName, cache);
+    if (!cache)
+        SAFE_EXCEPTION("Null resource cache for UI element");
     
-    if (paramElem.hasChildElement("font"))
+    UIElement::setStyle(element, cache);
+    
+    if (element.hasChildElement("font"))
     {
-        XMLElement fontElem = paramElem.getChildElement("font");
+        XMLElement fontElem = element.getChildElement("font");
         setFont(cache->getResource<Font>(fontElem.getString("name")), fontElem.getInt("size"));
     }
-    
-    return paramElem;
+    if (element.hasChildElement("maxwidth"))
+        setMaxWidth(element.getChildElement("maxwidth").getInt("value"));
+    if (element.hasChildElement("text"))
+        setText(element.getChildElement("text").getString("value"));
+    if (element.hasChildElement("textspacing"))
+        setTextSpacing(element.getChildElement("textspacing").getFloat("value"));
+    if (element.hasChildElement("textalignment"))
+    {
+        std::string horiz = element.getChildElement("textalignment").getStringLower("value");
+        if (horiz == "left")
+            setTextAlignment(HA_LEFT);
+        if (horiz == "center")
+            setTextAlignment(HA_CENTER);
+        if (horiz == "right")
+            setTextAlignment(HA_RIGHT);
+    }
 }
 
 bool Text::setFont(Font* font, int size)
@@ -108,7 +125,11 @@ void Text::setTextSpacing(float spacing)
 void Text::getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>& quads, const IntRect& currentScissor)
 {
     if (!mFont)
+    {
+        mHovering = false;
         return;
+    }
+    
     const FontFace* face = mFont->getFace(mFontSize);
     
     UIBatch batch;
@@ -142,6 +163,9 @@ void Text::getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>& quads,
     }
     
     UIBatch::addOrMerge(batch, batches);
+    
+    // Reset hovering for next frame
+    mHovering = false;
 }
 
 int Text::getRowHeight() const

Engine/UI/Text.h

@@ -33,14 +33,16 @@ class Font;
 //! An UI element that displays text
 class Text : public UIElement
 {
+    DEFINE_TYPE(Text);
+    
 public:
     //! Construct with initial text and name
     Text(const std::string& text = std::string(), const std::string& name = std::string());
     //! Destruct
     virtual ~Text();
     
-    //! Load parameters from an XML file
-    virtual XMLElement loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache);
+    //! Set UI element style from XML data
+    virtual void setStyle(const XMLElement& element, ResourceCache* cache);
     //! Return UI rendering batches
     virtual void getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>& quads, const IntRect& currentScissor);
     

Engine/UI/UI.cpp

@@ -22,6 +22,7 @@
 //
 
 #include "Precompiled.h"
+#include "BaseUIElementFactory.h"
 #include "Cursor.h"
 #include "Font.h"
 #include "InputEvents.h"
@@ -33,6 +34,7 @@
 #include "RendererEvents.h"
 #include "RendererImpl.h"
 #include "ResourceCache.h"
+#include "StringUtils.h"
 #include "Texture2D.h"
 #include "UI.h"
 #include "VertexShader.h"
@@ -74,6 +76,9 @@ UI::UI(Renderer* renderer, ResourceCache* cache) :
     mNoTexturePS = mCache->getResource<PixelShader>("Shaders/SM2/Basic_VCol.ps2");
     mDiffTexturePS = mCache->getResource<PixelShader>("Shaders/SM2/Basic_DiffVCol.ps2");
     mAlphaTexturePS = mCache->getResource<PixelShader>("Shaders/SM2/Basic_AlphaVCol.ps2");
+    
+    // Add the base element factory
+    addElementFactory(new BaseUIElementFactory());
 }
 
 UI::~UI()
@@ -239,6 +244,66 @@ void UI::render()
     }
 }
 
+void UI::addElementFactory(UIElementFactory* factory)
+{
+    if (!factory)
+        return;
+    
+    mFactories.push_back(SharedPtr<UIElementFactory>(factory));
+}
+
+SharedPtr<UIElement> UI::createElement(ShortStringHash type, const std::string& name)
+{
+    SharedPtr<UIElement> element;
+    
+    for (unsigned i = 0; i < mFactories.size(); ++i)
+    {
+        element = mFactories[i]->createElement(type, name);
+        if (element)
+            return element;
+    }
+    
+    EXCEPTION("Could not create unknown UI element type " + toString(type));
+}
+
+SharedPtr<UIElement> UI::loadLayout(XMLFile* file, XMLFile* styleFile)
+{
+    PROFILE(UI_LoadLayout);
+    
+    SharedPtr<UIElement> root;
+    
+    if (!file)
+    {
+        LOGERROR("Null UI layout XML file");
+        return root;
+    }
+    
+    LOGDEBUG("Loading UI layout " + file->getName());
+    
+    XMLElement rootElem = file->getRootElement();
+    XMLElement childElem = rootElem.getChildElement("element", false);
+    if (!childElem)
+    {
+        LOGERROR("No root UI element in " + file->getName());
+        return root;
+    }
+    
+    root = createElement(ShortStringHash(childElem.getString("type")), childElem.getString("name", false));
+    
+    // First set the base style from the style file if exists, then apply UI layout overrides
+    if (styleFile)
+        root->setStyleAuto(styleFile, mCache);
+    root->setStyle(childElem, mCache);
+    
+    // Load rest of the elements recursively
+    loadLayout(root, childElem, styleFile);
+    
+    if (childElem.getNextElement("element"))
+        LOGWARNING("Ignored additional root UI elements in " + file->getName());
+    
+    return root;
+}
+
 UIElement* UI::getElementAt(const IntVector2& position, bool enabledOnly)
 {
     UIElement* result = 0;
@@ -441,3 +506,22 @@ void UI::handleChar(StringHash eventType, VariantMap& eventData)
     if (element)
         element->onChar(eventData[P_CHAR].getInt());
 }
+
+void UI::loadLayout(UIElement* current, const XMLElement& elem, XMLFile* styleFile)
+{
+    XMLElement childElem = elem.getChildElement("element", false);
+    while (childElem)
+    {
+        SharedPtr<UIElement> child = createElement(ShortStringHash(childElem.getString("type")), childElem.getString("name", false));
+        // First set the base style from the style file if exists, then apply UI layout overrides
+        if (styleFile)
+            child->setStyleAuto(styleFile, mCache);
+        child->setStyle(childElem, mCache);
+        
+        // Add to the hierarchy and recurse
+        current->addChild(child);
+        loadLayout(child, childElem, styleFile);
+        
+        childElem = childElem.getNextElement("element");
+    }
+}

Engine/UI/UI.h

@@ -31,8 +31,9 @@
 class Cursor;
 class Renderer;
 class ResourceCache;
-class UIElement;
 class UIBatch;
+class UIElement;
+class UIElementFactory;
 
 //! Manages the graphical user interface
 class UI : public RefCounted, public EventListener
@@ -53,6 +54,12 @@ public:
     void update(float timeStep);
     //! Render the UI
     void render();
+    //! Add a UI element factory
+    void addElementFactory(UIElementFactory* factory);
+    //! Create a UI element by type. Throw exception if can not create
+    SharedPtr<UIElement> createElement(ShortStringHash type, const std::string& name = std::string());
+    //! Load a UI layout from an XML file. Optionally specify another XML file for element style. Return the root element
+    SharedPtr<UIElement> loadLayout(XMLFile* file, XMLFile* styleFile = 0);
     
     //! Return root UI elemenet
     UIElement* getRootElement() const { return mRootElement; }
@@ -66,6 +73,8 @@ public:
     UIElement* getFocusElement();
     //! Return cursor position
     IntVector2 getCursorPosition();
+    //! Return UI element factories
+    const std::vector<SharedPtr<UIElementFactory> >& getElementFactories() const { return mFactories; }
     
 private:
     //! Update UI elements and generate batches for UI rendering
@@ -88,6 +97,8 @@ private:
     void handleMouseButtonUp(StringHash eventType, VariantMap& eventData);
     //! Handle character event
     void handleChar(StringHash eventType, VariantMap& eventData);
+    //! Load a UI layout from an XML file recursively
+    void loadLayout(UIElement* current, const XMLElement& elem, XMLFile* styleFile);
     
     //! Renderer
     SharedPtr<Renderer> mRenderer;
@@ -107,6 +118,8 @@ private:
     SharedPtr<UIElement> mRootElement;
     //! Cursor
     SharedPtr<Cursor> mCursor;
+    //! UI element factories
+    std::vector<SharedPtr<UIElementFactory> > mFactories;
     //! UI rendering batches
     std::vector<UIBatch> mBatches;
     //! UI rendering quads

Engine/UI/UIElement.cpp

@@ -37,6 +37,7 @@ UIElement::UIElement(const std::string& name) :
     mSize(IntVector2::sZero),
     mHorizontalAlignment(HA_LEFT),
     mVerticalAlignment(VA_TOP),
+    mChildOffset(IntVector2::sZero),
     mHoverColor(Color(0.0f, 0.0f, 0.0f)),
     mPriority(0),
     mOpacity(1.0f),
@@ -68,33 +69,18 @@ UIElement::~UIElement()
     }
 }
 
-XMLElement UIElement::loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache)
+void UIElement::setStyle(const XMLElement& element, ResourceCache* cache)
 {
-    if (!file)
-        SAFE_EXCEPTION_RET("Null UI definition file", XMLElement());
     if (!cache)
-        SAFE_EXCEPTION_RET("Null resource cache", XMLElement());
+        SAFE_EXCEPTION("Null resource cache for UI element");
     
-    XMLElement rootElem = file->getRootElement();
-    XMLElement paramElem = rootElem.getChildElement("element", false);
-    
-    while (paramElem.notNull())
-    {
-        if (paramElem.getString("name") == elementName)
-            break;
-        paramElem = paramElem.getNextElement("element");
-    }
-    
-    if (paramElem.isNull())
-        SAFE_EXCEPTION_RET("No UI element definition " + elementName + " in " + file->getName(), XMLElement());
-    
-    if (paramElem.hasChildElement("position"))
-        setPosition(paramElem.getChildElement("position").getIntVector2("value"));
-    if (paramElem.hasChildElement("size"))
-        setSize(paramElem.getChildElement("size").getIntVector2("value"));
-    if (paramElem.hasChildElement("alignment"))
+    if (element.hasChildElement("position"))
+        setPosition(element.getChildElement("position").getIntVector2("value"));
+    if (element.hasChildElement("size"))
+        setSize(element.getChildElement("size").getIntVector2("value"));
+    if (element.hasChildElement("alignment"))
     {
-        XMLElement alignElem = paramElem.getChildElement("alignment");
+        XMLElement alignElem = element.getChildElement("alignment");
         
         std::string horiz;
         std::string vert;
@@ -119,13 +105,13 @@ XMLElement UIElement::loadParameters(XMLFile* file, const std::string& elementNa
         if (vert == "bottom")
             setVerticalAlignment(VA_BOTTOM);
     }
-    if (paramElem.hasChildElement("priority"))
-        setPriority(paramElem.getChildElement("priority").getInt("value"));
-    if (paramElem.hasChildElement("opacity"))
-        setOpacity(paramElem.getChildElement("opacity").getFloat("value"));
-    if (paramElem.hasChildElement("color"))
+    if (element.hasChildElement("priority"))
+        setPriority(element.getChildElement("priority").getInt("value"));
+    if (element.hasChildElement("opacity"))
+        setOpacity(element.getChildElement("opacity").getFloat("value"));
+    if (element.hasChildElement("color"))
     {
-        XMLElement colorElem = paramElem.getChildElement("color");
+        XMLElement colorElem = element.getChildElement("color");
         if (colorElem.hasAttribute("value"))
             setColor(colorElem.getColor("value"));
         if (colorElem.hasAttribute("topleft"))
@@ -137,20 +123,18 @@ XMLElement UIElement::loadParameters(XMLFile* file, const std::string& elementNa
         if (colorElem.hasAttribute("bottomright"))
             setColor(C_BOTTOMRIGHT, colorElem.getColor("bottomright"));
     }
-    if (paramElem.hasChildElement("hovercolor"))
-        setHoverColor(paramElem.getChildElement("hovercolor").getColor("value"));
-    if (paramElem.hasChildElement("bringtofront"))
-        setBringToFront(paramElem.getChildElement("bringtofront").getBool("enable"));
-    if (paramElem.hasChildElement("clipchildren"))
-        setClipChildren(paramElem.getChildElement("clipchildren").getBool("enable"));
-    if (paramElem.hasChildElement("enabled"))
-        setEnabled(paramElem.getChildElement("enabled").getBool("enable"));
-    if (paramElem.hasChildElement("focusable"))
-        setFocusable(paramElem.getChildElement("focusable").getBool("enable"));
-    if (paramElem.hasChildElement("visible"))
-        setVisible(paramElem.getChildElement("visible").getBool("enable"));
-    
-    return paramElem;
+    if (element.hasChildElement("hovercolor"))
+        setHoverColor(element.getChildElement("hovercolor").getColor("value"));
+    if (element.hasChildElement("bringtofront"))
+        setBringToFront(element.getChildElement("bringtofront").getBool("enable"));
+    if (element.hasChildElement("clipchildren"))
+        setClipChildren(element.getChildElement("clipchildren").getBool("enable"));
+    if (element.hasChildElement("enabled"))
+        setEnabled(element.getChildElement("enabled").getBool("enable"));
+    if (element.hasChildElement("focusable"))
+        setFocusable(element.getChildElement("focusable").getBool("enable"));
+    if (element.hasChildElement("visible"))
+        setVisible(element.getChildElement("visible").getBool("enable"));
 }
 
 void UIElement::update(float timeStep)
@@ -159,6 +143,7 @@ void UIElement::update(float timeStep)
 
 void UIElement::getBatches(std::vector<UIBatch>& batches, std::vector<UIQuad>& quads, const IntRect& currentScissor)
 {
+    // Reset hovering for next frame
     mHovering = false;
 }
 
@@ -201,6 +186,8 @@ IntVector2 UIElement::getScreenPosition()
                 break;
             }
             
+            pos += parent->mChildOffset;
+            
             current = parent;
             parent = parent->mParent;
         }
@@ -397,6 +384,12 @@ void UIElement::setVisible(bool enable)
     mVisible = enable;
 }
 
+void UIElement::setStyleAuto(XMLFile* file, ResourceCache* cache)
+{
+    XMLElement element = getStyleElement(file);
+    setStyle(element, cache);
+}
+
 void UIElement::addChild(UIElement* element)
 {
     if ((!element) || (element->mParent == this) || (mParent == element))
@@ -495,6 +488,23 @@ UIElement* UIElement::getChild(const std::string& name, bool recursive) const
     return 0;
 }
 
+XMLElement UIElement::getStyleElement(XMLFile* file) const
+{
+    if (file)
+    {
+        XMLElement rootElem = file->getRootElement();
+        XMLElement childElem = rootElem.getChildElement("element", false);
+        while (childElem)
+        {
+            if (childElem.getString("type", false) == getTypeName())
+                return childElem;
+            childElem = childElem.getNextElement("element");
+        }
+    }
+    
+    return XMLElement();
+}
+
 IntVector2 UIElement::screenToElement(const IntVector2& screenPosition)
 {
     return screenPosition - getScreenPosition();
@@ -517,6 +527,23 @@ void UIElement::adjustScissor(IntRect& currentScissor)
     }
 }
 
+XMLElement UIElement::getStyleElement(XMLFile* file, const std::string& typeName)
+{
+    if (file)
+    {
+        XMLElement rootElem = file->getRootElement();
+        XMLElement childElem = rootElem.getChildElement("element", false);
+        while (childElem)
+        {
+            if (childElem.getString("type", false) == typeName)
+                return childElem;
+            childElem = childElem.getNextElement("element");
+        }
+    }
+    
+    return XMLElement();
+}
+
 void UIElement::markDirty()
 {
     if ((mScreenPositionDirty) && (mDerivedOpacityDirty))
@@ -529,6 +556,16 @@ void UIElement::markDirty()
         (*i)->markDirty();
 }
 
+void UIElement::setChildOffset(const IntVector2& offset)
+{
+    if (offset != mChildOffset)
+    {
+        mChildOffset = offset;
+        for (std::vector<SharedPtr<UIElement> >::const_iterator i = mChildren.begin(); i != mChildren.end(); ++i)
+            (*i)->markDirty();
+    }
+}
+
 void UIElement::getChildrenRecursive(std::vector<UIElement*>& dest) const
 {
     for (std::vector<SharedPtr<UIElement> >::const_iterator i = mChildren.begin(); i != mChildren.end(); ++i)

Engine/UI/UIElement.h

@@ -25,6 +25,7 @@
 #define UI_UIELEMENT_H
 
 #include "EventListener.h"
+#include "HashedType.h"
 #include "SharedPtr.h"
 #include "UIBatch.h"
 #include "Vector2.h"
@@ -60,16 +61,18 @@ static const unsigned NUM_UIELEMENT_CORNERS = 4;
 class ResourceCache;
 
 //! Base class for UI elements
-class UIElement : public RefCounted, public EventListener
+class UIElement : public HashedType, public EventListener
 {
+    DEFINE_TYPE(UIElement);
+    
 public:
     //! Construct with name
     UIElement(const std::string& name = std::string());
     //! Destruct with name
     virtual ~UIElement();
     
-    //! Load parameters from an XML file
-    virtual XMLElement loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache);
+    //! Set UI element style from XML data
+    virtual void setStyle(const XMLElement& element, ResourceCache* cache);
     //! Perform UI element update
     virtual void update(float timeStep);
     //! Return UI rendering batches
@@ -116,7 +119,7 @@ public:
     void setColor(const Color& color);
     //! Set color on one corner
     void setColor(UIElementCorner corner, const Color& color);
-    //! Set hover color modification
+    //! Set color modification used on hover
     void setHoverColor(const Color& color);
     //! Set priority
     void setPriority(int priority);
@@ -134,6 +137,8 @@ public:
     void setFocus(bool enable);
     //! Set whether is visible
     void setVisible(bool enable);
+    //! Set style from an XML file. Find the style element automatically
+    void setStyleAuto(XMLFile* file, ResourceCache* cache);
     //! Add a child element
     void addChild(UIElement* element);
     //! Remove a child element
@@ -151,13 +156,15 @@ public:
     int getWidth() const { return mSize.mX; }
     //! Return height
     int getHeight() const { return mSize.mY; }
+    //! Return child element offset
+    const IntVector2& getChildOffset() const { return mChildOffset; }
     //! Return horizontal alignment
     HorizontalAlignment getHorizontalAlignment() const { return mHorizontalAlignment; }
     //! Return vertical alignment
     VerticalAlignment getVerticalAlignment() const { return mVerticalAlignment; }
     //! Return corner color
     const Color& getColor(UIElementCorner corner) const { return mColor[corner]; }
-    //! Return hover color modification
+    //! Return color modification used on hover
     const Color& getHoverColor() { return mHoverColor; }
     //! Return priority
     int getPriority() const { return mPriority; }
@@ -189,6 +196,8 @@ public:
     std::vector<UIElement*> getChildren(bool recursive = false) const;
     //! Return parent element
     UIElement* getParent() const { return mParent; }
+    //! Return first matching UI style element from an XML file. If not found, return empty
+    XMLElement getStyleElement(XMLFile* file) const;
     
     //! Convert screen coordinates to element coordinates
     IntVector2 screenToElement(const IntVector2& screenPosition);
@@ -198,9 +207,14 @@ public:
     //! Adjust scissor for rendering
     void adjustScissor(IntRect& currentScissor);
     
+    //! Return first matching UI style element from an XML file, with freely specified type. If not found, return empty
+    static XMLElement getStyleElement(XMLFile* file, const std::string& typeName);
+    
 protected:
     //! Mark screen position as needing an update
     void markDirty();
+    //! Set child offset
+    void setChildOffset(const IntVector2& offset);
     
     //! Name
     std::string mName;
@@ -210,7 +224,7 @@ protected:
     UIElement* mParent;
     //! Colors
     Color mColor[NUM_UIELEMENT_CORNERS];
-    //! Hover color modification
+    //! Color modification on hover
     Color mHoverColor;
     //! Priority
     int mPriority;
@@ -239,6 +253,8 @@ private:
     IntVector2 mScreenPosition;
     //! Size
     IntVector2 mSize;
+    //! Child elements' offset. Used internally
+    IntVector2 mChildOffset;
     //! Horizontal alignment
     HorizontalAlignment mHorizontalAlignment;
     //! Vertical alignment

Engine/UI/UIElementFactory.h

@@ -0,0 +1,40 @@
+//
+// Urho3D Engine
+// Copyright (c) 2008-2011 Lasse Öörni
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+
+#ifndef UI_UIELEMENTFACTORY_H
+#define UI_UIELEMENTFACTORY_H
+
+#include "RefCount.h"
+#include "StringHash.h"
+
+class UIElement;
+
+//! Base class for UI element factories
+class UIElementFactory : public RefCounted
+{
+public:
+    //! Create a UI element of the specified type. Return null if can not create
+    virtual UIElement* createElement(ShortStringHash type, const std::string& name = std::string()) = 0;
+};
+
+#endif // UI_UIELEMENTFACTORY

Engine/UI/Window.cpp

@@ -49,22 +49,23 @@ Window::~Window()
 {
 }
 
-XMLElement Window::loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache)
+void Window::setStyle(const XMLElement& element, ResourceCache* cache)
 {
-    XMLElement paramElem = BorderImage::loadParameters(file, elementName, cache);
+    if (!cache)
+        SAFE_EXCEPTION("Null resource cache for UI element");
     
-    if (paramElem.hasChildElement("minsize"))
-        setMinSize(paramElem.getChildElement("minsize").getIntVector2("value"));
-    if (paramElem.hasChildElement("maxsize"))
-        setMaxSize(paramElem.getChildElement("maxsize").getIntVector2("value"));
-    if (paramElem.hasChildElement("resizeborder"))
-        setResizeBorder(paramElem.getChildElement("resizeborder").getIntRect("value"));
-    if (paramElem.hasChildElement("movable"))
-        setMovable(paramElem.getChildElement("movable").getBool("enable"));
-    if (paramElem.hasChildElement("resizable"))
-        setResizable(paramElem.getChildElement("resizable").getBool("enable"));
+    BorderImage::setStyle(element, cache);
     
-    return paramElem;
+    if (element.hasChildElement("minsize"))
+        setMinSize(element.getChildElement("minsize").getIntVector2("value"));
+    if (element.hasChildElement("maxsize"))
+        setMaxSize(element.getChildElement("maxsize").getIntVector2("value"));
+    if (element.hasChildElement("resizeborder"))
+        setResizeBorder(element.getChildElement("resizeborder").getIntRect("value"));
+    if (element.hasChildElement("movable"))
+        setMovable(element.getChildElement("movable").getBool("enable"));
+    if (element.hasChildElement("resizable"))
+        setResizable(element.getChildElement("resizable").getBool("enable"));
 }
 
 void Window::onDragStart(const IntVector2& position, const IntVector2& screenPosition, unsigned buttons)

Engine/UI/Window.h

@@ -46,14 +46,16 @@ enum WindowDragMode
 //! Window that can optionally by moved or resized
 class Window : public BorderImage
 {
+    DEFINE_TYPE(Window);
+    
 public:
     //! Construct with name
     Window(const std::string& name = std::string());
     //! Destruct
     virtual ~Window();
     
-    //! Load parameters from an XML file
-    virtual XMLElement loadParameters(XMLFile* file, const std::string& elementName, ResourceCache* cache);
+    //! Set UI element style from XML data
+    virtual void setStyle(const XMLElement& element, ResourceCache* cache);
     //! React to mouse drag start
     virtual void onDragStart(const IntVector2& position, const IntVector2& screenPosition, unsigned buttons);
     //! React to mouse drag motion

Examples/Test/Application.cpp

@@ -28,8 +28,6 @@
 #include "Audio.h"
 #include "Application.h"
 #include "BillboardSet.h"
-#include "Button.h"
-#include "CheckBox.h"
 #include "CollisionShape.h"
 #include "Cursor.h"
 #include "CustomObject.h"
@@ -199,29 +197,15 @@ void Application::init()
     UI* ui = mEngine->getUI();
     UIElement* uiRoot = ui->getRootElement();
     
-    XMLFile* uiSetup = mCache->getResource<XMLFile>("UI/UI.xml");
+    XMLFile* uiStyle = mCache->getResource<XMLFile>("UI/DefaultStyle.xml");
     
     Cursor* cursor = new Cursor("Cursor");
-    cursor->loadParameters(uiSetup, "Cursor", mCache);
+    cursor->setStyleAuto(uiStyle, mCache);
     cursor->setPosition(renderer->getWidth() / 2, renderer->getHeight() / 2);
     ui->setCursor(cursor);
     
-    //Button* button = new Button("TestButton");
-    //button->loadParameters(uiSetup, "Button", mCache);
-    //Text* text = new Text("TEST");
-    //text->setFont(mCache->getResource<Font>("cour.ttf"), 12);
-    //button->setLabel(text);
-    //button->setAlignment(HA_CENTER, VA_CENTER);
-    //button->setSize(100, 40);
-    //uiRoot->addChild(button);
-    //
-    //for (unsigned i = 0; i < 4; ++i)
-    //{
-    //    CheckBox* checkBox = new CheckBox("TestCheckBox" + toString(i));
-    //    checkBox->loadParameters(uiSetup, "CheckBox", mCache);
-    //    checkBox->setPosition(renderer->getWidth() / 3, renderer->getHeight() / 3 + 32 * i);
-    //    uiRoot->addChild(checkBox);
-    //}
+    //XMLFile* uiLayout = mCache->getResource<XMLFile>("UI/TestLayout.xml");
+    //uiRoot->addChild(ui->loadLayout(uiLayout, uiStyle));
     
     mScene = mEngine->createScene();
     PhysicsWorld* world = mScene->getExtension<PhysicsWorld>();