Graphics: Add origin to all sprite-based renderables (and made it a factor)

include/Nazara/Graphics/SlicedSprite.inl

@@ -23,6 +23,16 @@ namespace Nz
 		return m_textureCoords;
 	}
 
+	inline const Vector2f& SlicedSprite::GetOrigin() const
+	{
+		return m_origin;
+	}
+
+	inline const Vector2f& SlicedSprite::GetSize() const
+	{
+		return m_size;
+	}
+
 	inline auto SlicedSprite::GetTopLeftCorner() const -> const Corner&
 	{
 		return m_topLeftCorner;
@@ -72,6 +82,13 @@ namespace Nz
 		}
 	}
 
+	inline void SlicedSprite::SetOrigin(const Vector2f& origin)
+	{
+		m_origin = origin;
+
+		UpdateVertices();
+	}
+
 	inline void SlicedSprite::SetSize(const Vector2f& size)
 	{
 		m_size = size;