Implement per-client randomized menus with MenuShufflePerClient native.

Add MenuSetClientMapping native.

core/MenuStyle_Base.cpp

@@ -754,6 +754,62 @@ unsigned int CBaseMenu::GetRealItemIndex(int client, unsigned int position)
 	return position;
 }
 
+void CBaseMenu::ShufflePerClient(int start, int stop)
+{
+	// limit map len to 255 items since it's using uint8
+	int length = MIN(GetItemCount(), 255);
+	if (stop >= 0)
+		length = MIN(length, stop);
+
+	for (int i = 1; i < SM_MAXPLAYERS + 1; i++)
+	{
+		// populate per-client map ...
+		m_RandomMaps[i].resize(length);
+		for (int j = 0; j < length; j++)
+			m_RandomMaps[i][j] = j;
+
+		// ... and random shuffle it
+		for (int j = length - 1; j > start; j--)
+		{
+			int x = rand() % (j - start + 1) + start;
+			uint8_t tmp = m_RandomMaps[i][x];
+			m_RandomMaps[i][x] = m_RandomMaps[i][j];
+			m_RandomMaps[i][j] = tmp;
+		}
+	}
+}
+
+void CBaseMenu::SetClientMapping(int client, int *array, int length)
+{
+	length = MIN(length, 255);
+	m_RandomMaps[client].resize(length);
+	for (int i = 0; i < length; i++)
+	{
+		m_RandomMaps[client][i] = array[i];
+	}
+}
+
+bool CBaseMenu::IsPerClientShuffled()
+{
+	for (int i = 1; i < SM_MAXPLAYERS + 1; i++)
+	{
+		if(m_RandomMaps[i].length() > 0)
+			return true;
+	}
+	return false;
+}
+
+unsigned int CBaseMenu::GetRealItemIndex(int client, unsigned int position)
+{
+	if (client > 0 && position < m_RandomMaps[client].length())
+	{
+		position = m_RandomMaps[client][position];
+		return m_items[position].index;
+	}
+
+	return position;
+}
+
 unsigned int CBaseMenu::GetItemCount()
 {
 	return m_items.size();