add window functions and title screen windows

src/widget.h

@@ -0,0 +1,45 @@
+/*****************************************************************************
+ * Copyright (c) 2014 Ted John
+ * OpenRCT2, an open source clone of Roller Coaster Tycoon 2.
+ *
+ * This file is part of OpenRCT2.
+ *
+ * OpenRCT2 is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ 
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *****************************************************************************/
+
+#ifndef _WIDGET_H_
+#define _WIDGET_H_
+
+typedef enum {
+	WWT_EMPTY = 0,
+	WWT_FRAME = 1,
+	WWT_RESIZE = 2,
+	WWT_IMGBTN = 3,
+	WWT_4 = 4,
+	WWT_TRNBTN = 7,
+	WWT_TAB = 8,
+	WWT_FLATBTN = 9,
+	WWT_DROPDOWN_BUTTON = 10,
+	WWT_12 = 12,
+	WWT_DROPDOWN = 16,
+	WWT_VIEWPORT = 17,
+	WWT_CAPTION = 20,
+	WWT_CLOSEBOX = 21,
+	WWT_SCROLL = 22,
+	WWT_25 = 25,
+	WWT_LAST = 26,
+} WINDOW_WIDGET_TYPES;
+#define WIDGETS_END		WWT_LAST, 0, 0, 0, 0, 0, 0, 0
+
+#endif