diff --git a/src/viewport_sprite_sorter.h b/src/viewport_sprite_sorter.h
new file mode 100644
--- /dev/null
+++ b/src/viewport_sprite_sorter.h
@@ -0,0 +1,58 @@
+/* $Id$ */
+
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD 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, version 2.
+ * OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file viewport_sprite_sorter.h Types related to sprite sorting. */
+
+#include "stdafx.h"
+#include "core/smallvec_type.hpp"
+#include "gfx_type.h"
+
+#ifndef VIEWPORT_SPRITE_SORTER_H
+#define VIEWPORT_SPRITE_SORTER_H
+
+/** Parent sprite that should be drawn */
+struct ParentSpriteToDraw {
+	/* Block of 16B loadable in xmm register */
+	int32 xmin;                     ///< minimal world X coordinate of bounding box
+	int32 ymin;                     ///< minimal world Y coordinate of bounding box
+	int32 zmin;                     ///< minimal world Z coordinate of bounding box
+	int32 x;                        ///< screen X coordinate of sprite
+
+	/* Second block of 16B loadable in xmm register */
+	int32 xmax;                     ///< maximal world X coordinate of bounding box
+	int32 ymax;                     ///< maximal world Y coordinate of bounding box
+	int32 zmax;                     ///< maximal world Z coordinate of bounding box
+	int32 y;                        ///< screen Y coordinate of sprite
+
+	SpriteID image;                 ///< sprite to draw
+	PaletteID pal;                  ///< palette to use
+	const SubSprite *sub;           ///< only draw a rectangular part of the sprite
+
+	int32 left;                     ///< minimal screen X coordinate of sprite (= x + sprite->x_offs), reference point for child sprites
+	int32 top;                      ///< minimal screen Y coordinate of sprite (= y + sprite->y_offs), reference point for child sprites
+
+	int first_child;                ///< the first child to draw.
+	bool comparison_done;           ///< Used during sprite sorting: true if sprite has been compared with all other sprites
+};
+
+typedef SmallVector<ParentSpriteToDraw*, 64> ParentSpriteToSortVector;
+
+/** Type for method for checking whether a viewport sprite sorter exists. */
+typedef bool (*VpSorterChecker)();
+/** Type for the actual viewport sprite sorter. */
+typedef void (*VpSpriteSorter)(ParentSpriteToSortVector *psd);
+
+#ifdef WITH_SSE
+bool ViewportSortParentSpritesSSE41Checker();
+void ViewportSortParentSpritesSSE41(ParentSpriteToSortVector *psdv);
+#endif
+
+void InitializeSpriteSorter();
+
+#endif /* VIEWPORT_SPRITE_SORTER_H */