Preserve current legacy presentation and options improvements

raptor/src/i_upscale.h

@@ -0,0 +1,28 @@
+//
+// Copyright(C) 1993-1996 Id Software, Inc.
+// Copyright(C) 2005-2014 Simon Howard
+//
+// This program 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 2
+// 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.
+//
+// DESCRIPTION:
+//	Presentation-level pixel-art upscaler (AdvMAME scale2x/scale3x).
+//
+
+#pragma once
+
+#include <stdint.h>
+
+// Upscale a w x h 32-bit RGBA frame by factor (2, 3 or 4) into dst, which
+// must be w*factor x h*factor pixels. Pitches are in pixels, not bytes;
+// the caller converts surface pitches. No SDL dependency, no global state.
+
+void I_UpscaleFrame(const uint32_t *src, int srcpitch_px, int w, int h,
+                    uint32_t *dst, int dstpitch_px, int factor);