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/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * 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.

 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * $URL$
 * $Id$
 *
 */

/* This file isn't used directly; rather, it's included by a different file. */
/* Note that memcpy() is assumed to be an inlineable built-in. If it isn't,
** performance will suck... badly.
*/
/* Config parameters:
** FUNCTION_NAME: Name of the blitter function
** USE_PRIORITY: Whether to care about the priority buffer
** BYTESPP: Bytes per pixel
*/

#include "common/scummsys.h"

/* set optimisations for Win32: */
/* g on: enable global optimizations */
/* t on: use fast code */
/* y on: suppress creation of frame pointers on stack */
/* s off: disable minimize size code */
#ifdef WIN32
#	include <memory.h>
#	ifndef SATISFY_PURIFY
#		pragma optimize( "s", off )
#		pragma optimize( "gty", on )
#		pragma intrinsic( memcpy, memset )
#	endif
#endif

namespace Sci {

static void FUNCTION_NAME(byte *dest, byte *src, int bytes_per_dest_line, int bytes_per_src_line,
                          int xl, int yl, byte *alpha, int bytes_per_alpha_line, int bytes_per_alpha_pixel,
                          unsigned int alpha_test_mask, unsigned int alpha_min
#ifdef USE_PRIORITY
                          , byte *priority_buffer, int bytes_per_priority_line, int bytes_per_priority_pixel, int priority
#endif /* USE_PRIORITY */
                         ) {
	int x, y;
	int alpha_end = xl * bytes_per_alpha_pixel;

	for (y = 0; y < yl; y++) {
		int pixel_offset = 0;
		int alpha_offset = 0;
#ifdef USE_PRIORITY
		int priority_offset = 0;
#endif /* USE_PRIORITY */

		for (x = 0; x < alpha_end; x += bytes_per_alpha_pixel) {
			if ((alpha_test_mask & alpha[x])
#ifdef REVERSE_ALPHA
			        >=
#else
			        <
#endif
			        alpha_min)
#ifdef USE_PRIORITY
				if (priority_buffer[priority_offset] <= priority) {
					priority_buffer[priority_offset] = priority;
#endif /* USE_PRIORITY */
					memcpy(dest + pixel_offset, src + pixel_offset, BYTESPP);
#ifdef USE_PRIORITY
				}
#endif /* USE_PRIORITY */

			pixel_offset += BYTESPP;
			alpha_offset += bytes_per_alpha_pixel;
#ifdef USE_PRIORITY
			priority_offset += bytes_per_priority_pixel;
#endif /* USE_PRIORITY */
		}

		dest += bytes_per_dest_line;
		src += bytes_per_src_line;
		alpha += bytes_per_alpha_line;
#ifdef USE_PRIORITY
		priority_buffer += bytes_per_priority_line;
#endif /* USE_PRIORITY */
	}
}

} // End of namespace Sci

/* reset to original optimisations for Win32: */
/* (does not reset intrinsics) */
#ifdef WIN32
#  pragma optimize( "", on )
#endif