smsplus-gx/source/scale2x/scale2x.c
gameblabla 7b307cce26
Change the Scale2 code a bit as to make use of 16-bits pointers
instead of 8-bits pointers. This should greatly improve the speed
on devices like the RS-97 and GCW0.
2019-03-22 08:38:02 +01:00

65 lines
2.3 KiB
C

/* scaler.c: code for selecting (etc) scalers
* Copyright (C) 2003 Fredrick Meunier, Philip Kendall
* Copyright (c) 2015 Sergio Baldoví
*
* $Id: scaler.c 5432 2016-05-01 04:16:09Z fredm $
*
* Originally taken from ScummVM - Scumm Interpreter
* Copyright (C) 2001 Ludvig Strigeus
* Copyright (C) 2001/2002 The ScummVM project
*
* HQ2x and HQ3x scalers taken from HiEnd3D Demos (http://www.hiend3d.com)
* Copyright (C) 2003 MaxSt ( maxst@hiend3d.com )
*
* 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.
*
*/
#include "scale2x.h"
/* No license ? Scale2x was licensed under the GPLv2 and this code was found among in GPLv2 licensed code.
* I had to make some minor modifications to it and the code is fairly small but i think we should be good. */
void scale2x(uint16_t* restrict srcpixels, uint16_t* restrict dstpixels, const uint32_t srcpitch, const uint32_t dstpitch, const uint32_t width, uint32_t height)
{
uint32_t nextlineSrc = srcpitch / sizeof(uint16_t);
uint16_t* restrict p = (uint16_t* restrict)srcpixels;
uint32_t nextlineDst = dstpitch / sizeof(uint16_t);
uint16_t* restrict q = (uint16_t* restrict)dstpixels;
uint32_t i, j;
uint16_t B, D, E, F, H;
while(height--)
{
j = 0;
for(i = 0; i < width; ++i, j += 2) {
B = *(p + i - nextlineSrc);
D = *(p + i - 1);
E = *(p + i);
F = *(p + i + 1);
H = *(p + i + nextlineSrc);
*(q + j) = (uint16_t)(D == B && B != F && D != H ? D : E);
*(q + j + 1) = (uint16_t)(B == F && B != D && F != H ? F : E);
*(q + j + nextlineDst) = (uint16_t)(D == H && D != B && H != F ? D : E);
*(q + j + nextlineDst + 1) = (uint16_t)(H == F && D != H && B != F ? F : E);
}
p += nextlineSrc;
q += nextlineDst << 1;
}
}