+++ /dev/null
-/***************************************************************************
-* Copyright (C) 2016 PCSX4ALL Team *
-* *
-* 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 02111-1307 USA. *
-***************************************************************************/
-
-#ifndef _OP_DITHER_H_
-#define _OP_DITHER_H_
-
-static void SetupDitheringConstants()
-{
- // Initialize Dithering Constants
- // The screen is divided into 8x8 chunks and sub-unitary noise is applied
- // using the following matrix. This ensures that data lost in color
- // quantization will be added back to the image 'by chance' in predictable
- // patterns that are naturally 'smoothed' by your sight when viewed from a
- // certain distance.
- //
- // http://caca.zoy.org/study/index.html
- //
- // Shading colors are encoded in 4.5, and then are quantitized to 5.0,
- // DitherMatrix constants reflect that.
-
- static const u8 DitherMatrix[] = {
- 0, 32, 8, 40, 2, 34, 10, 42,
- 48, 16, 56, 24, 50, 18, 58, 26,
- 12, 44, 4, 36, 14, 46, 6, 38,
- 60, 28, 52, 20, 62, 30, 54, 22,
- 3, 35, 11, 43, 1, 33, 9, 41,
- 51, 19, 59, 27, 49, 17, 57, 25,
- 15, 47, 7, 39, 13, 45, 5, 37,
- 63, 31, 55, 23, 61, 29, 53, 21
- };
-
- int i, j;
- for (i = 0; i < 8; i++)
- {
- for (j = 0; j < 8; j++)
- {
- u16 offset = (i << 3) | j;
-
- u32 component = ((DitherMatrix[offset] + 1) << 4) / 65; //[5.5] -> [5]
-
- // XXX - senquack - hack Dec 2016
- // Until JohnnyF gets the time to work further on dithering,
- // force lower bit of component to 0. This fixes grid pattern
- // affecting quality of dithered image, as well as loss of
- // detail in dark areas. With lower bit unset like this, existing
- // 27-bit accuracy of dithering math is unneeded, could be 24-bit.
- // Is 8x8 matrix overkill as a result, can we use 4x4?
- component &= ~1;
-
- gpu_senquack.DitherMatrix[offset] = (component)
- | (component << 10)
- | (component << 20);
- }
- }
-}
-
-////////////////////////////////////////////////////////////////////////////////
-// Convert padded u32 5.4:5.4:5.4 bgr fixed-pt triplet to final bgr555 color,
-// applying dithering if specified by template parameter.
-//
-// INPUT:
-// 'uSrc24' input: 000bbbbbXXXX0gggggXXXX0rrrrrXXXX
-// ^ bit 31
-// 'pDst' is a pointer to destination framebuffer pixel, used
-// to determine which DitherMatrix[] entry to apply.
-// RETURNS:
-// u16 output: 0bbbbbgggggrrrrr
-// ^ bit 16
-// Where 'X' are fixed-pt bits, '0' is zero-padding, and '-' is don't care
-////////////////////////////////////////////////////////////////////////////////
-template <int DITHER>
-GPU_INLINE u16 gpuColorQuantization24(u32 uSrc24, const u16 *pDst)
-{
- if (DITHER)
- {
- u16 fbpos = (u32)(pDst - gpu_senquack.vram);
- u16 offset = ((fbpos & (0x7 << 10)) >> 7) | (fbpos & 0x7);
-
- //clean overflow flags and add
- uSrc24 = (uSrc24 & 0x1FF7FDFF) + gpu_senquack.DitherMatrix[offset];
-
- if (uSrc24 & (1<< 9)) uSrc24 |= (0x1FF );
- if (uSrc24 & (1<<19)) uSrc24 |= (0x1FF<<10);
- if (uSrc24 & (1<<29)) uSrc24 |= (0x1FF<<20);
- }
-
- return ((uSrc24>> 4) & (0x1F ))
- | ((uSrc24>> 9) & (0x1F<<5 ))
- | ((uSrc24>>14) & (0x1F<<10));
-}
-
-#endif //_OP_DITHER_H_
notaz.gp2x.de / pcsx_rearmed.git / blobdiff