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-rw-r--r--source/dsp2emu.c160
1 files changed, 9 insertions, 151 deletions
diff --git a/source/dsp2emu.c b/source/dsp2emu.c
index 43bfb45..1ec79bc 100644
--- a/source/dsp2emu.c
+++ b/source/dsp2emu.c
@@ -1,94 +1,4 @@
-/*******************************************************************************
- Snes9x - Portable Super Nintendo Entertainment System (TM) emulator.
-
- (c) Copyright 1996 - 2002 Gary Henderson (gary.henderson@ntlworld.com) and
- Jerremy Koot (jkoot@snes9x.com)
-
- (c) Copyright 2001 - 2004 John Weidman (jweidman@slip.net)
-
- (c) Copyright 2002 - 2004 Brad Jorsch (anomie@users.sourceforge.net),
- funkyass (funkyass@spam.shaw.ca),
- Joel Yliluoma (http://iki.fi/bisqwit/)
- Kris Bleakley (codeviolation@hotmail.com),
- Matthew Kendora,
- Nach (n-a-c-h@users.sourceforge.net),
- Peter Bortas (peter@bortas.org) and
- zones (kasumitokoduck@yahoo.com)
-
- C4 x86 assembler and some C emulation code
- (c) Copyright 2000 - 2003 zsKnight (zsknight@zsnes.com),
- _Demo_ (_demo_@zsnes.com), and Nach
-
- C4 C++ code
- (c) Copyright 2003 Brad Jorsch
-
- DSP-1 emulator code
- (c) Copyright 1998 - 2004 Ivar (ivar@snes9x.com), _Demo_, Gary Henderson,
- John Weidman, neviksti (neviksti@hotmail.com),
- Kris Bleakley, Andreas Naive
-
- DSP-2 emulator code
- (c) Copyright 2003 Kris Bleakley, John Weidman, neviksti, Matthew Kendora, and
- Lord Nightmare (lord_nightmare@users.sourceforge.net
-
- OBC1 emulator code
- (c) Copyright 2001 - 2004 zsKnight, pagefault (pagefault@zsnes.com) and
- Kris Bleakley
- Ported from x86 assembler to C by sanmaiwashi
-
- SPC7110 and RTC C++ emulator code
- (c) Copyright 2002 Matthew Kendora with research by
- zsKnight, John Weidman, and Dark Force
-
- S-DD1 C emulator code
- (c) Copyright 2003 Brad Jorsch with research by
- Andreas Naive and John Weidman
-
- S-RTC C emulator code
- (c) Copyright 2001 John Weidman
-
- ST010 C++ emulator code
- (c) Copyright 2003 Feather, Kris Bleakley, John Weidman and Matthew Kendora
-
- Super FX x86 assembler emulator code
- (c) Copyright 1998 - 2003 zsKnight, _Demo_, and pagefault
-
- Super FX C emulator code
- (c) Copyright 1997 - 1999 Ivar, Gary Henderson and John Weidman
-
-
- SH assembler code partly based on x86 assembler code
- (c) Copyright 2002 - 2004 Marcus Comstedt (marcus@mc.pp.se)
-
- (c) Copyright 2014 - 2016 Daniel De Matteis. (UNDER NO CIRCUMSTANCE
- WILL COMMERCIAL RIGHTS EVER BE APPROPRIATED TO ANY PARTY)
-
- Specific ports contains the works of other authors. See headers in
- individual files.
-
- Snes9x homepage: http://www.snes9x.com
-
- Permission to use, copy, modify and distribute Snes9x in both binary and
- source form, for non-commercial purposes, is hereby granted without fee,
- providing that this license information and copyright notice appear with
- all copies and any derived work.
-
- This software is provided 'as-is', without any express or implied
- warranty. In no event shall the authors be held liable for any damages
- arising from the use of this software.
-
- Snes9x is freeware for PERSONAL USE only. Commercial users should
- seek permission of the copyright holders first. Commercial use includes
- charging money for Snes9x or software derived from Snes9x.
-
- The copyright holders request that bug fixes and improvements to the code
- should be forwarded to them so everyone can benefit from the modifications
- in future versions.
-
- Super NES and Super Nintendo Entertainment System are trademarks of
- Nintendo Co., Limited and its subsidiary companies.
-*******************************************************************************/
-
+#include "../copyright"
uint16_t DSP2Op09Word1 = 0;
uint16_t DSP2Op09Word2 = 0;
@@ -226,29 +136,19 @@ int DSP2Op0DInLen = 0;
void DSP2_Op0D()
{
- // Overload's algorithm - use this unless doing hardware testing
-
- // One note: the HW can do odd byte scaling but since we divide
- // by two to get the count of bytes this won't work well for
- // odd byte scaling (in any of the current algorithm implementations).
- // So far I haven't seen Dungeon Master use it.
- // If it does we can adjust the parameters and code to work with it
+ // (Modified) Overload's algorithm - use this unless doing hardware testing
int i;
- int pixel_offset;
- uint8_t pixelarray[512];
- for (i = 0; i < DSP2Op0DOutLen * 2; i++)
+ for(i = 0 ; i < DSP2Op0DOutLen ; i++)
{
- pixel_offset = (i * DSP2Op0DInLen) / DSP2Op0DOutLen;
- if ((pixel_offset & 1) == 0)
- pixelarray[i] = DSP1.parameters[pixel_offset >> 1] >> 4;
- else
- pixelarray[i] = DSP1.parameters[pixel_offset >> 1] & 0x0f;
+ int j = i << 1;
+ int pixel_offset_low = ((j * DSP2Op0DInLen) / DSP2Op0DOutLen) >> 1;
+ int pixel_offset_high = (((j + 1) * DSP2Op0DInLen) / DSP2Op0DOutLen) >> 1;
+ uint8_t pixel_low = DSP1.parameters[pixel_offset_low] >> 4;
+ uint8_t pixel_high = DSP1.parameters[pixel_offset_high] & 0x0f;
+ DSP1.output[i] = (pixel_low << 4) | pixel_high;
}
-
- for (i = 0; i < DSP2Op0DOutLen; i++)
- DSP1.output[i] = (pixelarray[i << 1] << 4) | pixelarray[(i << 1) + 1];
}
#else
@@ -298,45 +198,3 @@ void DSP2_Op0D()
}
#endif
-
-#if 0 // Probably no reason to use this code - it's not quite bit accurate and it doesn't look as good as Overload's algorithm
-
-void DSP2_Op0D()
-{
- // Float implementation of Neviksti's algorithm
- // This is the right algorithm to match the DSP2 bits but the precision
- // of the PC float does not match the precision of the fixed point math
- // on the DSP2 causing occasional one off data mismatches (which should
- // be no problem because its just a one pixel difference in a scaled image
- // to be displayed).
-
- float multiplier;
- float pixloc;
- int i, j;
- uint8_t pixelarray[512];
-
- if (DSP2Op0DInLen <= DSP2Op0DOutLen)
- multiplier = (float) 1.0;
- else
- multiplier = (float)((DSP2Op0DInLen * 2.0) / (DSP2Op0DOutLen * 2.0 + 1.0));
-
- pixloc = 0.0;
- for (i = 0; i < DSP2Op0DOutLen * 2; i++)
- {
- // j = (int)(i * multiplier);
- j = (int) pixloc;
-
- if (j & 1)
- pixelarray[i] = DSP1.parameters[j >> 1] & 0x0f;
- else
- pixelarray[i] = (DSP1.parameters[j >> 1] & 0xf0) >> 4;
-
- pixloc += multiplier; // use an add in the loop instead of multiply to increase loop speed
- }
-
- for (i = 0; i < DSP2Op0DOutLen; i++)
- DSP1.output[i] = (pixelarray[i << 1] << 4) | pixelarray[(i << 1) + 1];
-}
-
-#endif
-
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