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Diffstat (limited to 'plugins/gme/game-music-emu-0.6.0/gme/Spc_Dsp.cpp')
-rw-r--r--plugins/gme/game-music-emu-0.6.0/gme/Spc_Dsp.cpp703
1 files changed, 703 insertions, 0 deletions
diff --git a/plugins/gme/game-music-emu-0.6.0/gme/Spc_Dsp.cpp b/plugins/gme/game-music-emu-0.6.0/gme/Spc_Dsp.cpp
new file mode 100644
index 00000000..65f83fe5
--- /dev/null
+++ b/plugins/gme/game-music-emu-0.6.0/gme/Spc_Dsp.cpp
@@ -0,0 +1,703 @@
+// Game_Music_Emu 0.5.5. http://www.slack.net/~ant/
+
+#include "Spc_Dsp.h"
+
+#include "blargg_endian.h"
+#include <string.h>
+
+/* Copyright (C) 2007 Shay Green. This module is free software; you
+can redistribute it and/or modify it under the terms of the GNU Lesser
+General Public License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version. This
+module 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 Lesser General Public License for more
+details. You should have received a copy of the GNU Lesser General Public
+License along with this module; if not, write to the Free Software Foundation,
+Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
+
+#include "blargg_source.h"
+
+#ifdef BLARGG_ENABLE_OPTIMIZER
+ #include BLARGG_ENABLE_OPTIMIZER
+#endif
+
+#if INT_MAX < 0x7FFFFFFF
+ #error "Requires that int type have at least 32 bits"
+#endif
+
+
+// TODO: add to blargg_endian.h
+#define GET_LE16SA( addr ) ((BOOST::int16_t) GET_LE16( addr ))
+#define GET_LE16A( addr ) GET_LE16( addr )
+#define SET_LE16A( addr, data ) SET_LE16( addr, data )
+
+static BOOST::uint8_t const initial_regs [Spc_Dsp::register_count] =
+{
+ 0x45,0x8B,0x5A,0x9A,0xE4,0x82,0x1B,0x78,0x00,0x00,0xAA,0x96,0x89,0x0E,0xE0,0x80,
+ 0x2A,0x49,0x3D,0xBA,0x14,0xA0,0xAC,0xC5,0x00,0x00,0x51,0xBB,0x9C,0x4E,0x7B,0xFF,
+ 0xF4,0xFD,0x57,0x32,0x37,0xD9,0x42,0x22,0x00,0x00,0x5B,0x3C,0x9F,0x1B,0x87,0x9A,
+ 0x6F,0x27,0xAF,0x7B,0xE5,0x68,0x0A,0xD9,0x00,0x00,0x9A,0xC5,0x9C,0x4E,0x7B,0xFF,
+ 0xEA,0x21,0x78,0x4F,0xDD,0xED,0x24,0x14,0x00,0x00,0x77,0xB1,0xD1,0x36,0xC1,0x67,
+ 0x52,0x57,0x46,0x3D,0x59,0xF4,0x87,0xA4,0x00,0x00,0x7E,0x44,0x9C,0x4E,0x7B,0xFF,
+ 0x75,0xF5,0x06,0x97,0x10,0xC3,0x24,0xBB,0x00,0x00,0x7B,0x7A,0xE0,0x60,0x12,0x0F,
+ 0xF7,0x74,0x1C,0xE5,0x39,0x3D,0x73,0xC1,0x00,0x00,0x7A,0xB3,0xFF,0x4E,0x7B,0xFF
+};
+
+// if ( io < -32768 ) io = -32768;
+// if ( io > 32767 ) io = 32767;
+#define CLAMP16( io )\
+{\
+ if ( (int16_t) io != io )\
+ io = (io >> 31) ^ 0x7FFF;\
+}
+
+// Access global DSP register
+#define REG(n) m.regs [r_##n]
+
+// Access voice DSP register
+#define VREG(r,n) r [v_##n]
+
+#define WRITE_SAMPLES( l, r, out ) \
+{\
+ out [0] = l;\
+ out [1] = r;\
+ out += 2;\
+ if ( out >= m.out_end )\
+ {\
+ check( out == m.out_end );\
+ check( m.out_end != &m.extra [extra_size] || \
+ (m.extra <= m.out_begin && m.extra < &m.extra [extra_size]) );\
+ out = m.extra;\
+ m.out_end = &m.extra [extra_size];\
+ }\
+}\
+
+void Spc_Dsp::set_output( sample_t* out, int size )
+{
+ require( (size & 1) == 0 ); // must be even
+ if ( !out )
+ {
+ out = m.extra;
+ size = extra_size;
+ }
+ m.out_begin = out;
+ m.out = out;
+ m.out_end = out + size;
+}
+
+// Volume registers and efb are signed! Easy to forget int8_t cast.
+// Prefixes are to avoid accidental use of locals with same names.
+
+// Interleved gauss table (to improve cache coherency)
+// interleved_gauss [i] = gauss [(i & 1) * 256 + 255 - (i >> 1 & 0xFF)]
+static short const interleved_gauss [512] =
+{
+ 370,1305, 366,1305, 362,1304, 358,1304, 354,1304, 351,1304, 347,1304, 343,1303,
+ 339,1303, 336,1303, 332,1302, 328,1302, 325,1301, 321,1300, 318,1300, 314,1299,
+ 311,1298, 307,1297, 304,1297, 300,1296, 297,1295, 293,1294, 290,1293, 286,1292,
+ 283,1291, 280,1290, 276,1288, 273,1287, 270,1286, 267,1284, 263,1283, 260,1282,
+ 257,1280, 254,1279, 251,1277, 248,1275, 245,1274, 242,1272, 239,1270, 236,1269,
+ 233,1267, 230,1265, 227,1263, 224,1261, 221,1259, 218,1257, 215,1255, 212,1253,
+ 210,1251, 207,1248, 204,1246, 201,1244, 199,1241, 196,1239, 193,1237, 191,1234,
+ 188,1232, 186,1229, 183,1227, 180,1224, 178,1221, 175,1219, 173,1216, 171,1213,
+ 168,1210, 166,1207, 163,1205, 161,1202, 159,1199, 156,1196, 154,1193, 152,1190,
+ 150,1186, 147,1183, 145,1180, 143,1177, 141,1174, 139,1170, 137,1167, 134,1164,
+ 132,1160, 130,1157, 128,1153, 126,1150, 124,1146, 122,1143, 120,1139, 118,1136,
+ 117,1132, 115,1128, 113,1125, 111,1121, 109,1117, 107,1113, 106,1109, 104,1106,
+ 102,1102, 100,1098, 99,1094, 97,1090, 95,1086, 94,1082, 92,1078, 90,1074,
+ 89,1070, 87,1066, 86,1061, 84,1057, 83,1053, 81,1049, 80,1045, 78,1040,
+ 77,1036, 76,1032, 74,1027, 73,1023, 71,1019, 70,1014, 69,1010, 67,1005,
+ 66,1001, 65, 997, 64, 992, 62, 988, 61, 983, 60, 978, 59, 974, 58, 969,
+ 56, 965, 55, 960, 54, 955, 53, 951, 52, 946, 51, 941, 50, 937, 49, 932,
+ 48, 927, 47, 923, 46, 918, 45, 913, 44, 908, 43, 904, 42, 899, 41, 894,
+ 40, 889, 39, 884, 38, 880, 37, 875, 36, 870, 36, 865, 35, 860, 34, 855,
+ 33, 851, 32, 846, 32, 841, 31, 836, 30, 831, 29, 826, 29, 821, 28, 816,
+ 27, 811, 27, 806, 26, 802, 25, 797, 24, 792, 24, 787, 23, 782, 23, 777,
+ 22, 772, 21, 767, 21, 762, 20, 757, 20, 752, 19, 747, 19, 742, 18, 737,
+ 17, 732, 17, 728, 16, 723, 16, 718, 15, 713, 15, 708, 15, 703, 14, 698,
+ 14, 693, 13, 688, 13, 683, 12, 678, 12, 674, 11, 669, 11, 664, 11, 659,
+ 10, 654, 10, 649, 10, 644, 9, 640, 9, 635, 9, 630, 8, 625, 8, 620,
+ 8, 615, 7, 611, 7, 606, 7, 601, 6, 596, 6, 592, 6, 587, 6, 582,
+ 5, 577, 5, 573, 5, 568, 5, 563, 4, 559, 4, 554, 4, 550, 4, 545,
+ 4, 540, 3, 536, 3, 531, 3, 527, 3, 522, 3, 517, 2, 513, 2, 508,
+ 2, 504, 2, 499, 2, 495, 2, 491, 2, 486, 1, 482, 1, 477, 1, 473,
+ 1, 469, 1, 464, 1, 460, 1, 456, 1, 451, 1, 447, 1, 443, 1, 439,
+ 0, 434, 0, 430, 0, 426, 0, 422, 0, 418, 0, 414, 0, 410, 0, 405,
+ 0, 401, 0, 397, 0, 393, 0, 389, 0, 385, 0, 381, 0, 378, 0, 374,
+};
+
+
+//// Counters
+
+#define RATE( rate, div )\
+ (rate >= div ? rate / div * 8 - 1 : rate - 1)
+
+static unsigned const counter_mask [32] =
+{
+ RATE( 2,2), RATE(2048,4), RATE(1536,3),
+ RATE(1280,5), RATE(1024,4), RATE( 768,3),
+ RATE( 640,5), RATE( 512,4), RATE( 384,3),
+ RATE( 320,5), RATE( 256,4), RATE( 192,3),
+ RATE( 160,5), RATE( 128,4), RATE( 96,3),
+ RATE( 80,5), RATE( 64,4), RATE( 48,3),
+ RATE( 40,5), RATE( 32,4), RATE( 24,3),
+ RATE( 20,5), RATE( 16,4), RATE( 12,3),
+ RATE( 10,5), RATE( 8,4), RATE( 6,3),
+ RATE( 5,5), RATE( 4,4), RATE( 3,3),
+ RATE( 2,4),
+ RATE( 1,4)
+};
+#undef RATE
+
+inline void Spc_Dsp::init_counter()
+{
+ // counters start out with this synchronization
+ m.counters [0] = 1;
+ m.counters [1] = 0;
+ m.counters [2] = -0x20u;
+ m.counters [3] = 0x0B;
+
+ int n = 2;
+ for ( int i = 1; i < 32; i++ )
+ {
+ m.counter_select [i] = &m.counters [n];
+ if ( !--n )
+ n = 3;
+ }
+ m.counter_select [ 0] = &m.counters [0];
+ m.counter_select [30] = &m.counters [2];
+}
+
+inline void Spc_Dsp::run_counter( int i )
+{
+ int n = m.counters [i];
+ if ( !(n-- & 7) )
+ n -= 6 - i;
+ m.counters [i] = n;
+}
+
+#define READ_COUNTER( rate )\
+ (*m.counter_select [rate] & counter_mask [rate])
+
+
+//// Emulation
+
+void Spc_Dsp::run( int clock_count )
+{
+ int new_phase = m.phase + clock_count;
+ int count = new_phase >> 5;
+ m.phase = new_phase & 31;
+ if ( !count )
+ return;
+
+ uint8_t* const ram = m.ram;
+ uint8_t const* const dir = &ram [REG(dir) * 0x100];
+ int const slow_gaussian = (REG(pmon) >> 1) | REG(non);
+ int const noise_rate = REG(flg) & 0x1F;
+
+ // Global volume
+ int mvoll = (int8_t) REG(mvoll);
+ int mvolr = (int8_t) REG(mvolr);
+ if ( mvoll * mvolr < m.surround_threshold )
+ mvoll = -mvoll; // eliminate surround
+
+ do
+ {
+ // KON/KOFF reading
+ if ( (m.every_other_sample ^= 1) != 0 )
+ {
+ m.new_kon &= ~m.kon;
+ m.kon = m.new_kon;
+ m.t_koff = REG(koff);
+ }
+
+ run_counter( 1 );
+ run_counter( 2 );
+ run_counter( 3 );
+
+ // Noise
+ if ( !READ_COUNTER( noise_rate ) )
+ {
+ int feedback = (m.noise << 13) ^ (m.noise << 14);
+ m.noise = (feedback & 0x4000) ^ (m.noise >> 1);
+ }
+
+ // Voices
+ int pmon_input = 0;
+ int main_out_l = 0;
+ int main_out_r = 0;
+ int echo_out_l = 0;
+ int echo_out_r = 0;
+ voice_t* v = m.voices;
+ uint8_t* v_regs = m.regs;
+ int vbit = 1;
+ do
+ {
+ #define SAMPLE_PTR(i) GET_LE16A( &dir [VREG(v_regs,srcn) * 4 + i * 2] )
+
+ int brr_header = ram [v->brr_addr];
+ int kon_delay = v->kon_delay;
+
+ // Pitch
+ int pitch = GET_LE16A( &VREG(v_regs,pitchl) ) & 0x3FFF;
+ if ( REG(pmon) & vbit )
+ pitch += ((pmon_input >> 5) * pitch) >> 10;
+
+ // KON phases
+ if ( --kon_delay >= 0 )
+ {
+ v->kon_delay = kon_delay;
+
+ // Get ready to start BRR decoding on next sample
+ if ( kon_delay == 4 )
+ {
+ v->brr_addr = SAMPLE_PTR( 0 );
+ v->brr_offset = 1;
+ v->buf_pos = v->buf;
+ brr_header = 0; // header is ignored on this sample
+ }
+
+ // Envelope is never run during KON
+ v->env = 0;
+ v->hidden_env = 0;
+
+ // Disable BRR decoding until last three samples
+ v->interp_pos = (kon_delay & 3 ? 0x4000 : 0);
+
+ // Pitch is never added during KON
+ pitch = 0;
+ }
+
+ int env = v->env;
+
+ // Gaussian interpolation
+ {
+ int output = 0;
+ VREG(v_regs,envx) = (uint8_t) (env >> 4);
+ if ( env )
+ {
+ // Make pointers into gaussian based on fractional position between samples
+ int offset = (unsigned) v->interp_pos >> 3 & 0x1FE;
+ short const* fwd = interleved_gauss + offset;
+ short const* rev = interleved_gauss + 510 - offset; // mirror left half of gaussian
+
+ int const* in = &v->buf_pos [(unsigned) v->interp_pos >> 12];
+
+ if ( !(slow_gaussian & vbit) ) // 99%
+ {
+ // Faster approximation when exact sample value isn't necessary for pitch mod
+ output = (fwd [0] * in [0] +
+ fwd [1] * in [1] +
+ rev [1] * in [2] +
+ rev [0] * in [3]) >> 11;
+ output = (output * env) >> 11;
+ }
+ else
+ {
+ output = (int16_t) (m.noise * 2);
+ if ( !(REG(non) & vbit) )
+ {
+ output = (fwd [0] * in [0]) >> 11;
+ output += (fwd [1] * in [1]) >> 11;
+ output += (rev [1] * in [2]) >> 11;
+ output = (int16_t) output;
+ output += (rev [0] * in [3]) >> 11;
+
+ CLAMP16( output );
+ output &= ~1;
+ }
+ output = (output * env) >> 11 & ~1;
+ }
+
+ // Output
+ int l = output * v->volume [0];
+ int r = output * v->volume [1];
+
+ main_out_l += l;
+ main_out_r += r;
+
+ if ( REG(eon) & vbit )
+ {
+ echo_out_l += l;
+ echo_out_r += r;
+ }
+ }
+
+ pmon_input = output;
+ VREG(v_regs,outx) = (uint8_t) (output >> 8);
+ }
+
+ // Soft reset or end of sample
+ if ( REG(flg) & 0x80 || (brr_header & 3) == 1 )
+ {
+ v->env_mode = env_release;
+ env = 0;
+ }
+
+ if ( m.every_other_sample )
+ {
+ // KOFF
+ if ( m.t_koff & vbit )
+ v->env_mode = env_release;
+
+ // KON
+ if ( m.kon & vbit )
+ {
+ v->kon_delay = 5;
+ v->env_mode = env_attack;
+ REG(endx) &= ~vbit;
+ }
+ }
+
+ // Envelope
+ if ( !v->kon_delay )
+ {
+ if ( v->env_mode == env_release ) // 97%
+ {
+ env -= 0x8;
+ v->env = env;
+ if ( env <= 0 )
+ {
+ v->env = 0;
+ goto skip_brr; // no BRR decoding for you!
+ }
+ }
+ else // 3%
+ {
+ int rate;
+ int const adsr0 = VREG(v_regs,adsr0);
+ int env_data = VREG(v_regs,adsr1);
+ if ( adsr0 >= 0x80 ) // 97% ADSR
+ {
+ if ( v->env_mode > env_decay ) // 89%
+ {
+ env--;
+ env -= env >> 8;
+ rate = env_data & 0x1F;
+
+ // optimized handling
+ v->hidden_env = env;
+ if ( READ_COUNTER( rate ) )
+ goto exit_env;
+ v->env = env;
+ goto exit_env;
+ }
+ else if ( v->env_mode == env_decay )
+ {
+ env--;
+ env -= env >> 8;
+ rate = (adsr0 >> 3 & 0x0E) + 0x10;
+ }
+ else // env_attack
+ {
+ rate = (adsr0 & 0x0F) * 2 + 1;
+ env += rate < 31 ? 0x20 : 0x400;
+ }
+ }
+ else // GAIN
+ {
+ int mode;
+ env_data = VREG(v_regs,gain);
+ mode = env_data >> 5;
+ if ( mode < 4 ) // direct
+ {
+ env = env_data * 0x10;
+ rate = 31;
+ }
+ else
+ {
+ rate = env_data & 0x1F;
+ if ( mode == 4 ) // 4: linear decrease
+ {
+ env -= 0x20;
+ }
+ else if ( mode < 6 ) // 5: exponential decrease
+ {
+ env--;
+ env -= env >> 8;
+ }
+ else // 6,7: linear increase
+ {
+ env += 0x20;
+ if ( mode > 6 && (unsigned) v->hidden_env >= 0x600 )
+ env += 0x8 - 0x20; // 7: two-slope linear increase
+ }
+ }
+ }
+
+ // Sustain level
+ if ( (env >> 8) == (env_data >> 5) && v->env_mode == env_decay )
+ v->env_mode = env_sustain;
+
+ v->hidden_env = env;
+
+ // unsigned cast because linear decrease going negative also triggers this
+ if ( (unsigned) env > 0x7FF )
+ {
+ env = (env < 0 ? 0 : 0x7FF);
+ if ( v->env_mode == env_attack )
+ v->env_mode = env_decay;
+ }
+
+ if ( !READ_COUNTER( rate ) )
+ v->env = env; // nothing else is controlled by the counter
+ }
+ }
+ exit_env:
+
+ {
+ // Apply pitch
+ int old_pos = v->interp_pos;
+ int interp_pos = (old_pos & 0x3FFF) + pitch;
+ if ( interp_pos > 0x7FFF )
+ interp_pos = 0x7FFF;
+ v->interp_pos = interp_pos;
+
+ // BRR decode if necessary
+ if ( old_pos >= 0x4000 )
+ {
+ // Arrange the four input nybbles in 0xABCD order for easy decoding
+ int nybbles = ram [(v->brr_addr + v->brr_offset) & 0xFFFF] * 0x100 +
+ ram [(v->brr_addr + v->brr_offset + 1) & 0xFFFF];
+
+ // Advance read position
+ int const brr_block_size = 9;
+ int brr_offset = v->brr_offset;
+ if ( (brr_offset += 2) >= brr_block_size )
+ {
+ // Next BRR block
+ int brr_addr = (v->brr_addr + brr_block_size) & 0xFFFF;
+ assert( brr_offset == brr_block_size );
+ if ( brr_header & 1 )
+ {
+ brr_addr = SAMPLE_PTR( 1 );
+ if ( !v->kon_delay )
+ REG(endx) |= vbit;
+ }
+ v->brr_addr = brr_addr;
+ brr_offset = 1;
+ }
+ v->brr_offset = brr_offset;
+
+ // Decode
+
+ // 0: >>1 1: <<0 2: <<1 ... 12: <<11 13-15: >>4 <<11
+ static unsigned char const shifts [16 * 2] = {
+ 13,12,12,12,12,12,12,12,12,12,12, 12, 12, 16, 16, 16,
+ 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 11, 11, 11
+ };
+ int const scale = brr_header >> 4;
+ int const right_shift = shifts [scale];
+ int const left_shift = shifts [scale + 16];
+
+ // Write to next four samples in circular buffer
+ int* pos = v->buf_pos;
+ int* end;
+
+ // Decode four samples
+ for ( end = pos + 4; pos < end; pos++, nybbles <<= 4 )
+ {
+ // Extract upper nybble and scale appropriately
+ int s = ((int16_t) nybbles >> right_shift) << left_shift;
+
+ // Apply IIR filter (8 is the most commonly used)
+ int const filter = brr_header & 0x0C;
+ int const p1 = pos [brr_buf_size - 1];
+ int const p2 = pos [brr_buf_size - 2] >> 1;
+ if ( filter >= 8 )
+ {
+ s += p1;
+ s -= p2;
+ if ( filter == 8 ) // s += p1 * 0.953125 - p2 * 0.46875
+ {
+ s += p2 >> 4;
+ s += (p1 * -3) >> 6;
+ }
+ else // s += p1 * 0.8984375 - p2 * 0.40625
+ {
+ s += (p1 * -13) >> 7;
+ s += (p2 * 3) >> 4;
+ }
+ }
+ else if ( filter ) // s += p1 * 0.46875
+ {
+ s += p1 >> 1;
+ s += (-p1) >> 5;
+ }
+
+ // Adjust and write sample
+ CLAMP16( s );
+ s = (int16_t) (s * 2);
+ pos [brr_buf_size] = pos [0] = s; // second copy simplifies wrap-around
+ }
+
+ if ( pos >= &v->buf [brr_buf_size] )
+ pos = v->buf;
+ v->buf_pos = pos;
+ }
+ }
+skip_brr:
+ // Next voice
+ vbit <<= 1;
+ v_regs += 0x10;
+ v++;
+ }
+ while ( vbit < 0x100 );
+
+ // Echo position
+ int echo_offset = m.echo_offset;
+ uint8_t* const echo_ptr = &ram [(REG(esa) * 0x100 + echo_offset) & 0xFFFF];
+ if ( !echo_offset )
+ m.echo_length = (REG(edl) & 0x0F) * 0x800;
+ echo_offset += 4;
+ if ( echo_offset >= m.echo_length )
+ echo_offset = 0;
+ m.echo_offset = echo_offset;
+
+ // FIR
+ int echo_in_l = GET_LE16SA( echo_ptr + 0 );
+ int echo_in_r = GET_LE16SA( echo_ptr + 2 );
+
+ int (*echo_hist_pos) [2] = m.echo_hist_pos;
+ if ( ++echo_hist_pos >= &m.echo_hist [echo_hist_size] )
+ echo_hist_pos = m.echo_hist;
+ m.echo_hist_pos = echo_hist_pos;
+
+ echo_hist_pos [0] [0] = echo_hist_pos [8] [0] = echo_in_l;
+ echo_hist_pos [0] [1] = echo_hist_pos [8] [1] = echo_in_r;
+
+ #define CALC_FIR_( i, in ) ((in) * (int8_t) REG(fir + i * 0x10))
+ echo_in_l = CALC_FIR_( 7, echo_in_l );
+ echo_in_r = CALC_FIR_( 7, echo_in_r );
+
+ #define CALC_FIR( i, ch ) CALC_FIR_( i, echo_hist_pos [i + 1] [ch] )
+ #define DO_FIR( i )\
+ echo_in_l += CALC_FIR( i, 0 );\
+ echo_in_r += CALC_FIR( i, 1 );
+ DO_FIR( 0 );
+ DO_FIR( 1 );
+ DO_FIR( 2 );
+ #if defined (__MWERKS__) && __MWERKS__ < 0x3200
+ __eieio(); // keeps compiler from stupidly "caching" things in memory
+ #endif
+ DO_FIR( 3 );
+ DO_FIR( 4 );
+ DO_FIR( 5 );
+ DO_FIR( 6 );
+
+ // Echo out
+ if ( !(REG(flg) & 0x20) )
+ {
+ int l = (echo_out_l >> 7) + ((echo_in_l * (int8_t) REG(efb)) >> 14);
+ int r = (echo_out_r >> 7) + ((echo_in_r * (int8_t) REG(efb)) >> 14);
+
+ // just to help pass more validation tests
+ #if SPC_MORE_ACCURACY
+ l &= ~1;
+ r &= ~1;
+ #endif
+
+ CLAMP16( l );
+ CLAMP16( r );
+
+ SET_LE16A( echo_ptr + 0, l );
+ SET_LE16A( echo_ptr + 2, r );
+ }
+
+ // Sound out
+ int l = (main_out_l * mvoll + echo_in_l * (int8_t) REG(evoll)) >> 14;
+ int r = (main_out_r * mvolr + echo_in_r * (int8_t) REG(evolr)) >> 14;
+
+ CLAMP16( l );
+ CLAMP16( r );
+
+ if ( (REG(flg) & 0x40) )
+ {
+ l = 0;
+ r = 0;
+ }
+
+ sample_t* out = m.out;
+ WRITE_SAMPLES( l, r, out );
+ m.out = out;
+ }
+ while ( --count );
+}
+
+
+//// Setup
+
+void Spc_Dsp::mute_voices( int mask )
+{
+ m.mute_mask = mask;
+ for ( int i = 0; i < voice_count; i++ )
+ {
+ m.voices [i].enabled = (mask >> i & 1) - 1;
+ update_voice_vol( i * 0x10 );
+ }
+}
+
+void Spc_Dsp::init( void* ram_64k )
+{
+ m.ram = (uint8_t*) ram_64k;
+ mute_voices( 0 );
+ disable_surround( false );
+ set_output( 0, 0 );
+ reset();
+
+ #ifndef NDEBUG
+ // be sure this sign-extends
+ assert( (int16_t) 0x8000 == -0x8000 );
+
+ // be sure right shift preserves sign
+ assert( (-1 >> 1) == -1 );
+
+ // check clamp macro
+ int i;
+ i = +0x8000; CLAMP16( i ); assert( i == +0x7FFF );
+ i = -0x8001; CLAMP16( i ); assert( i == -0x8000 );
+
+ blargg_verify_byte_order();
+ #endif
+}
+
+void Spc_Dsp::soft_reset_common()
+{
+ require( m.ram ); // init() must have been called already
+
+ m.noise = 0x4000;
+ m.echo_hist_pos = m.echo_hist;
+ m.every_other_sample = 1;
+ m.echo_offset = 0;
+ m.phase = 0;
+
+ init_counter();
+}
+
+void Spc_Dsp::soft_reset()
+{
+ REG(flg) = 0xE0;
+ soft_reset_common();
+}
+
+void Spc_Dsp::load( uint8_t const regs [register_count] )
+{
+ memcpy( m.regs, regs, sizeof m.regs );
+ memset( &m.regs [register_count], 0, offsetof (state_t,ram) - register_count );
+
+ // Internal state
+ int i;
+ for ( i = voice_count; --i >= 0; )
+ {
+ voice_t& v = m.voices [i];
+ v.brr_offset = 1;
+ v.buf_pos = v.buf;
+ }
+ m.new_kon = REG(kon);
+
+ mute_voices( m.mute_mask );
+ soft_reset_common();
+}
+
+void Spc_Dsp::reset() { load( initial_regs ); }