/* 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. * */ #include "audio/softsynth/cms.h" #include "audio/null.h" #include "common/textconsole.h" #include "common/translation.h" #include "common/debug.h" // CMS/Gameblaster Emulation taken from DosBox #define LEFT 0x00 #define RIGHT 0x01 static const byte envelope[8][64] = { /* zero amplitude */ { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, /* maximum amplitude */ {15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15, 15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15, 15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15, 15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15 }, /* single decay */ {15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, /* repetitive decay */ {15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 }, /* single triangular */ { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15, 15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, /* repetitive triangular */ { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15, 15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15, 15,14,13,12,11,10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 }, /* single attack */ { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }, /* repetitive attack */ { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,15 } }; static const int amplitude_lookup[16] = { 0*32767/16, 1*32767/16, 2*32767/16, 3*32767/16, 4*32767/16, 5*32767/16, 6*32767/16, 7*32767/16, 8*32767/16, 9*32767/16, 10*32767/16, 11*32767/16, 12*32767/16, 13*32767/16, 14*32767/16, 15*32767/16 }; void CMSEmulator::portWrite(int port, int val) { switch (port) { case 0x220: portWriteIntern(0, 1, val); break; case 0x221: _saa1099[0].selected_reg = val & 0x1f; if (_saa1099[0].selected_reg == 0x18 || _saa1099[0].selected_reg == 0x19) { /* clock the envelope channels */ if (_saa1099[0].env_clock[0]) envelope(0, 0); if (_saa1099[0].env_clock[1]) envelope(0, 1); } break; case 0x222: portWriteIntern(1, 1, val); break; case 0x223: _saa1099[1].selected_reg = val & 0x1f; if (_saa1099[1].selected_reg == 0x18 || _saa1099[1].selected_reg == 0x19) { /* clock the envelope channels */ if (_saa1099[1].env_clock[0]) envelope(1, 0); if (_saa1099[1].env_clock[1]) envelope(1, 1); } break; default: warning("CMSEmulator got port: 0x%X", port); break; } } void CMSEmulator::readBuffer(int16 *buffer, const int numSamples) { update(0, &buffer[0], numSamples); update(1, &buffer[0], numSamples); } void CMSEmulator::envelope(int chip, int ch) { SAA1099 *saa = &_saa1099[chip]; if (saa->env_enable[ch]) { int step, mode, mask; mode = saa->env_mode[ch]; /* step from 0..63 and then loop in steps 32..63 */ step = saa->env_step[ch] = ((saa->env_step[ch] + 1) & 0x3f) | (saa->env_step[ch] & 0x20); mask = 15; if (saa->env_bits[ch]) mask &= ~1; /* 3 bit resolution, mask LSB */ saa->channels[ch*3+0].envelope[ LEFT] = saa->channels[ch*3+1].envelope[ LEFT] = saa->channels[ch*3+2].envelope[ LEFT] = ::envelope[mode][step] & mask; if (saa->env_reverse_right[ch] & 0x01) { saa->channels[ch*3+0].envelope[RIGHT] = saa->channels[ch*3+1].envelope[RIGHT] = saa->channels[ch*3+2].envelope[RIGHT] = (15 - ::envelope[mode][step]) & mask; } else { saa->channels[ch*3+0].envelope[RIGHT] = saa->channels[ch*3+1].envelope[RIGHT] = saa->channels[ch*3+2].envelope[RIGHT] = ::envelope[mode][step] & mask; } } else { /* envelope mode off, set all envelope factors to 16 */ saa->channels[ch*3+0].envelope[ LEFT] = saa->channels[ch*3+1].envelope[ LEFT] = saa->channels[ch*3+2].envelope[ LEFT] = saa->channels[ch*3+0].envelope[RIGHT] = saa->channels[ch*3+1].envelope[RIGHT] = saa->channels[ch*3+2].envelope[RIGHT] = 16; } } void CMSEmulator::update(int chip, int16 *buffer, int length) { struct SAA1099 *saa = &_saa1099[chip]; int j, ch; if (chip == 0) { memset(buffer, 0, sizeof(int16)*length*2); } /* if the channels are disabled we're done */ if (!saa->all_ch_enable) { return; } for (ch = 0; ch < 2; ch++) { switch (saa->noise_params[ch]) { case 0: saa->noise[ch].freq = 31250.0 * 2; break; case 1: saa->noise[ch].freq = 15625.0 * 2; break; case 2: saa->noise[ch].freq = 7812.5 * 2; break; case 3: saa->noise[ch].freq = saa->channels[ch * 3].freq; break; } } /* fill all data needed */ for (j = 0; j < length; ++j) { int output_l = 0, output_r = 0; /* for each channel */ for (ch = 0; ch < 6; ch++) { if (saa->channels[ch].freq == 0.0) saa->channels[ch].freq = (double)((2 * 15625) << saa->channels[ch].octave) / (511.0 - (double)saa->channels[ch].frequency); /* check the actual position in the square wave */ saa->channels[ch].counter -= saa->channels[ch].freq; while (saa->channels[ch].counter < 0) { /* calculate new frequency now after the half wave is updated */ saa->channels[ch].freq = (double)((2 * 15625) << saa->channels[ch].octave) / (511.0 - (double)saa->channels[ch].frequency); saa->channels[ch].counter += _sampleRate; saa->channels[ch].level ^= 1; /* eventually clock the envelope counters */ if (ch == 1 && saa->env_clock[0] == 0) envelope(chip, 0); if (ch == 4 && saa->env_clock[1] == 0) envelope(chip, 1); } /* if the noise is enabled */ if (saa->channels[ch].noise_enable) { /* if the noise level is high (noise 0: chan 0-2, noise 1: chan 3-5) */ if (saa->noise[ch/3].level & 1) { /* subtract to avoid overflows, also use only half amplitude */ output_l -= saa->channels[ch].amplitude[ LEFT] * saa->channels[ch].envelope[ LEFT] / 16 / 2; output_r -= saa->channels[ch].amplitude[RIGHT] * saa->channels[ch].envelope[RIGHT] / 16 / 2; } } /* if the square wave is enabled */ if (saa->channels[ch].freq_enable) { /* if the channel level is high */ if (saa->channels[ch].level & 1) { output_l += saa->channels[ch].amplitude[ LEFT] * saa->channels[ch].envelope[ LEFT] / 16; output_r += saa->channels[ch].amplitude[RIGHT] * saa->channels[ch].envelope[RIGHT] / 16; } } } for (ch = 0; ch < 2; ch++) { /* check the actual position in noise generator */ saa->noise[ch].counter -= saa->noise[ch].freq; while (saa->noise[ch].counter < 0) { saa->noise[ch].counter += _sampleRate; if (((saa->noise[ch].level & 0x4000) == 0) == ((saa->noise[ch].level & 0x0040) == 0) ) saa->noise[ch].level = (saa->noise[ch].level << 1) | 1; else saa->noise[ch].level <<= 1; } } /* write sound data to the buffer */ buffer[j*2+0] = CLIP<int>(buffer[j*2+0] + output_l / 6, -32768, 32767); buffer[j*2+1] = CLIP<int>(buffer[j*2+1] + output_r / 6, -32768, 32767); } } void CMSEmulator::portWriteIntern(int chip, int offset, int data) { SAA1099 *saa = &_saa1099[chip]; int reg = saa->selected_reg; int ch; switch (reg) { /* channel i amplitude */ case 0x00: case 0x01: case 0x02: case 0x03: case 0x04: case 0x05: ch = reg & 7; saa->channels[ch].amplitude[LEFT] = amplitude_lookup[data & 0x0f]; saa->channels[ch].amplitude[RIGHT] = amplitude_lookup[(data >> 4) & 0x0f]; break; /* channel i frequency */ case 0x08: case 0x09: case 0x0a: case 0x0b: case 0x0c: case 0x0d: ch = reg & 7; saa->channels[ch].frequency = data & 0xff; break; /* channel i octave */ case 0x10: case 0x11: case 0x12: ch = (reg - 0x10) << 1; saa->channels[ch + 0].octave = data & 0x07; saa->channels[ch + 1].octave = (data >> 4) & 0x07; break; /* channel i frequency enable */ case 0x14: saa->channels[0].freq_enable = data & 0x01; saa->channels[1].freq_enable = data & 0x02; saa->channels[2].freq_enable = data & 0x04; saa->channels[3].freq_enable = data & 0x08; saa->channels[4].freq_enable = data & 0x10; saa->channels[5].freq_enable = data & 0x20; break; /* channel i noise enable */ case 0x15: saa->channels[0].noise_enable = data & 0x01; saa->channels[1].noise_enable = data & 0x02; saa->channels[2].noise_enable = data & 0x04; saa->channels[3].noise_enable = data & 0x08; saa->channels[4].noise_enable = data & 0x10; saa->channels[5].noise_enable = data & 0x20; break; /* noise generators parameters */ case 0x16: saa->noise_params[0] = data & 0x03; saa->noise_params[1] = (data >> 4) & 0x03; break; /* envelope generators parameters */ case 0x18: case 0x19: ch = reg - 0x18; saa->env_reverse_right[ch] = data & 0x01; saa->env_mode[ch] = (data >> 1) & 0x07; saa->env_bits[ch] = data & 0x10; saa->env_clock[ch] = data & 0x20; saa->env_enable[ch] = data & 0x80; /* reset the envelope */ saa->env_step[ch] = 0; break; /* channels enable & reset generators */ case 0x1c: saa->all_ch_enable = data & 0x01; saa->sync_state = data & 0x02; if (data & 0x02) { int i; /* Synch & Reset generators */ for (i = 0; i < 6; i++) { saa->channels[i].level = 0; saa->channels[i].counter = 0.0; } } break; default: // The CMS allows all registers to be written, so we just output some debug // message here debug(5, "CMS Unknown write to reg %x with %x",reg, data); } } class CMSMusicPlugin : public NullMusicPlugin { public: const char *getName() const { return _s("Creative Music System Emulator"); } const char *getId() const { return "cms"; } MusicDevices getDevices() const; }; MusicDevices CMSMusicPlugin::getDevices() const { MusicDevices devices; devices.push_back(MusicDevice(this, "", MT_CMS)); return devices; } //#if PLUGIN_ENABLED_DYNAMIC(CMS) //REGISTER_PLUGIN_DYNAMIC(CMS, PLUGIN_TYPE_MUSIC, CMSMusicPlugin); //#else REGISTER_PLUGIN_STATIC(CMS, PLUGIN_TYPE_MUSIC, CMSMusicPlugin); //#endif