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+/* 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.
+ *
+ */
+
+#ifndef SCUMM_PLAYERS_PLAYER_APPLEII_H
+#define SCUMM_PLAYERS_PLAYER_APPLEII_H
+
+#include "common/mutex.h"
+#include "common/scummsys.h"
+#include "common/memstream.h"
+#include "scumm/music.h"
+#include "audio/audiostream.h"
+#include "audio/mixer.h"
+#include "audio/softsynth/sid.h"
+
+namespace Scumm {
+
+class ScummEngine;
+
+/*
+ * Optimized for use with periodical read/write phases when the buffer
+ * is filled in a write phase and completely read in a read phase.
+ * The growing strategy is optimized for repeated small (e.g. 2 bytes)
+ * single writes resulting in large buffers
+ * (avg.: 4KB, max: 18KB @ 16bit/22.050kHz (MM sound21)).
+ */
+class SampleBuffer {
+public:
+ SampleBuffer() : _data(0) {
+ clear();
+ }
+
+ ~SampleBuffer() {
+ free(_data);
+ }
+
+ void clear() {
+ free(_data);
+ _data = 0;
+ _capacity = 0;
+ _writePos = 0;
+ _readPos = 0;
+ }
+
+ void ensureFree(uint32 needed) {
+ // if data was read completely, reset read/write pos to front
+ if ((_writePos != 0) && (_writePos == _readPos)) {
+ _writePos = 0;
+ _readPos = 0;
+ }
+
+ // check for enough space at end of buffer
+ uint32 freeEndCnt = _capacity - _writePos;
+ if (needed <= freeEndCnt)
+ return;
+
+ uint32 avail = availableSize();
+
+ // check for enough space at beginning and end of buffer
+ if (needed <= _readPos + freeEndCnt) {
+ // move unread data to front of buffer
+ memmove(_data, _data + _readPos, avail);
+ _writePos = avail;
+ _readPos = 0;
+ } else { // needs a grow
+ byte *old_data = _data;
+ uint32 new_len = avail + needed;
+
+ _capacity = new_len + 2048;
+ _data = (byte *)malloc(_capacity);
+
+ if (old_data) {
+ // copy old unread data to front of new buffer
+ memcpy(_data, old_data + _readPos, avail);
+ free(old_data);
+ _writePos = avail;
+ _readPos = 0;
+ }
+ }
+ }
+
+ uint32 availableSize() const {
+ if (_readPos >= _writePos)
+ return 0;
+ return _writePos - _readPos;
+ }
+
+ uint32 write(const void *dataPtr, uint32 dataSize) {
+ ensureFree(dataSize);
+ memcpy(_data + _writePos, dataPtr, dataSize);
+ _writePos += dataSize;
+ return dataSize;
+ }
+
+ uint32 read(byte *dataPtr, uint32 dataSize) {
+ uint32 avail = availableSize();
+ if (avail == 0)
+ return 0;
+ if (dataSize > avail)
+ dataSize = avail;
+ memcpy(dataPtr, _data + _readPos, dataSize);
+ _readPos += dataSize;
+ return dataSize;
+ }
+
+private:
+ uint32 _writePos;
+ uint32 _readPos;
+ uint32 _capacity;
+ byte *_data;
+};
+
+// CPU_CLOCK according to AppleWin
+static const double APPLEII_CPU_CLOCK = 1020484.5; // ~ 1.02 MHz
+
+/*
+ * Converts the 1-bit speaker state values into audio samples.
+ * This is done by aggregation of the speaker states at each
+ * CPU cycle in a sampling period into an audio sample.
+ */
+class SampleConverter {
+private:
+ void addSampleToBuffer(int sample) {
+ int16 value = sample * _volume / _maxVolume;
+ _buffer.write(&value, sizeof(value));
+ }
+
+public:
+ SampleConverter() :
+ _cyclesPerSampleFP(0),
+ _missingCyclesFP(0),
+ _sampleCyclesSumFP(0),
+ _volume(_maxVolume)
+ {}
+
+ ~SampleConverter() {}
+
+ void reset() {
+ _missingCyclesFP = 0;
+ _sampleCyclesSumFP = 0;
+ _buffer.clear();
+ }
+
+ uint32 availableSize() const {
+ return _buffer.availableSize();
+ }
+
+ void setMusicVolume(int vol) {
+ assert(vol >= 0 && vol <= _maxVolume);
+ _volume = vol;
+ }
+
+ void setSampleRate(int rate) {
+ /* ~46 CPU cycles per sample @ 22.05kHz */
+ _cyclesPerSampleFP = int(APPLEII_CPU_CLOCK * (1 << PREC_SHIFT) / rate);
+ reset();
+ }
+
+ void addCycles(byte level, const int cycles) {
+ /* convert to fixed precision floats */
+ int cyclesFP = cycles << PREC_SHIFT;
+
+ // step 1: if cycles are left from the last call, process them first
+ if (_missingCyclesFP > 0) {
+ int n = (_missingCyclesFP < cyclesFP) ? _missingCyclesFP : cyclesFP;
+ if (level)
+ _sampleCyclesSumFP += n;
+ cyclesFP -= n;
+ _missingCyclesFP -= n;
+ if (_missingCyclesFP == 0) {
+ addSampleToBuffer(2*32767 * _sampleCyclesSumFP / _cyclesPerSampleFP - 32767);
+ } else {
+ return;
+ }
+ }
+
+ _sampleCyclesSumFP = 0;
+
+ // step 2: process blocks of cycles fitting into a whole sample
+ while (cyclesFP >= _cyclesPerSampleFP) {
+ addSampleToBuffer(level ? 32767 : -32767);
+ cyclesFP -= _cyclesPerSampleFP;
+ }
+
+ // step 3: remember cycles left for next call
+ if (cyclesFP > 0) {
+ _missingCyclesFP = _cyclesPerSampleFP - cyclesFP;
+ if (level)
+ _sampleCyclesSumFP = cyclesFP;
+ }
+ }
+
+ uint32 readSamples(void *buffer, int numSamples) {
+ return _buffer.read((byte *)buffer, numSamples * 2) / 2;
+ }
+
+private:
+ static const int PREC_SHIFT = 7;
+
+private:
+ int _cyclesPerSampleFP; /* (fixed precision) */
+ int _missingCyclesFP; /* (fixed precision) */
+ int _sampleCyclesSumFP; /* (fixed precision) */
+ int _volume; /* 0 - 256 */
+ static const int _maxVolume = 256;
+ SampleBuffer _buffer;
+};
+
+class Player_AppleII;
+
+class AppleII_SoundFunction {
+public:
+ AppleII_SoundFunction() {}
+ virtual ~AppleII_SoundFunction() {}
+ virtual void init(Player_AppleII *player, const byte *params) = 0;
+ /* returns true if finished */
+ virtual bool update() = 0;
+protected:
+ Player_AppleII *_player;
+};
+
+class Player_AppleII : public Audio::AudioStream, public MusicEngine {
+public:
+ Player_AppleII(ScummEngine *scumm, Audio::Mixer *mixer);
+ virtual ~Player_AppleII();
+
+ virtual void setMusicVolume(int vol) { _sampleConverter.setMusicVolume(vol); }
+ void setSampleRate(int rate) {
+ _sampleRate = rate;
+ _sampleConverter.setSampleRate(rate);
+ }
+ virtual void startSound(int sound);
+ virtual void stopSound(int sound);
+ virtual void stopAllSounds();
+ virtual int getSoundStatus(int sound) const;
+ virtual int getMusicTimer();
+
+ // AudioStream API
+ int readBuffer(int16 *buffer, const int numSamples);
+ bool isStereo() const { return false; }
+ bool endOfData() const { return false; }
+ int getRate() const { return _sampleRate; }
+
+public:
+ void speakerToggle();
+ void generateSamples(int cycles);
+ void wait(int interval, int count);
+
+private:
+ // sound number
+ int _soundNr;
+ // type of sound
+ int _type;
+ // number of loops left
+ int _loop;
+ // global sound param list
+ const byte *_params;
+ // speaker toggle state (0 / 1)
+ byte _speakerState;
+ // sound function
+ AppleII_SoundFunction *_soundFunc;
+ // cycle to sample converter
+ SampleConverter _sampleConverter;
+
+private:
+ ScummEngine *_vm;
+ Audio::Mixer *_mixer;
+ Audio::SoundHandle _soundHandle;
+ int _sampleRate;
+ Common::Mutex _mutex;
+
+private:
+ void resetState();
+ bool updateSound();
+};
+
+} // End of namespace Scumm
+
+#endif