Files
scummvm-cursorfix/engines/ultima/nuvie/sound/decoder/pc_speaker.cpp
2026-02-02 04:50:13 +01:00

151 lines
4.1 KiB
C++

/*
* PCSpeaker.cpp
* Nuvie
*
* Created by Eric Fry on Sun Feb 13 2011.
* Copyright (c) 2011. All rights reserved.
*
* 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 3 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, see <http://www.gnu.org/licenses/>.
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/
#include "ultima/nuvie/core/nuvie_defs.h"
#include "ultima/nuvie/sound/decoder/pc_speaker.h"
#include "audio/mixer.h"
namespace Ultima {
namespace Nuvie {
#define SPKR_VOLUME 5000
//#define SPKR_SHIFT 8
#define SPKR_SPEED (float)((SPKR_VOLUME*2)/0.070f)
#define PIT_TICK_RATE 1193182
void PCSpeaker::SetOn() {
wav_length = 0;
/*
//PCSPEAKER_SetType(3);
dataFile.open("/Users/efry/pcspeaker.wav");
dataFile.writeBuf((const unsigned char*)"RIFF", 4);
dataFile.write4(36 + wav_length * 2); //length of RIFF chunk
dataFile.writeBuf((const unsigned char*)"WAVE", 4);
dataFile.writeBuf((const unsigned char*)"fmt ", 4);
dataFile.write4(16); // length of format chunk
dataFile.write2(1); // PCM encoding
dataFile.write2(1); // mono
dataFile.write4(rate); // sample frequency 16KHz
dataFile.write4(rate * 2); // sample rate
dataFile.write2(2); // BlockAlign
dataFile.write2(16); // Bits per sample
dataFile.writeBuf((const unsigned char*)"data", 4);
dataFile.write4(wav_length * 2); // length of data chunk
*/
time_left = 0.0;
want_vol = -SPKR_VOLUME;
}
void PCSpeaker::SetOff() {
want_vol = 0;
time_left = 0.0;
/*
//PCSPEAKER_SetType(0);
dataFile.seek(4);
dataFile.write4(36 + wav_length * 2); //length of RIFF chunk
dataFile.seek(40);
dataFile.write4(wav_length * 2); // length of data chunk
dataFile.close();
*/
}
void PCSpeaker::SetFrequency(uint16 freq, float offset) {
//PCSPEAKER_SetCounter(PIT_TICK_RATE/freq, PIT_MODE_3_SQUAREWAVE);
if (frequency == freq)
return;
frequency = freq;
osc_length = rate / frequency;
osc_samples = 0;
half_period = ((float)rate / (float)frequency) / 2;
//want_vol = SPKR_VOLUME;
//DEBUG(0, LEVEL_DEBUGGING, "new_freq = %d half_period = %f time_left = %f", freq, half_period, time_left);
//time_left = offset; //half_period;
}
PCSpeaker::PCSpeaker(uint32 mixer_rate) : rate(mixer_rate), cur_vol(0.0f), want_vol(0.0f),
frequency(0), half_period(0.0f), time_left(0.0f), osc_length(0),
osc_samples(0), wav_length(0) {
}
void PCSpeaker::PCSPEAKER_CallBack(sint16 *stream, const uint32 len) {
uint32 i;
for (i = 0; i < len; i++) {
//float new_time_left = time_left - 1;
if (cur_vol != want_vol) {
if (time_left < 1.0f)
cur_vol = cur_vol + ((want_vol * 8.3502) * time_left) / 2;
else
cur_vol = cur_vol + ((want_vol * 8.3502) / 2);
if (cur_vol > SPKR_VOLUME || cur_vol < -SPKR_VOLUME) { //limit the volume to our max speaker range.
cur_vol = want_vol;
}
}
if (time_left <= 1.0f) { //we change wave direction in this time slice.
//change wave edge.
if (want_vol < 0)
want_vol = SPKR_VOLUME;
else
want_vol = -SPKR_VOLUME;
float remainder = (1.0f - time_left);
if (remainder != 0.0f) { //calculate new current volume position
cur_vol = cur_vol + ((want_vol * 8.3502) * remainder) / 2;
if (cur_vol > SPKR_VOLUME || cur_vol < -SPKR_VOLUME) { //limit the volume to our max speaker range.
cur_vol = want_vol;
}
}
time_left = half_period - remainder;
//DEBUG(0, LEVEL_DEBUGGING, "remainder = %f, time_left = %f\n", remainder, time_left);
} else
time_left = time_left - 1.0f;
stream[i] = (sint16)cur_vol;
//dataFile.write2(stream[i]);
//wav_length++;
}
return;
}
} // End of namespace Nuvie
} // End of namespace Ultima