Mercurial > vba-linux
diff src/apu/Blip_Buffer.cpp @ 3:b05d00f19d80
fix some formatting
author | Robert McIntyre <rlm@mit.edu> |
---|---|
date | Sat, 03 Mar 2012 10:33:11 -0600 |
parents | f9f4f1b99eed |
children |
line wrap: on
line diff
1.1 --- a/src/apu/Blip_Buffer.cpp Sat Mar 03 10:31:47 2012 -0600 1.2 +++ b/src/apu/Blip_Buffer.cpp Sat Mar 03 10:33:11 2012 -0600 1.3 @@ -9,207 +9,207 @@ 1.4 #include <math.h> 1.5 1.6 /* Copyright (C) 2003-2007 Shay Green. This module is free software; you 1.7 -can redistribute it and/or modify it under the terms of the GNU Lesser 1.8 -General Public License as published by the Free Software Foundation; either 1.9 -version 2.1 of the License, or (at your option) any later version. This 1.10 -module is distributed in the hope that it will be useful, but WITHOUT ANY 1.11 -WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 1.12 -FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more 1.13 -details. You should have received a copy of the GNU Lesser General Public 1.14 -License along with this module; if not, write to the Free Software Foundation, 1.15 -Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ 1.16 + can redistribute it and/or modify it under the terms of the GNU Lesser 1.17 + General Public License as published by the Free Software Foundation; either 1.18 + version 2.1 of the License, or (at your option) any later version. This 1.19 + module is distributed in the hope that it will be useful, but WITHOUT ANY 1.20 + WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 1.21 + FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more 1.22 + details. You should have received a copy of the GNU Lesser General Public 1.23 + License along with this module; if not, write to the Free Software Foundation, 1.24 + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ 1.25 1.26 // TODO: use scoped for variables in treble_eq() 1.27 1.28 #ifdef BLARGG_ENABLE_OPTIMIZER 1.29 - #include BLARGG_ENABLE_OPTIMIZER 1.30 +#include BLARGG_ENABLE_OPTIMIZER 1.31 #endif 1.32 1.33 int const silent_buf_size = 1; // size used for Silent_Blip_Buffer 1.34 1.35 Blip_Buffer::Blip_Buffer() 1.36 { 1.37 - factor_ = LONG_MAX; 1.38 - buffer_ = 0; 1.39 - buffer_size_ = 0; 1.40 - sample_rate_ = 0; 1.41 - bass_shift_ = 0; 1.42 - clock_rate_ = 0; 1.43 - bass_freq_ = 16; 1.44 - length_ = 0; 1.45 + factor_ = LONG_MAX; 1.46 + buffer_ = 0; 1.47 + buffer_size_ = 0; 1.48 + sample_rate_ = 0; 1.49 + bass_shift_ = 0; 1.50 + clock_rate_ = 0; 1.51 + bass_freq_ = 16; 1.52 + length_ = 0; 1.53 1.54 - // assumptions code makes about implementation-defined features 1.55 - #ifndef NDEBUG 1.56 - // right shift of negative value preserves sign 1.57 - buf_t_ i = -0x7FFFFFFE; 1.58 - assert( (i >> 1) == -0x3FFFFFFF ); 1.59 + // assumptions code makes about implementation-defined features 1.60 +#ifndef NDEBUG 1.61 + // right shift of negative value preserves sign 1.62 + buf_t_ i = -0x7FFFFFFE; 1.63 + assert( (i >> 1) == -0x3FFFFFFF ); 1.64 1.65 - // casting to short truncates to 16 bits and sign-extends 1.66 - i = 0x18000; 1.67 - assert( (short) i == -0x8000 ); 1.68 - #endif 1.69 + // casting to short truncates to 16 bits and sign-extends 1.70 + i = 0x18000; 1.71 + assert( (short) i == -0x8000 ); 1.72 +#endif 1.73 1.74 - clear(); 1.75 + Clear(); 1.76 } 1.77 1.78 Blip_Buffer::~Blip_Buffer() 1.79 { 1.80 - if ( buffer_size_ != silent_buf_size ) 1.81 - free( buffer_ ); 1.82 + if ( buffer_size_ != silent_buf_size ) 1.83 + free( buffer_ ); 1.84 } 1.85 1.86 Silent_Blip_Buffer::Silent_Blip_Buffer() 1.87 { 1.88 - factor_ = 0; 1.89 - buffer_ = buf; 1.90 - buffer_size_ = silent_buf_size; 1.91 - clear(); 1.92 + factor_ = 0; 1.93 + buffer_ = buf; 1.94 + buffer_size_ = silent_buf_size; 1.95 + clear(); 1.96 } 1.97 1.98 void Blip_Buffer::clear( int entire_buffer ) 1.99 { 1.100 - offset_ = 0; 1.101 - reader_accum_ = 0; 1.102 - modified_ = 0; 1.103 - if ( buffer_ ) 1.104 - { 1.105 - long count = (entire_buffer ? buffer_size_ : samples_avail()); 1.106 - memset( buffer_, 0, (count + blip_buffer_extra_) * sizeof (buf_t_) ); 1.107 - } 1.108 + offset_ = 0; 1.109 + reader_accum_ = 0; 1.110 + modified_ = 0; 1.111 + if ( buffer_ ) 1.112 + { 1.113 + long count = (entire_buffer ? buffer_size_ : samples_avail()); 1.114 + memset( buffer_, 0, (count + blip_buffer_extra_) * sizeof (buf_t_) ); 1.115 + } 1.116 } 1.117 1.118 Blip_Buffer::blargg_err_t Blip_Buffer::set_sample_rate( long new_rate, int msec ) 1.119 { 1.120 - if ( buffer_size_ == silent_buf_size ) 1.121 - { 1.122 - assert( 0 ); 1.123 - return "Internal (tried to resize Silent_Blip_Buffer)"; 1.124 - } 1.125 + if ( buffer_size_ == silent_buf_size ) 1.126 + { 1.127 + assert( 0 ); 1.128 + return "Internal (tried to resize Silent_Blip_Buffer)"; 1.129 + } 1.130 1.131 - // start with maximum length that resampled time can represent 1.132 - long new_size = (ULONG_MAX >> BLIP_BUFFER_ACCURACY) - blip_buffer_extra_ - 64; 1.133 - if ( msec != blip_max_length ) 1.134 - { 1.135 - long s = (new_rate * (msec + 1) + 999) / 1000; 1.136 - if ( s < new_size ) 1.137 - new_size = s; 1.138 - else 1.139 - assert( 0 ); // fails if requested buffer length exceeds limit 1.140 - } 1.141 + // start with maximum length that resampled time can represent 1.142 + long new_size = (ULONG_MAX >> BLIP_BUFFER_ACCURACY) - blip_buffer_extra_ - 64; 1.143 + if ( msec != blip_max_length ) 1.144 + { 1.145 + long s = (new_rate * (msec + 1) + 999) / 1000; 1.146 + if ( s < new_size ) 1.147 + new_size = s; 1.148 + else 1.149 + assert( 0 ); // fails if requested buffer length exceeds limit 1.150 + } 1.151 1.152 - if ( buffer_size_ != new_size ) 1.153 - { 1.154 - void* p = realloc( buffer_, (new_size + blip_buffer_extra_) * sizeof *buffer_ ); 1.155 - if ( !p ) 1.156 - return "Out of memory"; 1.157 - buffer_ = (buf_t_*) p; 1.158 - } 1.159 + if ( buffer_size_ != new_size ) 1.160 + { 1.161 + void* p = realloc( buffer_, (new_size + blip_buffer_extra_) * sizeof *buffer_ ); 1.162 + if ( !p ) 1.163 + return "Out of memory"; 1.164 + buffer_ = (buf_t_*) p; 1.165 + } 1.166 1.167 - buffer_size_ = new_size; 1.168 - assert( buffer_size_ != silent_buf_size ); // size should never happen to match this 1.169 + buffer_size_ = new_size; 1.170 + assert( buffer_size_ != silent_buf_size ); // size should never happen to match this 1.171 1.172 - // update things based on the sample rate 1.173 - sample_rate_ = new_rate; 1.174 - length_ = new_size * 1000 / new_rate - 1; 1.175 - if ( msec ) 1.176 - assert( length_ == msec ); // ensure length is same as that passed in 1.177 + // update things based on the sample rate 1.178 + sample_rate_ = new_rate; 1.179 + length_ = new_size * 1000 / new_rate - 1; 1.180 + if ( msec ) 1.181 + assert( length_ == msec ); // ensure length is same as that passed in 1.182 1.183 - // update these since they depend on sample rate 1.184 - if ( clock_rate_ ) 1.185 - clock_rate( clock_rate_ ); 1.186 - bass_freq( bass_freq_ ); 1.187 + // update these since they depend on sample rate 1.188 + if ( clock_rate_ ) 1.189 + clock_rate( clock_rate_ ); 1.190 + bass_freq( bass_freq_ ); 1.191 1.192 - clear(); 1.193 + clear(); 1.194 1.195 - return 0; // success 1.196 + return 0; // success 1.197 } 1.198 1.199 blip_resampled_time_t Blip_Buffer::clock_rate_factor( long rate ) const 1.200 { 1.201 - double ratio = (double) sample_rate_ / rate; 1.202 - blip_long factor = (blip_long) floor( ratio * (1L << BLIP_BUFFER_ACCURACY) + 0.5 ); 1.203 - assert( factor > 0 || !sample_rate_ ); // fails if clock/output ratio is too large 1.204 - return (blip_resampled_time_t) factor; 1.205 + double ratio = (double) sample_rate_ / rate; 1.206 + blip_long factor = (blip_long) floor( ratio * (1L << BLIP_BUFFER_ACCURACY) + 0.5 ); 1.207 + assert( factor > 0 || !sample_rate_ ); // fails if clock/output ratio is too large 1.208 + return (blip_resampled_time_t) factor; 1.209 } 1.210 1.211 void Blip_Buffer::bass_freq( int freq ) 1.212 { 1.213 - bass_freq_ = freq; 1.214 - int shift = 31; 1.215 - if ( freq > 0 ) 1.216 - { 1.217 - shift = 13; 1.218 - long f = (freq << 16) / sample_rate_; 1.219 - while ( (f >>= 1) && --shift ) { } 1.220 - } 1.221 - bass_shift_ = shift; 1.222 + bass_freq_ = freq; 1.223 + int shift = 31; 1.224 + if ( freq > 0 ) 1.225 + { 1.226 + shift = 13; 1.227 + long f = (freq << 16) / sample_rate_; 1.228 + while ( (f >>= 1) && --shift ) { } 1.229 + } 1.230 + bass_shift_ = shift; 1.231 } 1.232 1.233 void Blip_Buffer::end_frame( blip_time_t t ) 1.234 { 1.235 - offset_ += t * factor_; 1.236 - assert( samples_avail() <= (long) buffer_size_ ); // fails if time is past end of buffer 1.237 + offset_ += t * factor_; 1.238 + assert( samples_avail() <= (long) buffer_size_ ); // fails if time is past end of buffer 1.239 } 1.240 1.241 long Blip_Buffer::count_samples( blip_time_t t ) const 1.242 { 1.243 - blip_resampled_time_t last_sample = resampled_time( t ) >> BLIP_BUFFER_ACCURACY; 1.244 - blip_resampled_time_t first_sample = offset_ >> BLIP_BUFFER_ACCURACY; 1.245 - return long (last_sample - first_sample); 1.246 + blip_resampled_time_t last_sample = resampled_time( t ) >> BLIP_BUFFER_ACCURACY; 1.247 + blip_resampled_time_t first_sample = offset_ >> BLIP_BUFFER_ACCURACY; 1.248 + return long (last_sample - first_sample); 1.249 } 1.250 1.251 blip_time_t Blip_Buffer::count_clocks( long count ) const 1.252 { 1.253 - if ( !factor_ ) 1.254 - { 1.255 - assert( 0 ); // sample rate and clock rates must be set first 1.256 - return 0; 1.257 - } 1.258 + if ( !factor_ ) 1.259 + { 1.260 + assert( 0 ); // sample rate and clock rates must be set first 1.261 + return 0; 1.262 + } 1.263 1.264 - if ( count > buffer_size_ ) 1.265 - count = buffer_size_; 1.266 - blip_resampled_time_t time = (blip_resampled_time_t) count << BLIP_BUFFER_ACCURACY; 1.267 - return (blip_time_t) ((time - offset_ + factor_ - 1) / factor_); 1.268 + if ( count > buffer_size_ ) 1.269 + count = buffer_size_; 1.270 + blip_resampled_time_t time = (blip_resampled_time_t) count << BLIP_BUFFER_ACCURACY; 1.271 + return (blip_time_t) ((time - offset_ + factor_ - 1) / factor_); 1.272 } 1.273 1.274 void Blip_Buffer::remove_samples( long count ) 1.275 { 1.276 - if ( count ) 1.277 - { 1.278 - remove_silence( count ); 1.279 + if ( count ) 1.280 + { 1.281 + remove_silence( count ); 1.282 1.283 - // copy remaining samples to beginning and clear old samples 1.284 - long remain = samples_avail() + blip_buffer_extra_; 1.285 - memmove( buffer_, buffer_ + count, remain * sizeof *buffer_ ); 1.286 - memset( buffer_ + remain, 0, count * sizeof *buffer_ ); 1.287 - } 1.288 + // copy remaining samples to beginning and clear old samples 1.289 + long remain = samples_avail() + blip_buffer_extra_; 1.290 + memmove( buffer_, buffer_ + count, remain * sizeof *buffer_ ); 1.291 + memset( buffer_ + remain, 0, count * sizeof *buffer_ ); 1.292 + } 1.293 } 1.294 1.295 // Blip_Synth_ 1.296 1.297 Blip_Synth_Fast_::Blip_Synth_Fast_() 1.298 { 1.299 - buf = 0; 1.300 - last_amp = 0; 1.301 - delta_factor = 0; 1.302 + buf = 0; 1.303 + last_amp = 0; 1.304 + delta_factor = 0; 1.305 } 1.306 1.307 void Blip_Synth_Fast_::volume_unit( double new_unit ) 1.308 { 1.309 - delta_factor = int (new_unit * (1L << blip_sample_bits) + 0.5); 1.310 + delta_factor = int (new_unit * (1L << blip_sample_bits) + 0.5); 1.311 } 1.312 1.313 #if !BLIP_BUFFER_FAST 1.314 1.315 Blip_Synth_::Blip_Synth_( short* p, int w ) : 1.316 - impulses( p ), 1.317 - width( w ) 1.318 + impulses( p ), 1.319 + width( w ) 1.320 { 1.321 - volume_unit_ = 0.0; 1.322 - kernel_unit = 0; 1.323 - buf = 0; 1.324 - last_amp = 0; 1.325 - delta_factor = 0; 1.326 + volume_unit_ = 0.0; 1.327 + kernel_unit = 0; 1.328 + buf = 0; 1.329 + last_amp = 0; 1.330 + delta_factor = 0; 1.331 } 1.332 1.333 #undef PI 1.334 @@ -217,249 +217,249 @@ 1.335 1.336 static void gen_sinc( float* out, int count, double oversample, double treble, double cutoff ) 1.337 { 1.338 - if ( cutoff >= 0.999 ) 1.339 - cutoff = 0.999; 1.340 + if ( cutoff >= 0.999 ) 1.341 + cutoff = 0.999; 1.342 1.343 - if ( treble < -300.0 ) 1.344 - treble = -300.0; 1.345 - if ( treble > 5.0 ) 1.346 - treble = 5.0; 1.347 + if ( treble < -300.0 ) 1.348 + treble = -300.0; 1.349 + if ( treble > 5.0 ) 1.350 + treble = 5.0; 1.351 1.352 - double const maxh = 4096.0; 1.353 - double const rolloff = pow( 10.0, 1.0 / (maxh * 20.0) * treble / (1.0 - cutoff) ); 1.354 - double const pow_a_n = pow( rolloff, maxh - maxh * cutoff ); 1.355 - double const to_angle = PI / 2 / maxh / oversample; 1.356 - for ( int i = 0; i < count; i++ ) 1.357 - { 1.358 - double angle = ((i - count) * 2 + 1) * to_angle; 1.359 - double c = rolloff * cos( (maxh - 1.0) * angle ) - cos( maxh * angle ); 1.360 - double cos_nc_angle = cos( maxh * cutoff * angle ); 1.361 - double cos_nc1_angle = cos( (maxh * cutoff - 1.0) * angle ); 1.362 - double cos_angle = cos( angle ); 1.363 + double const maxh = 4096.0; 1.364 + double const rolloff = pow( 10.0, 1.0 / (maxh * 20.0) * treble / (1.0 - cutoff) ); 1.365 + double const pow_a_n = pow( rolloff, maxh - maxh * cutoff ); 1.366 + double const to_angle = PI / 2 / maxh / oversample; 1.367 + for ( int i = 0; i < count; i++ ) 1.368 + { 1.369 + double angle = ((i - count) * 2 + 1) * to_angle; 1.370 + double c = rolloff * cos( (maxh - 1.0) * angle ) - cos( maxh * angle ); 1.371 + double cos_nc_angle = cos( maxh * cutoff * angle ); 1.372 + double cos_nc1_angle = cos( (maxh * cutoff - 1.0) * angle ); 1.373 + double cos_angle = cos( angle ); 1.374 1.375 - c = c * pow_a_n - rolloff * cos_nc1_angle + cos_nc_angle; 1.376 - double d = 1.0 + rolloff * (rolloff - cos_angle - cos_angle); 1.377 - double b = 2.0 - cos_angle - cos_angle; 1.378 - double a = 1.0 - cos_angle - cos_nc_angle + cos_nc1_angle; 1.379 + c = c * pow_a_n - rolloff * cos_nc1_angle + cos_nc_angle; 1.380 + double d = 1.0 + rolloff * (rolloff - cos_angle - cos_angle); 1.381 + double b = 2.0 - cos_angle - cos_angle; 1.382 + double a = 1.0 - cos_angle - cos_nc_angle + cos_nc1_angle; 1.383 1.384 - out [i] = (float) ((a * d + c * b) / (b * d)); // a / b + c / d 1.385 - } 1.386 + out [i] = (float) ((a * d + c * b) / (b * d)); // a / b + c / d 1.387 + } 1.388 } 1.389 1.390 void blip_eq_t::generate( float* out, int count ) const 1.391 { 1.392 - // lower cutoff freq for narrow kernels with their wider transition band 1.393 - // (8 points->1.49, 16 points->1.15) 1.394 - double oversample = blip_res * 2.25 / count + 0.85; 1.395 - double half_rate = sample_rate * 0.5; 1.396 - if ( cutoff_freq ) 1.397 - oversample = half_rate / cutoff_freq; 1.398 - double cutoff = rolloff_freq * oversample / half_rate; 1.399 + // lower cutoff freq for narrow kernels with their wider transition band 1.400 + // (8 points->1.49, 16 points->1.15) 1.401 + double oversample = blip_res * 2.25 / count + 0.85; 1.402 + double half_rate = sample_rate * 0.5; 1.403 + if ( cutoff_freq ) 1.404 + oversample = half_rate / cutoff_freq; 1.405 + double cutoff = rolloff_freq * oversample / half_rate; 1.406 1.407 - gen_sinc( out, count, blip_res * oversample, treble, cutoff ); 1.408 + gen_sinc( out, count, blip_res * oversample, treble, cutoff ); 1.409 1.410 - // apply (half of) hamming window 1.411 - double to_fraction = PI / (count - 1); 1.412 - for ( int i = count; i--; ) 1.413 - out [i] *= 0.54f - 0.46f * (float) cos( i * to_fraction ); 1.414 + // apply (half of) hamming window 1.415 + double to_fraction = PI / (count - 1); 1.416 + for ( int i = count; i--; ) 1.417 + out [i] *= 0.54f - 0.46f * (float) cos( i * to_fraction ); 1.418 } 1.419 1.420 void Blip_Synth_::adjust_impulse() 1.421 { 1.422 - // sum pairs for each phase and add error correction to end of first half 1.423 - int const size = impulses_size(); 1.424 - for ( int p = blip_res; p-- >= blip_res / 2; ) 1.425 + // sum pairs for each phase and add error correction to end of first half 1.426 + int const size = impulses_size(); 1.427 + for ( int p = blip_res; p-- >= blip_res / 2; ) 1.428 + { 1.429 + int p2 = blip_res - 2 - p; 1.430 + long error = kernel_unit; 1.431 + for ( int i = 1; i < size; i += blip_res ) 1.432 { 1.433 - int p2 = blip_res - 2 - p; 1.434 - long error = kernel_unit; 1.435 - for ( int i = 1; i < size; i += blip_res ) 1.436 - { 1.437 - error -= impulses [i + p ]; 1.438 - error -= impulses [i + p2]; 1.439 - } 1.440 - if ( p == p2 ) 1.441 - error /= 2; // phase = 0.5 impulse uses same half for both sides 1.442 - impulses [size - blip_res + p] += (short) error; 1.443 - //printf( "error: %ld\n", error ); 1.444 + error -= impulses [i + p ]; 1.445 + error -= impulses [i + p2]; 1.446 } 1.447 + if ( p == p2 ) 1.448 + error /= 2; // phase = 0.5 impulse uses same half for both sides 1.449 + impulses [size - blip_res + p] += (short) error; 1.450 + //printf( "error: %ld\n", error ); 1.451 + } 1.452 1.453 - //for ( int i = blip_res; i--; printf( "\n" ) ) 1.454 - // for ( int j = 0; j < width / 2; j++ ) 1.455 - // printf( "%5ld,", impulses [j * blip_res + i + 1] ); 1.456 + //for ( int i = blip_res; i--; printf( "\n" ) ) 1.457 + // for ( int j = 0; j < width / 2; j++ ) 1.458 + // printf( "%5ld,", impulses [j * blip_res + i + 1] ); 1.459 } 1.460 1.461 void Blip_Synth_::treble_eq( blip_eq_t const& eq ) 1.462 { 1.463 - float fimpulse [blip_res / 2 * (blip_widest_impulse_ - 1) + blip_res * 2]; 1.464 + float fimpulse [blip_res / 2 * (blip_widest_impulse_ - 1) + blip_res * 2]; 1.465 1.466 - int const half_size = blip_res / 2 * (width - 1); 1.467 - eq.generate( &fimpulse [blip_res], half_size ); 1.468 + int const half_size = blip_res / 2 * (width - 1); 1.469 + eq.generate( &fimpulse [blip_res], half_size ); 1.470 1.471 - int i; 1.472 + int i; 1.473 1.474 - // need mirror slightly past center for calculation 1.475 - for ( i = blip_res; i--; ) 1.476 - fimpulse [blip_res + half_size + i] = fimpulse [blip_res + half_size - 1 - i]; 1.477 + // need mirror slightly past center for calculation 1.478 + for ( i = blip_res; i--; ) 1.479 + fimpulse [blip_res + half_size + i] = fimpulse [blip_res + half_size - 1 - i]; 1.480 1.481 - // starts at 0 1.482 - for ( i = 0; i < blip_res; i++ ) 1.483 - fimpulse [i] = 0.0f; 1.484 + // starts at 0 1.485 + for ( i = 0; i < blip_res; i++ ) 1.486 + fimpulse [i] = 0.0f; 1.487 1.488 - // find rescale factor 1.489 - double total = 0.0; 1.490 - for ( i = 0; i < half_size; i++ ) 1.491 - total += fimpulse [blip_res + i]; 1.492 + // find rescale factor 1.493 + double total = 0.0; 1.494 + for ( i = 0; i < half_size; i++ ) 1.495 + total += fimpulse [blip_res + i]; 1.496 1.497 - //double const base_unit = 44800.0 - 128 * 18; // allows treble up to +0 dB 1.498 - //double const base_unit = 37888.0; // allows treble to +5 dB 1.499 - double const base_unit = 32768.0; // necessary for blip_unscaled to work 1.500 - double rescale = base_unit / 2 / total; 1.501 - kernel_unit = (long) base_unit; 1.502 + //double const base_unit = 44800.0 - 128 * 18; // allows treble up to +0 dB 1.503 + //double const base_unit = 37888.0; // allows treble to +5 dB 1.504 + double const base_unit = 32768.0; // necessary for blip_unscaled to work 1.505 + double rescale = base_unit / 2 / total; 1.506 + kernel_unit = (long) base_unit; 1.507 1.508 - // integrate, first difference, rescale, convert to int 1.509 - double sum = 0.0; 1.510 - double next = 0.0; 1.511 - int const size = this->impulses_size(); 1.512 - for ( i = 0; i < size; i++ ) 1.513 - { 1.514 - impulses [i] = (short) (int) floor( (next - sum) * rescale + 0.5 ); 1.515 - sum += fimpulse [i]; 1.516 - next += fimpulse [i + blip_res]; 1.517 - } 1.518 - adjust_impulse(); 1.519 + // integrate, first difference, rescale, convert to int 1.520 + double sum = 0.0; 1.521 + double next = 0.0; 1.522 + int const size = this->impulses_size(); 1.523 + for ( i = 0; i < size; i++ ) 1.524 + { 1.525 + impulses [i] = (short) (int) floor( (next - sum) * rescale + 0.5 ); 1.526 + sum += fimpulse [i]; 1.527 + next += fimpulse [i + blip_res]; 1.528 + } 1.529 + adjust_impulse(); 1.530 1.531 - // volume might require rescaling 1.532 - double vol = volume_unit_; 1.533 - if ( vol ) 1.534 - { 1.535 - volume_unit_ = 0.0; 1.536 - volume_unit( vol ); 1.537 - } 1.538 + // volume might require rescaling 1.539 + double vol = volume_unit_; 1.540 + if ( vol ) 1.541 + { 1.542 + volume_unit_ = 0.0; 1.543 + volume_unit( vol ); 1.544 + } 1.545 } 1.546 1.547 void Blip_Synth_::volume_unit( double new_unit ) 1.548 { 1.549 - if ( new_unit != volume_unit_ ) 1.550 + if ( new_unit != volume_unit_ ) 1.551 + { 1.552 + // use default eq if it hasn't been set yet 1.553 + if ( !kernel_unit ) 1.554 + treble_eq( -8.0 ); 1.555 + 1.556 + volume_unit_ = new_unit; 1.557 + double factor = new_unit * (1L << blip_sample_bits) / kernel_unit; 1.558 + 1.559 + if ( factor > 0.0 ) 1.560 { 1.561 - // use default eq if it hasn't been set yet 1.562 - if ( !kernel_unit ) 1.563 - treble_eq( -8.0 ); 1.564 + int shift = 0; 1.565 1.566 - volume_unit_ = new_unit; 1.567 - double factor = new_unit * (1L << blip_sample_bits) / kernel_unit; 1.568 + // if unit is really small, might need to attenuate kernel 1.569 + while ( factor < 2.0 ) 1.570 + { 1.571 + shift++; 1.572 + factor *= 2.0; 1.573 + } 1.574 1.575 - if ( factor > 0.0 ) 1.576 - { 1.577 - int shift = 0; 1.578 + if ( shift ) 1.579 + { 1.580 + kernel_unit >>= shift; 1.581 + assert( kernel_unit > 0 ); // fails if volume unit is too low 1.582 1.583 - // if unit is really small, might need to attenuate kernel 1.584 - while ( factor < 2.0 ) 1.585 - { 1.586 - shift++; 1.587 - factor *= 2.0; 1.588 - } 1.589 - 1.590 - if ( shift ) 1.591 - { 1.592 - kernel_unit >>= shift; 1.593 - assert( kernel_unit > 0 ); // fails if volume unit is too low 1.594 - 1.595 - // keep values positive to avoid round-towards-zero of sign-preserving 1.596 - // right shift for negative values 1.597 - long offset = 0x8000 + (1 << (shift - 1)); 1.598 - long offset2 = 0x8000 >> shift; 1.599 - for ( int i = impulses_size(); i--; ) 1.600 - impulses [i] = (short) (int) (((impulses [i] + offset) >> shift) - offset2); 1.601 - adjust_impulse(); 1.602 - } 1.603 - } 1.604 - delta_factor = (int) floor( factor + 0.5 ); 1.605 - //printf( "delta_factor: %d, kernel_unit: %d\n", delta_factor, kernel_unit ); 1.606 + // keep values positive to avoid round-towards-zero of sign-preserving 1.607 + // right shift for negative values 1.608 + long offset = 0x8000 + (1 << (shift - 1)); 1.609 + long offset2 = 0x8000 >> shift; 1.610 + for ( int i = impulses_size(); i--; ) 1.611 + impulses [i] = (short) (int) (((impulses [i] + offset) >> shift) - offset2); 1.612 + adjust_impulse(); 1.613 + } 1.614 } 1.615 + delta_factor = (int) floor( factor + 0.5 ); 1.616 + //printf( "delta_factor: %d, kernel_unit: %d\n", delta_factor, kernel_unit ); 1.617 + } 1.618 } 1.619 #endif 1.620 1.621 long Blip_Buffer::read_samples( blip_sample_t* out_, long max_samples, int stereo ) 1.622 { 1.623 - long count = samples_avail(); 1.624 - if ( count > max_samples ) 1.625 - count = max_samples; 1.626 + long count = samples_avail(); 1.627 + if ( count > max_samples ) 1.628 + count = max_samples; 1.629 1.630 - if ( count ) 1.631 + if ( count ) 1.632 + { 1.633 + int const bass = BLIP_READER_BASS( *this ); 1.634 + BLIP_READER_BEGIN( reader, *this ); 1.635 + BLIP_READER_ADJ_( reader, count ); 1.636 + blip_sample_t* BLIP_RESTRICT out = out_ + count; 1.637 + blip_long offset = (blip_long) -count; 1.638 + 1.639 + if ( !stereo ) 1.640 { 1.641 - int const bass = BLIP_READER_BASS( *this ); 1.642 - BLIP_READER_BEGIN( reader, *this ); 1.643 - BLIP_READER_ADJ_( reader, count ); 1.644 - blip_sample_t* BLIP_RESTRICT out = out_ + count; 1.645 - blip_long offset = (blip_long) -count; 1.646 + do 1.647 + { 1.648 + blip_long s = BLIP_READER_READ( reader ); 1.649 + BLIP_READER_NEXT_IDX_( reader, bass, offset ); 1.650 + BLIP_CLAMP( s, s ); 1.651 + out [offset] = (blip_sample_t) s; 1.652 + } 1.653 + while ( ++offset ); 1.654 + } 1.655 + else 1.656 + { 1.657 + do 1.658 + { 1.659 + blip_long s = BLIP_READER_READ( reader ); 1.660 + BLIP_READER_NEXT_IDX_( reader, bass, offset ); 1.661 + BLIP_CLAMP( s, s ); 1.662 + out [offset * 2] = (blip_sample_t) s; 1.663 + } 1.664 + while ( ++offset ); 1.665 + } 1.666 1.667 - if ( !stereo ) 1.668 - { 1.669 - do 1.670 - { 1.671 - blip_long s = BLIP_READER_READ( reader ); 1.672 - BLIP_READER_NEXT_IDX_( reader, bass, offset ); 1.673 - BLIP_CLAMP( s, s ); 1.674 - out [offset] = (blip_sample_t) s; 1.675 - } 1.676 - while ( ++offset ); 1.677 - } 1.678 - else 1.679 - { 1.680 - do 1.681 - { 1.682 - blip_long s = BLIP_READER_READ( reader ); 1.683 - BLIP_READER_NEXT_IDX_( reader, bass, offset ); 1.684 - BLIP_CLAMP( s, s ); 1.685 - out [offset * 2] = (blip_sample_t) s; 1.686 - } 1.687 - while ( ++offset ); 1.688 - } 1.689 + BLIP_READER_END( reader, *this ); 1.690 1.691 - BLIP_READER_END( reader, *this ); 1.692 - 1.693 - remove_samples( count ); 1.694 - } 1.695 - return count; 1.696 + remove_samples( count ); 1.697 + } 1.698 + return count; 1.699 } 1.700 1.701 void Blip_Buffer::mix_samples( blip_sample_t const* in, long count ) 1.702 { 1.703 - if ( buffer_size_ == silent_buf_size ) 1.704 - { 1.705 - assert( 0 ); 1.706 - return; 1.707 - } 1.708 + if ( buffer_size_ == silent_buf_size ) 1.709 + { 1.710 + assert( 0 ); 1.711 + return; 1.712 + } 1.713 1.714 - buf_t_* out = buffer_ + (offset_ >> BLIP_BUFFER_ACCURACY) + blip_widest_impulse_ / 2; 1.715 + buf_t_* out = buffer_ + (offset_ >> BLIP_BUFFER_ACCURACY) + blip_widest_impulse_ / 2; 1.716 1.717 - int const sample_shift = blip_sample_bits - 16; 1.718 - int prev = 0; 1.719 - while ( count-- ) 1.720 - { 1.721 - blip_long s = (blip_long) *in++ << sample_shift; 1.722 - *out += s - prev; 1.723 - prev = s; 1.724 - ++out; 1.725 - } 1.726 - *out -= prev; 1.727 + int const sample_shift = blip_sample_bits - 16; 1.728 + int prev = 0; 1.729 + while ( count-- ) 1.730 + { 1.731 + blip_long s = (blip_long) *in++ << sample_shift; 1.732 + *out += s - prev; 1.733 + prev = s; 1.734 + ++out; 1.735 + } 1.736 + *out -= prev; 1.737 } 1.738 1.739 blip_ulong const subsample_mask = (1L << BLIP_BUFFER_ACCURACY) - 1; 1.740 1.741 void Blip_Buffer::save_state( blip_buffer_state_t* out ) 1.742 { 1.743 - assert( samples_avail() == 0 ); 1.744 - out->offset_ = offset_; 1.745 - out->reader_accum_ = reader_accum_; 1.746 - memcpy( out->buf, &buffer_ [offset_ >> BLIP_BUFFER_ACCURACY], sizeof out->buf ); 1.747 + assert( samples_avail() == 0 ); 1.748 + out->offset_ = offset_; 1.749 + out->reader_accum_ = reader_accum_; 1.750 + memcpy( out->buf, &buffer_ [offset_ >> BLIP_BUFFER_ACCURACY], sizeof out->buf ); 1.751 } 1.752 1.753 void Blip_Buffer::load_state( blip_buffer_state_t const& in ) 1.754 { 1.755 - clear( false ); 1.756 + clear( false ); 1.757 1.758 - offset_ = in.offset_; 1.759 - reader_accum_ = in.reader_accum_; 1.760 - memcpy( buffer_, in.buf, sizeof in.buf ); 1.761 + offset_ = in.offset_; 1.762 + reader_accum_ = in.reader_accum_; 1.763 + memcpy( buffer_, in.buf, sizeof in.buf ); 1.764 }