seiichi horie
Synthesizer based on the Unzen / Nucleo F746ZG
Dependencies: amakusa mbed-dsp mbed shimabara ukifune unzen_nucleo_f746
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skeleton_unzen_nucleo_f746
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seiichi horie
雲仙フレームワークのテストとして作っているプロジェクトです。中身はどんどん変っていきます。 説明はDSP空挺団の「シンセサイザー」カテゴリーを参照してください。初回は「ドッグフードを食べる」です。
Diff: eg.cpp
- Revision:
- 26:e99f71165e19
- Child:
- 27:fcb1f1da2ad7
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/eg.cpp Fri Feb 10 21:31:17 2017 +0000
@@ -0,0 +1,69 @@
+#include "signal_processing.h"
+
+EG::EG ( int32_t block_size )
+{
+ this->block_size = block_size;
+
+ this->state = release;
+ this->set_sustain( 0.0f );
+ this->current_level = 0.0f;
+ this->set_attack( 0.999 );
+ this->set_decay( 0.999 );
+ this->set_release( 0.999 );
+
+}
+
+void EG::run( float32_t *pEnvelope )
+{
+ if ( this->state == release )
+ for ( int i= 0; i< this->block_size; i++ )
+ pEnvelope[i] = this->current_level =
+ this->current_level * this->release_time_constant;
+ else if ( this->state == decay )
+ for ( int i= 0; i< this->block_size; i++ )
+ pEnvelope[i] = this->current_level =
+ ( this->current_level - this->sustain_level ) * this->decay_time_constant
+ + this->sustain_level;
+ else // attack
+ {
+ for ( int i= 0; i< this->block_size; i++ )
+ pEnvelope[i] = this->current_level =
+ 1.5f -
+ ( 1.5f - this->current_level ) * this->attack_time_constant;
+ if ( this->current_level >= 1.0f )
+ this->state = decay;
+ }
+
+}
+
+void EG::on(void)
+{
+ this->state = attack;
+}
+
+void EG::off(void)
+{
+ this->state = release;
+}
+
+void EG::set_sustain( float32_t sustain )
+{
+ this->sustain_level = sustain;
+}
+
+void EG::set_attack( float32_t attack )
+{
+ this->attack_time_constant = 1.0f - attack * 0.01f;
+}
+
+void EG::set_decay( float32_t decay )
+{
+ this->decay_time_constant = 1.0f - decay * 0.01f;
+}
+
+void EG::set_release( float32_t release )
+{
+ this->release_time_constant = 1.0f - release * 0.01f;
+}
+
+