Clemens Valens / SoundEngine

This is a part of the Kinetiszer project.

Dependencies:   inc

Dependents:   kinetisizer

envelope.c@1:8ae4ab73ca6a, 2014-10-28 (annotated)

Committer:
Clemo
Date:
Tue Oct 28 20:09:12 2014 +0000
Revision:
1:8ae4ab73ca6a
Parent:
0:cb80470434eb 
First publication (untested)

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Clemo 0:cb80470434eb 1 /*
Clemo 0:cb80470434eb 2 Copyright 2013 Paul Soulsby www.soulsbysynths.com
Clemo 0:cb80470434eb 3 This file is part of Atmegatron.
Clemo 0:cb80470434eb 4
Clemo 0:cb80470434eb 5 Atmegatron is free software: you can redistribute it and/or modify
Clemo 0:cb80470434eb 6 it under the terms of the GNU General Public License as published by
Clemo 0:cb80470434eb 7 the Free Software Foundation, either version 3 of the License, or
Clemo 0:cb80470434eb 8 (at your option) any later version.
Clemo 0:cb80470434eb 9
Clemo 0:cb80470434eb 10 Atmegatron is distributed in the hope that it will be useful,
Clemo 0:cb80470434eb 11 but WITHOUT ANY WARRANTY; without even the implied warranty of
Clemo 0:cb80470434eb 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
Clemo 0:cb80470434eb 13 GNU General Public License for more details.
Clemo 0:cb80470434eb 14
Clemo 0:cb80470434eb 15 You should have received a copy of the GNU General Public License
Clemo 0:cb80470434eb 16 along with Atmegatron. If not, see <http://www.gnu.org/licenses/>.
Clemo 0:cb80470434eb 17 */
Clemo 0:cb80470434eb 18
Clemo 0:cb80470434eb 19 //******UNIPOLAR ENVELOPE - for amplitude***********
Clemo 0:cb80470434eb 20
Clemo 0:cb80470434eb 21 #include "atmegatron.h"
Clemo 0:cb80470434eb 22
Clemo 0:cb80470434eb 23 //lets and gets
Clemo 0:cb80470434eb 24 int aenv_A = 0; //attack (in ticks)
Clemo 0:cb80470434eb 25 int aenv_D = 0; //decay (in ticks)
Clemo 0:cb80470434eb 26 byte aenv_S = 255; //sustain (0-255)
Clemo 0:cb80470434eb 27 int aenv_R = 0; //release (in ticks)
Clemo 0:cb80470434eb 28 byte aenv_level = 0; //current output level (0-255)
Clemo 0:cb80470434eb 29
Clemo 0:cb80470434eb 30 //local variables
Clemo 0:cb80470434eb 31 unsigned long aenv_curtick; //current tick through env shape
Clemo 0:cb80470434eb 32 unsigned long aenv_starttick; //tick that env started at
Clemo 0:cb80470434eb 33 byte aenv_curstate = 0; //0 = off, 1 = triggering, 2 = holding, 3 = releasing
Clemo 0:cb80470434eb 34 boolean aenv_changed = true; //used to only calc Env when it's been triggered
Clemo 0:cb80470434eb 35 byte aenv_Rstart = 0; //incase key up before decay finishes
Clemo 0:cb80470434eb 36
Clemo 0:cb80470434eb 37 // lets and gets
Clemo 0:cb80470434eb 38
Clemo 0:cb80470434eb 39 //set attack (in ticks)
Clemo 0:cb80470434eb 40 void Aenv_Let_A(int newA){
Clemo 0:cb80470434eb 41 if (newA!=aenv_A){
Clemo 0:cb80470434eb 42 aenv_A = newA;
Clemo 0:cb80470434eb 43 aenv_changed = true;
Clemo 0:cb80470434eb 44 }
Clemo 0:cb80470434eb 45 }
Clemo 0:cb80470434eb 46
Clemo 0:cb80470434eb 47
Clemo 0:cb80470434eb 48 int Aenv_Get_A(void)
Clemo 0:cb80470434eb 49 {
Clemo 0:cb80470434eb 50 return aenv_A;
Clemo 0:cb80470434eb 51 }
Clemo 0:cb80470434eb 52
Clemo 0:cb80470434eb 53
Clemo 0:cb80470434eb 54 //set decay (in ticks)
Clemo 0:cb80470434eb 55 void Aenv_Let_D(int newD)
Clemo 0:cb80470434eb 56 {
Clemo 0:cb80470434eb 57 if (newD!=aenv_D){
Clemo 0:cb80470434eb 58 aenv_D = newD;
Clemo 0:cb80470434eb 59 aenv_changed = true;
Clemo 0:cb80470434eb 60 }
Clemo 0:cb80470434eb 61 }
Clemo 0:cb80470434eb 62
Clemo 0:cb80470434eb 63
Clemo 0:cb80470434eb 64 int Aenv_Get_D(void)
Clemo 0:cb80470434eb 65 {
Clemo 0:cb80470434eb 66 return aenv_D;
Clemo 0:cb80470434eb 67 }
Clemo 0:cb80470434eb 68
Clemo 0:cb80470434eb 69
Clemo 0:cb80470434eb 70 //set sustain (0-255)
Clemo 0:cb80470434eb 71 void Aenv_Let_S(byte newS)
Clemo 0:cb80470434eb 72 {
Clemo 0:cb80470434eb 73 if (newS!=aenv_S){
Clemo 0:cb80470434eb 74 aenv_S = newS;
Clemo 0:cb80470434eb 75 aenv_changed = true;
Clemo 0:cb80470434eb 76 }
Clemo 0:cb80470434eb 77 }
Clemo 0:cb80470434eb 78
Clemo 0:cb80470434eb 79
Clemo 0:cb80470434eb 80 byte Aenv_Get_S(void)
Clemo 0:cb80470434eb 81 {
Clemo 0:cb80470434eb 82 return aenv_S;
Clemo 0:cb80470434eb 83 }
Clemo 0:cb80470434eb 84
Clemo 0:cb80470434eb 85
Clemo 0:cb80470434eb 86 //set release (in ticks)
Clemo 0:cb80470434eb 87 void Aenv_Let_R(int newR)
Clemo 0:cb80470434eb 88 {
Clemo 0:cb80470434eb 89 if (newR!=aenv_R){
Clemo 0:cb80470434eb 90 aenv_R = newR;
Clemo 0:cb80470434eb 91 aenv_changed = true;
Clemo 0:cb80470434eb 92 }
Clemo 0:cb80470434eb 93 }
Clemo 0:cb80470434eb 94
Clemo 0:cb80470434eb 95
Clemo 0:cb80470434eb 96 int Aenv_Get_R(void)
Clemo 0:cb80470434eb 97 {
Clemo 0:cb80470434eb 98 return aenv_R;
Clemo 0:cb80470434eb 99 }
Clemo 0:cb80470434eb 100
Clemo 0:cb80470434eb 101
Clemo 0:cb80470434eb 102 //get current state of env (0 = off, 1 = triggering, 2 = holding, 3 = releasing)
Clemo 0:cb80470434eb 103 byte Aenv_Get_State()
Clemo 0:cb80470434eb 104 {
Clemo 0:cb80470434eb 105 return aenv_curstate;
Clemo 0:cb80470434eb 106 }
Clemo 0:cb80470434eb 107
Clemo 0:cb80470434eb 108
Clemo 0:cb80470434eb 109 //get current level of env (0-255)
Clemo 0:cb80470434eb 110 byte Aenv_Get_Level(void)
Clemo 0:cb80470434eb 111 {
Clemo 0:cb80470434eb 112 return aenv_level;
Clemo 0:cb80470434eb 113 }
Clemo 0:cb80470434eb 114
Clemo 0:cb80470434eb 115
Clemo 0:cb80470434eb 116 //ENVELOPE MEAT
Clemo 0:cb80470434eb 117 //trigger the (start of) envelope
Clemo 0:cb80470434eb 118 void AEnv_Trigger(void)
Clemo 0:cb80470434eb 119 {
Clemo 0:cb80470434eb 120 aenv_curtick = 0; //reset curtick
Clemo 0:cb80470434eb 121 aenv_starttick = master_tick; //set starttick = master tick
Clemo 0:cb80470434eb 122 aenv_curstate = 1; //set state to attack
Clemo 0:cb80470434eb 123 aenv_changed = true; //so calcval does something
Clemo 0:cb80470434eb 124 }
Clemo 0:cb80470434eb 125
Clemo 0:cb80470434eb 126
Clemo 0:cb80470434eb 127 //trigger release stage of envelope
Clemo 0:cb80470434eb 128 void AEnv_Release(void)
Clemo 0:cb80470434eb 129 {
Clemo 0:cb80470434eb 130 aenv_curtick = 0; //reset curtick
Clemo 0:cb80470434eb 131 aenv_starttick = master_tick; //set starttick = master tick
Clemo 0:cb80470434eb 132 aenv_curstate = 3; //set state to release
Clemo 0:cb80470434eb 133 aenv_Rstart = aenv_level; //set release start level = current level. This may NOT be sustain level, if still in decay stage
Clemo 0:cb80470434eb 134 aenv_changed = true; //so calcval does something
Clemo 0:cb80470434eb 135 }
Clemo 0:cb80470434eb 136
Clemo 0:cb80470434eb 137
Clemo 0:cb80470434eb 138 //calculate env output level
Clemo 0:cb80470434eb 139 void AEnv_CalcVal(void)
Clemo 0:cb80470434eb 140 {
Clemo 0:cb80470434eb 141 if (aenv_changed==true){ //is envelope actually doing something?
Clemo 0:cb80470434eb 142 switch (aenv_curstate){
Clemo 0:cb80470434eb 143 case 0: //idle
Clemo 0:cb80470434eb 144 aenv_level = 0;
Clemo 0:cb80470434eb 145 aenv_changed = false;
Clemo 0:cb80470434eb 146 break;
Clemo 0:cb80470434eb 147 case 1: //triggering
Clemo 0:cb80470434eb 148 aenv_curtick = master_tick - aenv_starttick; //update tick
Clemo 0:cb80470434eb 149 if (aenv_curtick>=aenv_A+aenv_D){ //if attack + decay ticks passed, then onto sustain
Clemo 0:cb80470434eb 150 aenv_level = aenv_S;
Clemo 0:cb80470434eb 151 aenv_curstate = 2;
Clemo 0:cb80470434eb 152 }
Clemo 0:cb80470434eb 153 else if (aenv_curtick>=aenv_A){ //if attack ticks passed, then onto decay
Clemo 0:cb80470434eb 154 aenv_level = map(aenv_curtick,aenv_A,aenv_A+aenv_D,255,aenv_S);
Clemo 0:cb80470434eb 155 }
Clemo 0:cb80470434eb 156 else{
Clemo 0:cb80470434eb 157 aenv_level = map(aenv_curtick,0,aenv_A,0,255); //otherwise must be doing attack
Clemo 0:cb80470434eb 158 }
Clemo 0:cb80470434eb 159 break;
Clemo 0:cb80470434eb 160 case 2: //holding
Clemo 0:cb80470434eb 161 aenv_level = aenv_S; //make sure level = sustain level
Clemo 0:cb80470434eb 162 aenv_changed = false; //only need to do this once
Clemo 0:cb80470434eb 163 break;
Clemo 0:cb80470434eb 164 case 3:
Clemo 0:cb80470434eb 165 aenv_curtick = master_tick - aenv_starttick; //releasing
Clemo 0:cb80470434eb 166 if (aenv_curtick>=aenv_R){ //if release ticks passed, then go back to idle
Clemo 0:cb80470434eb 167 aenv_level = 0;
Clemo 0:cb80470434eb 168 aenv_curstate = 0;
Clemo 0:cb80470434eb 169 }
Clemo 0:cb80470434eb 170 else{ //otherwise must be releasing
Clemo 0:cb80470434eb 171 aenv_level = map(aenv_curtick,0,aenv_R,aenv_Rstart,0);
Clemo 0:cb80470434eb 172 }
Clemo 0:cb80470434eb 173 break;
Clemo 0:cb80470434eb 174 }
Clemo 0:cb80470434eb 175 }
Clemo 0:cb80470434eb 176 }