This is a part of the Kinetiszer project.
distortion.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?
User | Revision | Line number | New 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 | // Very simple clipping distortion |
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 | byte dist_amt; |
Clemo | 0:cb80470434eb | 25 | |
Clemo | 0:cb80470434eb | 26 | |
Clemo | 0:cb80470434eb | 27 | void Distortion_Let_Amt(byte newamt) |
Clemo | 0:cb80470434eb | 28 | { |
Clemo | 0:cb80470434eb | 29 | dist_amt = newamt; |
Clemo | 0:cb80470434eb | 30 | } |
Clemo | 0:cb80470434eb | 31 | |
Clemo | 0:cb80470434eb | 32 | |
Clemo | 0:cb80470434eb | 33 | byte Distortion_Get_Amt(void) |
Clemo | 0:cb80470434eb | 34 | { |
Clemo | 0:cb80470434eb | 35 | return dist_amt; |
Clemo | 0:cb80470434eb | 36 | } |
Clemo | 0:cb80470434eb | 37 | |
Clemo | 0:cb80470434eb | 38 | |
Clemo | 0:cb80470434eb | 39 | //process the wavetable |
Clemo | 0:cb80470434eb | 40 | void Distortion_Process(void) |
Clemo | 0:cb80470434eb | 41 | { |
Clemo | 0:cb80470434eb | 42 | byte i; |
Clemo | 0:cb80470434eb | 43 | int s; |
Clemo | 0:cb80470434eb | 44 | for (i=0; i<WAVE_LEN; i++) //cycle through wavetable |
Clemo | 0:cb80470434eb | 45 | { |
Clemo | 0:cb80470434eb | 46 | s = (int)Wave_Get_Process(i); //get wavetable sample |
Clemo | 0:cb80470434eb | 47 | s = s << dist_amt; //shift by dist_amt bits (0-7) |
Clemo | 0:cb80470434eb | 48 | if (s > 127) //clip sample if necessary |
Clemo | 0:cb80470434eb | 49 | { |
Clemo | 0:cb80470434eb | 50 | s = 127; |
Clemo | 0:cb80470434eb | 51 | } |
Clemo | 0:cb80470434eb | 52 | else if (s < -128) |
Clemo | 0:cb80470434eb | 53 | { |
Clemo | 0:cb80470434eb | 54 | s = -128; |
Clemo | 0:cb80470434eb | 55 | } |
Clemo | 0:cb80470434eb | 56 | Wave_Let_Process(i, (sample_t)s); //write back to wavetable |
Clemo | 0:cb80470434eb | 57 | } |
Clemo | 0:cb80470434eb | 58 | } |
Clemo | 0:cb80470434eb | 59 |