Diff: POKITTO_LIBS/Synth/Synth_wavefuncs.cpp

Revision:

0:e8b8f36b4505

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/POKITTO_LIBS/Synth/Synth_wavefuncs.cpp	Mon Sep 18 11:47:51 2017 +0000
@@ -0,0 +1,108 @@
+/**************************************************************************/
+/*!
+    @file     Synth_wavefuncs.cpp
+    @author   Jonne Valola
+
+    @section LICENSE
+
+    Software License Agreement (BSD License)
+
+    Copyright (c) 2016, Jonne Valola
+    All rights reserved.
+
+    Redistribution and use in source and binary forms, with or without
+    modification, are permitted provided that the following conditions are met:
+    1. Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in the
+    documentation and/or other materials provided with the distribution.
+    3. Neither the name of the copyright holders nor the
+    names of its contributors may be used to endorse or promote products
+    derived from this software without specific prior written permission.
+
+    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
+    EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+    WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+    DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
+    DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+    ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+/**************************************************************************/
+
+#include "Synth.h"
+
+uint16_t noiseval, noiseval2;
+
+void waveoff(OSC* o); void sqwave(OSC* o); void sawwave(OSC* o); void triwave(OSC* o); void noise(OSC* o); void tonenoise(OSC* o); void sample(OSC* o);
+void noADSR(OSC* o); void attackFunc(OSC* o); void decayFunc(OSC* o); void releaseFunc(OSC* o);
+void mix1(); void mix2(); void mix3(); void updateEnvelopes();
+
+waveFunction Farr []  = {waveoff, sqwave, sawwave, triwave, noise, tonenoise};
+envFunction Earr [] = {noADSR, attackFunc, decayFunc, releaseFunc};
+mixFunction Marr [] = {updateEnvelopes,mix3,mix2,mix1}; // counts down
+mixFunction HWMarr [] = {updateEnvelopes,mix3,mix2,mix1}; // counts down
+
+/** SOUND FUNCTIONS **/
+
+void waveoff(OSC* o){
+  o->output = 0;
+}
+
+void sqwave(OSC* o){
+// square. If bit 16 set, its 2nd half of cycle and then output. if not, silence.
+ if (o->count & 0x8000) o->output = 0;
+ else  o->output = 0xFFFF;
+}
+
+void sawwave(OSC* o){
+ // saw is just twice the count, so it happens 2 times in a cycle.
+ o->output = o->count << 1; // simple, eh ?
+}
+
+void triwave(OSC* o){
+    // exploit the fact that above 0x7FFF bit 16 will be set (ie. when on second side of cycle)
+    if (o->count & 0x8000) o->output = (~o->count) << 1; // counts down because complement goes other way
+    else o->output = o->count << 1; // count up on first side of cycle
+}
+
+void noise(OSC* o){
+  // Standard libc random gives 10-12 fps
+  // Xorshift16 gives 32-39 fps
+  // Xorshift8 gives
+
+  if (o->count > 0x8000) {
+    o->output = noiseval2;
+    //noiseval = random(0,0xFFFF);
+    noiseval = xorshift16();
+    //noiseval = xorshift8()*256;
+  }
+  else  {
+    o->output = noiseval;
+    //noiseval2 = random(0,0xFFFF);
+    noiseval2 = xorshift16();
+    //noiseval2 = xorshift8()*256;
+  }
+}
+
+void tonenoise(OSC* o){
+  // square. If bit 16 set, its 2nd half of cycle and then output. if not, silence.
+ if (o->count & 0x8000) o->output = (xorshift16()>>6); //was 0
+ else  o->output = (xorshift16()>>1) + 0x4000;//random(0,0xFFFF);
+}
+
+void sample(OSC* o) {
+
+    /*if (o->samplepos > o->samplelength ) o->samplepos = 0;
+
+    if (o->count > o->wcycle) {
+        o->count=0;
+        if (o->output) o->output = 0;
+        //else o->output = o->output=pgm_read_byte((uint32_t)(sfxBike) + o->inccount);
+    }*/
+}
+