purezen 0.0.2

Runtime for the Pure Data (Pd) audio programming language, implemented as an extensible audio library allowing full control over signal processing, message passing, and graph manipulation. Pure Data is a graph-based programming language environment creating interactive music and multimedia works.
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/*
 *  Copyright 2009,2010 Reality Jockey, Ltd.
 *                 info@rjdj.me
 *                 http://rjdj.me/
 * 
 *  This file is part of ZenGarden.
 *
 *  ZenGarden is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  ZenGarden is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Lesser General Public License for more details.
 *  
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with ZenGarden.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include "ArrayArithmetic.h"
#include "DspLine.h"
#include "PdGraph.h"

message::Object *DspLine::new_object(pd::Message *init_message, PdGraph *graph) {
  return new DspLine(init_message, graph);
}

DspLine::DspLine(pd::Message *init_message, PdGraph *graph) : DspObject(2, 0, 0, 1, graph) {
  target = 0.0f;
  slope = 0.0f;
  numSamplesToTarget = 0.0f;
  lastOutputSample = 0.0f;
}

DspLine::~DspLine() {
  // nothing to do
}

void DspLine::process_message(int inlet_index, pd::Message *message) {
  if (inlet_index == 0) { // not sure what the right inlet is for
    switch (message->get_num_elements()) {
      case 0: {
        break; // nothing to do
      }
      case 1: {
        // jump to value
        if (message->is_float(0)) {
          target = message->get_float(0);
          lastOutputSample = target;
          slope = 0.0f;
          numSamplesToTarget = 0.0f;
        }
        break;
      }
      default: { // at least two inputs
        // new ramp
        if (message->is_float(0) && message->is_float(1)) {
          target = message->get_float(0);
          float timeToTargetMs = message->get_float(1); // no negative time to targets!
          numSamplesToTarget = utils::millisecondsToSamples(
              (timeToTargetMs < 1.0f) ? 1.0f : timeToTargetMs, graph->get_sample_rate());
          slope = (target - lastOutputSample) / numSamplesToTarget;
        }
        break;
      }
    }
  }
}

void DspLine::processDspWithIndex(int fromIndex, int toIndex) {
  if (numSamplesToTarget <= 0.0f) { // if we have already reached the target
    int n = toIndex - fromIndex;
    if (n > 0) { // n may be zero
      ArrayArithmetic::fill(dspBufferAtOutlet[0], target, fromIndex, toIndex);
      lastOutputSample = target;
    }
  } else {
    // the number of samples to be processed this iteration
    int n = toIndex - fromIndex;
    if (n > 0) { // n may be zero
      // if there is anything to process at all (several messages may be received at once)
      if (numSamplesToTarget < n) {
        int targetIndexInt = fromIndex + numSamplesToTarget;
        #if __APPLE__
        vDSP_vramp(&lastOutputSample, &slope, dspBufferAtOutlet[0]+fromIndex, 1, targetIndexInt-fromIndex);
        vDSP_vfill(&target, dspBufferAtOutlet[0]+targetIndexInt, 1, toIndex-targetIndexInt);
        #else
        // if we will process more samples than we have remaining to the target
        // i.e., if we will arrive at the target while processing
        dspBufferAtOutlet[0][fromIndex] = lastOutputSample;
        for (int i = fromIndex+1; i < targetIndexInt; i++) {
          dspBufferAtOutlet[0][i] = dspBufferAtOutlet[0][i-1] + slope;
        }
        for (int i = targetIndexInt; i < toIndex; i++) {
          dspBufferAtOutlet[0][i] = target;
        }
        #endif
        lastOutputSample = target;
        numSamplesToTarget = 0;
      } else {
        // if the target is far off
        #if __APPLE__
        vDSP_vramp(&lastOutputSample, &slope, dspBufferAtOutlet[0]+fromIndex, 1, n);
        #else
        dspBufferAtOutlet[0][fromIndex] = lastOutputSample;
        for (int i = fromIndex+1; i < toIndex; i++) {
          dspBufferAtOutlet[0][i] = dspBufferAtOutlet[0][i-1] + slope;
        }
        #endif
        lastOutputSample = dspBufferAtOutlet[0][toIndex-1] + slope;
        numSamplesToTarget -= n;
      }
    }
  }
}