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 "MessageTable.h"
#include "PdGraph.h"

#define DEFAULT_BUFFER_LENGTH 1024

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

MessageTable::MessageTable(pd::Message *init_message, PdGraph *graph) : RemoteMessageReceiver(0, 0, graph) {
  if (init_message->is_symbol(0)) {
    name = utils::copy_string(init_message->get_symbol(0));
    // by default, the buffer length is 1024. The buffer should never be NULL.
    bufferLength = init_message->is_float(1) ? (int) init_message->get_float(1) : DEFAULT_BUFFER_LENGTH;
    buffer = (float *) calloc(bufferLength, sizeof(float));
  } else {
    name = NULL;
    buffer = NULL;
    bufferLength = 0;
    graph->print_err("Object \"table\" must be initialised with a name.");
  }
}

MessageTable::~MessageTable() {
  free(name);
  free(buffer);
}

float *MessageTable::getBuffer(int *bufferLength) {
  *bufferLength = this->bufferLength;
  return buffer;
}

float *MessageTable::resizeBuffer(int newBufferLength) {
  if (newBufferLength > 0) {
    // the new buffer length must be positive
    buffer = (float *) realloc(buffer, newBufferLength * sizeof(float));
    if (newBufferLength > bufferLength) {
      // clear the new portion of the buffer
      memset(buffer+bufferLength, 0, (newBufferLength-bufferLength) * sizeof(float));
    }
    bufferLength = newBufferLength;
    // NOTE(mhroth): this code does not check to see if the returned buffer from realloc
    // is non-NULL. It assumes that realloc is always successful. This is slightly dangerous and
    // could lead to problems.
  }
  return buffer;
}

void MessageTable::process_message(int inlet_index, pd::Message *message) {
  // TODO(mhroth): process all of the commands which can be sent to tables
  if (message->is_symbol_str(0, "read")) {
    if (message->is_symbol_str(1))  {
      // read the file and fill the table
    }
  } else if (message->is_symbol_str(0, "write")) {
    // write the contents of the table to file
  } else if (message->is_symbol_str(0, "normalize")) {
    // normalise the contents of the table to the given value. Default to 1.
    #if __APPLE__
    float sum = 0.0f;
    vDSP_sve(buffer, 1, &sum, bufferLength);
    if (sum != 0.0f) {
      // ensure that element do not change sign during normalisation
      sum = fabsf(sum) / (message->is_float(1) ? message->get_float(1) : 1.0f);
      vDSP_vsdiv(buffer, 1, &sum, buffer, 1, bufferLength);
    }
    #else
    float sum = 0.0f;
    for (int i = 0; i < bufferLength; i++) {
      sum += buffer[i];
    }
    if (sum != 0.0f) {
      sum = fabsf(sum) / (message->is_float(1) ? message->get_float(1) : 1.0f);
      for (int i = 0; i < bufferLength; i++) {
        buffer[i] /= sum;
      }
    }
    #endif
  } else if (message->is_symbol_str(0, "resize")) {
    if (message->is_float(1)) {
      int newBufferLength = (int) message->get_float(1);
      resizeBuffer(newBufferLength);
    }
  }
}