Subversion Repositories DIN Is Noise

/*
* fader.cc
* DIN Is Noise is copyright (c) 2006-2017 Jagannathan Sampath
* For more information, please visit http://dinisnoise.org/
*/

#include "fader.h"
#include "console.h"
#include "chrono.h"
#include "log.h"

fader::fader (float vs, float ve) {
  set (vs, ve, 0);
}

void fader::set (float vs, float ve, int _on, float dt) {

  start = vs;
  end = ve;
  delta = end - start;

  if (delta < 0) flip = 1; else flip = 0;

  alpha = 0;
  amount = start;

  delta_time = dt;

  on = _on;
  reached = !on;
  start_time = ui_clk();

}

int fader::eval () {

  if (on) {

    double dt = ui_clk() - start_time;

    if (dt >= delta_time) {

      if (reached) {
        on = 0;
        if (post != "") {
          cons (post);
          post = "";
        }
      } else {
        reached = 1;
        alpha = 1;
      }

    } else alpha = dt * 1.0f / delta_time;

    if (flip) amount = 1 - alpha; else amount = alpha;

  }

  return on;
}

void fader::restart () {
  on = 1;
  reached = 0;
  alpha = 0;
  start_time = ui_clk();
}

void fader::set_post (const std::string& pst) {
  post = pst;
}

float fader::value () {
  return (start + alpha * delta);
}