libs/ardour/progress.cc

   1 /*
   2     Copyright (C) 2010 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include <cassert>
  21 #include <iostream>
  22 #include "ardour/progress.h"
  23
  24 using namespace std;
  25
  26 ARDOUR::Progress::Progress ()
  27         : _cancelled (false)
  28 {
  29         descend (1);
  30 }
  31
  32 /** Descend down one level in terms of progress reporting; e.g. if
  33  *  there is a task which is split up into N subtasks, each of which
  34  *  report their progress from 0 to 100%, call descend() before executing
  35  *  each subtask, and ascend() afterwards to ensure that overall progress
  36  *  is reported correctly.
  37  *
  38  *  @param p Percentage (from 0 to 1) of the current task to allocate to the subtask.
  39  */
  40 void
  41 ARDOUR::Progress::descend (float a)
  42 {
  43         _stack.push_back (Level (a));
  44 }
  45
  46 void
  47 ARDOUR::Progress::ascend ()
  48 {
  49         assert (!_stack.empty ());
  50         float const a = _stack.back().allocation;
  51         _stack.pop_back ();
  52         _stack.back().normalised += a;
  53 }
  54
  55 /** Set the progress of the current task.
  56  *  @param p Progress (from 0 to 1)
  57  */
  58 void
  59 ARDOUR::Progress::set_progress (float p)
  60 {
  61         assert (!_stack.empty ());
  62
  63         _stack.back().normalised = p;
  64
  65         float overall = 0;
  66         float factor = 1;
  67         for (list<Level>::iterator i = _stack.begin(); i != _stack.end(); ++i) {
  68                 factor *= i->allocation;
  69                 overall += i->normalised * factor;
  70         }
  71
  72         set_overall_progress (overall);
  73 }
  74
  75 void
  76 ARDOUR::Progress::cancel ()
  77 {
  78         _cancelled = true;
  79 }
  80
  81 bool
  82 ARDOUR::Progress::cancelled () const
  83 {
  84         return _cancelled;
  85 }