gtk2_ardour/tempo_lines.cc

   1 /*
   2     Copyright (C) 2002-2007 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 <libgnomecanvasmm/canvas.h>
  21 #include <libgnomecanvasmm/group.h>
  22 #include "tempo_lines.h"
  23 #include "ardour_ui.h"
  24
  25 using namespace std;
  26
  27 #define MAX_CACHED_LINES 128
  28
  29 TempoLines::TempoLines(ArdourCanvas::Canvas& canvas, ArdourCanvas::Group* group, double screen_height)
  30         : _canvas(canvas)
  31         , _group(group)
  32         , _clean_left(DBL_MAX)
  33         , _clean_right(0.0)
  34         , _height(screen_height)
  35 {
  36 }
  37
  38 void
  39 TempoLines::tempo_map_changed()
  40 {
  41         _clean_left = DBL_MAX;
  42         _clean_right = 0.0;
  43
  44         double_t d = 1.0;
  45         // TODO: Dirty/slow, but 'needed' for zoom :(
  46         for (Lines::iterator i = _lines.begin(); i != _lines.end(); d += 1.0) {
  47                 Lines::iterator next = i;
  48                 ++next;
  49                 i->second->property_x1() = - d;
  50                 i->second->property_x2() = - d;
  51                 _lines.erase(i);
  52                 _lines.insert(make_pair(- d, i->second));
  53                 i = next;
  54         }
  55 }
  56
  57 void
  58 TempoLines::show ()
  59 {
  60         for (Lines::iterator i = _lines.begin(); i != _lines.end(); ++i) {
  61                 i->second->show();
  62         }
  63 }
  64
  65 void
  66 TempoLines::hide ()
  67 {
  68         for (Lines::iterator i = _lines.begin(); i != _lines.end(); ++i) {
  69                 i->second->hide();
  70         }
  71 }
  72
  73 void
  74 TempoLines::draw (const ARDOUR::TempoMap::BBTPointList::const_iterator& begin,
  75                   const ARDOUR::TempoMap::BBTPointList::const_iterator& end,
  76                   double frames_per_unit)
  77 {
  78         ARDOUR::TempoMap::BBTPointList::const_iterator i;
  79         ArdourCanvas::SimpleLine *line = NULL;
  80         gdouble xpos;
  81         double who_cares;
  82         double x1, x2, y1, beat_density;
  83
  84         uint32_t beats = 0;
  85         uint32_t bars = 0;
  86         uint32_t color;
  87
  88         const size_t needed = distance (begin, end);
  89
  90         _canvas.get_scroll_region (x1, y1, x2, who_cares);
  91
  92         /* get the first bar spacing */
  93
  94         i = end;
  95         i--;
  96         bars = (*i).bar - (*begin).bar;
  97         beats = distance (begin, end) - bars;
  98
  99         beat_density = (beats * 10.0f) / _canvas.get_width ();
 100
 101         if (beat_density > 4.0f) {
 102                 /* if the lines are too close together, they become useless */
 103                 tempo_map_changed();
 104                 return;
 105         }
 106
 107         xpos = rint(((framepos_t)(*i).frame) / (double)frames_per_unit);
 108         const double needed_right = xpos;
 109
 110         i = begin;
 111
 112         xpos = rint(((framepos_t)(*i).frame) / (double)frames_per_unit);
 113         const double needed_left = xpos;
 114
 115         Lines::iterator left = _lines.lower_bound(xpos); // first line >= xpos
 116
 117         bool exhausted = (left == _lines.end());
 118         Lines::iterator li = left;
 119         if (li != _lines.end())
 120                 line = li->second;
 121
 122         // Tempo map hasn't changed and we're entirely within a clean
 123         // range, don't need to do anything.  Yay.
 124         if (needed_left >= _clean_left && needed_right <= _clean_right) {
 125                 //cout << endl << "*** LINE CACHE PERFECT HIT" << endl;
 126                 return;
 127         }
 128
 129         //cout << endl << "*** LINE CACHE MISS" << endl;
 130
 131         bool inserted_last_time = true;
 132         bool invalidated = false;
 133
 134         for (i = begin; i != end; ++i) {
 135
 136                 if ((*i).is_bar()) {
 137                         color = ARDOUR_UI::config()->canvasvar_MeasureLineBar.get();
 138                 } else {
 139                         if (beat_density > 2.0) {
 140                                 continue; /* only draw beat lines if the gaps between beats are large. */
 141                         }
 142                         color = ARDOUR_UI::config()->canvasvar_MeasureLineBeat.get();
 143                 }
 144
 145                 xpos = rint(((framepos_t)(*i).frame) / (double)frames_per_unit);
 146
 147                 if (inserted_last_time && !_lines.empty()) {
 148                         li = _lines.lower_bound(xpos); // first line >= xpos
 149                 }
 150
 151                 line = (li != _lines.end()) ? li->second : NULL;
 152                 assert(!line || line->property_x1() == li->first);
 153
 154                 Lines::iterator next = li;
 155                 if (next != _lines.end())
 156                         ++next;
 157
 158                 exhausted = (next == _lines.end());
 159
 160                 // Hooray, line is perfect
 161                 if (line && line->property_x1() == xpos) {
 162                         if (li != _lines.end())
 163                                 ++li;
 164
 165                         line->property_color_rgba() = color;
 166                         inserted_last_time = false; // don't search next time
 167
 168                         // Use existing line, moving if necessary
 169                 } else if (!exhausted) {
 170                         Lines::iterator steal = _lines.end();
 171                         --steal;
 172
 173                         // Steal from the right
 174                         if (left->first > needed_left && li != steal && steal->first > needed_right) {
 175                                 //cout << "*** STEALING FROM RIGHT" << endl;
 176                                 line = steal->second;
 177                                 _lines.erase(steal);
 178                                 line->property_x1() = xpos;
 179                                 line->property_x2() = xpos;
 180                                 line->property_color_rgba() = color;
 181                                 _lines.insert(make_pair(xpos, line));
 182                                 inserted_last_time = true; // search next time
 183                                 invalidated = true;
 184
 185                                 // Shift clean range left
 186                                 _clean_left = min(_clean_left, xpos);
 187                                 _clean_right = min(_clean_right, steal->first);
 188
 189                                 // Move this line to where we need it
 190                         } else {
 191                                 Lines::iterator existing = _lines.find(xpos);
 192                                 if (existing != _lines.end()) {
 193                                         //cout << "*** EXISTING LINE" << endl;
 194                                         li = existing;
 195                                         li->second->property_color_rgba() = color;
 196                                         inserted_last_time = false; // don't search next time
 197                                 } else {
 198                                         //cout << "*** MOVING LINE" << endl;
 199                                         const double x1 = line->property_x1();
 200                                         const bool was_clean = x1 >= _clean_left && x1 <= _clean_right;
 201                                         invalidated = invalidated || was_clean;
 202                                         // Invalidate clean portion (XXX: too harsh?)
 203                                         _clean_left  = needed_left;
 204                                         _clean_right = needed_right;
 205                                         _lines.erase(li);
 206                                         line->property_color_rgba() = color;
 207                                         line->property_x1() = xpos;
 208                                         line->property_x2() = xpos;
 209                                         _lines.insert(make_pair(xpos, line));
 210                                         inserted_last_time = true; // search next time
 211                                 }
 212                         }
 213
 214                         // Create a new line
 215                 } else if (_lines.size() < needed || _lines.size() < MAX_CACHED_LINES) {
 216                         //cout << "*** CREATING LINE" << endl;
 217                         assert(_lines.find(xpos) == _lines.end());
 218                         line = new ArdourCanvas::SimpleLine (*_group);
 219                         line->property_x1() = xpos;
 220                         line->property_x2() = xpos;
 221                         line->property_y1() = 0.0;
 222                         line->property_y2() = _height;
 223                         line->property_color_rgba() = color;
 224                         _lines.insert(make_pair(xpos, line));
 225                         inserted_last_time = true;
 226
 227                         // Steal from the left
 228                 } else {
 229                         //cout << "*** STEALING FROM LEFT" << endl;
 230                         assert(_lines.find(xpos) == _lines.end());
 231                         Lines::iterator steal = _lines.begin();
 232                         line = steal->second;
 233                         _lines.erase(steal);
 234                         line->property_color_rgba() = color;
 235                         line->property_x1() = xpos;
 236                         line->property_x2() = xpos;
 237                         _lines.insert(make_pair(xpos, line));
 238                         inserted_last_time = true; // search next time
 239                         invalidated = true;
 240
 241                         // Shift clean range right
 242                         _clean_left = max(_clean_left, steal->first);
 243                         _clean_right = max(_clean_right, xpos);
 244                 }
 245         }
 246
 247         // Extend range to what we've 'fixed'
 248         if (!invalidated) {
 249                 _clean_left  = min(_clean_left, needed_left);
 250                 _clean_right = max(_clean_right, needed_right);
 251         }
 252 }
 253