libs/canvas/wave_view.cc

   1 /*
   2     Copyright (C) 2011-2013 Paul Davis
   3     Author: Carl Hetherington <cth@carlh.net>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program; if not, write to the Free Software
  17     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18
  19 */
  20
  21 #include <cmath>
  22 #include <cairomm/cairomm.h>
  23
  24 #include <glibmm/threads.h>
  25
  26 #include "gtkmm2ext/utils.h"
  27 #include "gtkmm2ext/gui_thread.h"
  28
  29 #include "pbd/base_ui.h"
  30 #include "pbd/compose.h"
  31 #include "pbd/convert.h"
  32 #include "pbd/signals.h"
  33 #include "pbd/stacktrace.h"
  34
  35 #include "ardour/types.h"
  36 #include "ardour/dB.h"
  37 #include "ardour/lmath.h"
  38 #include "ardour/audioregion.h"
  39 #include "ardour/audiosource.h"
  40 #include "ardour/session.h"
  41
  42 #include "canvas/canvas.h"
  43 #include "canvas/colors.h"
  44 #include "canvas/debug.h"
  45 #include "canvas/utils.h"
  46 #include "canvas/wave_view.h"
  47
  48 #include "evoral/Range.hpp"
  49
  50 #include <gdkmm/general.h>
  51
  52 #include "gtkmm2ext/gui_thread.h"
  53
  54 using namespace std;
  55 using namespace ARDOUR;
  56 using namespace PBD;
  57 using namespace ArdourCanvas;
  58
  59 double WaveView::_global_gradient_depth = 0.6;
  60 bool WaveView::_global_logscaled = false;
  61 WaveView::Shape WaveView::_global_shape = WaveView::Normal;
  62 bool WaveView::_global_show_waveform_clipping = true;
  63 double WaveView::_clip_level = 0.98853;
  64
  65 WaveViewCache* WaveView::images = 0;
  66 gint WaveView::drawing_thread_should_quit = 0;
  67 Glib::Threads::Mutex WaveView::request_queue_lock;
  68 Glib::Threads::Cond WaveView::request_cond;
  69 Glib::Threads::Thread* WaveView::_drawing_thread = 0;
  70 WaveView::DrawingRequestQueue WaveView::request_queue;
  71
  72 PBD::Signal0<void> WaveView::VisualPropertiesChanged;
  73 PBD::Signal0<void> WaveView::ClipLevelChanged;
  74
  75 WaveView::WaveView (Canvas* c, boost::shared_ptr<ARDOUR::AudioRegion> region)
  76         : Item (c)
  77         , _region (region)
  78         , _channel (0)
  79         , _samples_per_pixel (0)
  80         , _height (64)
  81         , _show_zero (false)
  82         , _zero_color (0xff0000ff)
  83         , _clip_color (0xff0000ff)
  84         , _logscaled (_global_logscaled)
  85         , _shape (_global_shape)
  86         , _gradient_depth (_global_gradient_depth)
  87         , _shape_independent (false)
  88         , _logscaled_independent (false)
  89         , _gradient_depth_independent (false)
  90         , _amplitude_above_axis (1.0)
  91         , _region_amplitude (region->scale_amplitude ())
  92         , _start_shift (0.0)
  93         , _region_start (region->start())
  94         , get_image_in_thread (false)
  95         , always_get_image_in_thread (false)
  96         , rendered (false)
  97 {
  98         if (!images) {
  99                 images = new WaveViewCache;
 100         }
 101
 102         VisualPropertiesChanged.connect_same_thread (invalidation_connection, boost::bind (&WaveView::handle_visual_property_change, this));
 103         ClipLevelChanged.connect_same_thread (invalidation_connection, boost::bind (&WaveView::handle_clip_level_change, this));
 104
 105         ImageReady.connect (image_ready_connection, invalidator (*this), boost::bind (&WaveView::image_ready, this), gui_context());
 106 }
 107
 108 WaveView::WaveView (Item* parent, boost::shared_ptr<ARDOUR::AudioRegion> region)
 109         : Item (parent)
 110         , _region (region)
 111         , _channel (0)
 112         , _samples_per_pixel (0)
 113         , _height (64)
 114         , _show_zero (false)
 115         , _zero_color (0xff0000ff)
 116         , _clip_color (0xff0000ff)
 117         , _logscaled (_global_logscaled)
 118         , _shape (_global_shape)
 119         , _gradient_depth (_global_gradient_depth)
 120         , _shape_independent (false)
 121         , _logscaled_independent (false)
 122         , _gradient_depth_independent (false)
 123         , _amplitude_above_axis (1.0)
 124         , _region_amplitude (region->scale_amplitude ())
 125         , _start_shift (0.0)
 126         , _region_start (region->start())
 127         , get_image_in_thread (false)
 128         , always_get_image_in_thread (false)
 129         , rendered (false)
 130 {
 131         if (!images) {
 132                 images = new WaveViewCache;
 133         }
 134
 135         VisualPropertiesChanged.connect_same_thread (invalidation_connection, boost::bind (&WaveView::handle_visual_property_change, this));
 136         ClipLevelChanged.connect_same_thread (invalidation_connection, boost::bind (&WaveView::handle_clip_level_change, this));
 137
 138         ImageReady.connect (image_ready_connection, invalidator (*this), boost::bind (&WaveView::image_ready, this), gui_context());
 139 }
 140
 141 WaveView::~WaveView ()
 142 {
 143         invalidate_image_cache ();
 144 }
 145
 146 string
 147 WaveView::debug_name() const
 148 {
 149         return _region->name() + string (":") + PBD::to_string (_channel+1, std::dec);
 150 }
 151
 152 void
 153 WaveView::image_ready ()
 154 {
 155         DEBUG_TRACE (DEBUG::WaveView, string_compose ("queue draw for %1 at %2 (vis = %3 CR %4)\n", this, g_get_monotonic_time(), visible(), current_request));
 156         redraw ();
 157 }
 158
 159 void
 160 WaveView::set_always_get_image_in_thread (bool yn)
 161 {
 162         always_get_image_in_thread = yn;
 163 }
 164
 165 void
 166 WaveView::handle_visual_property_change ()
 167 {
 168         bool changed = false;
 169
 170         if (!_shape_independent && (_shape != global_shape())) {
 171                 _shape = global_shape();
 172                 changed = true;
 173         }
 174
 175         if (!_logscaled_independent && (_logscaled != global_logscaled())) {
 176                 _logscaled = global_logscaled();
 177                 changed = true;
 178         }
 179
 180         if (!_gradient_depth_independent && (_gradient_depth != global_gradient_depth())) {
 181                 _gradient_depth = global_gradient_depth();
 182                 changed = true;
 183         }
 184
 185         if (changed) {
 186                 begin_visual_change ();
 187                 invalidate_image_cache ();
 188                 end_visual_change ();
 189         }
 190 }
 191
 192 void
 193 WaveView::handle_clip_level_change ()
 194 {
 195         begin_visual_change ();
 196         invalidate_image_cache ();
 197         end_visual_change ();
 198 }
 199
 200 void
 201 WaveView::set_fill_color (Color c)
 202 {
 203         if (c != _fill_color) {
 204                 begin_visual_change ();
 205                 invalidate_image_cache ();
 206                 Fill::set_fill_color (c);
 207                 end_visual_change ();
 208         }
 209 }
 210
 211 void
 212 WaveView::set_outline_color (Color c)
 213 {
 214         if (c != _outline_color) {
 215                 begin_visual_change ();
 216                 invalidate_image_cache ();
 217                 Outline::set_outline_color (c);
 218                 end_visual_change ();
 219         }
 220 }
 221
 222 void
 223 WaveView::set_samples_per_pixel (double samples_per_pixel)
 224 {
 225         if (samples_per_pixel != _samples_per_pixel) {
 226                 begin_change ();
 227
 228                 invalidate_image_cache ();
 229                 _samples_per_pixel = samples_per_pixel;
 230                 _bounding_box_dirty = true;
 231
 232                 end_change ();
 233         }
 234 }
 235
 236 static inline float
 237 _log_meter (float power, double lower_db, double upper_db, double non_linearity)
 238 {
 239         return (power < lower_db ? 0.0 : pow((power-lower_db)/(upper_db-lower_db), non_linearity));
 240 }
 241
 242 static inline float
 243 alt_log_meter (float power)
 244 {
 245         return _log_meter (power, -192.0, 0.0, 8.0);
 246 }
 247
 248 void
 249 WaveView::set_clip_level (double dB)
 250 {
 251         const double clip_level = dB_to_coefficient (dB);
 252         if (clip_level != _clip_level) {
 253                 _clip_level = clip_level;
 254                 ClipLevelChanged ();
 255         }
 256 }
 257
 258 void
 259 WaveView::invalidate_image_cache ()
 260 {
 261         DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 invalidates image cache and cancels current request\n", this));
 262         cancel_my_render_request ();
 263         _current_image.reset ();
 264 }
 265
 266 void
 267 WaveView::compute_tips (PeakData const & peak, WaveView::LineTips& tips) const
 268 {
 269         const double effective_height  = _height;
 270
 271         /* remember: canvas (and cairo) coordinate space puts the origin at the upper left.
 272
 273            So, a sample value of 1.0 (0dbFS) will be computed as:
 274
 275                  (1.0 - 1.0) * 0.5 * effective_height
 276
 277            which evaluates to 0, or the top of the image.
 278
 279            A sample value of -1.0 will be computed as
 280
 281                 (1.0 + 1.0) * 0.5 * effective height
 282
 283            which evaluates to effective height, or the bottom of the image.
 284         */
 285
 286         const double pmax = (1.0 - peak.max) * 0.5 * effective_height;
 287         const double pmin = (1.0 - peak.min) * 0.5 * effective_height;
 288
 289         /* remember that the bottom of the image (pmin) has larger y-coordinates
 290            than the top (pmax).
 291         */
 292
 293         double spread = (pmin - pmax) * 0.5;
 294
 295         /* find the nearest pixel to the nominal center. */
 296         const double center = round (pmin - spread);
 297
 298         if (spread < 1.0) {
 299                 /* minimum distance between line ends is 1 pixel, and we want it "centered" on a pixel,
 300                    as per cairo single-pixel line issues.
 301
 302                    NOTE: the caller will not draw a line between these two points if the spread is
 303                    less than 2 pixels. So only the tips.top value matters, which is where we will
 304                    draw a single pixel as part of the outline.
 305                  */
 306                 tips.top = center;
 307                 tips.bot = center + 1.0;
 308         } else {
 309                 /* round spread above and below center to an integer number of pixels */
 310                 spread = round (spread);
 311                 /* top and bottom are located equally either side of the center */
 312                 tips.top = center - spread;
 313                 tips.bot = center + spread;
 314         }
 315
 316         tips.top = min (effective_height, max (0.0, tips.top));
 317         tips.bot = min (effective_height, max (0.0, tips.bot));
 318 }
 319
 320
 321 Coord
 322 WaveView::y_extent (double s) const
 323 {
 324         assert (_shape == Rectified);
 325         return floor ((1.0 - s) * _height);
 326 }
 327
 328 void
 329 WaveView::draw_absent_image (Cairo::RefPtr<Cairo::ImageSurface>& image, PeakData* _peaks, int n_peaks) const
 330 {
 331         Cairo::RefPtr<Cairo::ImageSurface> stripe = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, _height);
 332
 333         Cairo::RefPtr<Cairo::Context> stripe_context = Cairo::Context::create (stripe);
 334         stripe_context->set_antialias (Cairo::ANTIALIAS_NONE);
 335
 336         uint32_t stripe_separation = 150;
 337         double start = - floor (_height / stripe_separation) * stripe_separation;
 338         int stripe_x = 0;
 339
 340         while (start < n_peaks) {
 341
 342                 stripe_context->move_to (start, 0);
 343                 stripe_x = start + _height;
 344                 stripe_context->line_to (stripe_x, _height);
 345                 start += stripe_separation;
 346         }
 347
 348         stripe_context->set_source_rgba (1.0, 1.0, 1.0, 1.0);
 349         stripe_context->set_line_cap (Cairo::LINE_CAP_SQUARE);
 350         stripe_context->set_line_width(50);
 351         stripe_context->stroke();
 352
 353         Cairo::RefPtr<Cairo::Context> context = Cairo::Context::create (image);
 354
 355         context->set_source_rgba (1.0, 1.0, 0.0, 0.3);
 356         context->mask (stripe, 0, 0);
 357         context->fill ();
 358 }
 359
 360 struct ImageSet {
 361         Cairo::RefPtr<Cairo::ImageSurface> wave;
 362         Cairo::RefPtr<Cairo::ImageSurface> outline;
 363         Cairo::RefPtr<Cairo::ImageSurface> clip;
 364         Cairo::RefPtr<Cairo::ImageSurface> zero;
 365
 366         ImageSet() :
 367                 wave (0), outline (0), clip (0), zero (0) {}
 368 };
 369
 370 void
 371 WaveView::draw_image (Cairo::RefPtr<Cairo::ImageSurface>& image, PeakData* _peaks, int n_peaks, boost::shared_ptr<WaveViewThreadRequest> req) const
 372 {
 373
 374         ImageSet images;
 375
 376         images.wave = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, _height);
 377         images.outline = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, _height);
 378         images.clip = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, _height);
 379         images.zero = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, _height);
 380
 381         Cairo::RefPtr<Cairo::Context> wave_context = Cairo::Context::create (images.wave);
 382         Cairo::RefPtr<Cairo::Context> outline_context = Cairo::Context::create (images.outline);
 383         Cairo::RefPtr<Cairo::Context> clip_context = Cairo::Context::create (images.clip);
 384         Cairo::RefPtr<Cairo::Context> zero_context = Cairo::Context::create (images.zero);
 385         wave_context->set_antialias (Cairo::ANTIALIAS_NONE);
 386         outline_context->set_antialias (Cairo::ANTIALIAS_NONE);
 387         clip_context->set_antialias (Cairo::ANTIALIAS_NONE);
 388         zero_context->set_antialias (Cairo::ANTIALIAS_NONE);
 389
 390         boost::scoped_array<LineTips> tips (new LineTips[n_peaks]);
 391
 392         /* Clip level nominally set to -0.9dBFS to account for inter-sample
 393            interpolation possibly clipping (value may be too low).
 394
 395            We adjust by the region's own gain (but note: not by any gain
 396            automation or its gain envelope) so that clip indicators are closer
 397            to providing data about on-disk data. This multiplication is
 398            needed because the data we get from AudioRegion::read_peaks()
 399            has been scaled by scale_amplitude() already.
 400         */
 401
 402         const double clip_level = _clip_level * _region_amplitude;
 403
 404         if (_shape == WaveView::Rectified) {
 405
 406                 /* each peak is a line from the bottom of the waveview
 407                  * to a point determined by max (_peaks[i].max,
 408                  * _peaks[i].min)
 409                  */
 410
 411                 if (_logscaled) {
 412                         for (int i = 0; i < n_peaks; ++i) {
 413
 414                                 tips[i].bot = height() - 1.0;
 415                                 const double p = alt_log_meter (fast_coefficient_to_dB (max (fabs (_peaks[i].max), fabs (_peaks[i].min))));
 416                                 tips[i].top = y_extent (p);
 417                                 tips[i].spread = p * _height;
 418
 419                                 if (_peaks[i].max >= clip_level) {
 420                                         tips[i].clip_max = true;
 421                                 }
 422
 423                                 if (-(_peaks[i].min) >= clip_level) {
 424                                         tips[i].clip_min = true;
 425                                 }
 426                         }
 427
 428                 } else {
 429                         for (int i = 0; i < n_peaks; ++i) {
 430
 431                                 tips[i].bot = height() - 1.0;
 432                                 const double p = max(fabs (_peaks[i].max), fabs (_peaks[i].min));
 433                                 tips[i].top = y_extent (p);
 434                                 tips[i].spread = p * _height;
 435                                 if (p >= clip_level) {
 436                                         tips[i].clip_max = true;
 437                                 }
 438                         }
 439
 440                 }
 441
 442         } else {
 443
 444                 if (_logscaled) {
 445                         for (int i = 0; i < n_peaks; ++i) {
 446                                 PeakData p;
 447                                 p.max = _peaks[i].max;
 448                                 p.min = _peaks[i].min;
 449
 450                                 if (_peaks[i].max >= clip_level) {
 451                                         tips[i].clip_max = true;
 452                                 }
 453                                 if (-(_peaks[i].min) >= clip_level) {
 454                                         tips[i].clip_min = true;
 455                                 }
 456
 457                                 if (p.max > 0.0) {
 458                                         p.max = alt_log_meter (fast_coefficient_to_dB (p.max));
 459                                 } else if (p.max < 0.0) {
 460                                         p.max =-alt_log_meter (fast_coefficient_to_dB (-p.max));
 461                                 } else {
 462                                         p.max = 0.0;
 463                                 }
 464
 465                                 if (p.min > 0.0) {
 466                                         p.min = alt_log_meter (fast_coefficient_to_dB (p.min));
 467                                 } else if (p.min < 0.0) {
 468                                         p.min = -alt_log_meter (fast_coefficient_to_dB (-p.min));
 469                                 } else {
 470                                         p.min = 0.0;
 471                                 }
 472
 473                                 compute_tips (p, tips[i]);
 474                                 tips[i].spread = tips[i].bot - tips[i].top;
 475                         }
 476
 477                 } else {
 478                         for (int i = 0; i < n_peaks; ++i) {
 479                                 if (_peaks[i].max >= clip_level) {
 480                                         tips[i].clip_max = true;
 481                                 }
 482                                 if (-(_peaks[i].min) >= clip_level) {
 483                                         tips[i].clip_min = true;
 484                                 }
 485
 486                                 compute_tips (_peaks[i], tips[i]);
 487                                 tips[i].spread = tips[i].bot - tips[i].top;
 488                         }
 489
 490                 }
 491         }
 492
 493         if (req->should_stop()) {
 494                 return;
 495         }
 496
 497         Color alpha_one = rgba_to_color (0, 0, 0, 1.0);
 498
 499         set_source_rgba (wave_context, alpha_one);
 500         set_source_rgba (outline_context, alpha_one);
 501         set_source_rgba (clip_context, alpha_one);
 502         set_source_rgba (zero_context, alpha_one);
 503
 504         /* ensure single-pixel lines */
 505
 506         wave_context->set_line_width (1.0);
 507         wave_context->translate (0.5, 0.5);
 508
 509         outline_context->set_line_width (1.0);
 510         outline_context->translate (0.5, 0.5);
 511
 512         clip_context->set_line_width (1.0);
 513         clip_context->translate (0.5, 0.5);
 514
 515         zero_context->set_line_width (1.0);
 516         zero_context->translate (0.5, 0.5);
 517
 518         /* the height of the clip-indicator should be at most 7 pixels,
 519          * or 5% of the height of the waveview item.
 520          */
 521
 522         const double clip_height = min (7.0, ceil (_height * 0.05));
 523
 524         /* There are 3 possible components to draw at each x-axis position: the
 525            waveform "line", the zero line and an outline/clip indicator.  We
 526            have to decide which of the 3 to draw at each position, pixel by
 527            pixel. This makes the rendering less efficient but it is the only
 528            way I can see to do this correctly.
 529
 530            To avoid constant source swapping and stroking, we draw the components separately
 531            onto four alpha only image surfaces for use as a mask.
 532
 533            With only 1 pixel of spread between the top and bottom of the line,
 534            we just draw the upper outline/clip indicator.
 535
 536            With 2 pixels of spread, we draw the upper and lower outline clip
 537            indicators.
 538
 539            With 3 pixels of spread we draw the upper and lower outline/clip
 540            indicators and at least 1 pixel of the waveform line.
 541
 542            With 5 pixels of spread, we draw all components.
 543
 544            We can do rectified as two separate passes because we have a much
 545            easier decision regarding whether to draw the waveform line. We
 546            always draw the clip/outline indicators.
 547         */
 548
 549         if (_shape == WaveView::Rectified) {
 550
 551                 for (int i = 0; i < n_peaks; ++i) {
 552
 553                         /* waveform line */
 554
 555                         if (tips[i].spread >= 1.0) {
 556                                 wave_context->move_to (i, tips[i].top);
 557                                 wave_context->line_to (i, tips[i].bot);
 558                         }
 559
 560                         /* clip indicator */
 561
 562                         if (_global_show_waveform_clipping && (tips[i].clip_max || tips[i].clip_min)) {
 563                                 clip_context->move_to (i, tips[i].top);
 564                                 /* clip-indicating upper terminal line */
 565                                 clip_context->rel_line_to (0, min (clip_height, ceil(tips[i].spread + .5)));
 566                         } else {
 567                                 outline_context->move_to (i, tips[i].top);
 568                                 /* normal upper terminal dot */
 569                                 outline_context->rel_line_to (0, -1.0);
 570                         }
 571                 }
 572
 573                 wave_context->stroke ();
 574                 clip_context->stroke ();
 575                 outline_context->stroke ();
 576
 577         } else {
 578                 const int height_zero = floor( _height * .5);
 579
 580                 for (int i = 0; i < n_peaks; ++i) {
 581
 582                         /* waveform line */
 583
 584                         if (tips[i].spread >= 2.0) {
 585                                 wave_context->move_to (i, tips[i].top);
 586                                 wave_context->line_to (i, tips[i].bot);
 587                         }
 588
 589                         /* draw square waves and other discontiguous points clearly */
 590                         if (i > 0) {
 591                                 if (tips[i-1].top + 2 < tips[i].top) {
 592                                         wave_context->move_to (i-1, tips[i-1].top);
 593                                         wave_context->line_to (i-1, (tips[i].bot + tips[i-1].top)/2);
 594                                         wave_context->move_to (i, (tips[i].bot + tips[i-1].top)/2);
 595                                         wave_context->line_to (i, tips[i].top);
 596                                 } else if (tips[i-1].bot > tips[i].bot + 2) {
 597                                         wave_context->move_to (i-1, tips[i-1].bot);
 598                                         wave_context->line_to (i-1, (tips[i].top + tips[i-1].bot)/2);
 599                                         wave_context->move_to (i, (tips[i].top + tips[i-1].bot)/2);
 600                                         wave_context->line_to (i, tips[i].bot);
 601                                 }
 602                         }
 603
 604                         /* zero line, show only if there is enough spread
 605                         or the waveform line does not cross zero line */
 606
 607                         if (show_zero_line() && ((tips[i].spread >= 5.0) || (tips[i].top > height_zero ) || (tips[i].bot < height_zero)) ) {
 608                                 zero_context->move_to (i, height_zero);
 609                                 zero_context->rel_line_to (1.0, 0);
 610                         }
 611
 612                         if (tips[i].spread > 1.0) {
 613                                 bool clipped = false;
 614                                 /* outline/clip indicators */
 615                                 if (_global_show_waveform_clipping && tips[i].clip_max) {
 616                                         clip_context->move_to (i, tips[i].top);
 617                                         /* clip-indicating upper terminal line */
 618                                         clip_context->rel_line_to (0, min (clip_height, ceil(tips[i].spread + 0.5)));
 619                                         clipped = true;
 620                                 }
 621
 622                                 if (_global_show_waveform_clipping && tips[i].clip_min) {
 623                                         clip_context->move_to (i, tips[i].bot);
 624                                         /* clip-indicating lower terminal line */
 625                                         clip_context->rel_line_to (0, - min (clip_height, ceil(tips[i].spread + 0.5)));
 626                                         clipped = true;
 627                                 }
 628
 629                                 if (!clipped && tips[i].spread > 2.0) {
 630                                         /* only draw the outline if the spread
 631                                            implies 3 or more pixels (so that we see 1
 632                                            white pixel in the middle).
 633                                         */
 634                                         outline_context->move_to (i, tips[i].bot);
 635                                         /* normal lower terminal dot; line moves up */
 636                                         outline_context->rel_line_to (0, -1.0);
 637
 638                                         outline_context->move_to (i, tips[i].top);
 639                                         /* normal upper terminal dot, line moves down */
 640                                         outline_context->rel_line_to (0, 1.0);
 641                                 }
 642                         } else {
 643                                 bool clipped = false;
 644                                 /* outline/clip indicator */
 645                                 if (_global_show_waveform_clipping && (tips[i].clip_max || tips[i].clip_min)) {
 646                                         clip_context->move_to (i, tips[i].top);
 647                                         /* clip-indicating upper / lower terminal line */
 648                                         clip_context->rel_line_to (0, 1.0);
 649                                         clipped = true;
 650                                 }
 651
 652                                 if (!clipped) {
 653                                         /* special case where only 1 pixel of
 654                                          * the waveform line is drawn (and
 655                                          * nothing else).
 656                                          *
 657                                          * we draw a 1px "line", pretending
 658                                          * that the span is 1.0 (whether it is
 659                                          * zero or 1.0)
 660                                          */
 661                                         wave_context->move_to (i, tips[i].top);
 662                                         wave_context->rel_line_to (0, 1.0);
 663                                 }
 664                         }
 665                 }
 666
 667                 wave_context->stroke ();
 668                 outline_context->stroke ();
 669                 clip_context->stroke ();
 670                 zero_context->stroke ();
 671         }
 672
 673         if (req->should_stop()) {
 674                 return;
 675         }
 676
 677         Cairo::RefPtr<Cairo::Context> context = Cairo::Context::create (image);
 678
 679         /* Here we set a source colour and use the various components as a mask. */
 680
 681         if (gradient_depth() != 0.0) {
 682
 683                 Cairo::RefPtr<Cairo::LinearGradient> gradient (Cairo::LinearGradient::create (0, 0, 0, _height));
 684
 685                 double stops[3];
 686
 687                 double r, g, b, a;
 688
 689                 if (_shape == Rectified) {
 690                         stops[0] = 0.1;
 691                         stops[1] = 0.3;
 692                         stops[2] = 0.9;
 693                 } else {
 694                         stops[0] = 0.1;
 695                         stops[1] = 0.5;
 696                         stops[2] = 0.9;
 697                 }
 698
 699                 color_to_rgba (_fill_color, r, g, b, a);
 700                 gradient->add_color_stop_rgba (stops[1], r, g, b, a);
 701                 /* generate a new color for the middle of the gradient */
 702                 double h, s, v;
 703                 color_to_hsv (_fill_color, h, s, v);
 704                 /* change v towards white */
 705                 v *= 1.0 - gradient_depth();
 706                 Color center = hsva_to_color (h, s, v, a);
 707                 color_to_rgba (center, r, g, b, a);
 708
 709                 gradient->add_color_stop_rgba (stops[0], r, g, b, a);
 710                 gradient->add_color_stop_rgba (stops[2], r, g, b, a);
 711
 712                 context->set_source (gradient);
 713         } else {
 714                 set_source_rgba (context, _fill_color);
 715         }
 716
 717         if (req->should_stop()) {
 718                 return;
 719         }
 720
 721         context->mask (images.wave, 0, 0);
 722         context->fill ();
 723
 724         set_source_rgba (context, _outline_color);
 725         context->mask (images.outline, 0, 0);
 726         context->fill ();
 727
 728         set_source_rgba (context, _clip_color);
 729         context->mask (images.clip, 0, 0);
 730         context->fill ();
 731
 732         set_source_rgba (context, _zero_color);
 733         context->mask (images.zero, 0, 0);
 734         context->fill ();
 735 }
 736
 737 boost::shared_ptr<WaveViewCache::Entry>
 738 WaveView::cache_request_result (boost::shared_ptr<WaveViewThreadRequest> req) const
 739 {
 740         boost::shared_ptr<WaveViewCache::Entry> ret (new WaveViewCache::Entry (req->channel,
 741                                                                                req->height,
 742                                                                                req->amplitude,
 743                                                                                req->fill_color,
 744                                                                                req->samples_per_pixel,
 745                                                                                req->start,
 746                                                                                req->end,
 747                                                                                req->image));
 748         images->add (_region->audio_source (_channel), ret);
 749
 750         /* consolidate cache first (removes fully-contained
 751          * duplicate images)
 752          */
 753
 754         images->consolidate_image_cache (_region->audio_source (_channel),
 755                                          req->channel, req->height, req->amplitude,
 756                                          req->fill_color, req->samples_per_pixel);
 757
 758         return ret;
 759 }
 760
 761 boost::shared_ptr<WaveViewCache::Entry>
 762 WaveView::get_image (framepos_t start, framepos_t end, bool& full_image) const
 763 {
 764         boost::shared_ptr<WaveViewCache::Entry> ret;
 765
 766         full_image = true;
 767
 768         /* this is called from a ::render() call, when we need an image to
 769            draw with.
 770         */
 771
 772         DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 needs image from %2 .. %3\n", name, start, end));
 773
 774
 775         {
 776                 Glib::Threads::Mutex::Lock lmq (request_queue_lock);
 777
 778                 /* if there's a draw request outstanding, check to see if we
 779                  * have an image there. if so, use it (and put it in the cache
 780                  * while we're here.
 781                  */
 782
 783                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 CR %2 stop? %3 image %4\n", this, current_request,
 784                                                               (current_request ? current_request->should_stop() : false),
 785                                                               (current_request ? current_request->image : 0)));
 786
 787                 if (current_request && !current_request->should_stop() && current_request->image) {
 788
 789                         /* put the image into the cache so that other
 790                          * WaveViews can use it if it is useful
 791                          */
 792
 793                         if (current_request->start <= start && current_request->end >= end) {
 794
 795                                 ret.reset (new WaveViewCache::Entry (current_request->channel,
 796                                                                      current_request->height,
 797                                                                      current_request->amplitude,
 798                                                                      current_request->fill_color,
 799                                                                      current_request->samples_per_pixel,
 800                                                                      current_request->start,
 801                                                                      current_request->end,
 802                                                                      current_request->image));
 803
 804                                 cache_request_result (current_request);
 805                                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1: got image from completed request, spans %2..%3\n",
 806                                                                               name, current_request->start, current_request->end));
 807                         }
 808
 809                         /* drop our handle on the current request */
 810                         current_request.reset ();
 811                 }
 812         }
 813
 814         if (!ret) {
 815
 816                 /* no current image draw request, so look in the cache */
 817
 818                 ret = get_image_from_cache (start, end, full_image);
 819                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1: lookup from cache gave %2 (full %3)\n",
 820                                                               name, ret, full_image));
 821
 822         }
 823
 824
 825
 826         if (!ret || !full_image) {
 827
 828                 if ((rendered && get_image_in_thread) || always_get_image_in_thread) {
 829
 830                         DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1: generating image in caller thread\n", name));
 831
 832                         boost::shared_ptr<WaveViewThreadRequest> req (new WaveViewThreadRequest);
 833
 834                         req->type = WaveViewThreadRequest::Draw;
 835                         req->start = start;
 836                         req->end = end;
 837                         req->samples_per_pixel = _samples_per_pixel;
 838                         req->region = _region; /* weak ptr, to avoid storing a reference in the request queue */
 839                         req->channel = _channel;
 840                         req->height = _height;
 841                         req->fill_color = _fill_color;
 842                         req->amplitude = _region_amplitude * _amplitude_above_axis;
 843                         req->width = desired_image_width ();
 844
 845                         /* draw image in this (the GUI thread) */
 846
 847                         generate_image (req, false);
 848
 849                         /* cache the result */
 850
 851                         ret = cache_request_result (req);
 852
 853                         /* reset this so that future missing images are
 854                          * generated in a a worker thread.
 855                          */
 856
 857                         get_image_in_thread = false;
 858
 859                 } else {
 860                         queue_get_image (_region, start, end);
 861                 }
 862         }
 863
 864         if (ret) {
 865                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 got an image from %2 .. %3 (full ? %4)\n", name, ret->start, ret->end, full_image));
 866         } else {
 867                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 no useful image available\n", name));
 868         }
 869
 870         return ret;
 871 }
 872
 873 boost::shared_ptr<WaveViewCache::Entry>
 874 WaveView::get_image_from_cache (framepos_t start, framepos_t end, bool& full) const
 875 {
 876         if (!images) {
 877                 return boost::shared_ptr<WaveViewCache::Entry>();
 878         }
 879
 880         return images->lookup_image (_region->audio_source (_channel), start, end, _channel,
 881                                      _height, _region_amplitude * _amplitude_above_axis, _fill_color, _samples_per_pixel, full);
 882 }
 883
 884 framecnt_t
 885 WaveView::desired_image_width () const
 886 {
 887         /* compute how wide the image should be, in samples.
 888          *
 889          * We want at least 1 canvas width's worth, but if that
 890          * represents less than 1/10th of a second, use 1/10th of
 891          * a second instead.
 892          */
 893
 894         framecnt_t canvas_width_samples = _canvas->visible_area().width() * _samples_per_pixel;
 895         const framecnt_t one_tenth_of_second = _region->session().frame_rate() / 10;
 896
 897         if (canvas_width_samples > one_tenth_of_second) {
 898                 return  canvas_width_samples;
 899         }
 900
 901         return one_tenth_of_second;
 902 }
 903
 904 void
 905 WaveView::queue_get_image (boost::shared_ptr<const ARDOUR::Region> region, framepos_t start, framepos_t end) const
 906 {
 907         boost::shared_ptr<WaveViewThreadRequest> req (new WaveViewThreadRequest);
 908
 909         req->type = WaveViewThreadRequest::Draw;
 910         req->start = start;
 911         req->end = end;
 912         req->samples_per_pixel = _samples_per_pixel;
 913         req->region = _region; /* weak ptr, to avoid storing a reference in the request queue */
 914         req->channel = _channel;
 915         req->height = _height;
 916         req->fill_color = _fill_color;
 917         req->amplitude = _region_amplitude * _amplitude_above_axis;
 918         req->width = desired_image_width ();
 919
 920         if (current_request) {
 921                 /* this will stop rendering in progress (which might otherwise
 922                    be long lived) for any current request.
 923                 */
 924                 current_request->cancel ();
 925         }
 926
 927         start_drawing_thread ();
 928
 929         /* swap requests (protected by lock) */
 930
 931         {
 932                 Glib::Threads::Mutex::Lock lm (request_queue_lock);
 933                 current_request = req;
 934
 935                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 now has current request %2\n", this, req));
 936
 937                 if (request_queue.insert (this).second) {
 938                         /* this waveview was not already in the request queue, make sure we wake
 939                            the rendering thread in case it is asleep.
 940                         */
 941                         request_cond.signal ();
 942                 }
 943         }
 944 }
 945
 946 void
 947 WaveView::generate_image (boost::shared_ptr<WaveViewThreadRequest> req, bool in_render_thread) const
 948 {
 949         if (!req->should_stop()) {
 950
 951                 /* sample position is canonical here, and we want to generate
 952                  * an image that spans about 3x the canvas width. We get to that
 953                  * width by using an image sample count of the screen width added
 954                  * on each side of the desired image center.
 955                  */
 956
 957                 const framepos_t center = req->start + ((req->end - req->start) / 2);
 958                 const framecnt_t image_samples = req->width;
 959
 960                 /* we can request data from anywhere in the Source, between 0 and its length
 961                  */
 962
 963                 framepos_t sample_start = max (_region_start, (center - image_samples));
 964                 framepos_t sample_end = min (center + image_samples, region_end());
 965                 const int n_peaks = llrintf ((sample_end - sample_start)/ (req->samples_per_pixel));
 966
 967                 boost::scoped_array<ARDOUR::PeakData> peaks (new PeakData[n_peaks]);
 968
 969                 /* Note that Region::read_peaks() takes a start position based on an
 970                    offset into the Region's **SOURCE**, rather than an offset into
 971                    the Region itself.
 972                 */
 973
 974                 framecnt_t peaks_read = _region->read_peaks (peaks.get(), n_peaks,
 975                                                              sample_start, sample_end - sample_start,
 976                                                              req->channel,
 977                                                              req->samples_per_pixel);
 978
 979                 req->image = Cairo::ImageSurface::create (Cairo::FORMAT_ARGB32, n_peaks, req->height);
 980                 /* make sure we record the sample positions that were actually used */
 981                 req->start = sample_start;
 982                 req->end = sample_end;
 983
 984                 if (peaks_read > 0) {
 985
 986                         if (_amplitude_above_axis != 1.0) {
 987                                 for (framecnt_t i = 0; i < n_peaks; ++i) {
 988                                         peaks[i].max *= _amplitude_above_axis;
 989                                         peaks[i].min *= _amplitude_above_axis;
 990                                 }
 991                         }
 992
 993                         draw_image (req->image, peaks.get(), n_peaks, req);
 994                 } else {
 995                         draw_absent_image (req->image, peaks.get(), n_peaks);
 996                 }
 997         }
 998
 999         if (in_render_thread && !req->should_stop()) {
1000                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("done with request for %1 at %2 CR %3 req %4 range %5 .. %6\n", this, g_get_monotonic_time(), current_request, req, req->start, req->end));
1001                 const_cast<WaveView*>(this)->ImageReady (); /* emit signal */
1002         }
1003
1004         return;
1005 }
1006
1007 /** Given a waveform that starts at window x-coordinate @param wave_origin
1008  * and the first pixel that we will actually draw @param draw_start, return
1009  * the offset into an image of the entire waveform that we will need to use.
1010  *
1011  * Note: most of our cached images are NOT of the entire waveform, this is just
1012  * computationally useful when determining which the sample range span for
1013  * the image we need.
1014  */
1015 static inline double
1016 window_to_image (double wave_origin, double image_start)
1017 {
1018         return image_start - wave_origin;
1019 }
1020
1021 void
1022 WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
1023 {
1024         assert (_samples_per_pixel != 0);
1025
1026         if (!_region) {
1027                 return;
1028         }
1029
1030         DEBUG_TRACE (DEBUG::WaveView, string_compose ("render %1 at %2\n", this, g_get_monotonic_time()));
1031
1032         /* a WaveView is intimately connected to an AudioRegion. It will
1033          * display the waveform within the region, anywhere from the start of
1034          * the region to its end.
1035          *
1036          * the area we've been aked to render may overlap with area covered
1037          * by the region in any of the normal ways:
1038          *
1039          *  - it may begin and end within the area covered by the region
1040          *  - it may start before and end after the area covered by region
1041          *  - it may start before and end within the area covered by the region
1042          *  - it may start within and end after the area covered by the region
1043          *  - it may be precisely coincident with the area covered by region.
1044          *
1045          * So let's start by determining the area covered by the region, in
1046          * window coordinates. It begins at zero (in item coordinates for this
1047          * waveview, and extends to region_length() / _samples_per_pixel.
1048          */
1049
1050         Rect self = item_to_window (Rect (0.0, 0.0, region_length() / _samples_per_pixel, _height));
1051
1052         // cerr << name << " RENDER " << area << " self = " << self << endl;
1053
1054         /* Now lets get the intersection with the area we've been asked to draw */
1055
1056         boost::optional<Rect> d = self.intersection (area);
1057
1058         if (!d) {
1059                 return;
1060         }
1061
1062         Rect draw = d.get();
1063
1064         /* "draw" is now a rectangle that defines the rectangle we need to
1065          * update/render the waveview into, in window coordinate space.
1066          */
1067
1068         /* window coordinates - pixels where x=0 is the left edge of the canvas
1069          * window. We round down in case we were asked to
1070          * draw "between" pixels at the start and/or end.
1071          */
1072
1073         double draw_start = floor (draw.x0);
1074         const double draw_end = floor (draw.x1);
1075
1076         // cerr << "Need to draw " << draw_start << " .. " << draw_end << " vs. " << area << " and self = " << self << endl;
1077
1078         /* image coordnates: pixels where x=0 is the start of this waveview,
1079          * wherever it may be positioned. thus image_start=N means "an image
1080          * that begins N pixels after the start of region that this waveview is
1081          * representing.
1082          */
1083
1084         const framepos_t image_start = window_to_image (self.x0, draw_start);
1085         const framepos_t image_end = window_to_image (self.x0, draw_end);
1086
1087         // cerr << "Image/WV space: " << image_start << " .. " << image_end << endl;
1088
1089         /* sample coordinates - note, these are not subject to rounding error
1090          *
1091          * "sample_start = N" means "the first sample we need to represent is N
1092          * samples after the first sample of the region"
1093          */
1094
1095         framepos_t sample_start = _region_start + (image_start * _samples_per_pixel);
1096         framepos_t sample_end   = _region_start + (image_end * _samples_per_pixel);
1097
1098         // cerr << "Sample space: " << sample_start << " .. " << sample_end << " @ " << _samples_per_pixel << " rs = " << _region_start << endl;
1099
1100         /* sample_start and sample_end are bounded by the region
1101          * limits. sample_start, because of the was just computed, must already
1102          * be greater than or equal to the _region_start value.
1103          */
1104
1105         sample_end = min (region_end(), sample_end);
1106
1107         // cerr << debug_name() << " will need image spanning " << sample_start << " .. " << sample_end << " region spans " << _region_start << " .. " << region_end() << endl;
1108
1109         double image_origin_in_self_coordinates;
1110         boost::shared_ptr<WaveViewCache::Entry> image_to_draw;
1111
1112         if (_current_image) {
1113
1114                 /* check it covers the right sample range */
1115
1116                 if (_current_image->start > sample_start || _current_image->end < sample_end) {
1117                         /* doesn't cover the area we need ... reset */
1118                         _current_image.reset ();
1119                 } else {
1120                         /* timestamp our continuing use of this image/cache entry */
1121                         images->use (_region->audio_source (_channel), _current_image);
1122                         image_to_draw = _current_image;
1123                 }
1124         }
1125
1126         if (!image_to_draw) {
1127
1128                 /* look it up */
1129
1130                 bool full_image;
1131                 image_to_draw = get_image (sample_start, sample_end, full_image);
1132
1133                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 image to draw = %2 (full? %3)\n", name, image_to_draw, full_image));
1134
1135                 if (!image_to_draw) {
1136                         /* image not currently available. A redraw will be scheduled
1137                            when it is ready.
1138                         */
1139                         return;
1140                 }
1141
1142                 if (full_image) {
1143                         /* found an image that covers our entire sample range,
1144                          * so keep a reference to it.
1145                          */
1146                         _current_image = image_to_draw;
1147                 }
1148         }
1149
1150         /* compute the first pixel of the image that should be used when we
1151          * render the specified range.
1152          */
1153
1154         image_origin_in_self_coordinates = (image_to_draw->start - _region_start) / _samples_per_pixel;
1155
1156         if (_start_shift && (sample_start == _region_start) && (self.x0 == draw.x0)) {
1157                 /* we are going to draw the first pixel for this region, but
1158                    we may not want this to overlap a border around the
1159                    waveform. If so, _start_shift will be set.
1160                 */
1161                 //cerr << name.substr (23) << " ss = " << sample_start << " rs = " << _region_start << " sf = " << _start_shift << " ds = " << draw_start << " self = " << self << " draw = " << draw << endl;
1162                 //draw_start += _start_shift;
1163                 //image_origin_in_self_coordinates += _start_shift;
1164         }
1165
1166         /* the image may only be a best-effort ... it may not span the entire
1167          * range requested, though it is guaranteed to cover the start. So
1168          * determine how many pixels we can actually draw.
1169          */
1170
1171         double draw_width;
1172
1173         if (image_to_draw != _current_image) {
1174
1175                 /* the image is guaranteed to start at or before
1176                  * draw_start. But if it starts before draw_start, that reduces
1177                  * the maximum available width we can render with.
1178                  *
1179                  * so .. clamp the draw width to the smaller of what we need to
1180                  * draw or the available width of the image.
1181                  */
1182
1183                 draw_width = min ((double) image_to_draw->image->get_width() - (draw_start - image_to_draw->start),
1184                                   (draw_end - draw_start));
1185
1186
1187                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 draw just %2 of %3 (iwidth %4 off %5 img @ %6 rs @ %7)\n", name, draw_width, (draw_end - draw_start),
1188                                                               image_to_draw->image->get_width(), image_origin_in_self_coordinates,
1189                                                               image_to_draw->start, _region_start));
1190         } else {
1191                 draw_width = draw_end - draw_start;
1192                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("use current image, span entire render width %1..%2\n", draw_start, draw_end));
1193         }
1194
1195         context->rectangle (draw_start, draw.y0, draw_width, draw.height());
1196
1197         /* round image origin position to an exact pixel in device space to
1198          * avoid blurring
1199          */
1200
1201         double x  = self.x0 + image_origin_in_self_coordinates;
1202         double y  = self.y0;
1203         context->user_to_device (x, y);
1204         x = round (x);
1205         y = round (y);
1206         context->device_to_user (x, y);
1207
1208         /* the coordinates specify where in "user coordinates" (i.e. what we
1209          * generally call "canvas coordinates" in this code) the image origin
1210          * will appear. So specifying (10,10) will put the upper left corner of
1211          * the image at (10,10) in user space.
1212          */
1213
1214         context->set_source (image_to_draw->image, x, y);
1215         context->fill ();
1216
1217         /* image obtained, some of it painted to display: we are rendered.
1218            Future calls to get_image_in_thread are now meaningful.
1219         */
1220
1221         rendered = true;
1222 }
1223
1224 void
1225 WaveView::compute_bounding_box () const
1226 {
1227         if (_region) {
1228                 _bounding_box = Rect (0.0, 0.0, region_length() / _samples_per_pixel, _height);
1229         } else {
1230                 _bounding_box = boost::optional<Rect> ();
1231         }
1232
1233         _bounding_box_dirty = false;
1234 }
1235
1236 void
1237 WaveView::set_height (Distance height)
1238 {
1239         if (height != _height) {
1240                 begin_change ();
1241
1242                 invalidate_image_cache ();
1243                 _height = height;
1244                 get_image_in_thread = true;
1245
1246                 _bounding_box_dirty = true;
1247                 end_change ();
1248         }
1249 }
1250
1251 void
1252 WaveView::set_channel (int channel)
1253 {
1254         if (channel != _channel) {
1255                 begin_change ();
1256
1257                 invalidate_image_cache ();
1258                 _channel = channel;
1259
1260                 _bounding_box_dirty = true;
1261                 end_change ();
1262         }
1263 }
1264
1265 void
1266 WaveView::set_logscaled (bool yn)
1267 {
1268         if (_logscaled != yn) {
1269                 begin_visual_change ();
1270                 invalidate_image_cache ();
1271                 _logscaled = yn;
1272                 end_visual_change ();
1273         }
1274 }
1275
1276 void
1277 WaveView::gain_changed ()
1278 {
1279         begin_visual_change ();
1280         invalidate_image_cache ();
1281         _region_amplitude = _region->scale_amplitude ();
1282         get_image_in_thread = true;
1283         end_visual_change ();
1284 }
1285
1286 void
1287 WaveView::set_zero_color (Color c)
1288 {
1289         if (_zero_color != c) {
1290                 begin_visual_change ();
1291                 invalidate_image_cache ();
1292                 _zero_color = c;
1293                 end_visual_change ();
1294         }
1295 }
1296
1297 void
1298 WaveView::set_clip_color (Color c)
1299 {
1300         if (_clip_color != c) {
1301                 begin_visual_change ();
1302                 invalidate_image_cache ();
1303                 _clip_color = c;
1304                 end_visual_change ();
1305         }
1306 }
1307
1308 void
1309 WaveView::set_show_zero_line (bool yn)
1310 {
1311         if (_show_zero != yn) {
1312                 begin_visual_change ();
1313                 invalidate_image_cache ();
1314                 _show_zero = yn;
1315                 end_visual_change ();
1316         }
1317 }
1318
1319 void
1320 WaveView::set_shape (Shape s)
1321 {
1322         if (_shape != s) {
1323                 begin_visual_change ();
1324                 invalidate_image_cache ();
1325                 _shape = s;
1326                 end_visual_change ();
1327         }
1328 }
1329
1330 void
1331 WaveView::set_amplitude_above_axis (double a)
1332 {
1333         if (fabs (_amplitude_above_axis - a) > 0.01) {
1334                 begin_visual_change ();
1335                 invalidate_image_cache ();
1336                 _amplitude_above_axis = a;
1337                 get_image_in_thread = true;
1338                 end_visual_change ();
1339         }
1340 }
1341
1342 void
1343 WaveView::set_global_shape (Shape s)
1344 {
1345         if (_global_shape != s) {
1346                 _global_shape = s;
1347                 VisualPropertiesChanged (); /* EMIT SIGNAL */
1348         }
1349 }
1350
1351 void
1352 WaveView::set_global_logscaled (bool yn)
1353 {
1354         if (_global_logscaled != yn) {
1355                 _global_logscaled = yn;
1356                 VisualPropertiesChanged (); /* EMIT SIGNAL */
1357         }
1358 }
1359
1360 framecnt_t
1361 WaveView::region_length() const
1362 {
1363         return _region->length() - (_region_start - _region->start());
1364 }
1365
1366 framepos_t
1367 WaveView::region_end() const
1368 {
1369         return _region_start + region_length();
1370 }
1371
1372 void
1373 WaveView::set_region_start (frameoffset_t start)
1374 {
1375         if (!_region) {
1376                 return;
1377         }
1378
1379         if (_region_start == start) {
1380                 return;
1381         }
1382
1383         begin_change ();
1384         _region_start = start;
1385         _bounding_box_dirty = true;
1386         end_change ();
1387 }
1388
1389 void
1390 WaveView::region_resized ()
1391 {
1392         /* Called when the region start or end (thus length) has changed.
1393         */
1394
1395         if (!_region) {
1396                 return;
1397         }
1398
1399         begin_change ();
1400         _region_start = _region->start();
1401         _bounding_box_dirty = true;
1402         end_change ();
1403 }
1404
1405 void
1406 WaveView::set_global_gradient_depth (double depth)
1407 {
1408         if (_global_gradient_depth != depth) {
1409                 _global_gradient_depth = depth;
1410                 VisualPropertiesChanged (); /* EMIT SIGNAL */
1411         }
1412 }
1413
1414 void
1415 WaveView::set_global_show_waveform_clipping (bool yn)
1416 {
1417         if (_global_show_waveform_clipping != yn) {
1418                 _global_show_waveform_clipping = yn;
1419                 ClipLevelChanged ();
1420         }
1421 }
1422
1423 void
1424 WaveView::set_start_shift (double pixels)
1425 {
1426         if (pixels < 0) {
1427                 return;
1428         }
1429
1430         begin_visual_change ();
1431         _start_shift = pixels;
1432         end_visual_change ();
1433 }
1434
1435 void
1436 WaveView::cancel_my_render_request () const
1437 {
1438         if (!images) {
1439                 return;
1440         }
1441
1442         /* try to stop any current rendering of the request, or prevent it from
1443          * ever starting up.
1444          */
1445
1446         if (current_request) {
1447                 current_request->cancel ();
1448         }
1449
1450         Glib::Threads::Mutex::Lock lm (request_queue_lock);
1451
1452         /* now remove it from the queue and reset our request pointer so that
1453            have no outstanding request (that we know about)
1454         */
1455
1456         request_queue.erase (this);
1457         current_request.reset ();
1458         DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 now has no request %2\n", this));
1459
1460 }
1461
1462 void
1463 WaveView::set_image_cache_size (uint64_t sz)
1464 {
1465         if (!images) {
1466                 images = new WaveViewCache;
1467         }
1468
1469         images->set_image_cache_threshold (sz);
1470 }
1471
1472 /*-------------------------------------------------*/
1473
1474 void
1475 WaveView::start_drawing_thread ()
1476 {
1477         if (!_drawing_thread) {
1478                 _drawing_thread = Glib::Threads::Thread::create (sigc::ptr_fun (WaveView::drawing_thread));
1479         }
1480 }
1481
1482 void
1483 WaveView::stop_drawing_thread ()
1484 {
1485         if (_drawing_thread) {
1486                 Glib::Threads::Mutex::Lock lm (request_queue_lock);
1487                 g_atomic_int_set (&drawing_thread_should_quit, 1);
1488                 request_cond.signal ();
1489         }
1490 }
1491
1492 void
1493 WaveView::drawing_thread ()
1494 {
1495         using namespace Glib::Threads;
1496
1497         WaveView const * requestor;
1498         Mutex::Lock lm (request_queue_lock);
1499         bool run = true;
1500
1501         while (run) {
1502
1503                 /* remember that we hold the lock at this point, no matter what */
1504
1505                 if (g_atomic_int_get (&drawing_thread_should_quit)) {
1506                         break;
1507                 }
1508
1509                 if (request_queue.empty()) {
1510                         request_cond.wait (request_queue_lock);
1511                 }
1512
1513                 /* remove the request from the queue (remember: the "request"
1514                  * is just a pointer to a WaveView object)
1515                  */
1516
1517                 requestor = *(request_queue.begin());
1518                 request_queue.erase (request_queue.begin());
1519
1520                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("start request for %1 at %2\n", requestor, g_get_monotonic_time()));
1521
1522                 boost::shared_ptr<WaveViewThreadRequest> req = requestor->current_request;
1523
1524                 if (!req) {
1525                         continue;
1526                 }
1527
1528                 /* Generate an image. Unlock the request queue lock
1529                  * while we do this, so that other things can happen
1530                  * as we do rendering.
1531                  */
1532
1533                 request_queue_lock.unlock (); /* some RAII would be good here */
1534
1535                 try {
1536                         requestor->generate_image (req, true);
1537                 } catch (...) {
1538                         req->image.clear(); /* just in case it was set before the exception, whatever it was */
1539                 }
1540
1541                 request_queue_lock.lock ();
1542
1543                 req.reset (); /* drop/delete request as appropriate */
1544         }
1545
1546         /* thread is vanishing */
1547         _drawing_thread = 0;
1548 }
1549
1550 /*-------------------------------------------------*/
1551
1552 WaveViewCache::WaveViewCache ()
1553         : image_cache_size (0)
1554         , _image_cache_threshold (100 * 1048576) /* bytes */
1555 {
1556 }
1557
1558 WaveViewCache::~WaveViewCache ()
1559 {
1560 }
1561
1562
1563 boost::shared_ptr<WaveViewCache::Entry>
1564 WaveViewCache::lookup_image (boost::shared_ptr<ARDOUR::AudioSource> src,
1565                              framepos_t start, framepos_t end,
1566                              int channel,
1567                              Coord height,
1568                              float amplitude,
1569                              Color fill_color,
1570                              double samples_per_pixel,
1571                              bool& full_coverage)
1572 {
1573         ImageCache::iterator x;
1574
1575         if ((x = cache_map.find (src)) == cache_map.end ()) {
1576                 /* nothing in the cache for this audio source at all */
1577                 return boost::shared_ptr<WaveViewCache::Entry> ();
1578         }
1579
1580         CacheLine& caches = x->second;
1581         boost::shared_ptr<Entry> best_partial;
1582         framecnt_t max_coverage = 0;
1583
1584         /* Find a suitable ImageSurface, if it exists.
1585         */
1586
1587         for (CacheLine::iterator c = caches.begin(); c != caches.end(); ++c) {
1588
1589                 boost::shared_ptr<Entry> e (*c);
1590
1591                 if (channel != e->channel
1592                     || height != e->height
1593                     || amplitude != e->amplitude
1594                     || samples_per_pixel != e->samples_per_pixel
1595                     || fill_color != e->fill_color) {
1596                         continue;
1597                 }
1598
1599                 switch (Evoral::coverage (start, end, e->start, e->end)) {
1600                 case Evoral::OverlapExternal:  /* required range is inside image range */
1601                         DEBUG_TRACE (DEBUG::WaveView, string_compose ("found image spanning %1..%2 covers %3..%4\n",
1602                                                                       e->start, e->end, start, end));
1603                         use (src, e);
1604                         full_coverage = true;
1605                         return e;
1606
1607                 case Evoral::OverlapStart: /* required range start is covered by image range */
1608                         if ((e->end - start) > max_coverage) {
1609                                 best_partial = e;
1610                                 max_coverage = e->end - start;
1611                         }
1612                         break;
1613
1614                 case Evoral::OverlapNone:
1615                 case Evoral::OverlapEnd:
1616                 case Evoral::OverlapInternal:
1617                         break;
1618                 }
1619         }
1620
1621         if (best_partial) {
1622                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("found PARTIAL image spanning %1..%2 partially covers %3..%4\n",
1623                                                               best_partial->start, best_partial->end, start, end));
1624                 use (src, best_partial);
1625                 full_coverage = false;
1626                 return best_partial;
1627         }
1628
1629         return boost::shared_ptr<Entry> ();
1630 }
1631
1632 void
1633 WaveViewCache::consolidate_image_cache (boost::shared_ptr<ARDOUR::AudioSource> src,
1634                                         int channel,
1635                                         Coord height,
1636                                         float amplitude,
1637                                         Color fill_color,
1638                                         double samples_per_pixel)
1639 {
1640         list <uint32_t> deletion_list;
1641         uint32_t other_entries = 0;
1642         ImageCache::iterator x;
1643
1644         /* MUST BE CALLED FROM (SINGLE) GUI THREAD */
1645
1646         if ((x = cache_map.find (src)) == cache_map.end ()) {
1647                 return;
1648         }
1649
1650         CacheLine& caches  = x->second;
1651
1652         for (CacheLine::iterator c1 = caches.begin(); c1 != caches.end(); ) {
1653
1654                 CacheLine::iterator nxt = c1;
1655                 ++nxt;
1656
1657                 boost::shared_ptr<Entry> e1 (*c1);
1658
1659                 if (channel != e1->channel
1660                     || height != e1->height
1661                     || amplitude != e1->amplitude
1662                     || samples_per_pixel != e1->samples_per_pixel
1663                     || fill_color != e1->fill_color) {
1664
1665                         /* doesn't match current properties, ignore and move on
1666                          * to the next one.
1667                          */
1668
1669                         other_entries++;
1670                         c1 = nxt;
1671                         continue;
1672                 }
1673
1674                 /* c1 now points to a cached image entry that matches current
1675                  * properties. Check all subsequent cached imaged entries to
1676                  * see if there are others that also match but represent
1677                  * subsets of the range covered by this one.
1678                  */
1679
1680                 for (CacheLine::iterator c2 = c1; c2 != caches.end(); ) {
1681
1682                         CacheLine::iterator nxt2 = c2;
1683                         ++nxt2;
1684
1685                         boost::shared_ptr<Entry> e2 (*c2);
1686
1687                         if (e1 == e2 || channel != e2->channel
1688                             || height != e2->height
1689                             || amplitude != e2->amplitude
1690                             || samples_per_pixel != e2->samples_per_pixel
1691                             || fill_color != e2->fill_color) {
1692
1693                                 /* properties do not match, ignore for the
1694                                  * purposes of consolidation.
1695                                  */
1696                                 c2 = nxt2;
1697                                 continue;
1698                         }
1699
1700                         if (e2->start >= e1->start && e2->end <= e1->end) {
1701                                 /* c2 is fully contained by c1, so delete it */
1702                                 caches.erase (c2);
1703
1704                                 /* and re-start the whole iteration */
1705                                 nxt = caches.begin ();
1706                                 break;
1707                         }
1708
1709                         c2 = nxt2;
1710                 }
1711
1712                 c1 = nxt;
1713         }
1714 }
1715
1716 void
1717 WaveViewCache::use (boost::shared_ptr<ARDOUR::AudioSource> src, boost::shared_ptr<Entry> ce)
1718 {
1719         ce->timestamp = g_get_monotonic_time ();
1720 }
1721
1722 void
1723 WaveViewCache::add (boost::shared_ptr<ARDOUR::AudioSource> src, boost::shared_ptr<Entry> ce)
1724 {
1725         /* MUST BE CALLED FROM (SINGLE) GUI THREAD */
1726
1727         Cairo::RefPtr<Cairo::ImageSurface> img (ce->image);
1728
1729         image_cache_size += img->get_height() * img->get_width () * 4; /* 4 = bytes per FORMAT_ARGB32 pixel */
1730
1731         if (cache_full()) {
1732                 cache_flush ();
1733         }
1734
1735         ce->timestamp = g_get_monotonic_time ();
1736
1737         cache_map[src].push_back (ce);
1738 }
1739
1740 uint64_t
1741 WaveViewCache::compute_image_cache_size()
1742 {
1743         uint64_t total = 0;
1744         for (ImageCache::iterator s = cache_map.begin(); s != cache_map.end(); ++s) {
1745                 CacheLine& per_source_cache (s->second);
1746                 for (CacheLine::iterator c = per_source_cache.begin(); c != per_source_cache.end(); ++c) {
1747                         Cairo::RefPtr<Cairo::ImageSurface> img ((*c)->image);
1748                         total += img->get_height() * img->get_width() * 4; /* 4 = bytes per FORMAT_ARGB32 pixel */
1749                 }
1750         }
1751         return total;
1752 }
1753
1754 bool
1755 WaveViewCache::cache_full()
1756 {
1757         return image_cache_size > _image_cache_threshold;
1758 }
1759
1760 void
1761 WaveViewCache::cache_flush ()
1762 {
1763         /* Build a sortable list of all cache entries */
1764
1765         CacheList cache_list;
1766
1767         for (ImageCache::const_iterator cm = cache_map.begin(); cm != cache_map.end(); ++cm) {
1768                 for (CacheLine::const_iterator cl = cm->second.begin(); cl != cm->second.end(); ++cl) {
1769                         cache_list.push_back (make_pair (cm->first, *cl));
1770                 }
1771         }
1772
1773         /* sort list in LRU order */
1774         SortByTimestamp sorter;
1775         sort (cache_list.begin(), cache_list.end(), sorter);
1776
1777         while (image_cache_size > _image_cache_threshold && !cache_map.empty() && !cache_list.empty()) {
1778
1779                 ListEntry& le (cache_list.front());
1780
1781                 ImageCache::iterator x;
1782
1783                 if ((x = cache_map.find (le.first)) != cache_map.end ()) {
1784
1785                         CacheLine& cl  = x->second;
1786
1787                         for (CacheLine::iterator c = cl.begin(); c != cl.end(); ++c) {
1788
1789                                 if (*c == le.second) {
1790
1791                                         DEBUG_TRACE (DEBUG::WaveView, string_compose ("Removing cache line entry for %1\n", x->first->name()));
1792
1793                                         /* Remove this entry from this cache line */
1794                                         cl.erase (c);
1795
1796                                         if (cl.empty()) {
1797                                                 /* remove cache line from main cache: no more entries */
1798                                                 cache_map.erase (x);
1799                                         }
1800
1801                                         break;
1802                                 }
1803                         }
1804
1805                         Cairo::RefPtr<Cairo::ImageSurface> img (le.second->image);
1806                         uint64_t size = img->get_height() * img->get_width() * 4; /* 4 = bytes per FORMAT_ARGB32 pixel */
1807
1808                         if (image_cache_size > size) {
1809                                 image_cache_size -= size;
1810                         } else {
1811                                 image_cache_size = 0;
1812                         }
1813                         DEBUG_TRACE (DEBUG::WaveView, string_compose ("cache shrunk to %1\n", image_cache_size));
1814                 }
1815
1816                 /* Remove from the linear list, even if we didn't find it in
1817                  * the actual cache_mao
1818                  */
1819                 cache_list.erase (cache_list.begin());
1820         }
1821 }
1822
1823 void
1824 WaveViewCache::set_image_cache_threshold (uint64_t sz)
1825 {
1826         DEBUG_TRACE (DEBUG::WaveView, string_compose ("new image cache size \n", sz));
1827         _image_cache_threshold = sz;
1828         cache_flush ();
1829 }