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::Mutex WaveView::current_image_lock;
  69 Glib::Threads::Cond WaveView::request_cond;
  70 Glib::Threads::Thread* WaveView::_drawing_thread = 0;
  71 WaveView::DrawingRequestQueue WaveView::request_queue;
  72
  73 PBD::Signal0<void> WaveView::VisualPropertiesChanged;
  74 PBD::Signal0<void> WaveView::ClipLevelChanged;
  75
  76 WaveView::WaveView (Canvas* c, boost::shared_ptr<ARDOUR::AudioRegion> region)
  77         : Item (c)
  78         , _region (region)
  79         , _channel (0)
  80         , _samples_per_pixel (0)
  81         , _height (64)
  82         , _show_zero (false)
  83         , _zero_color (0xff0000ff)
  84         , _clip_color (0xff0000ff)
  85         , _logscaled (_global_logscaled)
  86         , _shape (_global_shape)
  87         , _gradient_depth (_global_gradient_depth)
  88         , _shape_independent (false)
  89         , _logscaled_independent (false)
  90         , _gradient_depth_independent (false)
  91         , _amplitude_above_axis (1.0)
  92         , _region_amplitude (region->scale_amplitude ())
  93         , _start_shift (0.0)
  94         , _region_start (region->start())
  95         , get_image_in_thread (false)
  96         , always_get_image_in_thread (false)
  97         , rendered (false)
  98 {
  99         if (!images) {
 100                 images = new WaveViewCache;
 101         }
 102
 103         VisualPropertiesChanged.connect_same_thread (invalidation_connection, boost::bind (&WaveView::handle_visual_property_change, this));
 104         ClipLevelChanged.connect_same_thread (invalidation_connection, boost::bind (&WaveView::handle_clip_level_change, this));
 105
 106         ImageReady.connect (image_ready_connection, invalidator (*this), boost::bind (&WaveView::image_ready, this), gui_context());
 107 }
 108
 109 WaveView::WaveView (Item* parent, boost::shared_ptr<ARDOUR::AudioRegion> region)
 110         : Item (parent)
 111         , _region (region)
 112         , _channel (0)
 113         , _samples_per_pixel (0)
 114         , _height (64)
 115         , _show_zero (false)
 116         , _zero_color (0xff0000ff)
 117         , _clip_color (0xff0000ff)
 118         , _logscaled (_global_logscaled)
 119         , _shape (_global_shape)
 120         , _gradient_depth (_global_gradient_depth)
 121         , _shape_independent (false)
 122         , _logscaled_independent (false)
 123         , _gradient_depth_independent (false)
 124         , _amplitude_above_axis (1.0)
 125         , _region_amplitude (region->scale_amplitude ())
 126         , _start_shift (0.0)
 127         , _region_start (region->start())
 128         , get_image_in_thread (false)
 129         , always_get_image_in_thread (false)
 130         , rendered (false)
 131 {
 132         if (!images) {
 133                 images = new WaveViewCache;
 134         }
 135
 136         VisualPropertiesChanged.connect_same_thread (invalidation_connection, boost::bind (&WaveView::handle_visual_property_change, this));
 137         ClipLevelChanged.connect_same_thread (invalidation_connection, boost::bind (&WaveView::handle_clip_level_change, this));
 138
 139         ImageReady.connect (image_ready_connection, invalidator (*this), boost::bind (&WaveView::image_ready, this), gui_context());
 140 }
 141
 142 WaveView::~WaveView ()
 143 {
 144         invalidate_image_cache ();
 145         if (images ) {
 146                 images->clear_cache ();
 147         }
 148 }
 149
 150 string
 151 WaveView::debug_name() const
 152 {
 153         return _region->name() + string (":") + PBD::to_string (_channel+1, std::dec);
 154 }
 155
 156 void
 157 WaveView::image_ready ()
 158 {
 159         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));
 160         redraw ();
 161 }
 162
 163 void
 164 WaveView::set_always_get_image_in_thread (bool yn)
 165 {
 166         always_get_image_in_thread = yn;
 167 }
 168
 169 void
 170 WaveView::handle_visual_property_change ()
 171 {
 172         bool changed = false;
 173
 174         if (!_shape_independent && (_shape != global_shape())) {
 175                 _shape = global_shape();
 176                 changed = true;
 177         }
 178
 179         if (!_logscaled_independent && (_logscaled != global_logscaled())) {
 180                 _logscaled = global_logscaled();
 181                 changed = true;
 182         }
 183
 184         if (!_gradient_depth_independent && (_gradient_depth != global_gradient_depth())) {
 185                 _gradient_depth = global_gradient_depth();
 186                 changed = true;
 187         }
 188
 189         if (changed) {
 190                 begin_visual_change ();
 191                 invalidate_image_cache ();
 192                 end_visual_change ();
 193         }
 194 }
 195
 196 void
 197 WaveView::handle_clip_level_change ()
 198 {
 199         begin_visual_change ();
 200         invalidate_image_cache ();
 201         end_visual_change ();
 202 }
 203
 204 void
 205 WaveView::set_fill_color (Color c)
 206 {
 207         if (c != _fill_color) {
 208                 begin_visual_change ();
 209                 invalidate_image_cache ();
 210                 Fill::set_fill_color (c);
 211                 end_visual_change ();
 212         }
 213 }
 214
 215 void
 216 WaveView::set_outline_color (Color c)
 217 {
 218         if (c != _outline_color) {
 219                 begin_visual_change ();
 220                 invalidate_image_cache ();
 221                 Outline::set_outline_color (c);
 222                 end_visual_change ();
 223         }
 224 }
 225
 226 void
 227 WaveView::set_samples_per_pixel (double samples_per_pixel)
 228 {
 229         if (samples_per_pixel != _samples_per_pixel) {
 230                 begin_change ();
 231
 232                 invalidate_image_cache ();
 233                 _samples_per_pixel = samples_per_pixel;
 234                 _bounding_box_dirty = true;
 235
 236                 end_change ();
 237         }
 238 }
 239
 240 static inline float
 241 _log_meter (float power, double lower_db, double upper_db, double non_linearity)
 242 {
 243         return (power < lower_db ? 0.0 : pow((power-lower_db)/(upper_db-lower_db), non_linearity));
 244 }
 245
 246 static inline float
 247 alt_log_meter (float power)
 248 {
 249         return _log_meter (power, -192.0, 0.0, 8.0);
 250 }
 251
 252 void
 253 WaveView::set_clip_level (double dB)
 254 {
 255         const double clip_level = dB_to_coefficient (dB);
 256         if (clip_level != _clip_level) {
 257                 _clip_level = clip_level;
 258                 ClipLevelChanged ();
 259         }
 260 }
 261
 262 void
 263 WaveView::invalidate_image_cache ()
 264 {
 265         DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 invalidates image cache and cancels current request\n", this));
 266         cancel_my_render_request ();
 267         Glib::Threads::Mutex::Lock lci (current_image_lock);
 268         _current_image.reset ();
 269 }
 270
 271 void
 272 WaveView::compute_tips (PeakData const & peak, WaveView::LineTips& tips) const
 273 {
 274         const double effective_height  = _height;
 275
 276         /* remember: canvas (and cairo) coordinate space puts the origin at the upper left.
 277
 278            So, a sample value of 1.0 (0dbFS) will be computed as:
 279
 280                  (1.0 - 1.0) * 0.5 * effective_height
 281
 282            which evaluates to 0, or the top of the image.
 283
 284            A sample value of -1.0 will be computed as
 285
 286                 (1.0 + 1.0) * 0.5 * effective height
 287
 288            which evaluates to effective height, or the bottom of the image.
 289         */
 290
 291         const double pmax = (1.0 - peak.max) * 0.5 * effective_height;
 292         const double pmin = (1.0 - peak.min) * 0.5 * effective_height;
 293
 294         /* remember that the bottom of the image (pmin) has larger y-coordinates
 295            than the top (pmax).
 296         */
 297
 298         double spread = (pmin - pmax) * 0.5;
 299
 300         /* find the nearest pixel to the nominal center. */
 301         const double center = round (pmin - spread);
 302
 303         if (spread < 1.0) {
 304                 /* minimum distance between line ends is 1 pixel, and we want it "centered" on a pixel,
 305                    as per cairo single-pixel line issues.
 306
 307                    NOTE: the caller will not draw a line between these two points if the spread is
 308                    less than 2 pixels. So only the tips.top value matters, which is where we will
 309                    draw a single pixel as part of the outline.
 310                  */
 311                 tips.top = center;
 312                 tips.bot = center + 1.0;
 313         } else {
 314                 /* round spread above and below center to an integer number of pixels */
 315                 spread = round (spread);
 316                 /* top and bottom are located equally either side of the center */
 317                 tips.top = center - spread;
 318                 tips.bot = center + spread;
 319         }
 320
 321         tips.top = min (effective_height, max (0.0, tips.top));
 322         tips.bot = min (effective_height, max (0.0, tips.bot));
 323 }
 324
 325
 326 Coord
 327 WaveView::y_extent (double s) const
 328 {
 329         assert (_shape == Rectified);
 330         return floor ((1.0 - s) * _height);
 331 }
 332
 333 void
 334 WaveView::draw_absent_image (Cairo::RefPtr<Cairo::ImageSurface>& image, PeakData* _peaks, int n_peaks) const
 335 {
 336         Cairo::RefPtr<Cairo::ImageSurface> stripe = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, _height);
 337
 338         Cairo::RefPtr<Cairo::Context> stripe_context = Cairo::Context::create (stripe);
 339         stripe_context->set_antialias (Cairo::ANTIALIAS_NONE);
 340
 341         uint32_t stripe_separation = 150;
 342         double start = - floor (_height / stripe_separation) * stripe_separation;
 343         int stripe_x = 0;
 344
 345         while (start < n_peaks) {
 346
 347                 stripe_context->move_to (start, 0);
 348                 stripe_x = start + _height;
 349                 stripe_context->line_to (stripe_x, _height);
 350                 start += stripe_separation;
 351         }
 352
 353         stripe_context->set_source_rgba (1.0, 1.0, 1.0, 1.0);
 354         stripe_context->set_line_cap (Cairo::LINE_CAP_SQUARE);
 355         stripe_context->set_line_width(50);
 356         stripe_context->stroke();
 357
 358         Cairo::RefPtr<Cairo::Context> context = Cairo::Context::create (image);
 359
 360         context->set_source_rgba (1.0, 1.0, 0.0, 0.3);
 361         context->mask (stripe, 0, 0);
 362         context->fill ();
 363 }
 364
 365 struct ImageSet {
 366         Cairo::RefPtr<Cairo::ImageSurface> wave;
 367         Cairo::RefPtr<Cairo::ImageSurface> outline;
 368         Cairo::RefPtr<Cairo::ImageSurface> clip;
 369         Cairo::RefPtr<Cairo::ImageSurface> zero;
 370
 371         ImageSet() :
 372                 wave (0), outline (0), clip (0), zero (0) {}
 373 };
 374
 375 void
 376 WaveView::draw_image (Cairo::RefPtr<Cairo::ImageSurface>& image, PeakData* _peaks, int n_peaks, boost::shared_ptr<WaveViewThreadRequest> req) const
 377 {
 378
 379         ImageSet images;
 380
 381         images.wave = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, _height);
 382         images.outline = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, _height);
 383         images.clip = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, _height);
 384         images.zero = Cairo::ImageSurface::create (Cairo::FORMAT_A8, n_peaks, _height);
 385
 386         Cairo::RefPtr<Cairo::Context> wave_context = Cairo::Context::create (images.wave);
 387         Cairo::RefPtr<Cairo::Context> outline_context = Cairo::Context::create (images.outline);
 388         Cairo::RefPtr<Cairo::Context> clip_context = Cairo::Context::create (images.clip);
 389         Cairo::RefPtr<Cairo::Context> zero_context = Cairo::Context::create (images.zero);
 390         wave_context->set_antialias (Cairo::ANTIALIAS_NONE);
 391         outline_context->set_antialias (Cairo::ANTIALIAS_NONE);
 392         clip_context->set_antialias (Cairo::ANTIALIAS_NONE);
 393         zero_context->set_antialias (Cairo::ANTIALIAS_NONE);
 394
 395         boost::scoped_array<LineTips> tips (new LineTips[n_peaks]);
 396
 397         /* Clip level nominally set to -0.9dBFS to account for inter-sample
 398            interpolation possibly clipping (value may be too low).
 399
 400            We adjust by the region's own gain (but note: not by any gain
 401            automation or its gain envelope) so that clip indicators are closer
 402            to providing data about on-disk data. This multiplication is
 403            needed because the data we get from AudioRegion::read_peaks()
 404            has been scaled by scale_amplitude() already.
 405         */
 406
 407         const double clip_level = _clip_level * _region_amplitude;
 408
 409         if (_shape == WaveView::Rectified) {
 410
 411                 /* each peak is a line from the bottom of the waveview
 412                  * to a point determined by max (_peaks[i].max,
 413                  * _peaks[i].min)
 414                  */
 415
 416                 if (_logscaled) {
 417                         for (int i = 0; i < n_peaks; ++i) {
 418
 419                                 tips[i].bot = height() - 1.0;
 420                                 const double p = alt_log_meter (fast_coefficient_to_dB (max (fabs (_peaks[i].max), fabs (_peaks[i].min))));
 421                                 tips[i].top = y_extent (p);
 422                                 tips[i].spread = p * _height;
 423
 424                                 if (_peaks[i].max >= clip_level) {
 425                                         tips[i].clip_max = true;
 426                                 }
 427
 428                                 if (-(_peaks[i].min) >= clip_level) {
 429                                         tips[i].clip_min = true;
 430                                 }
 431                         }
 432
 433                 } else {
 434                         for (int i = 0; i < n_peaks; ++i) {
 435
 436                                 tips[i].bot = height() - 1.0;
 437                                 const double p = max(fabs (_peaks[i].max), fabs (_peaks[i].min));
 438                                 tips[i].top = y_extent (p);
 439                                 tips[i].spread = p * _height;
 440                                 if (p >= clip_level) {
 441                                         tips[i].clip_max = true;
 442                                 }
 443                         }
 444
 445                 }
 446
 447         } else {
 448
 449                 if (_logscaled) {
 450                         for (int i = 0; i < n_peaks; ++i) {
 451                                 PeakData p;
 452                                 p.max = _peaks[i].max;
 453                                 p.min = _peaks[i].min;
 454
 455                                 if (_peaks[i].max >= clip_level) {
 456                                         tips[i].clip_max = true;
 457                                 }
 458                                 if (-(_peaks[i].min) >= clip_level) {
 459                                         tips[i].clip_min = true;
 460                                 }
 461
 462                                 if (p.max > 0.0) {
 463                                         p.max = alt_log_meter (fast_coefficient_to_dB (p.max));
 464                                 } else if (p.max < 0.0) {
 465                                         p.max =-alt_log_meter (fast_coefficient_to_dB (-p.max));
 466                                 } else {
 467                                         p.max = 0.0;
 468                                 }
 469
 470                                 if (p.min > 0.0) {
 471                                         p.min = alt_log_meter (fast_coefficient_to_dB (p.min));
 472                                 } else if (p.min < 0.0) {
 473                                         p.min = -alt_log_meter (fast_coefficient_to_dB (-p.min));
 474                                 } else {
 475                                         p.min = 0.0;
 476                                 }
 477
 478                                 compute_tips (p, tips[i]);
 479                                 tips[i].spread = tips[i].bot - tips[i].top;
 480                         }
 481
 482                 } else {
 483                         for (int i = 0; i < n_peaks; ++i) {
 484                                 if (_peaks[i].max >= clip_level) {
 485                                         tips[i].clip_max = true;
 486                                 }
 487                                 if (-(_peaks[i].min) >= clip_level) {
 488                                         tips[i].clip_min = true;
 489                                 }
 490
 491                                 compute_tips (_peaks[i], tips[i]);
 492                                 tips[i].spread = tips[i].bot - tips[i].top;
 493                         }
 494
 495                 }
 496         }
 497
 498         if (req->should_stop()) {
 499                 return;
 500         }
 501
 502         Color alpha_one = rgba_to_color (0, 0, 0, 1.0);
 503
 504         set_source_rgba (wave_context, alpha_one);
 505         set_source_rgba (outline_context, alpha_one);
 506         set_source_rgba (clip_context, alpha_one);
 507         set_source_rgba (zero_context, alpha_one);
 508
 509         /* ensure single-pixel lines */
 510
 511         wave_context->set_line_width (1.0);
 512         wave_context->translate (0.5, 0.5);
 513
 514         outline_context->set_line_width (1.0);
 515         outline_context->translate (0.5, 0.5);
 516
 517         clip_context->set_line_width (1.0);
 518         clip_context->translate (0.5, 0.5);
 519
 520         zero_context->set_line_width (1.0);
 521         zero_context->translate (0.5, 0.5);
 522
 523         /* the height of the clip-indicator should be at most 7 pixels,
 524          * or 5% of the height of the waveview item.
 525          */
 526
 527         const double clip_height = min (7.0, ceil (_height * 0.05));
 528
 529         /* There are 3 possible components to draw at each x-axis position: the
 530            waveform "line", the zero line and an outline/clip indicator.  We
 531            have to decide which of the 3 to draw at each position, pixel by
 532            pixel. This makes the rendering less efficient but it is the only
 533            way I can see to do this correctly.
 534
 535            To avoid constant source swapping and stroking, we draw the components separately
 536            onto four alpha only image surfaces for use as a mask.
 537
 538            With only 1 pixel of spread between the top and bottom of the line,
 539            we just draw the upper outline/clip indicator.
 540
 541            With 2 pixels of spread, we draw the upper and lower outline clip
 542            indicators.
 543
 544            With 3 pixels of spread we draw the upper and lower outline/clip
 545            indicators and at least 1 pixel of the waveform line.
 546
 547            With 5 pixels of spread, we draw all components.
 548
 549            We can do rectified as two separate passes because we have a much
 550            easier decision regarding whether to draw the waveform line. We
 551            always draw the clip/outline indicators.
 552         */
 553
 554         if (_shape == WaveView::Rectified) {
 555
 556                 for (int i = 0; i < n_peaks; ++i) {
 557
 558                         /* waveform line */
 559
 560                         if (tips[i].spread >= 1.0) {
 561                                 wave_context->move_to (i, tips[i].top);
 562                                 wave_context->line_to (i, tips[i].bot);
 563                         }
 564
 565                         /* clip indicator */
 566
 567                         if (_global_show_waveform_clipping && (tips[i].clip_max || tips[i].clip_min)) {
 568                                 clip_context->move_to (i, tips[i].top);
 569                                 /* clip-indicating upper terminal line */
 570                                 clip_context->rel_line_to (0, min (clip_height, ceil(tips[i].spread + .5)));
 571                         } else {
 572                                 outline_context->move_to (i, tips[i].top);
 573                                 /* normal upper terminal dot */
 574                                 outline_context->rel_line_to (0, -1.0);
 575                         }
 576                 }
 577
 578                 wave_context->stroke ();
 579                 clip_context->stroke ();
 580                 outline_context->stroke ();
 581
 582         } else {
 583                 const int height_zero = floor( _height * .5);
 584
 585                 for (int i = 0; i < n_peaks; ++i) {
 586
 587                         /* waveform line */
 588
 589                         if (tips[i].spread >= 2.0) {
 590                                 wave_context->move_to (i, tips[i].top);
 591                                 wave_context->line_to (i, tips[i].bot);
 592                         }
 593
 594                         /* draw square waves and other discontiguous points clearly */
 595                         if (i > 0) {
 596                                 if (tips[i-1].top + 2 < tips[i].top) {
 597                                         wave_context->move_to (i-1, tips[i-1].top);
 598                                         wave_context->line_to (i-1, (tips[i].bot + tips[i-1].top)/2);
 599                                         wave_context->move_to (i, (tips[i].bot + tips[i-1].top)/2);
 600                                         wave_context->line_to (i, tips[i].top);
 601                                 } else if (tips[i-1].bot > tips[i].bot + 2) {
 602                                         wave_context->move_to (i-1, tips[i-1].bot);
 603                                         wave_context->line_to (i-1, (tips[i].top + tips[i-1].bot)/2);
 604                                         wave_context->move_to (i, (tips[i].top + tips[i-1].bot)/2);
 605                                         wave_context->line_to (i, tips[i].bot);
 606                                 }
 607                         }
 608
 609                         /* zero line, show only if there is enough spread
 610                         or the waveform line does not cross zero line */
 611
 612                         if (show_zero_line() && ((tips[i].spread >= 5.0) || (tips[i].top > height_zero ) || (tips[i].bot < height_zero)) ) {
 613                                 zero_context->move_to (i, height_zero);
 614                                 zero_context->rel_line_to (1.0, 0);
 615                         }
 616
 617                         if (tips[i].spread > 1.0) {
 618                                 bool clipped = false;
 619                                 /* outline/clip indicators */
 620                                 if (_global_show_waveform_clipping && tips[i].clip_max) {
 621                                         clip_context->move_to (i, tips[i].top);
 622                                         /* clip-indicating upper terminal line */
 623                                         clip_context->rel_line_to (0, min (clip_height, ceil(tips[i].spread + 0.5)));
 624                                         clipped = true;
 625                                 }
 626
 627                                 if (_global_show_waveform_clipping && tips[i].clip_min) {
 628                                         clip_context->move_to (i, tips[i].bot);
 629                                         /* clip-indicating lower terminal line */
 630                                         clip_context->rel_line_to (0, - min (clip_height, ceil(tips[i].spread + 0.5)));
 631                                         clipped = true;
 632                                 }
 633
 634                                 if (!clipped && tips[i].spread > 2.0) {
 635                                         /* only draw the outline if the spread
 636                                            implies 3 or more pixels (so that we see 1
 637                                            white pixel in the middle).
 638                                         */
 639                                         outline_context->move_to (i, tips[i].bot);
 640                                         /* normal lower terminal dot; line moves up */
 641                                         outline_context->rel_line_to (0, -1.0);
 642
 643                                         outline_context->move_to (i, tips[i].top);
 644                                         /* normal upper terminal dot, line moves down */
 645                                         outline_context->rel_line_to (0, 1.0);
 646                                 }
 647                         } else {
 648                                 bool clipped = false;
 649                                 /* outline/clip indicator */
 650                                 if (_global_show_waveform_clipping && (tips[i].clip_max || tips[i].clip_min)) {
 651                                         clip_context->move_to (i, tips[i].top);
 652                                         /* clip-indicating upper / lower terminal line */
 653                                         clip_context->rel_line_to (0, 1.0);
 654                                         clipped = true;
 655                                 }
 656
 657                                 if (!clipped) {
 658                                         /* special case where only 1 pixel of
 659                                          * the waveform line is drawn (and
 660                                          * nothing else).
 661                                          *
 662                                          * we draw a 1px "line", pretending
 663                                          * that the span is 1.0 (whether it is
 664                                          * zero or 1.0)
 665                                          */
 666                                         wave_context->move_to (i, tips[i].top);
 667                                         wave_context->rel_line_to (0, 1.0);
 668                                 }
 669                         }
 670                 }
 671
 672                 wave_context->stroke ();
 673                 outline_context->stroke ();
 674                 clip_context->stroke ();
 675                 zero_context->stroke ();
 676         }
 677
 678         if (req->should_stop()) {
 679                 return;
 680         }
 681
 682         Cairo::RefPtr<Cairo::Context> context = Cairo::Context::create (image);
 683
 684         /* Here we set a source colour and use the various components as a mask. */
 685
 686         if (gradient_depth() != 0.0) {
 687
 688                 Cairo::RefPtr<Cairo::LinearGradient> gradient (Cairo::LinearGradient::create (0, 0, 0, _height));
 689
 690                 double stops[3];
 691
 692                 double r, g, b, a;
 693
 694                 if (_shape == Rectified) {
 695                         stops[0] = 0.1;
 696                         stops[1] = 0.3;
 697                         stops[2] = 0.9;
 698                 } else {
 699                         stops[0] = 0.1;
 700                         stops[1] = 0.5;
 701                         stops[2] = 0.9;
 702                 }
 703
 704                 color_to_rgba (_fill_color, r, g, b, a);
 705                 gradient->add_color_stop_rgba (stops[1], r, g, b, a);
 706                 /* generate a new color for the middle of the gradient */
 707                 double h, s, v;
 708                 color_to_hsv (_fill_color, h, s, v);
 709                 /* change v towards white */
 710                 v *= 1.0 - gradient_depth();
 711                 Color center = hsva_to_color (h, s, v, a);
 712                 color_to_rgba (center, r, g, b, a);
 713
 714                 gradient->add_color_stop_rgba (stops[0], r, g, b, a);
 715                 gradient->add_color_stop_rgba (stops[2], r, g, b, a);
 716
 717                 context->set_source (gradient);
 718         } else {
 719                 set_source_rgba (context, _fill_color);
 720         }
 721
 722         if (req->should_stop()) {
 723                 return;
 724         }
 725
 726         context->mask (images.wave, 0, 0);
 727         context->fill ();
 728
 729         set_source_rgba (context, _outline_color);
 730         context->mask (images.outline, 0, 0);
 731         context->fill ();
 732
 733         set_source_rgba (context, _clip_color);
 734         context->mask (images.clip, 0, 0);
 735         context->fill ();
 736
 737         set_source_rgba (context, _zero_color);
 738         context->mask (images.zero, 0, 0);
 739         context->fill ();
 740 }
 741
 742 boost::shared_ptr<WaveViewCache::Entry>
 743 WaveView::cache_request_result (boost::shared_ptr<WaveViewThreadRequest> req) const
 744 {
 745         if (!req->image) {
 746                 cerr << "asked to cache null image!!!\n";
 747                 return boost::shared_ptr<WaveViewCache::Entry> ();
 748         }
 749
 750         boost::shared_ptr<WaveViewCache::Entry> ret (new WaveViewCache::Entry (req->channel,
 751                                                                                req->height,
 752                                                                                req->amplitude,
 753                                                                                req->fill_color,
 754                                                                                req->samples_per_pixel,
 755                                                                                req->start,
 756                                                                                req->end,
 757                                                                                req->image));
 758         images->add (_region->audio_source (_channel), ret);
 759
 760         /* consolidate cache first (removes fully-contained
 761          * duplicate images)
 762          */
 763
 764         images->consolidate_image_cache (_region->audio_source (_channel),
 765                                          req->channel, req->height, req->amplitude,
 766                                          req->fill_color, req->samples_per_pixel);
 767
 768         return ret;
 769 }
 770
 771 boost::shared_ptr<WaveViewCache::Entry>
 772 WaveView::get_image (framepos_t start, framepos_t end, bool& full_image) const
 773 {
 774         boost::shared_ptr<WaveViewCache::Entry> ret;
 775
 776         full_image = true;
 777
 778         /* this is called from a ::render() call, when we need an image to
 779            draw with.
 780         */
 781
 782         DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 needs image from %2 .. %3\n", name, start, end));
 783
 784
 785         {
 786                 Glib::Threads::Mutex::Lock lmq (request_queue_lock);
 787
 788                 /* if there's a draw request outstanding, check to see if we
 789                  * have an image there. if so, use it (and put it in the cache
 790                  * while we're here.
 791                  */
 792
 793                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 CR %2 stop? %3 image %4\n", this, current_request,
 794                                                               (current_request ? current_request->should_stop() : false),
 795                                                               (current_request ? current_request->image : 0)));
 796
 797                 if (current_request && !current_request->should_stop() && current_request->image) {
 798
 799                         /* put the image into the cache so that other
 800                          * WaveViews can use it if it is useful
 801                          */
 802
 803                         if (current_request->start <= start && current_request->end >= end) {
 804
 805                                 ret.reset (new WaveViewCache::Entry (current_request->channel,
 806                                                                      current_request->height,
 807                                                                      current_request->amplitude,
 808                                                                      current_request->fill_color,
 809                                                                      current_request->samples_per_pixel,
 810                                                                      current_request->start,
 811                                                                      current_request->end,
 812                                                                      current_request->image));
 813
 814                                 cache_request_result (current_request);
 815                                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1: got image from completed request, spans %2..%3\n",
 816                                                                               name, current_request->start, current_request->end));
 817                         }
 818
 819                         /* drop our handle on the current request */
 820                         current_request.reset ();
 821                 }
 822         }
 823
 824         if (!ret) {
 825
 826                 /* no current image draw request, so look in the cache */
 827
 828                 ret = get_image_from_cache (start, end, full_image);
 829                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1: lookup from cache gave %2 (full %3)\n",
 830                                                               name, ret, full_image));
 831
 832         }
 833
 834
 835
 836         if (!ret || !full_image) {
 837
 838                 if ((rendered && get_image_in_thread) || always_get_image_in_thread) {
 839
 840                         DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1: generating image in caller thread\n", name));
 841
 842                         boost::shared_ptr<WaveViewThreadRequest> req (new WaveViewThreadRequest);
 843
 844                         req->type = WaveViewThreadRequest::Draw;
 845                         req->start = start;
 846                         req->end = end;
 847                         req->samples_per_pixel = _samples_per_pixel;
 848                         req->region = _region; /* weak ptr, to avoid storing a reference in the request queue */
 849                         req->channel = _channel;
 850                         req->height = _height;
 851                         req->fill_color = _fill_color;
 852                         req->amplitude = _region_amplitude * _amplitude_above_axis;
 853                         req->width = desired_image_width ();
 854
 855                         /* draw image in this (the GUI thread) */
 856
 857                         generate_image (req, false);
 858
 859                         /* cache the result */
 860
 861                         ret = cache_request_result (req);
 862
 863                         /* reset this so that future missing images are
 864                          * generated in a a worker thread.
 865                          */
 866
 867                         get_image_in_thread = false;
 868
 869                 } else {
 870                         queue_get_image (_region, start, end);
 871                 }
 872         }
 873
 874         if (ret) {
 875                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 got an image from %2 .. %3 (full ? %4)\n", name, ret->start, ret->end, full_image));
 876         } else {
 877                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 no useful image available\n", name));
 878         }
 879
 880         return ret;
 881 }
 882
 883 boost::shared_ptr<WaveViewCache::Entry>
 884 WaveView::get_image_from_cache (framepos_t start, framepos_t end, bool& full) const
 885 {
 886         if (!images) {
 887                 return boost::shared_ptr<WaveViewCache::Entry>();
 888         }
 889
 890         return images->lookup_image (_region->audio_source (_channel), start, end, _channel,
 891                                      _height, _region_amplitude * _amplitude_above_axis, _fill_color, _samples_per_pixel, full);
 892 }
 893
 894 framecnt_t
 895 WaveView::desired_image_width () const
 896 {
 897         /* compute how wide the image should be, in samples.
 898          *
 899          * We want at least 1 canvas width's worth, but if that
 900          * represents less than 1/10th of a second, use 1/10th of
 901          * a second instead.
 902          */
 903
 904         framecnt_t canvas_width_samples = _canvas->visible_area().width() * _samples_per_pixel;
 905         const framecnt_t one_tenth_of_second = _region->session().frame_rate() / 10;
 906
 907         if (canvas_width_samples > one_tenth_of_second) {
 908                 return  canvas_width_samples;
 909         }
 910
 911         return one_tenth_of_second;
 912 }
 913
 914 void
 915 WaveView::queue_get_image (boost::shared_ptr<const ARDOUR::Region> region, framepos_t start, framepos_t end) const
 916 {
 917         boost::shared_ptr<WaveViewThreadRequest> req (new WaveViewThreadRequest);
 918
 919         req->type = WaveViewThreadRequest::Draw;
 920         req->start = start;
 921         req->end = end;
 922         req->samples_per_pixel = _samples_per_pixel;
 923         req->region = _region; /* weak ptr, to avoid storing a reference in the request queue */
 924         req->channel = _channel;
 925         req->height = _height;
 926         req->fill_color = _fill_color;
 927         req->amplitude = _region_amplitude * _amplitude_above_axis;
 928         req->width = desired_image_width ();
 929
 930         if (current_request) {
 931                 /* this will stop rendering in progress (which might otherwise
 932                    be long lived) for any current request.
 933                 */
 934                 current_request->cancel ();
 935         }
 936
 937         start_drawing_thread ();
 938
 939         /* swap requests (protected by lock) */
 940
 941         {
 942                 Glib::Threads::Mutex::Lock lm (request_queue_lock);
 943                 current_request = req;
 944
 945                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 now has current request %2\n", this, req));
 946
 947                 if (request_queue.insert (this).second) {
 948                         /* this waveview was not already in the request queue, make sure we wake
 949                            the rendering thread in case it is asleep.
 950                         */
 951                         request_cond.signal ();
 952                 }
 953         }
 954 }
 955
 956 void
 957 WaveView::generate_image (boost::shared_ptr<WaveViewThreadRequest> req, bool in_render_thread) const
 958 {
 959         if (!req->should_stop()) {
 960
 961                 /* sample position is canonical here, and we want to generate
 962                  * an image that spans about 3x the canvas width. We get to that
 963                  * width by using an image sample count of the screen width added
 964                  * on each side of the desired image center.
 965                  */
 966
 967                 const framepos_t center = req->start + ((req->end - req->start) / 2);
 968                 const framecnt_t image_samples = req->width;
 969
 970                 /* we can request data from anywhere in the Source, between 0 and its length
 971                  */
 972
 973                 framepos_t sample_start = max (_region_start, (center - image_samples));
 974                 framepos_t sample_end = min (center + image_samples, region_end());
 975                 const int n_peaks = llrintf ((sample_end - sample_start)/ (req->samples_per_pixel));
 976
 977                 boost::scoped_array<ARDOUR::PeakData> peaks (new PeakData[n_peaks]);
 978
 979                 /* Note that Region::read_peaks() takes a start position based on an
 980                    offset into the Region's **SOURCE**, rather than an offset into
 981                    the Region itself.
 982                 */
 983
 984                 framecnt_t peaks_read = _region->read_peaks (peaks.get(), n_peaks,
 985                                                              sample_start, sample_end - sample_start,
 986                                                              req->channel,
 987                                                              req->samples_per_pixel);
 988
 989                 req->image = Cairo::ImageSurface::create (Cairo::FORMAT_ARGB32, n_peaks, req->height);
 990                 /* make sure we record the sample positions that were actually used */
 991                 req->start = sample_start;
 992                 req->end = sample_end;
 993
 994                 if (peaks_read > 0) {
 995
 996                         /* region amplitude will have been used to generate the
 997                          * peak values already, but not the visual-only
 998                          * amplitude_above_axis. So apply that here before
 999                          * rendering.
1000                          */
1001
1002                         if (_amplitude_above_axis != 1.0) {
1003                                 for (framecnt_t i = 0; i < n_peaks; ++i) {
1004                                         peaks[i].max *= _amplitude_above_axis;
1005                                         peaks[i].min *= _amplitude_above_axis;
1006                                 }
1007                         }
1008
1009                         draw_image (req->image, peaks.get(), n_peaks, req);
1010                 } else {
1011                         draw_absent_image (req->image, peaks.get(), n_peaks);
1012                 }
1013         } else {
1014                 cerr << "Request stopped before image generation\n";
1015         }
1016
1017         if (in_render_thread && !req->should_stop()) {
1018                 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));
1019                 const_cast<WaveView*>(this)->ImageReady (); /* emit signal */
1020         }
1021
1022         return;
1023 }
1024
1025 /** Given a waveform that starts at window x-coordinate @param wave_origin
1026  * and the first pixel that we will actually draw @param draw_start, return
1027  * the offset into an image of the entire waveform that we will need to use.
1028  *
1029  * Note: most of our cached images are NOT of the entire waveform, this is just
1030  * computationally useful when determining which the sample range span for
1031  * the image we need.
1032  */
1033 static inline double
1034 window_to_image (double wave_origin, double image_start)
1035 {
1036         return image_start - wave_origin;
1037 }
1038
1039 void
1040 WaveView::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
1041 {
1042         assert (_samples_per_pixel != 0);
1043
1044         if (!_region) {
1045                 return;
1046         }
1047
1048         DEBUG_TRACE (DEBUG::WaveView, string_compose ("render %1 at %2\n", this, g_get_monotonic_time()));
1049
1050         /* a WaveView is intimately connected to an AudioRegion. It will
1051          * display the waveform within the region, anywhere from the start of
1052          * the region to its end.
1053          *
1054          * the area we've been aked to render may overlap with area covered
1055          * by the region in any of the normal ways:
1056          *
1057          *  - it may begin and end within the area covered by the region
1058          *  - it may start before and end after the area covered by region
1059          *  - it may start before and end within the area covered by the region
1060          *  - it may start within and end after the area covered by the region
1061          *  - it may be precisely coincident with the area covered by region.
1062          *
1063          * So let's start by determining the area covered by the region, in
1064          * window coordinates. It begins at zero (in item coordinates for this
1065          * waveview, and extends to region_length() / _samples_per_pixel.
1066          */
1067
1068         Rect self = item_to_window (Rect (0.0, 0.0, region_length() / _samples_per_pixel, _height));
1069
1070         // cerr << name << " RENDER " << area << " self = " << self << endl;
1071
1072         /* Now lets get the intersection with the area we've been asked to draw */
1073
1074         boost::optional<Rect> d = self.intersection (area);
1075
1076         if (!d) {
1077                 return;
1078         }
1079
1080         Rect draw = d.get();
1081
1082         /* "draw" is now a rectangle that defines the rectangle we need to
1083          * update/render the waveview into, in window coordinate space.
1084          */
1085
1086         /* window coordinates - pixels where x=0 is the left edge of the canvas
1087          * window. We round down in case we were asked to
1088          * draw "between" pixels at the start and/or end.
1089          */
1090
1091         double draw_start = floor (draw.x0);
1092         const double draw_end = floor (draw.x1);
1093
1094         // cerr << "Need to draw " << draw_start << " .. " << draw_end << " vs. " << area << " and self = " << self << endl;
1095
1096         /* image coordnates: pixels where x=0 is the start of this waveview,
1097          * wherever it may be positioned. thus image_start=N means "an image
1098          * that begins N pixels after the start of region that this waveview is
1099          * representing.
1100          */
1101
1102         const framepos_t image_start = window_to_image (self.x0, draw_start);
1103         const framepos_t image_end = window_to_image (self.x0, draw_end);
1104
1105         // cerr << "Image/WV space: " << image_start << " .. " << image_end << endl;
1106
1107         /* sample coordinates - note, these are not subject to rounding error
1108          *
1109          * "sample_start = N" means "the first sample we need to represent is N
1110          * samples after the first sample of the region"
1111          */
1112
1113         framepos_t sample_start = _region_start + (image_start * _samples_per_pixel);
1114         framepos_t sample_end   = _region_start + (image_end * _samples_per_pixel);
1115
1116         // cerr << "Sample space: " << sample_start << " .. " << sample_end << " @ " << _samples_per_pixel << " rs = " << _region_start << endl;
1117
1118         /* sample_start and sample_end are bounded by the region
1119          * limits. sample_start, because of the was just computed, must already
1120          * be greater than or equal to the _region_start value.
1121          */
1122
1123         sample_end = min (region_end(), sample_end);
1124
1125         // cerr << debug_name() << " will need image spanning " << sample_start << " .. " << sample_end << " region spans " << _region_start << " .. " << region_end() << endl;
1126
1127         double image_origin_in_self_coordinates;
1128         boost::shared_ptr<WaveViewCache::Entry> image_to_draw;
1129
1130         Glib::Threads::Mutex::Lock lci (current_image_lock);
1131         if (_current_image) {
1132
1133                 /* check it covers the right sample range */
1134
1135                 if (_current_image->start > sample_start || _current_image->end < sample_end) {
1136                         /* doesn't cover the area we need ... reset */
1137                         _current_image.reset ();
1138                 } else {
1139                         /* timestamp our continuing use of this image/cache entry */
1140                         images->use (_region->audio_source (_channel), _current_image);
1141                         image_to_draw = _current_image;
1142                 }
1143         }
1144
1145         if (!image_to_draw) {
1146
1147                 /* look it up */
1148
1149                 bool full_image;
1150                 image_to_draw = get_image (sample_start, sample_end, full_image);
1151
1152                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 image to draw = %2 (full? %3)\n", name, image_to_draw, full_image));
1153
1154                 if (!image_to_draw) {
1155                         /* image not currently available. A redraw will be scheduled
1156                            when it is ready.
1157                         */
1158                         return;
1159                 }
1160
1161                 if (full_image) {
1162                         /* found an image that covers our entire sample range,
1163                          * so keep a reference to it.
1164                          */
1165                         _current_image = image_to_draw;
1166                 }
1167         }
1168
1169         /* compute the first pixel of the image that should be used when we
1170          * render the specified range.
1171          */
1172
1173         image_origin_in_self_coordinates = (image_to_draw->start - _region_start) / _samples_per_pixel;
1174
1175         if (_start_shift && (sample_start == _region_start) && (self.x0 == draw.x0)) {
1176                 /* we are going to draw the first pixel for this region, but
1177                    we may not want this to overlap a border around the
1178                    waveform. If so, _start_shift will be set.
1179                 */
1180                 //cerr << name.substr (23) << " ss = " << sample_start << " rs = " << _region_start << " sf = " << _start_shift << " ds = " << draw_start << " self = " << self << " draw = " << draw << endl;
1181                 //draw_start += _start_shift;
1182                 //image_origin_in_self_coordinates += _start_shift;
1183         }
1184
1185         /* the image may only be a best-effort ... it may not span the entire
1186          * range requested, though it is guaranteed to cover the start. So
1187          * determine how many pixels we can actually draw.
1188          */
1189
1190         double draw_width;
1191
1192         if (image_to_draw != _current_image) {
1193                 lci.release ();
1194
1195                 /* the image is guaranteed to start at or before
1196                  * draw_start. But if it starts before draw_start, that reduces
1197                  * the maximum available width we can render with.
1198                  *
1199                  * so .. clamp the draw width to the smaller of what we need to
1200                  * draw or the available width of the image.
1201                  */
1202
1203                 draw_width = min ((double) image_to_draw->image->get_width() - (draw_start - image_to_draw->start),
1204                                   (draw_end - draw_start));
1205
1206
1207                 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),
1208                                                               image_to_draw->image->get_width(), image_origin_in_self_coordinates,
1209                                                               image_to_draw->start, _region_start));
1210         } else {
1211                 draw_width = draw_end - draw_start;
1212                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("use current image, span entire render width %1..%2\n", draw_start, draw_end));
1213         }
1214
1215         context->rectangle (draw_start, draw.y0, draw_width, draw.height());
1216
1217         /* round image origin position to an exact pixel in device space to
1218          * avoid blurring
1219          */
1220
1221         double x  = self.x0 + image_origin_in_self_coordinates;
1222         double y  = self.y0;
1223         context->user_to_device (x, y);
1224         x = round (x);
1225         y = round (y);
1226         context->device_to_user (x, y);
1227
1228         /* the coordinates specify where in "user coordinates" (i.e. what we
1229          * generally call "canvas coordinates" in this code) the image origin
1230          * will appear. So specifying (10,10) will put the upper left corner of
1231          * the image at (10,10) in user space.
1232          */
1233
1234         context->set_source (image_to_draw->image, x, y);
1235         context->fill ();
1236
1237         /* image obtained, some of it painted to display: we are rendered.
1238            Future calls to get_image_in_thread are now meaningful.
1239         */
1240
1241         rendered = true;
1242 }
1243
1244 void
1245 WaveView::compute_bounding_box () const
1246 {
1247         if (_region) {
1248                 _bounding_box = Rect (0.0, 0.0, region_length() / _samples_per_pixel, _height);
1249         } else {
1250                 _bounding_box = boost::optional<Rect> ();
1251         }
1252
1253         _bounding_box_dirty = false;
1254 }
1255
1256 void
1257 WaveView::set_height (Distance height)
1258 {
1259         if (height != _height) {
1260                 begin_change ();
1261
1262                 invalidate_image_cache ();
1263                 _height = height;
1264                 get_image_in_thread = true;
1265
1266                 _bounding_box_dirty = true;
1267                 end_change ();
1268         }
1269 }
1270
1271 void
1272 WaveView::set_channel (int channel)
1273 {
1274         if (channel != _channel) {
1275                 begin_change ();
1276
1277                 invalidate_image_cache ();
1278                 _channel = channel;
1279
1280                 _bounding_box_dirty = true;
1281                 end_change ();
1282         }
1283 }
1284
1285 void
1286 WaveView::set_logscaled (bool yn)
1287 {
1288         if (_logscaled != yn) {
1289                 begin_visual_change ();
1290                 invalidate_image_cache ();
1291                 _logscaled = yn;
1292                 end_visual_change ();
1293         }
1294 }
1295
1296 void
1297 WaveView::gain_changed ()
1298 {
1299         begin_visual_change ();
1300         invalidate_image_cache ();
1301         _region_amplitude = _region->scale_amplitude ();
1302         get_image_in_thread = true;
1303         end_visual_change ();
1304 }
1305
1306 void
1307 WaveView::set_zero_color (Color c)
1308 {
1309         if (_zero_color != c) {
1310                 begin_visual_change ();
1311                 invalidate_image_cache ();
1312                 _zero_color = c;
1313                 end_visual_change ();
1314         }
1315 }
1316
1317 void
1318 WaveView::set_clip_color (Color c)
1319 {
1320         if (_clip_color != c) {
1321                 begin_visual_change ();
1322                 invalidate_image_cache ();
1323                 _clip_color = c;
1324                 end_visual_change ();
1325         }
1326 }
1327
1328 void
1329 WaveView::set_show_zero_line (bool yn)
1330 {
1331         if (_show_zero != yn) {
1332                 begin_visual_change ();
1333                 invalidate_image_cache ();
1334                 _show_zero = yn;
1335                 end_visual_change ();
1336         }
1337 }
1338
1339 void
1340 WaveView::set_shape (Shape s)
1341 {
1342         if (_shape != s) {
1343                 begin_visual_change ();
1344                 invalidate_image_cache ();
1345                 _shape = s;
1346                 end_visual_change ();
1347         }
1348 }
1349
1350 void
1351 WaveView::set_amplitude_above_axis (double a)
1352 {
1353         if (fabs (_amplitude_above_axis - a) > 0.01) {
1354                 begin_visual_change ();
1355                 invalidate_image_cache ();
1356                 _amplitude_above_axis = a;
1357                 get_image_in_thread = true;
1358                 end_visual_change ();
1359         }
1360 }
1361
1362 void
1363 WaveView::set_global_shape (Shape s)
1364 {
1365         if (_global_shape != s) {
1366                 _global_shape = s;
1367                 if (images) {
1368                         images->clear_cache ();
1369                 }
1370                 VisualPropertiesChanged (); /* EMIT SIGNAL */
1371         }
1372 }
1373
1374 void
1375 WaveView::set_global_logscaled (bool yn)
1376 {
1377         if (_global_logscaled != yn) {
1378                 _global_logscaled = yn;
1379                 if (images) {
1380                         images->clear_cache ();
1381                 }
1382                 VisualPropertiesChanged (); /* EMIT SIGNAL */
1383         }
1384 }
1385
1386 framecnt_t
1387 WaveView::region_length() const
1388 {
1389         return _region->length() - (_region_start - _region->start());
1390 }
1391
1392 framepos_t
1393 WaveView::region_end() const
1394 {
1395         return _region_start + region_length();
1396 }
1397
1398 void
1399 WaveView::set_region_start (frameoffset_t start)
1400 {
1401         if (!_region) {
1402                 return;
1403         }
1404
1405         if (_region_start == start) {
1406                 return;
1407         }
1408
1409         begin_change ();
1410         _region_start = start;
1411         _bounding_box_dirty = true;
1412         end_change ();
1413 }
1414
1415 void
1416 WaveView::region_resized ()
1417 {
1418         /* Called when the region start or end (thus length) has changed.
1419         */
1420
1421         if (!_region) {
1422                 return;
1423         }
1424
1425         begin_change ();
1426         _region_start = _region->start();
1427         _bounding_box_dirty = true;
1428         end_change ();
1429 }
1430
1431 void
1432 WaveView::set_global_gradient_depth (double depth)
1433 {
1434         if (_global_gradient_depth != depth) {
1435                 _global_gradient_depth = depth;
1436                 VisualPropertiesChanged (); /* EMIT SIGNAL */
1437         }
1438 }
1439
1440 void
1441 WaveView::set_global_show_waveform_clipping (bool yn)
1442 {
1443         if (_global_show_waveform_clipping != yn) {
1444                 _global_show_waveform_clipping = yn;
1445                 ClipLevelChanged ();
1446         }
1447 }
1448
1449 void
1450 WaveView::set_start_shift (double pixels)
1451 {
1452         if (pixels < 0) {
1453                 return;
1454         }
1455
1456         begin_visual_change ();
1457         _start_shift = pixels;
1458         end_visual_change ();
1459 }
1460
1461 void
1462 WaveView::cancel_my_render_request () const
1463 {
1464         if (!images) {
1465                 return;
1466         }
1467
1468         /* try to stop any current rendering of the request, or prevent it from
1469          * ever starting up.
1470          */
1471
1472         if (current_request) {
1473                 current_request->cancel ();
1474         }
1475
1476         Glib::Threads::Mutex::Lock lm (request_queue_lock);
1477
1478         /* now remove it from the queue and reset our request pointer so that
1479            have no outstanding request (that we know about)
1480         */
1481
1482         request_queue.erase (this);
1483         current_request.reset ();
1484         DEBUG_TRACE (DEBUG::WaveView, string_compose ("%1 now has no request %2\n", this));
1485
1486 }
1487
1488 void
1489 WaveView::set_image_cache_size (uint64_t sz)
1490 {
1491         if (!images) {
1492                 images = new WaveViewCache;
1493         }
1494
1495         images->set_image_cache_threshold (sz);
1496 }
1497
1498 /*-------------------------------------------------*/
1499
1500 void
1501 WaveView::start_drawing_thread ()
1502 {
1503         if (!_drawing_thread) {
1504                 _drawing_thread = Glib::Threads::Thread::create (sigc::ptr_fun (WaveView::drawing_thread));
1505         }
1506 }
1507
1508 void
1509 WaveView::stop_drawing_thread ()
1510 {
1511         while (_drawing_thread) {
1512                 Glib::Threads::Mutex::Lock lm (request_queue_lock);
1513                 g_atomic_int_set (&drawing_thread_should_quit, 1);
1514                 request_cond.signal ();
1515         }
1516 }
1517
1518 void
1519 WaveView::drawing_thread ()
1520 {
1521         using namespace Glib::Threads;
1522
1523         WaveView const * requestor;
1524         Mutex::Lock lm (request_queue_lock);
1525         bool run = true;
1526
1527         while (run) {
1528
1529                 /* remember that we hold the lock at this point, no matter what */
1530
1531                 if (g_atomic_int_get (&drawing_thread_should_quit)) {
1532                         break;
1533                 }
1534
1535                 if (request_queue.empty()) {
1536                         request_cond.wait (request_queue_lock);
1537                 }
1538
1539                 if (request_queue.empty()) {
1540                         continue;
1541                 }
1542
1543                 /* remove the request from the queue (remember: the "request"
1544                  * is just a pointer to a WaveView object)
1545                  */
1546
1547                 requestor = *(request_queue.begin());
1548                 request_queue.erase (request_queue.begin());
1549
1550                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("start request for %1 at %2\n", requestor, g_get_monotonic_time()));
1551
1552                 boost::shared_ptr<WaveViewThreadRequest> req = requestor->current_request;
1553
1554                 if (!req) {
1555                         continue;
1556                 }
1557
1558                 /* Generate an image. Unlock the request queue lock
1559                  * while we do this, so that other things can happen
1560                  * as we do rendering.
1561                  */
1562
1563                 request_queue_lock.unlock (); /* some RAII would be good here */
1564
1565                 try {
1566                         requestor->generate_image (req, true);
1567                 } catch (...) {
1568                         req->image.clear(); /* just in case it was set before the exception, whatever it was */
1569                 }
1570
1571                 request_queue_lock.lock ();
1572
1573                 req.reset (); /* drop/delete request as appropriate */
1574         }
1575
1576         /* thread is vanishing */
1577         _drawing_thread = 0;
1578 }
1579
1580 /*-------------------------------------------------*/
1581
1582 WaveViewCache::WaveViewCache ()
1583         : image_cache_size (0)
1584         , _image_cache_threshold (100 * 1048576) /* bytes */
1585 {
1586 }
1587
1588 WaveViewCache::~WaveViewCache ()
1589 {
1590 }
1591
1592
1593 boost::shared_ptr<WaveViewCache::Entry>
1594 WaveViewCache::lookup_image (boost::shared_ptr<ARDOUR::AudioSource> src,
1595                              framepos_t start, framepos_t end,
1596                              int channel,
1597                              Coord height,
1598                              float amplitude,
1599                              Color fill_color,
1600                              double samples_per_pixel,
1601                              bool& full_coverage)
1602 {
1603         ImageCache::iterator x;
1604
1605         if ((x = cache_map.find (src)) == cache_map.end ()) {
1606                 /* nothing in the cache for this audio source at all */
1607                 return boost::shared_ptr<WaveViewCache::Entry> ();
1608         }
1609
1610         CacheLine& caches = x->second;
1611         boost::shared_ptr<Entry> best_partial;
1612         framecnt_t max_coverage = 0;
1613
1614         /* Find a suitable ImageSurface, if it exists.
1615         */
1616
1617         for (CacheLine::iterator c = caches.begin(); c != caches.end(); ++c) {
1618
1619                 boost::shared_ptr<Entry> e (*c);
1620
1621                 if (channel != e->channel
1622                     || height != e->height
1623                     || amplitude != e->amplitude
1624                     || samples_per_pixel != e->samples_per_pixel
1625                     || fill_color != e->fill_color) {
1626                         continue;
1627                 }
1628
1629                 switch (Evoral::coverage (start, end, e->start, e->end)) {
1630                 case Evoral::OverlapExternal:  /* required range is inside image range */
1631                         DEBUG_TRACE (DEBUG::WaveView, string_compose ("found image spanning %1..%2 covers %3..%4\n",
1632                                                                       e->start, e->end, start, end));
1633                         use (src, e);
1634                         full_coverage = true;
1635                         return e;
1636
1637                 case Evoral::OverlapStart: /* required range start is covered by image range */
1638                         if ((e->end - start) > max_coverage) {
1639                                 best_partial = e;
1640                                 max_coverage = e->end - start;
1641                         }
1642                         break;
1643
1644                 case Evoral::OverlapNone:
1645                 case Evoral::OverlapEnd:
1646                 case Evoral::OverlapInternal:
1647                         break;
1648                 }
1649         }
1650
1651         if (best_partial) {
1652                 DEBUG_TRACE (DEBUG::WaveView, string_compose ("found PARTIAL image spanning %1..%2 partially covers %3..%4\n",
1653                                                               best_partial->start, best_partial->end, start, end));
1654                 use (src, best_partial);
1655                 full_coverage = false;
1656                 return best_partial;
1657         }
1658
1659         return boost::shared_ptr<Entry> ();
1660 }
1661
1662 void
1663 WaveViewCache::consolidate_image_cache (boost::shared_ptr<ARDOUR::AudioSource> src,
1664                                         int channel,
1665                                         Coord height,
1666                                         float amplitude,
1667                                         Color fill_color,
1668                                         double samples_per_pixel)
1669 {
1670         list <uint32_t> deletion_list;
1671         uint32_t other_entries = 0;
1672         ImageCache::iterator x;
1673
1674         /* MUST BE CALLED FROM (SINGLE) GUI THREAD */
1675
1676         if ((x = cache_map.find (src)) == cache_map.end ()) {
1677                 return;
1678         }
1679
1680         CacheLine& caches  = x->second;
1681
1682         for (CacheLine::iterator c1 = caches.begin(); c1 != caches.end(); ) {
1683
1684                 CacheLine::iterator nxt = c1;
1685                 ++nxt;
1686
1687                 boost::shared_ptr<Entry> e1 (*c1);
1688
1689                 if (channel != e1->channel
1690                     || height != e1->height
1691                     || amplitude != e1->amplitude
1692                     || samples_per_pixel != e1->samples_per_pixel
1693                     || fill_color != e1->fill_color) {
1694
1695                         /* doesn't match current properties, ignore and move on
1696                          * to the next one.
1697                          */
1698
1699                         other_entries++;
1700                         c1 = nxt;
1701                         continue;
1702                 }
1703
1704                 /* c1 now points to a cached image entry that matches current
1705                  * properties. Check all subsequent cached imaged entries to
1706                  * see if there are others that also match but represent
1707                  * subsets of the range covered by this one.
1708                  */
1709
1710                 for (CacheLine::iterator c2 = c1; c2 != caches.end(); ) {
1711
1712                         CacheLine::iterator nxt2 = c2;
1713                         ++nxt2;
1714
1715                         boost::shared_ptr<Entry> e2 (*c2);
1716
1717                         if (e1 == e2 || channel != e2->channel
1718                             || height != e2->height
1719                             || amplitude != e2->amplitude
1720                             || samples_per_pixel != e2->samples_per_pixel
1721                             || fill_color != e2->fill_color) {
1722
1723                                 /* properties do not match, ignore for the
1724                                  * purposes of consolidation.
1725                                  */
1726                                 c2 = nxt2;
1727                                 continue;
1728                         }
1729
1730                         if (e2->start >= e1->start && e2->end <= e1->end) {
1731                                 /* c2 is fully contained by c1, so delete it */
1732                                 caches.erase (c2);
1733
1734                                 /* and re-start the whole iteration */
1735                                 nxt = caches.begin ();
1736                                 break;
1737                         }
1738
1739                         c2 = nxt2;
1740                 }
1741
1742                 c1 = nxt;
1743         }
1744 }
1745
1746 void
1747 WaveViewCache::use (boost::shared_ptr<ARDOUR::AudioSource> src, boost::shared_ptr<Entry> ce)
1748 {
1749         ce->timestamp = g_get_monotonic_time ();
1750 }
1751
1752 void
1753 WaveViewCache::add (boost::shared_ptr<ARDOUR::AudioSource> src, boost::shared_ptr<Entry> ce)
1754 {
1755         /* MUST BE CALLED FROM (SINGLE) GUI THREAD */
1756
1757         Cairo::RefPtr<Cairo::ImageSurface> img (ce->image);
1758
1759         image_cache_size += img->get_height() * img->get_width () * 4; /* 4 = bytes per FORMAT_ARGB32 pixel */
1760
1761         if (cache_full()) {
1762                 cache_flush ();
1763         }
1764
1765         ce->timestamp = g_get_monotonic_time ();
1766
1767         cache_map[src].push_back (ce);
1768 }
1769
1770 uint64_t
1771 WaveViewCache::compute_image_cache_size()
1772 {
1773         uint64_t total = 0;
1774         for (ImageCache::iterator s = cache_map.begin(); s != cache_map.end(); ++s) {
1775                 CacheLine& per_source_cache (s->second);
1776                 for (CacheLine::iterator c = per_source_cache.begin(); c != per_source_cache.end(); ++c) {
1777                         Cairo::RefPtr<Cairo::ImageSurface> img ((*c)->image);
1778                         total += img->get_height() * img->get_width() * 4; /* 4 = bytes per FORMAT_ARGB32 pixel */
1779                 }
1780         }
1781         return total;
1782 }
1783
1784 bool
1785 WaveViewCache::cache_full()
1786 {
1787         return image_cache_size > _image_cache_threshold;
1788 }
1789
1790 void
1791 WaveViewCache::cache_flush ()
1792 {
1793         /* Build a sortable list of all cache entries */
1794
1795         CacheList cache_list;
1796
1797         for (ImageCache::const_iterator cm = cache_map.begin(); cm != cache_map.end(); ++cm) {
1798                 for (CacheLine::const_iterator cl = cm->second.begin(); cl != cm->second.end(); ++cl) {
1799                         cache_list.push_back (make_pair (cm->first, *cl));
1800                 }
1801         }
1802
1803         /* sort list in LRU order */
1804         SortByTimestamp sorter;
1805         sort (cache_list.begin(), cache_list.end(), sorter);
1806
1807         while (image_cache_size > _image_cache_threshold && !cache_map.empty() && !cache_list.empty()) {
1808
1809                 ListEntry& le (cache_list.front());
1810
1811                 ImageCache::iterator x;
1812
1813                 if ((x = cache_map.find (le.first)) != cache_map.end ()) {
1814
1815                         CacheLine& cl  = x->second;
1816
1817                         for (CacheLine::iterator c = cl.begin(); c != cl.end(); ++c) {
1818
1819                                 if (*c == le.second) {
1820
1821                                         DEBUG_TRACE (DEBUG::WaveView, string_compose ("Removing cache line entry for %1\n", x->first->name()));
1822
1823                                         /* Remove this entry from this cache line */
1824                                         cl.erase (c);
1825
1826                                         if (cl.empty()) {
1827                                                 /* remove cache line from main cache: no more entries */
1828                                                 cache_map.erase (x);
1829                                         }
1830
1831                                         break;
1832                                 }
1833                         }
1834
1835                         Cairo::RefPtr<Cairo::ImageSurface> img (le.second->image);
1836                         uint64_t size = img->get_height() * img->get_width() * 4; /* 4 = bytes per FORMAT_ARGB32 pixel */
1837
1838                         if (image_cache_size > size) {
1839                                 image_cache_size -= size;
1840                         } else {
1841                                 image_cache_size = 0;
1842                         }
1843                         DEBUG_TRACE (DEBUG::WaveView, string_compose ("cache shrunk to %1\n", image_cache_size));
1844                 }
1845
1846                 /* Remove from the linear list, even if we didn't find it in
1847                  * the actual cache_mao
1848                  */
1849                 cache_list.erase (cache_list.begin());
1850         }
1851 }
1852
1853 void
1854 WaveViewCache::clear_cache ()
1855 {
1856         DEBUG_TRACE (DEBUG::WaveView, "clear cache\n");
1857         const uint64_t image_cache_threshold = _image_cache_threshold;
1858         _image_cache_threshold = 0;
1859         cache_flush ();
1860         _image_cache_threshold = image_cache_threshold;
1861 }
1862
1863 void
1864 WaveViewCache::set_image_cache_threshold (uint64_t sz)
1865 {
1866         DEBUG_TRACE (DEBUG::WaveView, string_compose ("new image cache size %1\n", sz));
1867         _image_cache_threshold = sz;
1868         cache_flush ();
1869 }