src/wx/gl_video_view.cc

   1 /*
   2     Copyright (C) 2018-2021 Carl Hetherington <cth@carlh.net>
   3
   4     This file is part of DCP-o-matic.
   5
   6     DCP-o-matic is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     DCP-o-matic is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with DCP-o-matic.  If not, see <http://www.gnu.org/licenses/>.
  18
  19 */
  20
  21
  22 #ifdef DCPOMATIC_WINDOWS
  23 #include <GL/glew.h>
  24 #endif
  25
  26 #include "gl_video_view.h"
  27
  28 /* This will only build on an new-enough wxWidgets: see the comment in gl_video_view.h */
  29 #if wxCHECK_VERSION(3,1,0)
  30
  31 #include "film_viewer.h"
  32 #include "wx_util.h"
  33 #include "lib/butler.h"
  34 #include "lib/cross.h"
  35 #include "lib/dcpomatic_assert.h"
  36 #include "lib/dcpomatic_log.h"
  37 #include "lib/exceptions.h"
  38 #include "lib/image.h"
  39 #include "lib/player_video.h"
  40 #include <boost/bind/bind.hpp>
  41 #include <iostream>
  42
  43 #ifdef DCPOMATIC_OSX
  44 #define GL_DO_NOT_WARN_IF_MULTI_GL_VERSION_HEADERS_INCLUDED
  45 #include <OpenGL/OpenGL.h>
  46 #include <OpenGL/gl3.h>
  47 #endif
  48
  49 #ifdef DCPOMATIC_LINUX
  50 #include <GL/glu.h>
  51 #include <GL/glext.h>
  52 #endif
  53
  54 #ifdef DCPOMATIC_WINDOWS
  55 #include <GL/glu.h>
  56 #include <GL/wglext.h>
  57 #endif
  58
  59
  60 using std::cout;
  61 using std::shared_ptr;
  62 using std::string;
  63 using boost::optional;
  64 #if BOOST_VERSION >= 106100
  65 using namespace boost::placeholders;
  66 #endif
  67
  68
  69 static void
  70 check_gl_error (char const * last)
  71 {
  72         GLenum const e = glGetError ();
  73         if (e != GL_NO_ERROR) {
  74                 throw GLError (last, e);
  75         }
  76 }
  77
  78
  79 GLVideoView::GLVideoView (FilmViewer* viewer, wxWindow *parent)
  80         : VideoView (viewer)
  81         , _context (nullptr)
  82         , _vsync_enabled (false)
  83         , _playing (false)
  84         , _one_shot (false)
  85 {
  86         wxGLAttributes attributes;
  87         /* We don't need a depth buffer, and indeed there is apparently a bug with Windows/Intel HD 630
  88          * which puts green lines over the OpenGL display if you have a non-zero depth buffer size.
  89          * https://community.intel.com/t5/Graphics/Request-for-details-on-Intel-HD-630-green-lines-in-OpenGL-apps/m-p/1202179
  90          */
  91         attributes.PlatformDefaults().MinRGBA(8, 8, 8, 8).DoubleBuffer().Depth(0).EndList();
  92         _canvas = new wxGLCanvas (
  93                 parent, attributes, wxID_ANY, wxDefaultPosition, wxDefaultSize, wxFULL_REPAINT_ON_RESIZE
  94         );
  95         _canvas->Bind (wxEVT_PAINT, boost::bind(&GLVideoView::update, this));
  96         _canvas->Bind (wxEVT_SIZE, boost::bind(&GLVideoView::size_changed, this, _1));
  97
  98         _canvas->Bind (wxEVT_TIMER, boost::bind(&GLVideoView::check_for_butler_errors, this));
  99         _timer.reset (new wxTimer(_canvas));
 100         _timer->Start (2000);
 101 }
 102
 103
 104 void
 105 GLVideoView::size_changed (wxSizeEvent const& ev)
 106 {
 107         auto const scale = _canvas->GetDPIScaleFactor();
 108         int const width = std::round(ev.GetSize().GetWidth() * scale);
 109         int const height = std::round(ev.GetSize().GetHeight() * scale);
 110         _canvas_size = { width, height };
 111         LOG_GENERAL("GLVideoView canvas size changed to %1x%2", width, height);
 112         Sized ();
 113 }
 114
 115
 116 GLVideoView::~GLVideoView ()
 117 {
 118         boost::this_thread::disable_interruption dis;
 119
 120         try {
 121                 _thread.interrupt ();
 122                 _thread.join ();
 123         } catch (...) {}
 124 }
 125
 126 void
 127 GLVideoView::check_for_butler_errors ()
 128 {
 129         if (!_viewer->butler()) {
 130                 return;
 131         }
 132
 133         try {
 134                 _viewer->butler()->rethrow ();
 135         } catch (DecodeError& e) {
 136                 error_dialog (get(), e.what());
 137         } catch (dcp::ReadError& e) {
 138                 error_dialog (get(), wxString::Format(_("Could not read DCP: %s"), std_to_wx(e.what())));
 139         }
 140 }
 141
 142
 143 /** Called from the UI thread */
 144 void
 145 GLVideoView::update ()
 146 {
 147         if (!_canvas->IsShownOnScreen()) {
 148                 return;
 149         }
 150
 151         /* It appears important to do this from the GUI thread; if we do it from the GL thread
 152          * on Linux we get strange failures to create the context for any version of GL higher
 153          * than 3.2.
 154          */
 155         ensure_context ();
 156
 157 #ifdef DCPOMATIC_OSX
 158         /* macOS gives errors if we don't do this (and therefore [NSOpenGLContext setView:]) from the main thread */
 159         if (!_setup_shaders_done) {
 160                 setup_shaders ();
 161                 _setup_shaders_done = true;
 162         }
 163 #endif
 164
 165         if (!_thread.joinable()) {
 166                 _thread = boost::thread (boost::bind(&GLVideoView::thread, this));
 167         }
 168
 169         request_one_shot ();
 170
 171         rethrow ();
 172 }
 173
 174
 175 static constexpr char vertex_source[] =
 176 "#version 330 core\n"
 177 "\n"
 178 "layout (location = 0) in vec3 in_pos;\n"
 179 "layout (location = 1) in vec2 in_tex_coord;\n"
 180 "\n"
 181 "out vec2 TexCoord;\n"
 182 "\n"
 183 "void main()\n"
 184 "{\n"
 185 "       gl_Position = vec4(in_pos, 1.0);\n"
 186 "       TexCoord = in_tex_coord;\n"
 187 "}\n";
 188
 189
 190 /* Bicubic interpolation stolen from https://stackoverflow.com/questions/13501081/efficient-bicubic-filtering-code-in-glsl */
 191 static constexpr char fragment_source[] =
 192 "#version 330 core\n"
 193 "\n"
 194 "in vec2 TexCoord;\n"
 195 "\n"
 196 "uniform sampler2D texture_sampler;\n"
 197 /* type = 0: draw outline content rectangle
 198  * type = 1: draw XYZ image
 199  * type = 2: draw RGB image
 200  * See FragmentType enum below.
 201  */
 202 "uniform int type = 0;\n"
 203 "uniform vec4 outline_content_colour;\n"
 204 "uniform mat4 colour_conversion;\n"
 205 "\n"
 206 "out vec4 FragColor;\n"
 207 "\n"
 208 "vec4 cubic(float x)\n"
 209 "\n"
 210 "#define IN_GAMMA 2.2\n"
 211 "#define OUT_GAMMA 0.384615385\n"       //  1 /  2.6
 212 "#define DCI_COEFFICIENT 0.91655528\n"  // 48 / 53.37
 213 "\n"
 214 "{\n"
 215 "    float x2 = x * x;\n"
 216 "    float x3 = x2 * x;\n"
 217 "    vec4 w;\n"
 218 "    w.x =     -x3 + 3 * x2 - 3 * x + 1;\n"
 219 "    w.y =  3 * x3 - 6 * x2         + 4;\n"
 220 "    w.z = -3 * x3 + 3 * x2 + 3 * x + 1;\n"
 221 "    w.w =  x3;\n"
 222 "    return w / 6.f;\n"
 223 "}\n"
 224 "\n"
 225 "vec4 texture_bicubic(sampler2D sampler, vec2 tex_coords)\n"
 226 "{\n"
 227 "   vec2 tex_size = textureSize(sampler, 0);\n"
 228 "   vec2 inv_tex_size = 1.0 / tex_size;\n"
 229 "\n"
 230 "   tex_coords = tex_coords * tex_size - 0.5;\n"
 231 "\n"
 232 "   vec2 fxy = fract(tex_coords);\n"
 233 "   tex_coords -= fxy;\n"
 234 "\n"
 235 "   vec4 xcubic = cubic(fxy.x);\n"
 236 "   vec4 ycubic = cubic(fxy.y);\n"
 237 "\n"
 238 "   vec4 c = tex_coords.xxyy + vec2 (-0.5, +1.5).xyxy;\n"
 239 "\n"
 240 "   vec4 s = vec4(xcubic.xz + xcubic.yw, ycubic.xz + ycubic.yw);\n"
 241 "   vec4 offset = c + vec4 (xcubic.yw, ycubic.yw) / s;\n"
 242 "\n"
 243 "   offset *= inv_tex_size.xxyy;\n"
 244 "\n"
 245 "   vec4 sample0 = texture(sampler, offset.xz);\n"
 246 "   vec4 sample1 = texture(sampler, offset.yz);\n"
 247 "   vec4 sample2 = texture(sampler, offset.xw);\n"
 248 "   vec4 sample3 = texture(sampler, offset.yw);\n"
 249 "\n"
 250 "   float sx = s.x / (s.x + s.y);\n"
 251 "   float sy = s.z / (s.z + s.w);\n"
 252 "\n"
 253 "   return mix(\n"
 254 "          mix(sample3, sample2, sx), mix(sample1, sample0, sx)\n"
 255 "          , sy);\n"
 256 "}\n"
 257 "\n"
 258 "void main()\n"
 259 "{\n"
 260 "       switch (type) {\n"
 261 "               case 0:\n"
 262 "                       FragColor = outline_content_colour;\n"
 263 "                       break;\n"
 264 "               case 1:\n"
 265 "                       FragColor = texture_bicubic(texture_sampler, TexCoord);\n"
 266 "                       FragColor.x = pow(FragColor.x, IN_GAMMA) / DCI_COEFFICIENT;\n"
 267 "                       FragColor.y = pow(FragColor.y, IN_GAMMA) / DCI_COEFFICIENT;\n"
 268 "                       FragColor.z = pow(FragColor.z, IN_GAMMA) / DCI_COEFFICIENT;\n"
 269 "                       FragColor = colour_conversion * FragColor;\n"
 270 "                       FragColor.x = pow(FragColor.x, OUT_GAMMA);\n"
 271 "                       FragColor.y = pow(FragColor.y, OUT_GAMMA);\n"
 272 "                       FragColor.z = pow(FragColor.z, OUT_GAMMA);\n"
 273 "                       break;\n"
 274 "               case 2:\n"
 275 "                       FragColor = texture_bicubic(texture_sampler, TexCoord);\n"
 276 "                       break;\n"
 277 "       }\n"
 278 "}\n";
 279
 280
 281 enum class FragmentType
 282 {
 283         OUTLINE_CONTENT = 0,
 284         XYZ_IMAGE = 1,
 285         RGB_IMAGE = 2,
 286 };
 287
 288
 289 void
 290 GLVideoView::ensure_context ()
 291 {
 292         if (!_context) {
 293                 wxGLContextAttrs attrs;
 294                 attrs.PlatformDefaults().CoreProfile().OGLVersion(4, 1).EndList();
 295                 _context = new wxGLContext (_canvas, nullptr, &attrs);
 296                 if (!_context->IsOK()) {
 297                         throw GLError ("Making GL context", -1);
 298                 }
 299         }
 300 }
 301
 302
 303 /* Offset and number of indices for the things in the indices array below */
 304 static constexpr int indices_video_texture_offset = 0;
 305 static constexpr int indices_video_texture_number = 6;
 306 static constexpr int indices_subtitle_texture_offset = indices_video_texture_offset + indices_video_texture_number;
 307 static constexpr int indices_subtitle_texture_number = 6;
 308 static constexpr int indices_outline_content_offset = indices_subtitle_texture_offset + indices_subtitle_texture_number;
 309 static constexpr int indices_outline_content_number = 8;
 310
 311 static constexpr unsigned int indices[] = {
 312         0, 1, 3, // video texture triangle #1
 313         1, 2, 3, // video texture triangle #2
 314         4, 5, 7, // subtitle texture triangle #1
 315         5, 6, 7, // subtitle texture triangle #2
 316         8, 9,    // outline content line #1
 317         9, 10,   // outline content line #2
 318         10, 11,  // outline content line #3
 319         11, 8,   // outline content line #4
 320 };
 321
 322 /* Offsets of things in the GL_ARRAY_BUFFER */
 323 static constexpr int array_buffer_video_offset = 0;
 324 static constexpr int array_buffer_subtitle_offset = array_buffer_video_offset + 4 * 5 * sizeof(float);
 325 static constexpr int array_buffer_outline_content_offset = array_buffer_subtitle_offset + 4 * 5 * sizeof(float);
 326
 327
 328 void
 329 GLVideoView::setup_shaders ()
 330 {
 331         DCPOMATIC_ASSERT (_canvas);
 332         DCPOMATIC_ASSERT (_context);
 333         auto r = _canvas->SetCurrent (*_context);
 334         DCPOMATIC_ASSERT (r);
 335
 336 #ifdef DCPOMATIC_WINDOWS
 337         r = glewInit();
 338         if (r != GLEW_OK) {
 339                 throw GLError(reinterpret_cast<char const*>(glewGetErrorString(r)));
 340         }
 341 #endif
 342
 343         auto get_information = [this](GLenum name) {
 344                 auto s = glGetString (name);
 345                 if (s) {
 346                         _information[name] = std::string (reinterpret_cast<char const *>(s));
 347                 }
 348         };
 349
 350         get_information (GL_VENDOR);
 351         get_information (GL_RENDERER);
 352         get_information (GL_VERSION);
 353         get_information (GL_SHADING_LANGUAGE_VERSION);
 354
 355         glGenVertexArrays(1, &_vao);
 356         check_gl_error ("glGenVertexArrays");
 357         GLuint vbo;
 358         glGenBuffers(1, &vbo);
 359         check_gl_error ("glGenBuffers");
 360         GLuint ebo;
 361         glGenBuffers(1, &ebo);
 362         check_gl_error ("glGenBuffers");
 363
 364         glBindVertexArray(_vao);
 365         check_gl_error ("glBindVertexArray");
 366
 367         glBindBuffer(GL_ARRAY_BUFFER, vbo);
 368         check_gl_error ("glBindBuffer");
 369
 370         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo);
 371         check_gl_error ("glBindBuffer");
 372         glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
 373         check_gl_error ("glBufferData");
 374
 375         /* position attribute to vertex shader (location = 0) */
 376         glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), nullptr);
 377         glEnableVertexAttribArray(0);
 378         /* texture coord attribute to vertex shader (location = 1) */
 379         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), reinterpret_cast<void*>(3 * sizeof(float)));
 380         glEnableVertexAttribArray(1);
 381         check_gl_error ("glEnableVertexAttribArray");
 382
 383         auto compile = [](GLenum type, char const* source) -> GLuint {
 384                 auto shader = glCreateShader(type);
 385                 DCPOMATIC_ASSERT (shader);
 386                 GLchar const * src[] = { static_cast<GLchar const *>(source) };
 387                 glShaderSource(shader, 1, src, nullptr);
 388                 check_gl_error ("glShaderSource");
 389                 glCompileShader(shader);
 390                 check_gl_error ("glCompileShader");
 391                 GLint ok;
 392                 glGetShaderiv(shader, GL_COMPILE_STATUS, &ok);
 393                 if (!ok) {
 394                         GLint log_length;
 395                         glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &log_length);
 396                         string log;
 397                         if (log_length > 0) {
 398                                 char* log_char = new char[log_length];
 399                                 glGetShaderInfoLog(shader, log_length, nullptr, log_char);
 400                                 log = string(log_char);
 401                                 delete[] log_char;
 402                         }
 403                         glDeleteShader(shader);
 404                         throw GLError(String::compose("Could not compile shader (%1)", log).c_str(), -1);
 405                 }
 406                 return shader;
 407         };
 408
 409         auto vertex_shader = compile (GL_VERTEX_SHADER, vertex_source);
 410         auto fragment_shader = compile (GL_FRAGMENT_SHADER, fragment_source);
 411
 412         auto program = glCreateProgram();
 413         check_gl_error ("glCreateProgram");
 414         glAttachShader (program, vertex_shader);
 415         check_gl_error ("glAttachShader");
 416         glAttachShader (program, fragment_shader);
 417         check_gl_error ("glAttachShader");
 418         glLinkProgram (program);
 419         check_gl_error ("glLinkProgram");
 420         GLint ok;
 421         glGetProgramiv (program, GL_LINK_STATUS, &ok);
 422         if (!ok) {
 423                 GLint log_length;
 424                 glGetProgramiv(program, GL_INFO_LOG_LENGTH, &log_length);
 425                 string log;
 426                 if (log_length > 0) {
 427                         char* log_char = new char[log_length];
 428                         glGetProgramInfoLog(program, log_length, nullptr, log_char);
 429                         log = string(log_char);
 430                         delete[] log_char;
 431                 }
 432                 glDeleteProgram (program);
 433                 throw GLError(String::compose("Could not link shader (%1)", log).c_str(), -1);
 434         }
 435         glDeleteShader (vertex_shader);
 436         glDeleteShader (fragment_shader);
 437
 438         glUseProgram (program);
 439
 440         _fragment_type = glGetUniformLocation (program, "type");
 441         check_gl_error ("glGetUniformLocation");
 442         set_outline_content_colour (program);
 443
 444         auto conversion = dcp::ColourConversion::rec709_to_xyz();
 445         boost::numeric::ublas::matrix<double> matrix = conversion.xyz_to_rgb ();
 446         GLfloat gl_matrix[] = {
 447                 static_cast<float>(matrix(0, 0)), static_cast<float>(matrix(0, 1)), static_cast<float>(matrix(0, 2)), 0.0f,
 448                 static_cast<float>(matrix(1, 0)), static_cast<float>(matrix(1, 1)), static_cast<float>(matrix(1, 2)), 0.0f,
 449                 static_cast<float>(matrix(2, 0)), static_cast<float>(matrix(2, 1)), static_cast<float>(matrix(2, 2)), 0.0f,
 450                 0.0f, 0.0f, 0.0f, 1.0f
 451                 };
 452
 453         auto colour_conversion = glGetUniformLocation (program, "colour_conversion");
 454         check_gl_error ("glGetUniformLocation");
 455         glUniformMatrix4fv (colour_conversion, 1, GL_TRUE, gl_matrix);
 456
 457         glLineWidth (1.0f);
 458         check_gl_error ("glLineWidth");
 459         glEnable (GL_BLEND);
 460         check_gl_error ("glEnable");
 461         glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 462         check_gl_error ("glBlendFunc");
 463
 464         /* Reserve space for the GL_ARRAY_BUFFER */
 465         glBufferData(GL_ARRAY_BUFFER, 12 * 5 * sizeof(float), nullptr, GL_STATIC_DRAW);
 466         check_gl_error ("glBufferData");
 467 }
 468
 469
 470 void
 471 GLVideoView::set_outline_content_colour (GLuint program)
 472 {
 473         auto uniform = glGetUniformLocation (program, "outline_content_colour");
 474         check_gl_error ("glGetUniformLocation");
 475         auto colour = outline_content_colour ();
 476         glUniform4f (uniform, colour.Red() / 255.0f, colour.Green() / 255.0f, colour.Blue() / 255.0f, 1.0f);
 477         check_gl_error ("glUniform4f");
 478 }
 479
 480
 481 void
 482 GLVideoView::draw ()
 483 {
 484         auto pad = pad_colour();
 485         glClearColor(pad.Red() / 255.0, pad.Green() / 255.0, pad.Blue() / 255.0, 1.0);
 486         glClear (GL_COLOR_BUFFER_BIT);
 487         check_gl_error ("glClear");
 488
 489         auto const size = _canvas_size.load();
 490         int const width = size.GetWidth();
 491         int const height = size.GetHeight();
 492
 493         if (width < 64 || height < 0) {
 494                 return;
 495         }
 496
 497         glViewport (0, 0, width, height);
 498         check_gl_error ("glViewport");
 499
 500         glBindVertexArray(_vao);
 501         check_gl_error ("glBindVertexArray");
 502         glUniform1i(_fragment_type, static_cast<GLint>(_optimise_for_j2k ? FragmentType::XYZ_IMAGE : FragmentType::RGB_IMAGE));
 503         _video_texture->bind();
 504         glDrawElements (GL_TRIANGLES, indices_video_texture_number, GL_UNSIGNED_INT, reinterpret_cast<void*>(indices_video_texture_offset * sizeof(int)));
 505         if (_have_subtitle_to_render) {
 506                 glUniform1i(_fragment_type, static_cast<GLint>(FragmentType::RGB_IMAGE));
 507                 _subtitle_texture->bind();
 508                 glDrawElements (GL_TRIANGLES, indices_subtitle_texture_number, GL_UNSIGNED_INT, reinterpret_cast<void*>(indices_subtitle_texture_offset * sizeof(int)));
 509         }
 510         if (_viewer->outline_content()) {
 511                 glUniform1i(_fragment_type, static_cast<GLint>(FragmentType::OUTLINE_CONTENT));
 512                 glDrawElements (GL_LINES, indices_outline_content_number, GL_UNSIGNED_INT, reinterpret_cast<void*>(indices_outline_content_offset * sizeof(int)));
 513                 check_gl_error ("glDrawElements");
 514         }
 515
 516         glFlush();
 517         check_gl_error ("glFlush");
 518
 519         _canvas->SwapBuffers();
 520 }
 521
 522
 523 void
 524 GLVideoView::set_image (shared_ptr<const PlayerVideo> pv)
 525 {
 526         shared_ptr<const Image> video = _optimise_for_j2k ? pv->raw_image() : pv->image(boost::bind(&PlayerVideo::force, AV_PIX_FMT_RGB24), VideoRange::FULL, true);
 527
 528         /* Only the player's black frames should be aligned at this stage, so this should
 529          * almost always have no work to do.
 530          */
 531         video = Image::ensure_alignment (video, Image::Alignment::COMPACT);
 532
 533         /** If _optimise_for_j2k is true we render a XYZ image, doing the colourspace
 534          *  conversion, scaling and video range conversion in the GL shader.
 535          *  Otherwise we render a RGB image without any shader-side processing.
 536          */
 537
 538         /* XXX: video range conversion */
 539
 540         _video_texture->set (video);
 541
 542         auto const text = pv->text();
 543         _have_subtitle_to_render = static_cast<bool>(text) && _optimise_for_j2k;
 544         if (_have_subtitle_to_render) {
 545                 /* opt: only do this if it's a new subtitle? */
 546                 DCPOMATIC_ASSERT (text->image->alignment() == Image::Alignment::COMPACT);
 547                 _subtitle_texture->set (text->image);
 548         }
 549
 550
 551         auto const canvas_size = _canvas_size.load();
 552         int const canvas_width = canvas_size.GetWidth();
 553         int const canvas_height = canvas_size.GetHeight();
 554         auto const inter_position = player_video().first->inter_position();
 555         auto const inter_size = player_video().first->inter_size();
 556         auto const out_size = player_video().first->out_size();
 557
 558         auto x_offset = std::max(0, (canvas_width - out_size.width) / 2);
 559         auto y_offset = std::max(0, (canvas_height - out_size.height) / 2);
 560
 561         _last_canvas_size.set_next (canvas_size);
 562         _last_video_size.set_next (video->size());
 563         _last_inter_position.set_next (inter_position);
 564         _last_inter_size.set_next (inter_size);
 565         _last_out_size.set_next (out_size);
 566
 567         class Rectangle
 568         {
 569         public:
 570                 Rectangle (wxSize canvas_size, float x, float y, dcp::Size size)
 571                         : _canvas_size (canvas_size)
 572                 {
 573                         auto const x1 = x_pixels_to_gl(x);
 574                         auto const y1 = y_pixels_to_gl(y);
 575                         auto const x2 = x_pixels_to_gl(x + size.width);
 576                         auto const y2 = y_pixels_to_gl(y + size.height);
 577
 578                         /* The texture coordinates here have to account for the fact that when we put images into the texture OpenGL
 579                          * expected us to start at the lower left but we actually started at the top left.  So although the
 580                          * top of the texture is at 1.0 we pretend it's the other way round.
 581                          */
 582
 583                         // bottom right
 584                         _vertices[0] = x2;
 585                         _vertices[1] = y2;
 586                         _vertices[2] = 0.0f;
 587                         _vertices[3] = 1.0f;
 588                         _vertices[4] = 1.0f;
 589
 590                         // top right
 591                         _vertices[5] = x2;
 592                         _vertices[6] = y1;
 593                         _vertices[7] = 0.0f;
 594                         _vertices[8] = 1.0f;
 595                         _vertices[9] = 0.0f;
 596
 597                         // top left
 598                         _vertices[10] = x1;
 599                         _vertices[11] = y1;
 600                         _vertices[12] = 0.0f;
 601                         _vertices[13] = 0.0f;
 602                         _vertices[14] = 0.0f;
 603
 604                         // bottom left
 605                         _vertices[15] = x1;
 606                         _vertices[16] = y2;
 607                         _vertices[17] = 0.0f;
 608                         _vertices[18] = 0.0f;
 609                         _vertices[19] = 1.0f;
 610                 }
 611
 612                 float const * vertices () const {
 613                         return _vertices;
 614                 }
 615
 616                 int const size () const {
 617                         return sizeof(_vertices);
 618                 }
 619
 620         private:
 621                 /* @param x x position in pixels where 0 is left and canvas_width is right on screen */
 622                 float x_pixels_to_gl(int x) const {
 623                         return (x * 2.0f / _canvas_size.GetWidth()) - 1.0f;
 624                 }
 625
 626                 /* @param y y position in pixels where 0 is top and canvas_height is bottom on screen */
 627                 float y_pixels_to_gl(int y) const {
 628                         return 1.0f - (y * 2.0f / _canvas_size.GetHeight());
 629                 }
 630
 631                 wxSize _canvas_size;
 632                 float _vertices[20];
 633         };
 634
 635         if (_last_canvas_size.changed() || _last_inter_position.changed() || _last_inter_size.changed() || _last_out_size.changed()) {
 636
 637                 const auto video = _optimise_for_j2k ?
 638                         Rectangle(canvas_size, inter_position.x + x_offset, inter_position.y + y_offset, inter_size)
 639                         : Rectangle(canvas_size, x_offset, y_offset, out_size);
 640
 641                 glBufferSubData (GL_ARRAY_BUFFER, array_buffer_video_offset, video.size(), video.vertices());
 642                 check_gl_error ("glBufferSubData (video)");
 643
 644                 const auto outline_content = Rectangle(canvas_size, inter_position.x + x_offset, inter_position.y + y_offset, inter_size);
 645                 glBufferSubData (GL_ARRAY_BUFFER, array_buffer_outline_content_offset, outline_content.size(), outline_content.vertices());
 646                 check_gl_error ("glBufferSubData (outline_content)");
 647         }
 648
 649         if (_have_subtitle_to_render) {
 650                 const auto subtitle = Rectangle(canvas_size, inter_position.x + x_offset + text->position.x, inter_position.y + y_offset + text->position.y, text->image->size());
 651                 glBufferSubData (GL_ARRAY_BUFFER, array_buffer_subtitle_offset, subtitle.size(), subtitle.vertices());
 652                 check_gl_error ("glBufferSubData (subtitle)");
 653         }
 654
 655         /* opt: where should these go? */
 656
 657         glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 658         glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 659         check_gl_error ("glTexParameteri");
 660
 661         glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 662         glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 663         check_gl_error ("glTexParameterf");
 664 }
 665
 666
 667 void
 668 GLVideoView::start ()
 669 {
 670         VideoView::start ();
 671
 672         boost::mutex::scoped_lock lm (_playing_mutex);
 673         _playing = true;
 674         _thread_work_condition.notify_all ();
 675 }
 676
 677 void
 678 GLVideoView::stop ()
 679 {
 680         boost::mutex::scoped_lock lm (_playing_mutex);
 681         _playing = false;
 682 }
 683
 684
 685 void
 686 GLVideoView::thread_playing ()
 687 {
 688         if (length() != dcpomatic::DCPTime()) {
 689                 auto const next = position() + one_video_frame();
 690
 691                 if (next >= length()) {
 692                         _viewer->finished ();
 693                         return;
 694                 }
 695
 696                 get_next_frame (false);
 697                 set_image_and_draw ();
 698         }
 699
 700         while (true) {
 701                 optional<int> n = time_until_next_frame();
 702                 if (!n || *n > 5) {
 703                         break;
 704                 }
 705                 get_next_frame (true);
 706                 add_dropped ();
 707         }
 708 }
 709
 710
 711 void
 712 GLVideoView::set_image_and_draw ()
 713 {
 714         auto pv = player_video().first;
 715         if (pv) {
 716                 set_image (pv);
 717         }
 718
 719         draw ();
 720
 721         if (pv) {
 722                 _viewer->image_changed (pv);
 723         }
 724 }
 725
 726
 727 void
 728 GLVideoView::thread ()
 729 try
 730 {
 731         start_of_thread ("GLVideoView");
 732
 733 #if defined(DCPOMATIC_OSX)
 734         /* Without this we see errors like
 735          * ../src/osx/cocoa/glcanvas.mm(194): assert ""context"" failed in SwapBuffers(): should have current context [in thread 700006970000]
 736          */
 737         WXGLSetCurrentContext (_context->GetWXGLContext());
 738 #else
 739         if (!_setup_shaders_done) {
 740                 setup_shaders ();
 741                 _setup_shaders_done = true;
 742         }
 743 #endif
 744
 745 #if defined(DCPOMATIC_LINUX) && defined(DCPOMATIC_HAVE_GLX_SWAP_INTERVAL_EXT)
 746         if (_canvas->IsExtensionSupported("GLX_EXT_swap_control")) {
 747                 /* Enable vsync */
 748                 Display* dpy = wxGetX11Display();
 749                 glXSwapIntervalEXT (dpy, DefaultScreen(dpy), 1);
 750                 _vsync_enabled = true;
 751         }
 752 #endif
 753
 754 #ifdef DCPOMATIC_WINDOWS
 755         if (_canvas->IsExtensionSupported("WGL_EXT_swap_control")) {
 756                 /* Enable vsync */
 757                 PFNWGLSWAPINTERVALEXTPROC swap = (PFNWGLSWAPINTERVALEXTPROC) wglGetProcAddress("wglSwapIntervalEXT");
 758                 if (swap) {
 759                         swap (1);
 760                         _vsync_enabled = true;
 761                 }
 762         }
 763
 764 #endif
 765
 766 #ifdef DCPOMATIC_OSX
 767         /* Enable vsync */
 768         GLint swapInterval = 1;
 769         CGLSetParameter (CGLGetCurrentContext(), kCGLCPSwapInterval, &swapInterval);
 770         _vsync_enabled = true;
 771 #endif
 772
 773         _video_texture.reset(new Texture(_optimise_for_j2k ? 2 : 1));
 774         _subtitle_texture.reset(new Texture(1));
 775
 776         while (true) {
 777                 boost::mutex::scoped_lock lm (_playing_mutex);
 778                 while (!_playing && !_one_shot) {
 779                         _thread_work_condition.wait (lm);
 780                 }
 781                 lm.unlock ();
 782
 783                 if (_playing) {
 784                         thread_playing ();
 785                 } else if (_one_shot) {
 786                         _one_shot = false;
 787                         set_image_and_draw ();
 788                 }
 789
 790                 boost::this_thread::interruption_point ();
 791                 dcpomatic_sleep_milliseconds (time_until_next_frame().get_value_or(0));
 792         }
 793
 794         /* XXX: leaks _context, but that seems preferable to deleting it here
 795          * without also deleting the wxGLCanvas.
 796          */
 797 }
 798 catch (...)
 799 {
 800         store_current ();
 801 }
 802
 803
 804 VideoView::NextFrameResult
 805 GLVideoView::display_next_frame (bool non_blocking)
 806 {
 807         NextFrameResult const r = get_next_frame (non_blocking);
 808         request_one_shot ();
 809         return r;
 810 }
 811
 812
 813 void
 814 GLVideoView::request_one_shot ()
 815 {
 816         boost::mutex::scoped_lock lm (_playing_mutex);
 817         _one_shot = true;
 818         _thread_work_condition.notify_all ();
 819 }
 820
 821
 822 Texture::Texture (GLint unpack_alignment)
 823         : _unpack_alignment (unpack_alignment)
 824 {
 825         glGenTextures (1, &_name);
 826         check_gl_error ("glGenTextures");
 827 }
 828
 829
 830 Texture::~Texture ()
 831 {
 832         glDeleteTextures (1, &_name);
 833 }
 834
 835
 836 void
 837 Texture::bind ()
 838 {
 839         glBindTexture(GL_TEXTURE_2D, _name);
 840         check_gl_error ("glBindTexture");
 841 }
 842
 843
 844 void
 845 Texture::set (shared_ptr<const Image> image)
 846 {
 847         auto const create = !_size || image->size() != _size;
 848         _size = image->size();
 849
 850         glPixelStorei (GL_UNPACK_ALIGNMENT, _unpack_alignment);
 851         check_gl_error ("glPixelStorei");
 852
 853         DCPOMATIC_ASSERT (image->alignment() == Image::Alignment::COMPACT);
 854
 855         GLint internal_format;
 856         GLenum format;
 857         GLenum type;
 858
 859         switch (image->pixel_format()) {
 860         case AV_PIX_FMT_BGRA:
 861                 internal_format = GL_RGBA8;
 862                 format = GL_BGRA;
 863                 type = GL_UNSIGNED_BYTE;
 864                 break;
 865         case AV_PIX_FMT_RGBA:
 866                 internal_format = GL_RGBA8;
 867                 format = GL_RGBA;
 868                 type = GL_UNSIGNED_BYTE;
 869                 break;
 870         case AV_PIX_FMT_RGB24:
 871                 internal_format = GL_RGBA8;
 872                 format = GL_RGB;
 873                 type = GL_UNSIGNED_BYTE;
 874                 break;
 875         case AV_PIX_FMT_XYZ12:
 876                 internal_format = GL_RGBA12;
 877                 format = GL_RGB;
 878                 type = GL_UNSIGNED_SHORT;
 879                 break;
 880         default:
 881                 throw PixelFormatError ("Texture::set", image->pixel_format());
 882         }
 883
 884         bind ();
 885
 886         if (create) {
 887                 glTexImage2D (GL_TEXTURE_2D, 0, internal_format, _size->width, _size->height, 0, format, type, image->data()[0]);
 888                 check_gl_error ("glTexImage2D");
 889         } else {
 890                 glTexSubImage2D (GL_TEXTURE_2D, 0, 0, 0, _size->width, _size->height, format, type, image->data()[0]);
 891                 check_gl_error ("glTexSubImage2D");
 892         }
 893 }
 894
 895 #endif