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 #include "film_viewer.h"
  28 #include "wx_util.h"
  29 #include "lib/image.h"
  30 #include "lib/dcpomatic_assert.h"
  31 #include "lib/exceptions.h"
  32 #include "lib/cross.h"
  33 #include "lib/player_video.h"
  34 #include "lib/butler.h"
  35 #include <boost/bind/bind.hpp>
  36 #include <iostream>
  37
  38 #ifdef DCPOMATIC_OSX
  39 #define GL_DO_NOT_WARN_IF_MULTI_GL_VERSION_HEADERS_INCLUDED
  40 #include <OpenGL/OpenGL.h>
  41 #include <OpenGL/gl3.h>
  42 #endif
  43
  44 #ifdef DCPOMATIC_LINUX
  45 #include <GL/glu.h>
  46 #include <GL/glext.h>
  47 #endif
  48
  49 #ifdef DCPOMATIC_WINDOWS
  50 #include <GL/glu.h>
  51 #include <GL/wglext.h>
  52 #endif
  53
  54
  55 using std::cout;
  56 using std::shared_ptr;
  57 using std::string;
  58 using boost::optional;
  59 #if BOOST_VERSION >= 106100
  60 using namespace boost::placeholders;
  61 #endif
  62
  63
  64 static void
  65 check_gl_error (char const * last)
  66 {
  67         GLenum const e = glGetError ();
  68         if (e != GL_NO_ERROR) {
  69                 throw GLError (last, e);
  70         }
  71 }
  72
  73
  74 GLVideoView::GLVideoView (FilmViewer* viewer, wxWindow *parent)
  75         : VideoView (viewer)
  76         , _context (nullptr)
  77         , _have_storage (false)
  78         , _vsync_enabled (false)
  79         , _playing (false)
  80         , _one_shot (false)
  81 {
  82         wxGLAttributes attributes;
  83         /* We don't need a depth buffer, and indeed there is apparently a bug with Windows/Intel HD 630
  84          * which puts green lines over the OpenGL display if you have a non-zero depth buffer size.
  85          * https://community.intel.com/t5/Graphics/Request-for-details-on-Intel-HD-630-green-lines-in-OpenGL-apps/m-p/1202179
  86          */
  87         attributes.PlatformDefaults().MinRGBA(8, 8, 8, 8).DoubleBuffer().Depth(0).EndList();
  88         _canvas = new wxGLCanvas (
  89                 parent, attributes, wxID_ANY, wxDefaultPosition, wxDefaultSize, wxFULL_REPAINT_ON_RESIZE
  90         );
  91         _canvas->Bind (wxEVT_PAINT, boost::bind(&GLVideoView::update, this));
  92         _canvas->Bind (wxEVT_SIZE, boost::bind(&GLVideoView::size_changed, this, _1));
  93
  94         _canvas->Bind (wxEVT_TIMER, boost::bind(&GLVideoView::check_for_butler_errors, this));
  95         _timer.reset (new wxTimer(_canvas));
  96         _timer->Start (2000);
  97 }
  98
  99
 100 void
 101 GLVideoView::size_changed (wxSizeEvent const& ev)
 102 {
 103         _canvas_size = ev.GetSize ();
 104         Sized ();
 105 }
 106
 107
 108
 109 GLVideoView::~GLVideoView ()
 110 {
 111         boost::this_thread::disable_interruption dis;
 112
 113         try {
 114                 _thread.interrupt ();
 115                 _thread.join ();
 116         } catch (...) {}
 117
 118         glDeleteTextures (1, &_texture);
 119 }
 120
 121 void
 122 GLVideoView::check_for_butler_errors ()
 123 {
 124         if (!_viewer->butler()) {
 125                 return;
 126         }
 127
 128         try {
 129                 _viewer->butler()->rethrow ();
 130         } catch (DecodeError& e) {
 131                 error_dialog (get(), e.what());
 132         } catch (dcp::ReadError& e) {
 133                 error_dialog (get(), wxString::Format(_("Could not read DCP: %s"), std_to_wx(e.what())));
 134         }
 135 }
 136
 137
 138 /** Called from the UI thread */
 139 void
 140 GLVideoView::update ()
 141 {
 142         if (!_canvas->IsShownOnScreen()) {
 143                 return;
 144         }
 145
 146         /* It appears important to do this from the GUI thread; if we do it from the GL thread
 147          * on Linux we get strange failures to create the context for any version of GL higher
 148          * than 3.2.
 149          */
 150         ensure_context ();
 151
 152 #ifdef DCPOMATIC_OSX
 153         /* macOS gives errors if we don't do this (and therefore [NSOpenGLContext setView:]) from the main thread */
 154         if (!_setup_shaders_done) {
 155                 setup_shaders ();
 156                 _setup_shaders_done = true;
 157         }
 158 #endif
 159
 160         if (!_thread.joinable()) {
 161                 _thread = boost::thread (boost::bind(&GLVideoView::thread, this));
 162         }
 163
 164         request_one_shot ();
 165
 166         rethrow ();
 167 }
 168
 169
 170 static constexpr char vertex_source[] =
 171 "#version 330 core\n"
 172 "\n"
 173 "layout (location = 0) in vec3 in_pos;\n"
 174 "layout (location = 1) in vec2 in_tex_coord;\n"
 175 "\n"
 176 "out vec2 TexCoord;\n"
 177 "\n"
 178 "void main()\n"
 179 "{\n"
 180 "       gl_Position = vec4(in_pos, 1.0);\n"
 181 "       TexCoord = in_tex_coord;\n"
 182 "}\n";
 183
 184
 185 /* Bicubic interpolation stolen from https://stackoverflow.com/questions/13501081/efficient-bicubic-filtering-code-in-glsl */
 186 static constexpr char fragment_source[] =
 187 "#version 330 core\n"
 188 "\n"
 189 "in vec2 TexCoord;\n"
 190 "\n"
 191 "uniform sampler2D texture_sampler;\n"
 192 /* type = 0: draw border
 193  * type = 1: draw XYZ image
 194  * type = 2: draw RGB image
 195  */
 196 "uniform int type = 0;\n"
 197 "uniform vec4 border_colour;\n"
 198 "uniform mat4 colour_conversion;\n"
 199 "\n"
 200 "out vec4 FragColor;\n"
 201 "\n"
 202 "vec4 cubic(float x)\n"
 203 "\n"
 204 "#define IN_GAMMA 2.2\n"
 205 "#define OUT_GAMMA 0.384615385\n"       //  1 /  2.6
 206 "#define DCI_COEFFICIENT 0.91655528\n"  // 48 / 53.37
 207 "\n"
 208 "{\n"
 209 "    float x2 = x * x;\n"
 210 "    float x3 = x2 * x;\n"
 211 "    vec4 w;\n"
 212 "    w.x =     -x3 + 3 * x2 - 3 * x + 1;\n"
 213 "    w.y =  3 * x3 - 6 * x2         + 4;\n"
 214 "    w.z = -3 * x3 + 3 * x2 + 3 * x + 1;\n"
 215 "    w.w =  x3;\n"
 216 "    return w / 6.f;\n"
 217 "}\n"
 218 "\n"
 219 "vec4 texture_bicubic(sampler2D sampler, vec2 tex_coords)\n"
 220 "{\n"
 221 "   vec2 tex_size = textureSize(sampler, 0);\n"
 222 "   vec2 inv_tex_size = 1.0 / tex_size;\n"
 223 "\n"
 224 "   tex_coords = tex_coords * tex_size - 0.5;\n"
 225 "\n"
 226 "   vec2 fxy = fract(tex_coords);\n"
 227 "   tex_coords -= fxy;\n"
 228 "\n"
 229 "   vec4 xcubic = cubic(fxy.x);\n"
 230 "   vec4 ycubic = cubic(fxy.y);\n"
 231 "\n"
 232 "   vec4 c = tex_coords.xxyy + vec2 (-0.5, +1.5).xyxy;\n"
 233 "\n"
 234 "   vec4 s = vec4(xcubic.xz + xcubic.yw, ycubic.xz + ycubic.yw);\n"
 235 "   vec4 offset = c + vec4 (xcubic.yw, ycubic.yw) / s;\n"
 236 "\n"
 237 "   offset *= inv_tex_size.xxyy;\n"
 238 "\n"
 239 "   vec4 sample0 = texture(sampler, offset.xz);\n"
 240 "   vec4 sample1 = texture(sampler, offset.yz);\n"
 241 "   vec4 sample2 = texture(sampler, offset.xw);\n"
 242 "   vec4 sample3 = texture(sampler, offset.yw);\n"
 243 "\n"
 244 "   float sx = s.x / (s.x + s.y);\n"
 245 "   float sy = s.z / (s.z + s.w);\n"
 246 "\n"
 247 "   return mix(\n"
 248 "          mix(sample3, sample2, sx), mix(sample1, sample0, sx)\n"
 249 "          , sy);\n"
 250 "}\n"
 251 "\n"
 252 "void main()\n"
 253 "{\n"
 254 "       switch (type) {\n"
 255 "               case 0:\n"
 256 "                       FragColor = border_colour;\n"
 257 "                       break;\n"
 258 "               case 1:\n"
 259 "                       FragColor = texture_bicubic(texture_sampler, TexCoord);\n"
 260 "                       FragColor.x = pow(FragColor.x, IN_GAMMA) / DCI_COEFFICIENT;\n"
 261 "                       FragColor.y = pow(FragColor.y, IN_GAMMA) / DCI_COEFFICIENT;\n"
 262 "                       FragColor.z = pow(FragColor.z, IN_GAMMA) / DCI_COEFFICIENT;\n"
 263 "                       FragColor = colour_conversion * FragColor;\n"
 264 "                       FragColor.x = pow(FragColor.x, OUT_GAMMA);\n"
 265 "                       FragColor.y = pow(FragColor.y, OUT_GAMMA);\n"
 266 "                       FragColor.z = pow(FragColor.z, OUT_GAMMA);\n"
 267 "                       break;\n"
 268 "               case 2:\n"
 269 "                       FragColor = texture_bicubic(texture_sampler, TexCoord);\n"
 270 "                       break;\n"
 271 "       }\n"
 272 "}\n";
 273
 274
 275 void
 276 GLVideoView::ensure_context ()
 277 {
 278         if (!_context) {
 279                 wxGLContextAttrs attrs;
 280                 attrs.PlatformDefaults().CoreProfile().OGLVersion(4, 1).EndList();
 281                 _context = new wxGLContext (_canvas, nullptr, &attrs);
 282                 if (!_context->IsOK()) {
 283                         throw GLError ("Making GL context", -1);
 284                 }
 285         }
 286 }
 287
 288 void
 289 GLVideoView::setup_shaders ()
 290 {
 291         DCPOMATIC_ASSERT (_canvas);
 292         DCPOMATIC_ASSERT (_context);
 293         auto r = _canvas->SetCurrent (*_context);
 294         DCPOMATIC_ASSERT (r);
 295
 296 #ifdef DCPOMATIC_WINDOWS
 297         r = glewInit();
 298         if (r != GLEW_OK) {
 299                 throw GLError(reinterpret_cast<char const*>(glewGetErrorString(r)));
 300         }
 301 #endif
 302
 303         auto get_information = [this](GLenum name) {
 304                 auto s = glGetString (name);
 305                 if (s) {
 306                         _information[name] = std::string (reinterpret_cast<char const *>(s));
 307                 }
 308         };
 309
 310         get_information (GL_VENDOR);
 311         get_information (GL_RENDERER);
 312         get_information (GL_VERSION);
 313         get_information (GL_SHADING_LANGUAGE_VERSION);
 314
 315         unsigned int indices[] = {
 316                 0, 1, 3, // texture triangle #1
 317                 1, 2, 3, // texture triangle #2
 318                 4, 5,    // border line #1
 319                 5, 6,    // border line #2
 320                 6, 7,    // border line #3
 321                 7, 4,    // border line #4
 322         };
 323
 324         glGenVertexArrays(1, &_vao);
 325         check_gl_error ("glGenVertexArrays");
 326         GLuint vbo;
 327         glGenBuffers(1, &vbo);
 328         check_gl_error ("glGenBuffers");
 329         GLuint ebo;
 330         glGenBuffers(1, &ebo);
 331         check_gl_error ("glGenBuffers");
 332
 333         glBindVertexArray(_vao);
 334         check_gl_error ("glBindVertexArray");
 335
 336         glBindBuffer(GL_ARRAY_BUFFER, vbo);
 337         check_gl_error ("glBindBuffer");
 338
 339         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo);
 340         check_gl_error ("glBindBuffer");
 341         glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
 342         check_gl_error ("glBufferData");
 343
 344         /* position attribute to vertex shader (location = 0) */
 345         glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), nullptr);
 346         glEnableVertexAttribArray(0);
 347         /* texture coord attribute to vertex shader (location = 1) */
 348         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), reinterpret_cast<void*>(3 * sizeof(float)));
 349         glEnableVertexAttribArray(1);
 350         check_gl_error ("glEnableVertexAttribArray");
 351
 352         auto compile = [](GLenum type, char const* source) -> GLuint {
 353                 auto shader = glCreateShader(type);
 354                 DCPOMATIC_ASSERT (shader);
 355                 GLchar const * src[] = { static_cast<GLchar const *>(source) };
 356                 glShaderSource(shader, 1, src, nullptr);
 357                 check_gl_error ("glShaderSource");
 358                 glCompileShader(shader);
 359                 check_gl_error ("glCompileShader");
 360                 GLint ok;
 361                 glGetShaderiv(shader, GL_COMPILE_STATUS, &ok);
 362                 if (!ok) {
 363                         GLint log_length;
 364                         glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &log_length);
 365                         string log;
 366                         if (log_length > 0) {
 367                                 char* log_char = new char[log_length];
 368                                 glGetShaderInfoLog(shader, log_length, nullptr, log_char);
 369                                 log = string(log_char);
 370                                 delete[] log_char;
 371                         }
 372                         glDeleteShader(shader);
 373                         throw GLError(String::compose("Could not compile shader (%1)", log).c_str(), -1);
 374                 }
 375                 return shader;
 376         };
 377
 378         auto vertex_shader = compile (GL_VERTEX_SHADER, vertex_source);
 379         auto fragment_shader = compile (GL_FRAGMENT_SHADER, fragment_source);
 380
 381         auto program = glCreateProgram();
 382         check_gl_error ("glCreateProgram");
 383         glAttachShader (program, vertex_shader);
 384         check_gl_error ("glAttachShader");
 385         glAttachShader (program, fragment_shader);
 386         check_gl_error ("glAttachShader");
 387         glLinkProgram (program);
 388         check_gl_error ("glLinkProgram");
 389         GLint ok;
 390         glGetProgramiv (program, GL_LINK_STATUS, &ok);
 391         if (!ok) {
 392                 GLint log_length;
 393                 glGetProgramiv(program, GL_INFO_LOG_LENGTH, &log_length);
 394                 string log;
 395                 if (log_length > 0) {
 396                         char* log_char = new char[log_length];
 397                         glGetProgramInfoLog(program, log_length, nullptr, log_char);
 398                         log = string(log_char);
 399                         delete[] log_char;
 400                 }
 401                 glDeleteProgram (program);
 402                 throw GLError(String::compose("Could not link shader (%1)", log).c_str(), -1);
 403         }
 404         glDeleteShader (vertex_shader);
 405         glDeleteShader (fragment_shader);
 406
 407         glUseProgram (program);
 408
 409         _fragment_type = glGetUniformLocation (program, "type");
 410         check_gl_error ("glGetUniformLocation");
 411         set_border_colour (program);
 412
 413         auto conversion = dcp::ColourConversion::rec709_to_xyz();
 414         boost::numeric::ublas::matrix<double> matrix = conversion.xyz_to_rgb ();
 415         GLfloat gl_matrix[] = {
 416                 static_cast<float>(matrix(0, 0)), static_cast<float>(matrix(0, 1)), static_cast<float>(matrix(0, 2)), 0.0f,
 417                 static_cast<float>(matrix(1, 0)), static_cast<float>(matrix(1, 1)), static_cast<float>(matrix(1, 2)), 0.0f,
 418                 static_cast<float>(matrix(2, 0)), static_cast<float>(matrix(2, 1)), static_cast<float>(matrix(2, 2)), 0.0f,
 419                 0.0f, 0.0f, 0.0f, 1.0f
 420                 };
 421
 422         auto colour_conversion = glGetUniformLocation (program, "colour_conversion");
 423         check_gl_error ("glGetUniformLocation");
 424         glUniformMatrix4fv (colour_conversion, 1, GL_TRUE, gl_matrix);
 425
 426         glLineWidth (2.0f);
 427 }
 428
 429
 430 void
 431 GLVideoView::set_border_colour (GLuint program)
 432 {
 433         auto uniform = glGetUniformLocation (program, "border_colour");
 434         check_gl_error ("glGetUniformLocation");
 435         auto colour = outline_content_colour ();
 436         glUniform4f (uniform, colour.Red() / 255.0f, colour.Green() / 255.0f, colour.Blue() / 255.0f, 1.0f);
 437         check_gl_error ("glUniform4f");
 438 }
 439
 440
 441 void
 442 GLVideoView::draw (Position<int>, dcp::Size)
 443 {
 444         auto pad = pad_colour();
 445         glClearColor(pad.Red() / 255.0, pad.Green() / 255.0, pad.Blue() / 255.0, 1.0);
 446         glClear (GL_COLOR_BUFFER_BIT);
 447         check_gl_error ("glClear");
 448
 449         auto const size = _canvas_size.load();
 450         int const width = size.GetWidth();
 451         int const height = size.GetHeight();
 452
 453         if (width < 64 || height < 0) {
 454                 return;
 455         }
 456
 457         glViewport (0, 0, width, height);
 458         check_gl_error ("glViewport");
 459
 460         glBindTexture(GL_TEXTURE_2D, _texture);
 461         glBindVertexArray(_vao);
 462         check_gl_error ("glBindVertexArray");
 463         glUniform1i(_fragment_type, _optimise_for_j2k ? 1 : 2);
 464         glDrawElements (GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
 465         if (_viewer->outline_content()) {
 466                 glUniform1i(_fragment_type, 1);
 467                 glDrawElements (GL_LINES, 8, GL_UNSIGNED_INT, reinterpret_cast<void*>(6 * sizeof(int)));
 468                 check_gl_error ("glDrawElements");
 469         }
 470
 471         glFlush();
 472         check_gl_error ("glFlush");
 473
 474         _canvas->SwapBuffers();
 475 }
 476
 477
 478 void
 479 GLVideoView::set_image (shared_ptr<const PlayerVideo> pv)
 480 {
 481         auto image = _optimise_for_j2k ? pv->raw_image() : pv->image(bind(&PlayerVideo::force, _1, AV_PIX_FMT_RGB24), VideoRange::FULL, false, true);
 482
 483         DCPOMATIC_ASSERT (!image->aligned());
 484
 485         /** If _optimise_for_j2k is true we render a XYZ image, doing the colourspace
 486          *  conversion, scaling and video range conversion in the GL shader.
 487          *  Othewise we render a RGB image without any shader-side processing.
 488          */
 489
 490         /* XXX: video range conversion */
 491         /* XXX: subs */
 492
 493         if (image->size() != _size) {
 494                 _have_storage = false;
 495         }
 496
 497         _size = image->size ();
 498         glPixelStorei (GL_UNPACK_ALIGNMENT, _optimise_for_j2k ? 2 : 1);
 499         check_gl_error ("glPixelStorei");
 500
 501         auto const format = _optimise_for_j2k ? GL_UNSIGNED_SHORT : GL_UNSIGNED_BYTE;
 502
 503         if (_have_storage) {
 504                 glTexSubImage2D (GL_TEXTURE_2D, 0, 0, 0, _size->width, _size->height, GL_RGB, format, image->data()[0]);
 505                 check_gl_error ("glTexSubImage2D");
 506         } else {
 507                 glTexImage2D (GL_TEXTURE_2D, 0, _optimise_for_j2k ? GL_RGBA12 : GL_RGBA8, _size->width, _size->height, 0, GL_RGB, format, image->data()[0]);
 508                 check_gl_error ("glTexImage2D");
 509
 510                 auto const canvas_size = _canvas_size.load();
 511                 int const canvas_width = canvas_size.GetWidth();
 512                 int const canvas_height = canvas_size.GetHeight();
 513
 514                 float const image_x = float(_size->width) / canvas_width;
 515                 float const image_y = float(_size->height) / canvas_height;
 516
 517                 auto x_pixels_to_gl = [canvas_width](int x) {
 518                         return (x * 2.0f / canvas_width) - 1.0f;
 519                 };
 520
 521                 auto y_pixels_to_gl = [canvas_height](int y) {
 522                         return (y * 2.0f / canvas_height) - 1.0f;
 523                 };
 524
 525                 auto inter_position = player_video().first->inter_position();
 526                 auto inter_size = player_video().first->inter_size();
 527
 528                 float const border_x1 = x_pixels_to_gl (inter_position.x) + 1.0f - image_x;
 529                 float const border_y1 = y_pixels_to_gl (inter_position.y) + 1.0f - image_y;
 530                 float const border_x2 = x_pixels_to_gl (inter_position.x + inter_size.width) + 1.0f - image_x;
 531                 float const border_y2 = y_pixels_to_gl (inter_position.y + inter_size.height) + 1.0f - image_y;
 532
 533                 float vertices[] = {
 534                         // positions                  // texture coords
 535                          image_x,   image_y,   0.0f,  1.0f, 0.0f,   // top right           (index 0)
 536                          image_x,  -image_y,   0.0f,  1.0f, 1.0f,   // bottom right        (index 1)
 537                         -image_x,  -image_y,   0.0f,  0.0f, 1.0f,   // bottom left         (index 2)
 538                         -image_x,   image_y,   0.0f,  0.0f, 0.0f,   // top left            (index 3)
 539                          border_x1, border_y1, 0.0f,  0.0f, 0.0f,   // border bottom left  (index 4)
 540                          border_x1, border_y2, 0.0f,  0.0f, 0.0f,   // border top left     (index 5)
 541                          border_x2, border_y2, 0.0f,  0.0f, 0.0f,   // border top right    (index 6)
 542                          border_x2, border_y1, 0.0f,  0.0f, 0.0f,   // border bottom right (index 7)
 543                 };
 544
 545                 /* Set the vertex shader's input data (GL_ARRAY_BUFFER) */
 546                 glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
 547                 check_gl_error ("glBufferData");
 548
 549                 _have_storage = true;
 550         }
 551
 552         glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 553         glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 554         check_gl_error ("glTexParameteri");
 555
 556         glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 557         glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 558         check_gl_error ("glTexParameterf");
 559 }
 560
 561
 562 void
 563 GLVideoView::start ()
 564 {
 565         VideoView::start ();
 566
 567         boost::mutex::scoped_lock lm (_playing_mutex);
 568         _playing = true;
 569         _thread_work_condition.notify_all ();
 570 }
 571
 572 void
 573 GLVideoView::stop ()
 574 {
 575         boost::mutex::scoped_lock lm (_playing_mutex);
 576         _playing = false;
 577 }
 578
 579
 580 void
 581 GLVideoView::thread_playing ()
 582 {
 583         if (length() != dcpomatic::DCPTime()) {
 584                 auto const next = position() + one_video_frame();
 585
 586                 if (next >= length()) {
 587                         _viewer->finished ();
 588                         return;
 589                 }
 590
 591                 get_next_frame (false);
 592                 set_image_and_draw ();
 593         }
 594
 595         while (true) {
 596                 optional<int> n = time_until_next_frame();
 597                 if (!n || *n > 5) {
 598                         break;
 599                 }
 600                 get_next_frame (true);
 601                 add_dropped ();
 602         }
 603 }
 604
 605
 606 void
 607 GLVideoView::set_image_and_draw ()
 608 {
 609         auto pv = player_video().first;
 610         if (pv) {
 611                 set_image (pv);
 612                 draw (pv->inter_position(), pv->inter_size());
 613                 _viewer->image_changed (pv);
 614         }
 615 }
 616
 617
 618 void
 619 GLVideoView::thread ()
 620 try
 621 {
 622         start_of_thread ("GLVideoView");
 623
 624 #if defined(DCPOMATIC_OSX)
 625         /* Without this we see errors like
 626          * ../src/osx/cocoa/glcanvas.mm(194): assert ""context"" failed in SwapBuffers(): should have current context [in thread 700006970000]
 627          */
 628         WXGLSetCurrentContext (_context->GetWXGLContext());
 629 #else
 630         if (!_setup_shaders_done) {
 631                 setup_shaders ();
 632                 _setup_shaders_done = true;
 633         }
 634 #endif
 635
 636 #if defined(DCPOMATIC_LINUX) && defined(DCPOMATIC_HAVE_GLX_SWAP_INTERVAL_EXT)
 637         if (_canvas->IsExtensionSupported("GLX_EXT_swap_control")) {
 638                 /* Enable vsync */
 639                 Display* dpy = wxGetX11Display();
 640                 glXSwapIntervalEXT (dpy, DefaultScreen(dpy), 1);
 641                 _vsync_enabled = true;
 642         }
 643 #endif
 644
 645 #ifdef DCPOMATIC_WINDOWS
 646         if (_canvas->IsExtensionSupported("WGL_EXT_swap_control")) {
 647                 /* Enable vsync */
 648                 PFNWGLSWAPINTERVALEXTPROC swap = (PFNWGLSWAPINTERVALEXTPROC) wglGetProcAddress("wglSwapIntervalEXT");
 649                 if (swap) {
 650                         swap (1);
 651                         _vsync_enabled = true;
 652                 }
 653         }
 654
 655 #endif
 656
 657 #ifdef DCPOMATIC_OSX
 658         /* Enable vsync */
 659         GLint swapInterval = 1;
 660         CGLSetParameter (CGLGetCurrentContext(), kCGLCPSwapInterval, &swapInterval);
 661         _vsync_enabled = true;
 662 #endif
 663
 664         glGenTextures (1, &_texture);
 665         check_gl_error ("glGenTextures");
 666         glBindTexture (GL_TEXTURE_2D, _texture);
 667         check_gl_error ("glBindTexture");
 668
 669         while (true) {
 670                 boost::mutex::scoped_lock lm (_playing_mutex);
 671                 while (!_playing && !_one_shot) {
 672                         _thread_work_condition.wait (lm);
 673                 }
 674                 lm.unlock ();
 675
 676                 if (_playing) {
 677                         thread_playing ();
 678                 } else if (_one_shot) {
 679                         _one_shot = false;
 680                         set_image_and_draw ();
 681                 }
 682
 683                 boost::this_thread::interruption_point ();
 684                 dcpomatic_sleep_milliseconds (time_until_next_frame().get_value_or(0));
 685         }
 686
 687         /* XXX: leaks _context, but that seems preferable to deleting it here
 688          * without also deleting the wxGLCanvas.
 689          */
 690 }
 691 catch (...)
 692 {
 693         store_current ();
 694 }
 695
 696
 697 VideoView::NextFrameResult
 698 GLVideoView::display_next_frame (bool non_blocking)
 699 {
 700         NextFrameResult const r = get_next_frame (non_blocking);
 701         request_one_shot ();
 702         return r;
 703 }
 704
 705
 706 void
 707 GLVideoView::request_one_shot ()
 708 {
 709         boost::mutex::scoped_lock lm (_playing_mutex);
 710         _one_shot = true;
 711         _thread_work_condition.notify_all ();
 712 }
 713