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::bind;
  64 using boost::optional;
  65 #if BOOST_VERSION >= 106100
  66 using namespace boost::placeholders;
  67 #endif
  68
  69
  70 static void
  71 check_gl_error (char const * last)
  72 {
  73         GLenum const e = glGetError ();
  74         if (e != GL_NO_ERROR) {
  75                 throw GLError (last, e);
  76         }
  77 }
  78
  79
  80 GLVideoView::GLVideoView (FilmViewer* viewer, wxWindow *parent)
  81         : VideoView (viewer)
  82         , _context (nullptr)
  83         , _vsync_enabled (false)
  84         , _playing (false)
  85         , _one_shot (false)
  86 {
  87         wxGLAttributes attributes;
  88         /* We don't need a depth buffer, and indeed there is apparently a bug with Windows/Intel HD 630
  89          * which puts green lines over the OpenGL display if you have a non-zero depth buffer size.
  90          * https://community.intel.com/t5/Graphics/Request-for-details-on-Intel-HD-630-green-lines-in-OpenGL-apps/m-p/1202179
  91          */
  92         attributes.PlatformDefaults().MinRGBA(8, 8, 8, 8).DoubleBuffer().Depth(0).EndList();
  93         _canvas = new wxGLCanvas (
  94                 parent, attributes, wxID_ANY, wxDefaultPosition, wxDefaultSize, wxFULL_REPAINT_ON_RESIZE
  95         );
  96         _canvas->Bind (wxEVT_PAINT, boost::bind(&GLVideoView::update, this));
  97         _canvas->Bind (wxEVT_SIZE, boost::bind(&GLVideoView::size_changed, this, _1));
  98
  99         _canvas->Bind (wxEVT_TIMER, boost::bind(&GLVideoView::check_for_butler_errors, this));
 100         _timer.reset (new wxTimer(_canvas));
 101         _timer->Start (2000);
 102 }
 103
 104
 105 void
 106 GLVideoView::size_changed (wxSizeEvent const& ev)
 107 {
 108         auto const scale = _canvas->GetDPIScaleFactor();
 109         int const width = std::round(ev.GetSize().GetWidth() * scale);
 110         int const height = std::round(ev.GetSize().GetHeight() * scale);
 111         _canvas_size = { width, height };
 112         LOG_GENERAL("GLVideoView canvas size changed to %1x%2", width, height);
 113         Sized ();
 114 }
 115
 116
 117 GLVideoView::~GLVideoView ()
 118 {
 119         boost::this_thread::disable_interruption dis;
 120
 121         try {
 122                 _thread.interrupt ();
 123                 _thread.join ();
 124         } catch (...) {}
 125 }
 126
 127 void
 128 GLVideoView::check_for_butler_errors ()
 129 {
 130         if (!_viewer->butler()) {
 131                 return;
 132         }
 133
 134         try {
 135                 _viewer->butler()->rethrow ();
 136         } catch (DecodeError& e) {
 137                 error_dialog (get(), e.what());
 138         } catch (dcp::ReadError& e) {
 139                 error_dialog (get(), wxString::Format(_("Could not read DCP: %s"), std_to_wx(e.what())));
 140         }
 141 }
 142
 143
 144 /** Called from the UI thread */
 145 void
 146 GLVideoView::update ()
 147 {
 148         if (!_canvas->IsShownOnScreen()) {
 149                 return;
 150         }
 151
 152         /* It appears important to do this from the GUI thread; if we do it from the GL thread
 153          * on Linux we get strange failures to create the context for any version of GL higher
 154          * than 3.2.
 155          */
 156         ensure_context ();
 157
 158 #ifdef DCPOMATIC_OSX
 159         /* macOS gives errors if we don't do this (and therefore [NSOpenGLContext setView:]) from the main thread */
 160         if (!_setup_shaders_done) {
 161                 setup_shaders ();
 162                 _setup_shaders_done = true;
 163         }
 164 #endif
 165
 166         if (!_thread.joinable()) {
 167                 _thread = boost::thread (boost::bind(&GLVideoView::thread, this));
 168         }
 169
 170         request_one_shot ();
 171
 172         rethrow ();
 173 }
 174
 175
 176 static constexpr char vertex_source[] =
 177 "#version 330 core\n"
 178 "\n"
 179 "layout (location = 0) in vec3 in_pos;\n"
 180 "layout (location = 1) in vec2 in_tex_coord;\n"
 181 "\n"
 182 "out vec2 TexCoord;\n"
 183 "\n"
 184 "void main()\n"
 185 "{\n"
 186 "       gl_Position = vec4(in_pos, 1.0);\n"
 187 "       TexCoord = in_tex_coord;\n"
 188 "}\n";
 189
 190
 191 /* Bicubic interpolation stolen from https://stackoverflow.com/questions/13501081/efficient-bicubic-filtering-code-in-glsl */
 192 static constexpr char fragment_source[] =
 193 "#version 330 core\n"
 194 "\n"
 195 "in vec2 TexCoord;\n"
 196 "\n"
 197 "uniform sampler2D texture_sampler;\n"
 198 /* type = 0: draw outline content rectangle
 199  * type = 1: draw crop guess rectangle
 200  * type = 2: draw XYZ image
 201  * type = 3: draw RGB image
 202  * See FragmentType enum below.
 203  */
 204 "uniform int type = 0;\n"
 205 "uniform vec4 outline_content_colour;\n"
 206 "uniform vec4 crop_guess_colour;\n"
 207 "uniform mat4 colour_conversion;\n"
 208 "\n"
 209 "out vec4 FragColor;\n"
 210 "\n"
 211 "vec4 cubic(float x)\n"
 212 "\n"
 213 "#define IN_GAMMA 2.2\n"
 214 "#define OUT_GAMMA 0.384615385\n"       //  1 /  2.6
 215 "#define DCI_COEFFICIENT 0.91655528\n"  // 48 / 53.37
 216 "\n"
 217 "{\n"
 218 "    float x2 = x * x;\n"
 219 "    float x3 = x2 * x;\n"
 220 "    vec4 w;\n"
 221 "    w.x =     -x3 + 3 * x2 - 3 * x + 1;\n"
 222 "    w.y =  3 * x3 - 6 * x2         + 4;\n"
 223 "    w.z = -3 * x3 + 3 * x2 + 3 * x + 1;\n"
 224 "    w.w =  x3;\n"
 225 "    return w / 6.f;\n"
 226 "}\n"
 227 "\n"
 228 "vec4 texture_bicubic(sampler2D sampler, vec2 tex_coords)\n"
 229 "{\n"
 230 "   vec2 tex_size = textureSize(sampler, 0);\n"
 231 "   vec2 inv_tex_size = 1.0 / tex_size;\n"
 232 "\n"
 233 "   tex_coords = tex_coords * tex_size - 0.5;\n"
 234 "\n"
 235 "   vec2 fxy = fract(tex_coords);\n"
 236 "   tex_coords -= fxy;\n"
 237 "\n"
 238 "   vec4 xcubic = cubic(fxy.x);\n"
 239 "   vec4 ycubic = cubic(fxy.y);\n"
 240 "\n"
 241 "   vec4 c = tex_coords.xxyy + vec2 (-0.5, +1.5).xyxy;\n"
 242 "\n"
 243 "   vec4 s = vec4(xcubic.xz + xcubic.yw, ycubic.xz + ycubic.yw);\n"
 244 "   vec4 offset = c + vec4 (xcubic.yw, ycubic.yw) / s;\n"
 245 "\n"
 246 "   offset *= inv_tex_size.xxyy;\n"
 247 "\n"
 248 "   vec4 sample0 = texture(sampler, offset.xz);\n"
 249 "   vec4 sample1 = texture(sampler, offset.yz);\n"
 250 "   vec4 sample2 = texture(sampler, offset.xw);\n"
 251 "   vec4 sample3 = texture(sampler, offset.yw);\n"
 252 "\n"
 253 "   float sx = s.x / (s.x + s.y);\n"
 254 "   float sy = s.z / (s.z + s.w);\n"
 255 "\n"
 256 "   return mix(\n"
 257 "          mix(sample3, sample2, sx), mix(sample1, sample0, sx)\n"
 258 "          , sy);\n"
 259 "}\n"
 260 "\n"
 261 "void main()\n"
 262 "{\n"
 263 "       switch (type) {\n"
 264 "               case 0:\n"
 265 "                       FragColor = outline_content_colour;\n"
 266 "                       break;\n"
 267 "               case 1:\n"
 268 "                       FragColor = crop_guess_colour;\n"
 269 "                       break;\n"
 270 "               case 2:\n"
 271 "                       FragColor = texture_bicubic(texture_sampler, TexCoord);\n"
 272 "                       FragColor.x = pow(FragColor.x, IN_GAMMA) / DCI_COEFFICIENT;\n"
 273 "                       FragColor.y = pow(FragColor.y, IN_GAMMA) / DCI_COEFFICIENT;\n"
 274 "                       FragColor.z = pow(FragColor.z, IN_GAMMA) / DCI_COEFFICIENT;\n"
 275 "                       FragColor = colour_conversion * FragColor;\n"
 276 "                       FragColor.x = pow(FragColor.x, OUT_GAMMA);\n"
 277 "                       FragColor.y = pow(FragColor.y, OUT_GAMMA);\n"
 278 "                       FragColor.z = pow(FragColor.z, OUT_GAMMA);\n"
 279 "                       break;\n"
 280 "               case 3:\n"
 281 "                       FragColor = texture_bicubic(texture_sampler, TexCoord);\n"
 282 "                       break;\n"
 283 "       }\n"
 284 "}\n";
 285
 286
 287 enum class FragmentType
 288 {
 289         OUTLINE_CONTENT = 0,
 290         CROP_GUESS = 1,
 291         XYZ_IMAGE = 2,
 292         RGB_IMAGE = 3,
 293 };
 294
 295
 296 void
 297 GLVideoView::ensure_context ()
 298 {
 299         if (!_context) {
 300                 wxGLContextAttrs attrs;
 301                 attrs.PlatformDefaults().CoreProfile().OGLVersion(4, 1).EndList();
 302                 _context = new wxGLContext (_canvas, nullptr, &attrs);
 303                 if (!_context->IsOK()) {
 304                         throw GLError ("Making GL context", -1);
 305                 }
 306         }
 307 }
 308
 309
 310 /* Offset and number of indices for the things in the indices array below */
 311 static constexpr int indices_video_texture_offset = 0;
 312 static constexpr int indices_video_texture_number = 6;
 313 static constexpr int indices_subtitle_texture_offset = indices_video_texture_offset + indices_video_texture_number;
 314 static constexpr int indices_subtitle_texture_number = 6;
 315 static constexpr int indices_outline_content_offset = indices_subtitle_texture_offset + indices_subtitle_texture_number;
 316 static constexpr int indices_outline_content_number = 8;
 317 static constexpr int indices_crop_guess_offset = indices_outline_content_offset + indices_outline_content_number;
 318 static constexpr int indices_crop_guess_number = 8;
 319
 320 static constexpr unsigned int indices[] = {
 321         0, 1, 3, // video texture triangle #1
 322         1, 2, 3, // video texture triangle #2
 323         4, 5, 7, // subtitle texture triangle #1
 324         5, 6, 7, // subtitle texture triangle #2
 325         8, 9,    // outline content line #1
 326         9, 10,   // outline content line #2
 327         10, 11,  // outline content line #3
 328         11, 8,   // outline content line #4
 329         12, 13,  // crop guess line #1
 330         13, 14,  // crop guess line #2
 331         14, 15,  // crop guess line #3
 332         15, 12,  // crop guess line #4
 333 };
 334
 335 /* Offsets of things in the GL_ARRAY_BUFFER */
 336 static constexpr int array_buffer_video_offset = 0;
 337 static constexpr int array_buffer_subtitle_offset = array_buffer_video_offset + 4 * 5 * sizeof(float);
 338 static constexpr int array_buffer_outline_content_offset = array_buffer_subtitle_offset + 4 * 5 * sizeof(float);
 339 static constexpr int array_buffer_crop_guess_offset = array_buffer_outline_content_offset + 4 * 5 * sizeof(float);
 340
 341
 342 void
 343 GLVideoView::setup_shaders ()
 344 {
 345         DCPOMATIC_ASSERT (_canvas);
 346         DCPOMATIC_ASSERT (_context);
 347         auto r = _canvas->SetCurrent (*_context);
 348         DCPOMATIC_ASSERT (r);
 349
 350 #ifdef DCPOMATIC_WINDOWS
 351         r = glewInit();
 352         if (r != GLEW_OK) {
 353                 throw GLError(reinterpret_cast<char const*>(glewGetErrorString(r)));
 354         }
 355 #endif
 356
 357         auto get_information = [this](GLenum name) {
 358                 auto s = glGetString (name);
 359                 if (s) {
 360                         _information[name] = std::string (reinterpret_cast<char const *>(s));
 361                 }
 362         };
 363
 364         get_information (GL_VENDOR);
 365         get_information (GL_RENDERER);
 366         get_information (GL_VERSION);
 367         get_information (GL_SHADING_LANGUAGE_VERSION);
 368
 369         glGenVertexArrays(1, &_vao);
 370         check_gl_error ("glGenVertexArrays");
 371         GLuint vbo;
 372         glGenBuffers(1, &vbo);
 373         check_gl_error ("glGenBuffers");
 374         GLuint ebo;
 375         glGenBuffers(1, &ebo);
 376         check_gl_error ("glGenBuffers");
 377
 378         glBindVertexArray(_vao);
 379         check_gl_error ("glBindVertexArray");
 380
 381         glBindBuffer(GL_ARRAY_BUFFER, vbo);
 382         check_gl_error ("glBindBuffer");
 383
 384         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo);
 385         check_gl_error ("glBindBuffer");
 386         glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
 387         check_gl_error ("glBufferData");
 388
 389         /* position attribute to vertex shader (location = 0) */
 390         glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float), nullptr);
 391         glEnableVertexAttribArray(0);
 392         /* texture coord attribute to vertex shader (location = 1) */
 393         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, 5 * sizeof(float), reinterpret_cast<void*>(3 * sizeof(float)));
 394         glEnableVertexAttribArray(1);
 395         check_gl_error ("glEnableVertexAttribArray");
 396
 397         auto compile = [](GLenum type, char const* source) -> GLuint {
 398                 auto shader = glCreateShader(type);
 399                 DCPOMATIC_ASSERT (shader);
 400                 GLchar const * src[] = { static_cast<GLchar const *>(source) };
 401                 glShaderSource(shader, 1, src, nullptr);
 402                 check_gl_error ("glShaderSource");
 403                 glCompileShader(shader);
 404                 check_gl_error ("glCompileShader");
 405                 GLint ok;
 406                 glGetShaderiv(shader, GL_COMPILE_STATUS, &ok);
 407                 if (!ok) {
 408                         GLint log_length;
 409                         glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &log_length);
 410                         string log;
 411                         if (log_length > 0) {
 412                                 std::vector<char> log_char(log_length);
 413                                 glGetShaderInfoLog(shader, log_length, nullptr, log_char.data());
 414                                 log = string(log_char.data());
 415                         }
 416                         glDeleteShader(shader);
 417                         throw GLError(String::compose("Could not compile shader (%1)", log).c_str(), -1);
 418                 }
 419                 return shader;
 420         };
 421
 422         auto vertex_shader = compile (GL_VERTEX_SHADER, vertex_source);
 423         auto fragment_shader = compile (GL_FRAGMENT_SHADER, fragment_source);
 424
 425         auto program = glCreateProgram();
 426         check_gl_error ("glCreateProgram");
 427         glAttachShader (program, vertex_shader);
 428         check_gl_error ("glAttachShader");
 429         glAttachShader (program, fragment_shader);
 430         check_gl_error ("glAttachShader");
 431         glLinkProgram (program);
 432         check_gl_error ("glLinkProgram");
 433         GLint ok;
 434         glGetProgramiv (program, GL_LINK_STATUS, &ok);
 435         if (!ok) {
 436                 GLint log_length;
 437                 glGetProgramiv(program, GL_INFO_LOG_LENGTH, &log_length);
 438                 string log;
 439                 if (log_length > 0) {
 440                         std::vector<char> log_char(log_length);
 441                         glGetProgramInfoLog(program, log_length, nullptr, log_char.data());
 442                         log = string(log_char.data());
 443                 }
 444                 glDeleteProgram (program);
 445                 throw GLError(String::compose("Could not link shader (%1)", log).c_str(), -1);
 446         }
 447         glDeleteShader (vertex_shader);
 448         glDeleteShader (fragment_shader);
 449
 450         glUseProgram (program);
 451
 452         _fragment_type = glGetUniformLocation (program, "type");
 453         check_gl_error ("glGetUniformLocation");
 454         set_outline_content_colour (program);
 455         set_crop_guess_colour (program);
 456
 457         auto conversion = dcp::ColourConversion::rec709_to_xyz();
 458         boost::numeric::ublas::matrix<double> matrix = conversion.xyz_to_rgb ();
 459         GLfloat gl_matrix[] = {
 460                 static_cast<float>(matrix(0, 0)), static_cast<float>(matrix(0, 1)), static_cast<float>(matrix(0, 2)), 0.0f,
 461                 static_cast<float>(matrix(1, 0)), static_cast<float>(matrix(1, 1)), static_cast<float>(matrix(1, 2)), 0.0f,
 462                 static_cast<float>(matrix(2, 0)), static_cast<float>(matrix(2, 1)), static_cast<float>(matrix(2, 2)), 0.0f,
 463                 0.0f, 0.0f, 0.0f, 1.0f
 464                 };
 465
 466         auto colour_conversion = glGetUniformLocation (program, "colour_conversion");
 467         check_gl_error ("glGetUniformLocation");
 468         glUniformMatrix4fv (colour_conversion, 1, GL_TRUE, gl_matrix);
 469
 470         glLineWidth (2.0f);
 471         check_gl_error ("glLineWidth");
 472         glEnable (GL_BLEND);
 473         check_gl_error ("glEnable");
 474         glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 475         check_gl_error ("glBlendFunc");
 476
 477         /* Reserve space for the GL_ARRAY_BUFFER */
 478         glBufferData(GL_ARRAY_BUFFER, 16 * 5 * sizeof(float), nullptr, GL_STATIC_DRAW);
 479         check_gl_error ("glBufferData");
 480 }
 481
 482
 483 void
 484 GLVideoView::set_outline_content_colour (GLuint program)
 485 {
 486         auto uniform = glGetUniformLocation (program, "outline_content_colour");
 487         check_gl_error ("glGetUniformLocation");
 488         auto colour = outline_content_colour ();
 489         glUniform4f (uniform, colour.Red() / 255.0f, colour.Green() / 255.0f, colour.Blue() / 255.0f, 1.0f);
 490         check_gl_error ("glUniform4f");
 491 }
 492
 493
 494 void
 495 GLVideoView::set_crop_guess_colour (GLuint program)
 496 {
 497         auto uniform = glGetUniformLocation (program, "crop_guess_colour");
 498         check_gl_error ("glGetUniformLocation");
 499         auto colour = crop_guess_colour ();
 500         glUniform4f (uniform, colour.Red() / 255.0f, colour.Green() / 255.0f, colour.Blue() / 255.0f, 1.0f);
 501         check_gl_error ("glUniform4f");
 502 }
 503
 504
 505 void
 506 GLVideoView::draw ()
 507 {
 508         auto pad = pad_colour();
 509         glClearColor(pad.Red() / 255.0, pad.Green() / 255.0, pad.Blue() / 255.0, 1.0);
 510         glClear (GL_COLOR_BUFFER_BIT);
 511         check_gl_error ("glClear");
 512
 513         auto const size = _canvas_size.load();
 514         int const width = size.GetWidth();
 515         int const height = size.GetHeight();
 516
 517         if (width < 64 || height < 0) {
 518                 return;
 519         }
 520
 521         glViewport (0, 0, width, height);
 522         check_gl_error ("glViewport");
 523
 524         glBindVertexArray(_vao);
 525         check_gl_error ("glBindVertexArray");
 526         glUniform1i(_fragment_type, static_cast<GLint>(_optimise_for_j2k ? FragmentType::XYZ_IMAGE : FragmentType::RGB_IMAGE));
 527         _video_texture->bind();
 528         glDrawElements (GL_TRIANGLES, indices_video_texture_number, GL_UNSIGNED_INT, reinterpret_cast<void*>(indices_video_texture_offset * sizeof(int)));
 529         if (_have_subtitle_to_render) {
 530                 glUniform1i(_fragment_type, static_cast<GLint>(FragmentType::RGB_IMAGE));
 531                 _subtitle_texture->bind();
 532                 glDrawElements (GL_TRIANGLES, indices_subtitle_texture_number, GL_UNSIGNED_INT, reinterpret_cast<void*>(indices_subtitle_texture_offset * sizeof(int)));
 533         }
 534         if (_viewer->outline_content()) {
 535                 glUniform1i(_fragment_type, static_cast<GLint>(FragmentType::OUTLINE_CONTENT));
 536                 glDrawElements (GL_LINES, indices_outline_content_number, GL_UNSIGNED_INT, reinterpret_cast<void*>(indices_outline_content_offset * sizeof(int)));
 537                 check_gl_error ("glDrawElements");
 538         }
 539         if (auto guess = _viewer->crop_guess()) {
 540                 glUniform1i(_fragment_type, 1);
 541                 glDrawElements (GL_LINES, indices_crop_guess_number, GL_UNSIGNED_INT, reinterpret_cast<void*>(indices_crop_guess_offset * sizeof(int)));
 542                 check_gl_error ("glDrawElements");
 543         }
 544
 545         glFlush();
 546         check_gl_error ("glFlush");
 547
 548         _canvas->SwapBuffers();
 549 }
 550
 551
 552 void
 553 GLVideoView::set_image (shared_ptr<const PlayerVideo> pv)
 554 {
 555         shared_ptr<const Image> video = _optimise_for_j2k ? pv->raw_image() : pv->image(bind(&PlayerVideo::force, AV_PIX_FMT_RGB24), VideoRange::FULL, true);
 556
 557         /* Only the player's black frames should be aligned at this stage, so this should
 558          * almost always have no work to do.
 559          */
 560         video = Image::ensure_alignment (video, Image::Alignment::COMPACT);
 561
 562         /** If _optimise_for_j2k is true we render a XYZ image, doing the colourspace
 563          *  conversion, scaling and video range conversion in the GL shader.
 564          *  Othewise we render a RGB image without any shader-side processing.
 565          */
 566
 567         /* XXX: video range conversion */
 568
 569         _video_texture->set (video);
 570
 571         auto const text = pv->text();
 572         _have_subtitle_to_render = static_cast<bool>(text) && _optimise_for_j2k;
 573         if (_have_subtitle_to_render) {
 574                 /* opt: only do this if it's a new subtitle? */
 575                 DCPOMATIC_ASSERT (text->image->alignment() == Image::Alignment::COMPACT);
 576                 _subtitle_texture->set (text->image);
 577         }
 578
 579
 580         auto const canvas_size = _canvas_size.load();
 581         int const canvas_width = canvas_size.GetWidth();
 582         int const canvas_height = canvas_size.GetHeight();
 583         auto const inter_position = player_video().first->inter_position();
 584         auto const inter_size = player_video().first->inter_size();
 585         auto const out_size = player_video().first->out_size();
 586         auto const crop_guess = _viewer->crop_guess();
 587
 588         auto x_offset = std::max(0, (canvas_width - out_size.width) / 2);
 589         auto y_offset = std::max(0, (canvas_height - out_size.height) / 2);
 590
 591         _last_canvas_size.set_next (canvas_size);
 592         _last_video_size.set_next (video->size());
 593         _last_inter_position.set_next (inter_position);
 594         _last_inter_size.set_next (inter_size);
 595         _last_out_size.set_next (out_size);
 596         _last_crop_guess.set_next (crop_guess);
 597
 598         class Rectangle
 599         {
 600         public:
 601                 Rectangle (wxSize canvas_size, float x, float y, dcp::Size size)
 602                         : _canvas_size (canvas_size)
 603                 {
 604                         auto const x1 = x_pixels_to_gl(x);
 605                         auto const y1 = y_pixels_to_gl(y);
 606                         auto const x2 = x_pixels_to_gl(x + size.width);
 607                         auto const y2 = y_pixels_to_gl(y + size.height);
 608
 609                         /* The texture coordinates here have to account for the fact that when we put images into the texture OpenGL
 610                          * expected us to start at the lower left but we actually started at the top left.  So although the
 611                          * top of the texture is at 1.0 we pretend it's the other way round.
 612                          */
 613
 614                         // bottom right
 615                         _vertices[0] = x2;
 616                         _vertices[1] = y2;
 617                         _vertices[2] = 0.0f;
 618                         _vertices[3] = 1.0f;
 619                         _vertices[4] = 1.0f;
 620
 621                         // top right
 622                         _vertices[5] = x2;
 623                         _vertices[6] = y1;
 624                         _vertices[7] = 0.0f;
 625                         _vertices[8] = 1.0f;
 626                         _vertices[9] = 0.0f;
 627
 628                         // top left
 629                         _vertices[10] = x1;
 630                         _vertices[11] = y1;
 631                         _vertices[12] = 0.0f;
 632                         _vertices[13] = 0.0f;
 633                         _vertices[14] = 0.0f;
 634
 635                         // bottom left
 636                         _vertices[15] = x1;
 637                         _vertices[16] = y2;
 638                         _vertices[17] = 0.0f;
 639                         _vertices[18] = 0.0f;
 640                         _vertices[19] = 1.0f;
 641                 }
 642
 643                 float const * vertices () const {
 644                         return _vertices;
 645                 }
 646
 647                 int const size () const {
 648                         return sizeof(_vertices);
 649                 }
 650
 651         private:
 652                 /* @param x x position in pixels where 0 is left and canvas_width is right on screen */
 653                 float x_pixels_to_gl(int x) const {
 654                         return (x * 2.0f / _canvas_size.GetWidth()) - 1.0f;
 655                 }
 656
 657                 /* @param y y position in pixels where 0 is top and canvas_height is bottom on screen */
 658                 float y_pixels_to_gl(int y) const {
 659                         return 1.0f - (y * 2.0f / _canvas_size.GetHeight());
 660                 }
 661
 662                 wxSize _canvas_size;
 663                 float _vertices[20];
 664         };
 665
 666         auto const sizing_changed = _last_canvas_size.changed() || _last_inter_position.changed() || _last_inter_size.changed() || _last_out_size.changed();
 667
 668         if (sizing_changed) {
 669                 const auto video = _optimise_for_j2k ?
 670                         Rectangle(canvas_size, inter_position.x + x_offset, inter_position.y + y_offset, inter_size)
 671                         : Rectangle(canvas_size, x_offset, y_offset, out_size);
 672
 673                 glBufferSubData (GL_ARRAY_BUFFER, array_buffer_video_offset, video.size(), video.vertices());
 674                 check_gl_error ("glBufferSubData (video)");
 675
 676                 const auto outline_content = Rectangle(canvas_size, inter_position.x + x_offset, inter_position.y + y_offset, inter_size);
 677                 glBufferSubData (GL_ARRAY_BUFFER, array_buffer_outline_content_offset, outline_content.size(), outline_content.vertices());
 678                 check_gl_error ("glBufferSubData (outline_content)");
 679         }
 680
 681         if ((sizing_changed || _last_crop_guess.changed()) && crop_guess) {
 682                 auto const crop_guess_rectangle = Rectangle(
 683                         canvas_size,
 684                         inter_position.x + x_offset + inter_size.width * crop_guess->x,
 685                         inter_position.y + y_offset + inter_size.height * crop_guess->y,
 686                         dcp::Size(inter_size.width * crop_guess->width, inter_size.height * crop_guess->height)
 687                         );
 688                 glBufferSubData (GL_ARRAY_BUFFER, array_buffer_crop_guess_offset, crop_guess_rectangle.size(), crop_guess_rectangle.vertices());
 689                 check_gl_error ("glBufferSubData (crop_guess_rectangle)");
 690         }
 691
 692         if (_have_subtitle_to_render) {
 693                 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());
 694                 glBufferSubData (GL_ARRAY_BUFFER, array_buffer_subtitle_offset, subtitle.size(), subtitle.vertices());
 695                 check_gl_error ("glBufferSubData (subtitle)");
 696         }
 697
 698         /* opt: where should these go? */
 699
 700         glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 701         glTexParameteri (GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 702         check_gl_error ("glTexParameteri");
 703
 704         glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 705         glTexParameterf (GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 706         check_gl_error ("glTexParameterf");
 707 }
 708
 709
 710 void
 711 GLVideoView::start ()
 712 {
 713         VideoView::start ();
 714
 715         boost::mutex::scoped_lock lm (_playing_mutex);
 716         _playing = true;
 717         _thread_work_condition.notify_all ();
 718 }
 719
 720 void
 721 GLVideoView::stop ()
 722 {
 723         boost::mutex::scoped_lock lm (_playing_mutex);
 724         _playing = false;
 725 }
 726
 727
 728 void
 729 GLVideoView::thread_playing ()
 730 {
 731         if (length() != dcpomatic::DCPTime()) {
 732                 auto const next = position() + one_video_frame();
 733
 734                 if (next >= length()) {
 735                         _viewer->finished ();
 736                         return;
 737                 }
 738
 739                 get_next_frame (false);
 740                 set_image_and_draw ();
 741         }
 742
 743         while (true) {
 744                 optional<int> n = time_until_next_frame();
 745                 if (!n || *n > 5) {
 746                         break;
 747                 }
 748                 get_next_frame (true);
 749                 add_dropped ();
 750         }
 751 }
 752
 753
 754 void
 755 GLVideoView::set_image_and_draw ()
 756 {
 757         auto pv = player_video().first;
 758         if (pv) {
 759                 set_image (pv);
 760         }
 761
 762         draw ();
 763
 764         if (pv) {
 765                 _viewer->image_changed (pv);
 766         }
 767 }
 768
 769
 770 void
 771 GLVideoView::thread ()
 772 try
 773 {
 774         start_of_thread ("GLVideoView");
 775
 776 #if defined(DCPOMATIC_OSX)
 777         /* Without this we see errors like
 778          * ../src/osx/cocoa/glcanvas.mm(194): assert ""context"" failed in SwapBuffers(): should have current context [in thread 700006970000]
 779          */
 780         WXGLSetCurrentContext (_context->GetWXGLContext());
 781 #else
 782         if (!_setup_shaders_done) {
 783                 setup_shaders ();
 784                 _setup_shaders_done = true;
 785         }
 786 #endif
 787
 788 #if defined(DCPOMATIC_LINUX) && defined(DCPOMATIC_HAVE_GLX_SWAP_INTERVAL_EXT)
 789         if (_canvas->IsExtensionSupported("GLX_EXT_swap_control")) {
 790                 /* Enable vsync */
 791                 Display* dpy = wxGetX11Display();
 792                 glXSwapIntervalEXT (dpy, DefaultScreen(dpy), 1);
 793                 _vsync_enabled = true;
 794         }
 795 #endif
 796
 797 #ifdef DCPOMATIC_WINDOWS
 798         if (_canvas->IsExtensionSupported("WGL_EXT_swap_control")) {
 799                 /* Enable vsync */
 800                 PFNWGLSWAPINTERVALEXTPROC swap = (PFNWGLSWAPINTERVALEXTPROC) wglGetProcAddress("wglSwapIntervalEXT");
 801                 if (swap) {
 802                         swap (1);
 803                         _vsync_enabled = true;
 804                 }
 805         }
 806
 807 #endif
 808
 809 #ifdef DCPOMATIC_OSX
 810         /* Enable vsync */
 811         GLint swapInterval = 1;
 812         CGLSetParameter (CGLGetCurrentContext(), kCGLCPSwapInterval, &swapInterval);
 813         _vsync_enabled = true;
 814 #endif
 815
 816         _video_texture.reset(new Texture(_optimise_for_j2k ? 2 : 1));
 817         _subtitle_texture.reset(new Texture(1));
 818
 819         while (true) {
 820                 boost::mutex::scoped_lock lm (_playing_mutex);
 821                 while (!_playing && !_one_shot) {
 822                         _thread_work_condition.wait (lm);
 823                 }
 824                 lm.unlock ();
 825
 826                 if (_playing) {
 827                         thread_playing ();
 828                 } else if (_one_shot) {
 829                         _one_shot = false;
 830                         set_image_and_draw ();
 831                 }
 832
 833                 boost::this_thread::interruption_point ();
 834                 dcpomatic_sleep_milliseconds (time_until_next_frame().get_value_or(0));
 835         }
 836
 837         /* XXX: leaks _context, but that seems preferable to deleting it here
 838          * without also deleting the wxGLCanvas.
 839          */
 840 }
 841 catch (...)
 842 {
 843         store_current ();
 844 }
 845
 846
 847 VideoView::NextFrameResult
 848 GLVideoView::display_next_frame (bool non_blocking)
 849 {
 850         NextFrameResult const r = get_next_frame (non_blocking);
 851         request_one_shot ();
 852         return r;
 853 }
 854
 855
 856 void
 857 GLVideoView::request_one_shot ()
 858 {
 859         boost::mutex::scoped_lock lm (_playing_mutex);
 860         _one_shot = true;
 861         _thread_work_condition.notify_all ();
 862 }
 863
 864
 865 Texture::Texture (GLint unpack_alignment)
 866         : _unpack_alignment (unpack_alignment)
 867 {
 868         glGenTextures (1, &_name);
 869         check_gl_error ("glGenTextures");
 870 }
 871
 872
 873 Texture::~Texture ()
 874 {
 875         glDeleteTextures (1, &_name);
 876 }
 877
 878
 879 void
 880 Texture::bind ()
 881 {
 882         glBindTexture(GL_TEXTURE_2D, _name);
 883         check_gl_error ("glBindTexture");
 884 }
 885
 886
 887 void
 888 Texture::set (shared_ptr<const Image> image)
 889 {
 890         auto const create = !_size || image->size() != _size;
 891         _size = image->size();
 892
 893         glPixelStorei (GL_UNPACK_ALIGNMENT, _unpack_alignment);
 894         check_gl_error ("glPixelStorei");
 895
 896         DCPOMATIC_ASSERT (image->alignment() == Image::Alignment::COMPACT);
 897
 898         GLint internal_format;
 899         GLenum format;
 900         GLenum type;
 901
 902         switch (image->pixel_format()) {
 903         case AV_PIX_FMT_BGRA:
 904                 internal_format = GL_RGBA8;
 905                 format = GL_BGRA;
 906                 type = GL_UNSIGNED_BYTE;
 907                 break;
 908         case AV_PIX_FMT_RGBA:
 909                 internal_format = GL_RGBA8;
 910                 format = GL_RGBA;
 911                 type = GL_UNSIGNED_BYTE;
 912                 break;
 913         case AV_PIX_FMT_RGB24:
 914                 internal_format = GL_RGBA8;
 915                 format = GL_RGB;
 916                 type = GL_UNSIGNED_BYTE;
 917                 break;
 918         case AV_PIX_FMT_XYZ12:
 919                 internal_format = GL_RGBA12;
 920                 format = GL_RGB;
 921                 type = GL_UNSIGNED_SHORT;
 922                 break;
 923         default:
 924                 throw PixelFormatError ("Texture::set", image->pixel_format());
 925         }
 926
 927         bind ();
 928
 929         if (create) {
 930                 glTexImage2D (GL_TEXTURE_2D, 0, internal_format, _size->width, _size->height, 0, format, type, image->data()[0]);
 931                 check_gl_error ("glTexImage2D");
 932         } else {
 933                 glTexSubImage2D (GL_TEXTURE_2D, 0, 0, 0, _size->width, _size->height, format, type, image->data()[0]);
 934                 check_gl_error ("glTexSubImage2D");
 935         }
 936 }
 937
 938 #endif