git.sesse.net Git - nageru/blob - nageru/scene.cpp

   1 #include <algorithm>
   2 #include <array>
   3 #include <assert.h>
   4 #include <bitset>
   5 #include <bmusb/bmusb.h>
   6 #include <math.h>
   7 #include <stddef.h>
   8 #include <stdio.h>
   9 #include <functional>
  10 #include <map>
  11 #include <movit/effect.h>
  12 #include <mutex>
  13 #include <string>
  14 #include <utility>
  15 #include <vector>
  16 extern "C" {
  17 #include <lauxlib.h>
  18 }
  19 #include <lua.hpp>
  20
  21 #ifdef HAVE_CEF
  22 #include "cef_capture.h"
  23 #endif
  24 #include "ffmpeg_capture.h"
  25 #include "flags.h"
  26 #include "image_input.h"
  27 #include "input_state.h"
  28 #include "lua_utils.h"
  29 #include "scene.h"
  30 #include "theme.h"
  31
  32 using namespace movit;
  33 using namespace std;
  34
  35 static bool display(Block *block, lua_State *L, int idx);
  36
  37 EffectType current_type(const Block *block)
  38 {
  39         return block->alternatives[block->currently_chosen_alternative]->effect_type;
  40 }
  41
  42 int find_index_of(const Block *block, EffectType val)
  43 {
  44         for (size_t idx = 0; idx < block->alternatives.size(); ++idx) {
  45                 if (block->alternatives[idx]->effect_type == val) {
  46                         return idx;
  47                 }
  48         }
  49         return -1;
  50 }
  51
  52 string get_declaration_point(lua_State *L)
  53 {
  54         lua_Debug ar;
  55         lua_getstack(L, 1, &ar);
  56         lua_getinfo(L, "nSl", &ar);
  57         char buf[256];
  58         snprintf(buf, sizeof(buf), "%s:%d", ar.source, ar.currentline);
  59         return buf;
  60 }
  61
  62 Scene::Scene(Theme *theme, float aspect_nom, float aspect_denom)
  63         : theme(theme), aspect_nom(aspect_nom), aspect_denom(aspect_denom), resource_pool(theme->get_resource_pool()) {}
  64
  65 size_t Scene::compute_chain_number(bool is_main_chain) const
  66 {
  67         assert(chains.size() > 0);
  68         assert(chains.size() % 2 == 0);
  69         bitset<256> disabled = find_disabled_blocks(size_t(-1));
  70
  71         size_t chain_number = compute_chain_number_for_block(blocks.size() - 1, disabled);
  72         assert(chain_number < chains.size() / 2);
  73         if (is_main_chain) {
  74                 chain_number += chains.size() / 2;
  75         }
  76         return chain_number;
  77 }
  78
  79 size_t Scene::compute_chain_number_for_block(size_t block_idx, const bitset<256> &disabled) const
  80 {
  81         Block *block = blocks[block_idx];
  82         size_t chain_number;
  83
  84         size_t currently_chosen_alternative;
  85         if (disabled.test(block_idx)) {
  86                 // It doesn't matter, so pick the canonical choice
  87                 // (this is the only one that is actually instantiated).
  88                 currently_chosen_alternative = block->canonical_alternative;
  89         } else {
  90                 currently_chosen_alternative = block->currently_chosen_alternative;
  91         }
  92         assert(currently_chosen_alternative < block->alternatives.size());
  93
  94         if (block_idx == 0) {
  95                 assert(block->cardinality_base == 1);
  96                 chain_number = currently_chosen_alternative;
  97         } else {
  98                 chain_number = compute_chain_number_for_block(block_idx - 1, disabled) + block->cardinality_base * currently_chosen_alternative;
  99         }
 100         return chain_number;
 101 }
 102
 103 bitset<256> Scene::find_disabled_blocks(size_t chain_idx) const
 104 {
 105         assert(blocks.size() < 256);
 106
 107         // The find_disabled_blocks() recursion logic needs only one pass by itself,
 108         // but the disabler logic is not so smart, so we just run multiple times
 109         // until it converges.
 110         bitset<256> prev, ret;
 111         do {
 112                 find_disabled_blocks(chain_idx, blocks.size() - 1, /*currently_disabled=*/false, &ret);
 113                 prev = ret;
 114
 115                 // Propagate DISABLE_IF_OTHER_DISABLED constraints (we can always do this).
 116                 for (Block *block : blocks) {
 117                         if (ret.test(block->idx)) continue;  // Already disabled.
 118
 119                         EffectType chosen_type = block->alternatives[block->chosen_alternative(chain_idx)]->effect_type;
 120                         if (chosen_type == IDENTITY_EFFECT) {
 121                                 ret.set(block->idx);
 122                                 continue;
 123                         }
 124
 125                         for (const Block::Disabler &disabler : block->disablers) {
 126                                 Block *other = blocks[disabler.block_idx];
 127                                 EffectType chosen_type = other->alternatives[other->chosen_alternative(chain_idx)]->effect_type;
 128                                 bool other_disabled = ret.test(disabler.block_idx) || chosen_type == IDENTITY_EFFECT;
 129                                 if (other_disabled && disabler.condition == Block::Disabler::DISABLE_IF_OTHER_DISABLED) {
 130                                         ret.set(block->idx);
 131                                         break;
 132                                 }
 133                         }
 134                 }
 135
 136                 // We cannot propagate DISABLE_IF_OTHER_ENABLED in all cases;
 137                 // the problem is that if A is disabled if B is enabled,
 138                 // then we cannot disable A unless we actually know for sure
 139                 // that B _is_ enabled. (E.g., imagine that B is disabled
 140                 // if C is enabled -- we couldn't disable A before we knew if
 141                 // C was enabled or not!)
 142                 //
 143                 // We could probably fix a fair amount of these, but the
 144                 // primary use case for DISABLE_IF_OTHER_ENABLED is really
 145                 // mutual exclusion; A must be disabled if B is enabled
 146                 // _and_ vice versa. These loops cannot be automatically
 147                 // resolved; it would depend on what A and B is. Thus,
 148                 // we simply declare this kind of constraint to be a promise
 149                 // from the user, not something that we'll solve for them.
 150         } while (prev != ret);
 151         return ret;
 152 }
 153
 154 void Scene::find_disabled_blocks(size_t chain_idx, size_t block_idx, bool currently_disabled, bitset<256> *disabled) const
 155 {
 156         if (currently_disabled) {
 157                 disabled->set(block_idx);
 158         }
 159         Block *block = blocks[block_idx];
 160         EffectType chosen_type = block->alternatives[block->chosen_alternative(chain_idx)]->effect_type;
 161         for (size_t input_idx = 0; input_idx < block->inputs.size(); ++input_idx) {
 162                 if (chosen_type == IDENTITY_EFFECT && input_idx > 0) {
 163                         // Multi-input effect that has been replaced by
 164                         // IdentityEffect, so every effect but the first are
 165                         // disabled and will not participate in the chain.
 166                         find_disabled_blocks(chain_idx, block->inputs[input_idx], /*currently_disabled=*/true, disabled);
 167                 } else {
 168                         // Just keep on recursing down.
 169                         find_disabled_blocks(chain_idx, block->inputs[input_idx], currently_disabled, disabled);
 170                 }
 171         }
 172 }
 173
 174 bool Scene::is_noncanonical_chain(size_t chain_idx) const
 175 {
 176         bitset<256> disabled = find_disabled_blocks(chain_idx);
 177         assert(blocks.size() < 256);
 178         for (size_t block_idx = 0; block_idx < blocks.size(); ++block_idx) {
 179                 Block *block = blocks[block_idx];
 180                 if (disabled.test(block_idx) && block->chosen_alternative(chain_idx) != block->canonical_alternative) {
 181                         return true;
 182                 }
 183
 184                 // Test if we're supposed to be disabled by some other block being enabled;
 185                 // the disabled bit mask does not fully capture this.
 186                 if (!disabled.test(block_idx)) {
 187                         for (const Block::Disabler &disabler : block->disablers) {
 188                                 if (disabler.condition == Block::Disabler::DISABLE_IF_OTHER_ENABLED &&
 189                                     !disabled.test(disabler.block_idx)) {
 190                                         return true;
 191                                 }
 192                         }
 193
 194                         // Auto white balance is always disabled for image inputs.
 195                         if (block->white_balance_controller_block != nullptr) {
 196                                 const Block *input = block->white_balance_controller_block;
 197                                 if (input->alternatives[input->chosen_alternative(chain_idx)]->effect_type == IMAGE_INPUT) {
 198                                         return true;
 199                                 }
 200                         }
 201                 }
 202         }
 203         return false;
 204 }
 205
 206 int Scene::add_input(lua_State* L)
 207 {
 208         assert(lua_gettop(L) == 1 || lua_gettop(L) == 2);
 209         Scene *scene = (Scene *)luaL_checkudata(L, 1, "Scene");
 210
 211         Block *block = new Block;
 212         block->declaration_point = get_declaration_point(L);
 213         block->idx = scene->blocks.size();
 214         if (lua_gettop(L) == 1) {
 215                 // No parameter given, so a flexible input.
 216                 block->alternatives.emplace_back(new EffectBlueprint(LIVE_INPUT_YCBCR));
 217                 block->alternatives.emplace_back(new EffectBlueprint(LIVE_INPUT_YCBCR_WITH_DEINTERLACE));
 218                 block->alternatives.emplace_back(new EffectBlueprint(LIVE_INPUT_YCBCR_PLANAR));
 219                 block->alternatives.emplace_back(new EffectBlueprint(LIVE_INPUT_BGRA));
 220                 block->alternatives.emplace_back(new EffectBlueprint(IMAGE_INPUT));
 221         } else {
 222                 // Input of a given type. We'll specialize it here, plus connect the input as given.
 223                 if (lua_isnumber(L, 2)) {
 224                         block->alternatives.emplace_back(new EffectBlueprint(LIVE_INPUT_YCBCR));
 225                         block->alternatives.emplace_back(new EffectBlueprint(LIVE_INPUT_YCBCR_WITH_DEINTERLACE));
 226 #ifdef HAVE_SRT
 227                         if (global_flags.srt_port >= 0) {
 228                                 block->alternatives.emplace_back(new EffectBlueprint(LIVE_INPUT_YCBCR_PLANAR));
 229                         }
 230 #endif
 231 #ifdef HAVE_CEF
 232                 } else if (luaL_testudata(L, 2, "HTMLInput")) {
 233                         block->alternatives.emplace_back(new EffectBlueprint(LIVE_INPUT_BGRA));
 234 #endif
 235                 } else if (luaL_testudata(L, 2, "VideoInput")) {
 236                         FFmpegCapture *capture = *(FFmpegCapture **)luaL_checkudata(L, 2, "VideoInput");
 237                         if (capture->get_current_pixel_format() == bmusb::PixelFormat_8BitYCbCrPlanar) {
 238                                 block->alternatives.emplace_back(new EffectBlueprint(LIVE_INPUT_YCBCR_PLANAR));
 239                         } else {
 240                                 assert(capture->get_current_pixel_format() == bmusb::PixelFormat_8BitBGRA);
 241                                 block->alternatives.emplace_back(new EffectBlueprint(LIVE_INPUT_BGRA));
 242                         }
 243                 } else if (luaL_testudata(L, 2, "ImageInput")) {
 244                         block->alternatives.emplace_back(new EffectBlueprint(IMAGE_INPUT));
 245                 } else {
 246                         luaL_error(L, "add_input() called with something that's not a signal (a signal number, a HTML input, or a VideoInput)");
 247                 }
 248                 bool ok = display(block, L, 2);
 249                 assert(ok);
 250         }
 251         block->is_input = true;
 252         scene->blocks.push_back(block);
 253
 254         return wrap_lua_existing_object_nonowned<Block>(L, "Block", block);
 255 }
 256
 257 Block *Scene::find_block_from_arg(lua_State *L, Scene *scene, int idx)
 258 {
 259         if (luaL_testudata(L, idx, "Block")) {
 260                 return *(Block **)luaL_checkudata(L, idx, "Block");
 261         } else {
 262                 EffectBlueprint *blueprint = *(EffectBlueprint **)luaL_checkudata(L, idx, "EffectBlueprint");
 263
 264                 // Search through all the blocks to figure out which one contains this effect.
 265                 for (Block *block : scene->blocks) {
 266                         if (find(block->alternatives.begin(), block->alternatives.end(), blueprint) != block->alternatives.end()) {
 267                                 return block;
 268                         }
 269                 }
 270                 luaL_error(L, "Input effect in parameter #%d has not been added to this scene", idx - 1);
 271                 return nullptr;  // Dead code.
 272         }
 273 }
 274
 275 void Scene::find_inputs_for_block(lua_State *L, Scene *scene, Block *block, int first_input_idx)
 276 {
 277         if (lua_gettop(L) == first_input_idx - 1) {
 278                 // Implicitly the last added effect.
 279                 assert(!scene->blocks.empty());
 280                 block->inputs.push_back(scene->blocks.size() - 1);
 281                 return;
 282         }
 283
 284         for (int idx = first_input_idx; idx <= lua_gettop(L); ++idx) {
 285                 block->inputs.push_back(find_block_from_arg(L, scene, idx)->idx);
 286         }
 287 }
 288
 289 int Scene::add_effect(lua_State* L)
 290 {
 291         assert(lua_gettop(L) >= 2);
 292         Scene *scene = (Scene *)luaL_checkudata(L, 1, "Scene");
 293
 294         Block *block = new Block;
 295         block->declaration_point = get_declaration_point(L);
 296         block->idx = scene->blocks.size();
 297
 298         if (lua_istable(L, 2)) {
 299                 size_t len = lua_objlen(L, 2);
 300                 for (size_t i = 0; i < len; ++i) {
 301                         lua_rawgeti(L, 2, i + 1);
 302                         EffectBlueprint *blueprint = *(EffectBlueprint **)luaL_checkudata(L, -1, "EffectBlueprint");
 303                         block->alternatives.push_back(blueprint);
 304                         lua_settop(L, -2);
 305                 }
 306         } else {
 307                 EffectBlueprint *blueprint = *(EffectBlueprint **)luaL_checkudata(L, 2, "EffectBlueprint");
 308                 block->alternatives.push_back(blueprint);
 309         }
 310
 311         int identity_index = find_index_of(block, IDENTITY_EFFECT);
 312         if (identity_index == -1) {
 313                 block->canonical_alternative = 0;
 314         } else {
 315                 // Pick the IdentityEffect as the canonical alternative, in case it
 316                 // helps us disable more stuff.
 317                 block->canonical_alternative = identity_index;
 318         }
 319
 320         find_inputs_for_block(L, scene, block);
 321         scene->blocks.push_back(block);
 322
 323         return wrap_lua_existing_object_nonowned<Block>(L, "Block", block);
 324 }
 325
 326 int Scene::add_optional_effect(lua_State* L)
 327 {
 328         assert(lua_gettop(L) >= 2);
 329         Scene *scene = (Scene *)luaL_checkudata(L, 1, "Scene");
 330
 331         Block *block = new Block;
 332         block->declaration_point = get_declaration_point(L);
 333         block->idx = scene->blocks.size();
 334
 335         EffectBlueprint *blueprint = *(EffectBlueprint **)luaL_checkudata(L, 2, "EffectBlueprint");
 336         block->alternatives.push_back(blueprint);
 337
 338         // An IdentityEffect will be the alternative for when the effect is disabled.
 339         block->alternatives.push_back(new EffectBlueprint(IDENTITY_EFFECT));
 340
 341         block->canonical_alternative = 1;
 342
 343         find_inputs_for_block(L, scene, block);
 344         scene->blocks.push_back(block);
 345
 346         return wrap_lua_existing_object_nonowned<Block>(L, "Block", block);
 347 }
 348
 349 const Block *Scene::find_root_input_block(lua_State *L, const Block *block)
 350 {
 351         if (block->is_input) {
 352                 assert(block->inputs.size() == 0);
 353                 return block;
 354         }
 355
 356         const Block *ret = nullptr;
 357         for (size_t input_idx : block->inputs) {
 358                 const Block *parent = find_root_input_block(L, blocks[input_idx]);
 359                 if (parent != nullptr) {
 360                         if (ret != nullptr) {
 361                                 luaL_error(L, "add_white_balance() was connected to more than one input");
 362                         }
 363                         ret = parent;
 364                 }
 365         }
 366         return ret;
 367 }
 368
 369 int Scene::add_white_balance(lua_State* L)
 370 {
 371         assert(lua_gettop(L) >= 1);
 372         Scene *scene = (Scene *)luaL_checkudata(L, 1, "Scene");
 373
 374         Block *block = new Block;
 375         block->declaration_point = get_declaration_point(L);
 376         block->idx = scene->blocks.size();
 377
 378         block->alternatives.push_back(new EffectBlueprint(WHITE_BALANCE_EFFECT));
 379         block->alternatives.push_back(new EffectBlueprint(IDENTITY_EFFECT));
 380
 381         block->canonical_alternative = 1;
 382
 383         if (lua_gettop(L) == 1) {
 384                 // The last added effect is implicitly both the input and gives the white balance controller.
 385                 assert(!scene->blocks.empty());
 386                 block->inputs.push_back(scene->blocks.size() - 1);
 387                 block->white_balance_controller_block = scene->find_root_input_block(L, block);
 388         } else if (lua_gettop(L) == 2) {
 389                 // The given effect is both the input and the white balance controller.
 390                 block->inputs.push_back(find_block_from_arg(L, scene, 2)->idx);
 391                 block->white_balance_controller_block = scene->find_root_input_block(L, block);
 392         } else if (lua_gettop(L) == 3) {
 393                 // We have explicit input and white balance controller.
 394                 block->inputs.push_back(find_block_from_arg(L, scene, 2)->idx);
 395                 block->white_balance_controller_block = find_block_from_arg(L, scene, 3);
 396         } else {
 397                 luaL_error(L, "add_white_balance([input], [white_balance_controller]) takes zero, one or two arguments");
 398         }
 399         if (block->white_balance_controller_block == nullptr || !block->white_balance_controller_block->is_input) {
 400                 luaL_error(L, "add_white_balance() does not get its white balance from an input");
 401         }
 402
 403         scene->blocks.push_back(block);
 404
 405         return wrap_lua_existing_object_nonowned<Block>(L, "Block", block);
 406 }
 407
 408 Effect *Scene::instantiate_effects(const Block *block, size_t chain_idx, Scene::Instantiation *instantiation)
 409 {
 410         // Find the chosen alternative for this block in this instance.
 411         EffectType chosen_type = block->alternatives[block->chosen_alternative(chain_idx)]->effect_type;
 412
 413         vector<Effect *> inputs;
 414         for (size_t input_idx : block->inputs) {
 415                 inputs.push_back(instantiate_effects(blocks[input_idx], chain_idx, instantiation));
 416
 417                 // As a special case, we allow IdentityEffect to take only one input
 418                 // even if the other alternative (or alternatives) is multi-input.
 419                 // Thus, even if there are more than one inputs, instantiate only
 420                 // the first one.
 421                 if (chosen_type == IDENTITY_EFFECT) {
 422                         break;
 423                 }
 424         }
 425
 426         Effect *effect;
 427         switch (chosen_type) {
 428         case LIVE_INPUT_YCBCR:
 429         case LIVE_INPUT_YCBCR_WITH_DEINTERLACE:
 430         case LIVE_INPUT_YCBCR_PLANAR:
 431         case LIVE_INPUT_BGRA: {
 432                 bool deinterlace = (chosen_type == LIVE_INPUT_YCBCR_WITH_DEINTERLACE);
 433                 bool override_bounce = !deinterlace;  // For most chains, this will be fine. Reconsider if we see real problems somewhere; it's better than having the user try to understand it.
 434                 bmusb::PixelFormat pixel_format;
 435                 if (chosen_type == LIVE_INPUT_BGRA) {
 436                         pixel_format = bmusb::PixelFormat_8BitBGRA;
 437                 } else if (chosen_type == LIVE_INPUT_YCBCR_PLANAR) {
 438                         pixel_format = bmusb::PixelFormat_8BitYCbCrPlanar;
 439                 } else if (global_flags.bit_depth > 8) {
 440                         pixel_format = bmusb::PixelFormat_10BitYCbCr;
 441                 } else {
 442                         pixel_format = bmusb::PixelFormat_8BitYCbCr;
 443                 }
 444                 LiveInputWrapper *input = new LiveInputWrapper(theme, instantiation->chain.get(), pixel_format, override_bounce, deinterlace, /*user_connectable=*/true);
 445                 effect = input->get_effect();  // Adds itself to the chain, so no need to call add_effect().
 446                 instantiation->inputs.emplace(block->idx, input);
 447                 break;
 448         }
 449         case IMAGE_INPUT: {
 450                 ImageInput *input = new ImageInput;
 451                 instantiation->chain->add_input(input);
 452                 instantiation->image_inputs.emplace(block->idx, input);
 453                 effect = input;
 454                 break;
 455         }
 456         default:
 457                 effect = instantiate_effect(instantiation->chain.get(), chosen_type);
 458                 instantiation->chain->add_effect(effect, inputs);
 459                 break;
 460         }
 461         instantiation->effects.emplace(block->idx, effect);
 462         return effect;
 463 }
 464
 465 int Scene::finalize(lua_State* L)
 466 {
 467         bool only_one_mode = false;
 468         bool chosen_mode = false;
 469         if (lua_gettop(L) == 2) {
 470                 only_one_mode = true;
 471                 chosen_mode = checkbool(L, 2);
 472         } else {
 473                 assert(lua_gettop(L) == 1);
 474         }
 475         Scene *scene = (Scene *)luaL_checkudata(L, 1, "Scene");
 476         Theme *theme = get_theme_updata(L);
 477
 478         size_t base = 1;
 479         for (Block *block : scene->blocks) {
 480                 block->cardinality_base = base;
 481                 base *= block->alternatives.size();
 482         }
 483
 484         const size_t cardinality = base;
 485         size_t real_cardinality = 0;
 486         for (size_t chain_idx = 0; chain_idx < cardinality; ++chain_idx) {
 487                 if (!scene->is_noncanonical_chain(chain_idx)) {
 488                         ++real_cardinality;
 489                 }
 490         }
 491         const size_t total_cardinality = real_cardinality * (only_one_mode ? 1 : 2);
 492         if (total_cardinality > 400) {
 493                 print_warning(L, "The given Scene will instantiate %zu different versions. This will take a lot of time and RAM to compile; see if you could limit some options by e.g. locking the input type in some cases (by giving a fixed input to add_input()).\n",
 494                         total_cardinality);
 495         }
 496
 497         Block *output_block = scene->blocks.back();
 498         for (bool is_main_chain : { false, true }) {
 499                 for (size_t chain_idx = 0; chain_idx < cardinality; ++chain_idx) {
 500                         if ((only_one_mode && is_main_chain != chosen_mode) ||
 501                             scene->is_noncanonical_chain(chain_idx)) {
 502                                 scene->chains.emplace_back();
 503                                 continue;
 504                         }
 505
 506                         Scene::Instantiation instantiation;
 507                         instantiation.chain.reset(new EffectChain(scene->aspect_nom, scene->aspect_denom, theme->get_resource_pool()));
 508                         scene->instantiate_effects(output_block, chain_idx, &instantiation);
 509
 510                         add_outputs_and_finalize(instantiation.chain.get(), is_main_chain);
 511                         scene->chains.emplace_back(move(instantiation));
 512                 }
 513         }
 514         return 0;
 515 }
 516
 517 int find_card_to_connect(Theme *theme, lua_State *L, const Block *block)
 518 {
 519         if (block->signal_type_to_connect == Block::CONNECT_SIGNAL) {
 520                 return theme->map_signal_to_card(block->signal_to_connect);
 521 #ifdef HAVE_CEF
 522         } else if (block->signal_type_to_connect == Block::CONNECT_CEF) {
 523                 return block->cef_to_connect->get_card_index();
 524 #endif
 525         } else if (block->signal_type_to_connect == Block::CONNECT_VIDEO) {
 526                 return block->video_to_connect->get_card_index();
 527         } else if (block->signal_type_to_connect == Block::CONNECT_NONE) {
 528                 luaL_error(L, "An input in a scene was not connected to anything (forgot to call display())");
 529         } else {
 530                 assert(false);
 531         }
 532         return -1;
 533 }
 534
 535 std::pair<movit::EffectChain *, std::function<void()>>
 536 Scene::get_chain(Theme *theme, lua_State *L, unsigned num, const InputState &input_state)
 537 {
 538         // For video inputs, pick the right interlaced/progressive version
 539         // based on the current state of the signals.
 540         InputStateInfo info(input_state);
 541         for (Block *block : blocks) {
 542                 if (block->is_input && block->signal_type_to_connect == Block::CONNECT_SIGNAL) {
 543                         int card_index = theme->map_signal_to_card(block->signal_to_connect);
 544                         if (info.last_interlaced[card_index]) {
 545                                 assert(info.last_pixel_format[card_index] == bmusb::PixelFormat_8BitYCbCr ||
 546                                        info.last_pixel_format[card_index] == bmusb::PixelFormat_10BitYCbCr);
 547                                 block->currently_chosen_alternative = find_index_of(block, LIVE_INPUT_YCBCR_WITH_DEINTERLACE);
 548                         } else if (info.last_pixel_format[card_index] == bmusb::PixelFormat_8BitYCbCrPlanar) {
 549                                 block->currently_chosen_alternative = find_index_of(block, LIVE_INPUT_YCBCR_PLANAR);
 550                         } else if (info.last_pixel_format[card_index] == bmusb::PixelFormat_8BitBGRA) {
 551                                 block->currently_chosen_alternative = find_index_of(block, LIVE_INPUT_BGRA);
 552                         } else {
 553                                 block->currently_chosen_alternative = find_index_of(block, LIVE_INPUT_YCBCR);
 554                         }
 555                         if (block->currently_chosen_alternative == -1) {
 556                                 fprintf(stderr, "ERROR: Input connected to a video card pixel format that it was not ready for.\n");
 557                                 abort();
 558                         }
 559                 }
 560         }
 561
 562         // Find all auto white balance blocks, turn on and off the effect as needed,
 563         // and fetch the actual white balance set (it is stored in Theme).
 564         map<Block *, array<float, 3>> white_balance;
 565         for (size_t block_idx = 0; block_idx < blocks.size(); ++block_idx) {
 566                 Block *block = blocks[block_idx];
 567                 const Block *input = block->white_balance_controller_block;
 568                 if (input == nullptr) {
 569                         continue;  // Not an auto white balance block.
 570                 }
 571
 572                 EffectType chosen_type = current_type(input);
 573                 if (chosen_type == IMAGE_INPUT) {
 574                         // Image inputs never get white balance applied.
 575                         block->currently_chosen_alternative = find_index_of(block, IDENTITY_EFFECT);
 576                         continue;
 577                 }
 578
 579                 assert(chosen_type == LIVE_INPUT_YCBCR ||
 580                        chosen_type == LIVE_INPUT_YCBCR_WITH_DEINTERLACE ||
 581                        chosen_type == LIVE_INPUT_YCBCR_PLANAR ||
 582                        chosen_type == LIVE_INPUT_BGRA);
 583                 int card_idx = find_card_to_connect(theme, L, input);
 584                 RGBTriplet wb = theme->get_white_balance_for_card(card_idx);
 585                 if (fabs(wb.r - 1.0) < 1e-3 && fabs(wb.g - 1.0) < 1e-3 && fabs(wb.b - 1.0) < 1e-3) {
 586                         // Neutral white balance.
 587                         block->currently_chosen_alternative = find_index_of(block, IDENTITY_EFFECT);
 588                 } else {
 589                         block->currently_chosen_alternative = find_index_of(block, WHITE_BALANCE_EFFECT);
 590                         white_balance.emplace(block, array<float, 3>{ wb.r, wb.g, wb.b });
 591                 }
 592         }
 593
 594         // Pick out the right chain based on the current selections,
 595         // and snapshot all the set variables so that we can set them
 596         // in the prepare function even if they're being changed by
 597         // the Lua code later.
 598         bool is_main_chain = (num == 0);
 599         size_t chain_idx = compute_chain_number(is_main_chain);
 600         if (is_noncanonical_chain(chain_idx)) {
 601                 // This should be due to promise_to_disable_if_enabled(). Find out what
 602                 // happened, to give the user some help.
 603                 bitset<256> disabled = find_disabled_blocks(chain_idx);
 604                 for (size_t block_idx = 0; block_idx < blocks.size(); ++block_idx) {
 605                         Block *block = blocks[block_idx];
 606                         if (disabled.test(block_idx)) continue;
 607                         for (const Block::Disabler &disabler : block->disablers) {
 608                                 if (disabler.condition == Block::Disabler::DISABLE_IF_OTHER_ENABLED &&
 609                                     !disabled.test(disabler.block_idx)) {
 610                                         fprintf(stderr, "Promise declared at %s violated.\n", disabler.declaration_point.c_str());
 611                                         abort();
 612                                 }
 613                         }
 614                 }
 615                 assert(false);  // Something else happened, seemingly.
 616         }
 617         const Scene::Instantiation &instantiation = chains[chain_idx];
 618         EffectChain *effect_chain = instantiation.chain.get();
 619
 620         map<LiveInputWrapper *, int> cards_to_connect;
 621         map<ImageInput *, string> images_to_select;
 622         map<pair<Effect *, string>, int> int_to_set;
 623         map<pair<Effect *, string>, float> float_to_set;
 624         map<pair<Effect *, string>, array<float, 3>> vec3_to_set;
 625         map<pair<Effect *, string>, array<float, 4>> vec4_to_set;
 626         for (const auto &index_and_input : instantiation.inputs) {
 627                 Block *block = blocks[index_and_input.first];
 628                 EffectType chosen_type = current_type(block);
 629                 if (chosen_type == LIVE_INPUT_YCBCR ||
 630                     chosen_type == LIVE_INPUT_YCBCR_WITH_DEINTERLACE ||
 631                     chosen_type == LIVE_INPUT_YCBCR_PLANAR ||
 632                     chosen_type == LIVE_INPUT_BGRA) {
 633                         LiveInputWrapper *input = index_and_input.second;
 634                         cards_to_connect.emplace(input, find_card_to_connect(theme, L, block));
 635                 }
 636         }
 637         for (const auto &index_and_input : instantiation.image_inputs) {
 638                 Block *block = blocks[index_and_input.first];
 639                 ImageInput *input = index_and_input.second;
 640                 if (current_type(block) == IMAGE_INPUT) {
 641                         images_to_select.emplace(input, block->pathname);
 642                 }
 643         }
 644         for (const auto &index_and_effect : instantiation.effects) {
 645                 Block *block = blocks[index_and_effect.first];
 646                 Effect *effect = index_and_effect.second;
 647
 648                 bool missing_width = (current_type(block) == RESIZE_EFFECT ||
 649                         current_type(block) == RESAMPLE_EFFECT ||
 650                         current_type(block) == PADDING_EFFECT);
 651                 bool missing_height = missing_width;
 652
 653                 // Get the effects currently set on the block.
 654                 if (current_type(block) != IDENTITY_EFFECT) {  // Ignore settings on optional effects.
 655                         if (block->int_parameters.count("width") && block->int_parameters["width"] > 0) {
 656                                 missing_width = false;
 657                         }
 658                         if (block->int_parameters.count("height") && block->int_parameters["height"] > 0) {
 659                                 missing_height = false;
 660                         }
 661                         for (const auto &key_and_tuple : block->int_parameters) {
 662                                 int_to_set.emplace(make_pair(effect, key_and_tuple.first), key_and_tuple.second);
 663                         }
 664                         for (const auto &key_and_tuple : block->float_parameters) {
 665                                 float_to_set.emplace(make_pair(effect, key_and_tuple.first), key_and_tuple.second);
 666                         }
 667                         if (white_balance.count(block)) {
 668                                 vec3_to_set.emplace(make_pair(effect, "neutral_color"), white_balance[block]);
 669                         }
 670                         for (const auto &key_and_tuple : block->vec3_parameters) {
 671                                 vec3_to_set.emplace(make_pair(effect, key_and_tuple.first), key_and_tuple.second);
 672                         }
 673                         for (const auto &key_and_tuple : block->vec4_parameters) {
 674                                 vec4_to_set.emplace(make_pair(effect, key_and_tuple.first), key_and_tuple.second);
 675                         }
 676                 }
 677
 678                 // Parameters set on the blueprint itself override those that are set for the block,
 679                 // so they are set afterwards.
 680                 if (!block->alternatives.empty()) {
 681                         EffectBlueprint *blueprint = block->alternatives[block->currently_chosen_alternative];
 682                         if (blueprint->int_parameters.count("width") && blueprint->int_parameters["width"] > 0) {
 683                                 missing_width = false;
 684                         }
 685                         if (blueprint->int_parameters.count("height") && blueprint->int_parameters["height"] > 0) {
 686                                 missing_height = false;
 687                         }
 688                         for (const auto &key_and_tuple : blueprint->int_parameters) {
 689                                 int_to_set[make_pair(effect, key_and_tuple.first)] = key_and_tuple.second;
 690                         }
 691                         for (const auto &key_and_tuple : blueprint->float_parameters) {
 692                                 float_to_set[make_pair(effect, key_and_tuple.first)] = key_and_tuple.second;
 693                         }
 694                         for (const auto &key_and_tuple : blueprint->vec3_parameters) {
 695                                 vec3_to_set[make_pair(effect, key_and_tuple.first)] = key_and_tuple.second;
 696                         }
 697                         for (const auto &key_and_tuple : blueprint->vec4_parameters) {
 698                                 vec4_to_set[make_pair(effect, key_and_tuple.first)] = key_and_tuple.second;
 699                         }
 700                 }
 701
 702                 if (missing_width || missing_height) {
 703                         fprintf(stderr, "WARNING: Unset or nonpositive width/height for effect declared at %s "
 704                                 "when getting scene for signal %u; setting to 1x1 to avoid crash.\n",
 705                                 block->declaration_point.c_str(), num);
 706                         int_to_set[make_pair(effect, "width")] = 1;
 707                         int_to_set[make_pair(effect, "height")] = 1;
 708                 }
 709         }
 710
 711         lua_pop(L, 1);
 712
 713         auto setup_chain = [L, theme, cards_to_connect, images_to_select, int_to_set, float_to_set, vec3_to_set, vec4_to_set, input_state]{
 714                 lock_guard<mutex> lock(theme->m);
 715
 716                 // Set up state, including connecting cards.
 717                 for (const auto &input_and_card : cards_to_connect) {
 718                         LiveInputWrapper *input = input_and_card.first;
 719                         input->connect_card(input_and_card.second, input_state);
 720                 }
 721                 for (const auto &input_and_filename : images_to_select) {
 722                         input_and_filename.first->switch_image(input_and_filename.second);
 723                 }
 724                 for (const auto &effect_and_key_and_value : int_to_set) {
 725                         Effect *effect = effect_and_key_and_value.first.first;
 726                         const string &key = effect_and_key_and_value.first.second;
 727                         const int value = effect_and_key_and_value.second;
 728                         if (!effect->set_int(key, value)) {
 729                                 luaL_error(L, "Effect refused set_int(\"%s\", %d) (invalid key?)", key.c_str(), value);
 730                         }
 731                 }
 732                 for (const auto &effect_and_key_and_value : float_to_set) {
 733                         Effect *effect = effect_and_key_and_value.first.first;
 734                         const string &key = effect_and_key_and_value.first.second;
 735                         const float value = effect_and_key_and_value.second;
 736                         if (!effect->set_float(key, value)) {
 737                                 luaL_error(L, "Effect refused set_float(\"%s\", %f) (invalid key?)", key.c_str(), value);
 738                         }
 739                 }
 740                 for (const auto &effect_and_key_and_value : vec3_to_set) {
 741                         Effect *effect = effect_and_key_and_value.first.first;
 742                         const string &key = effect_and_key_and_value.first.second;
 743                         const float *value = effect_and_key_and_value.second.data();
 744                         if (!effect->set_vec3(key, value)) {
 745                                 luaL_error(L, "Effect refused set_vec3(\"%s\", %f, %f, %f) (invalid key?)", key.c_str(),
 746                                                 value[0], value[1], value[2]);
 747                         }
 748                 }
 749                 for (const auto &effect_and_key_and_value : vec4_to_set) {
 750                         Effect *effect = effect_and_key_and_value.first.first;
 751                         const string &key = effect_and_key_and_value.first.second;
 752                         const float *value = effect_and_key_and_value.second.data();
 753                         if (!effect->set_vec4(key, value)) {
 754                                 luaL_error(L, "Effect refused set_vec4(\"%s\", %f, %f, %f, %f) (invalid key?)", key.c_str(),
 755                                                 value[0], value[1], value[2], value[3]);
 756                         }
 757                 }
 758         };
 759         return make_pair(effect_chain, move(setup_chain));
 760 }
 761
 762 bool display(Block *block, lua_State *L, int idx)
 763 {
 764         if (lua_isnumber(L, idx)) {
 765                 int signal_idx = luaL_checknumber(L, idx);
 766                 block->signal_type_to_connect = Block::CONNECT_SIGNAL;
 767                 block->signal_to_connect = signal_idx;
 768                 block->currently_chosen_alternative = find_index_of(block, LIVE_INPUT_YCBCR);  // Will be changed to deinterlaced at get_chain() time if needed.
 769                 return true;
 770 #ifdef HAVE_CEF
 771         } else if (luaL_testudata(L, idx, "HTMLInput")) {
 772                 CEFCapture *capture = *(CEFCapture **)luaL_checkudata(L, idx, "HTMLInput");
 773                 block->signal_type_to_connect = Block::CONNECT_CEF;
 774                 block->cef_to_connect = capture;
 775                 block->currently_chosen_alternative = find_index_of(block, LIVE_INPUT_BGRA);
 776                 assert(capture->get_current_pixel_format() == bmusb::PixelFormat_8BitBGRA);
 777                 return true;
 778 #endif
 779         } else if (luaL_testudata(L, idx, "VideoInput")) {
 780                 FFmpegCapture *capture = *(FFmpegCapture **)luaL_checkudata(L, idx, "VideoInput");
 781                 block->signal_type_to_connect = Block::CONNECT_VIDEO;
 782                 block->video_to_connect = capture;
 783                 if (capture->get_current_pixel_format() == bmusb::PixelFormat_8BitYCbCrPlanar) {
 784                         block->currently_chosen_alternative = find_index_of(block, LIVE_INPUT_YCBCR_PLANAR);
 785                 } else {
 786                         assert(capture->get_current_pixel_format() == bmusb::PixelFormat_8BitBGRA);
 787                         block->currently_chosen_alternative = find_index_of(block, LIVE_INPUT_BGRA);
 788                 }
 789                 return true;
 790         } else if (luaL_testudata(L, idx, "ImageInput")) {
 791                 ImageInput *image = *(ImageInput **)luaL_checkudata(L, idx, "ImageInput");
 792                 block->signal_type_to_connect = Block::CONNECT_NONE;
 793                 block->currently_chosen_alternative = find_index_of(block, IMAGE_INPUT);
 794                 block->pathname = image->get_pathname();
 795                 return true;
 796         } else {
 797                 return false;
 798         }
 799 }
 800
 801 int Block_display(lua_State* L)
 802 {
 803         assert(lua_gettop(L) == 2);
 804         Block *block = *(Block **)luaL_checkudata(L, 1, "Block");
 805         if (!block->is_input) {
 806                 luaL_error(L, "display() called on something that isn't an input");
 807         }
 808
 809         bool ok = display(block, L, 2);
 810         if (!ok) {
 811                 luaL_error(L, "display() called with something that's not a signal (a signal number, a HTML input, or a VideoInput)");
 812         }
 813
 814         if (block->currently_chosen_alternative == -1) {
 815                 luaL_error(L, "display() called on an input whose type was fixed at construction time, with a signal of different type");
 816         }
 817
 818         return 0;
 819 }
 820
 821 int Block_choose(lua_State* L)
 822 {
 823         assert(lua_gettop(L) == 2);
 824         Block *block = *(Block **)luaL_checkudata(L, 1, "Block");
 825         int alternative_idx = -1;
 826         if (lua_isnumber(L, 2)) {
 827                 alternative_idx = luaL_checknumber(L, 2);
 828         } else if (lua_istable(L, 2)) {
 829                 // See if it's an Effect metatable (e.g. foo:choose(ResampleEffect))
 830                 lua_getfield(L, 2, "__effect_type_id");
 831                 if (lua_isnumber(L, -1)) {
 832                         EffectType effect_type = EffectType(luaL_checknumber(L, -1));
 833                         alternative_idx = find_index_of(block, effect_type);
 834                 }
 835                 lua_pop(L, 1);
 836         }
 837
 838         if (alternative_idx == -1) {
 839                 luaL_error(L, "choose() called with something that was not an index or an effect type (e.g. ResampleEffect) that was part of the alternatives");
 840         }
 841
 842         assert(alternative_idx >= 0);
 843         assert(size_t(alternative_idx) < block->alternatives.size());
 844         block->currently_chosen_alternative = alternative_idx;
 845
 846         return wrap_lua_existing_object_nonowned<EffectBlueprint>(L, "EffectBlueprint", block->alternatives[alternative_idx]);
 847 }
 848
 849 int Block_enable(lua_State *L)
 850 {
 851         assert(lua_gettop(L) == 1);
 852         Block *block = *(Block **)luaL_checkudata(L, 1, "Block");
 853
 854         if (block->alternatives.size() != 2 ||
 855             block->alternatives[1]->effect_type != IDENTITY_EFFECT) {
 856                 luaL_error(L, "enable() called on something that wasn't added with add_optional_effect()");
 857         }
 858         block->currently_chosen_alternative = 0;  // The actual effect.
 859         return 0;
 860 }
 861
 862 int Block_enable_if(lua_State *L)
 863 {
 864         assert(lua_gettop(L) == 2);
 865         Block *block = *(Block **)luaL_checkudata(L, 1, "Block");
 866
 867         if (block->alternatives.size() != 2 ||
 868             block->alternatives[1]->effect_type != IDENTITY_EFFECT) {
 869                 luaL_error(L, "enable_if() called on something that wasn't added with add_optional_effect()");
 870         }
 871         bool enabled = checkbool(L, 2);
 872         block->currently_chosen_alternative = enabled ? 0 : 1;
 873         return 0;
 874 }
 875
 876 int Block_disable(lua_State *L)
 877 {
 878         assert(lua_gettop(L) == 1);
 879         Block *block = *(Block **)luaL_checkudata(L, 1, "Block");
 880
 881         block->currently_chosen_alternative = find_index_of(block, IDENTITY_EFFECT);
 882         if (block->currently_chosen_alternative == -1) {
 883                 luaL_error(L, "disable() called on something that didn't have an IdentityEffect fallback (try add_optional_effect())");
 884         }
 885         assert(block->currently_chosen_alternative != -1);
 886         return 0;
 887 }
 888
 889 int Block_always_disable_if_disabled(lua_State *L)
 890 {
 891         assert(lua_gettop(L) == 2);
 892         Block *block = *(Block **)luaL_checkudata(L, 1, "Block");
 893         Block *disabler_block = *(Block **)luaL_checkudata(L, 2, "Block");
 894
 895         int my_alternative = find_index_of(block, IDENTITY_EFFECT);
 896         int their_alternative = find_index_of(disabler_block, IDENTITY_EFFECT);
 897         if (my_alternative == -1) {
 898                 luaL_error(L, "always_disable_if_disabled() called on something that didn't have an IdentityEffect fallback (try add_optional_effect())");
 899         }
 900         if (their_alternative == -1) {
 901                 luaL_error(L, "always_disable_if_disabled() with an argument that didn't have an IdentityEffect fallback (try add_optional_effect())");
 902         }
 903
 904         // The declaration point isn't actually used, but it's nice for completeness.
 905         block->disablers.push_back(Block::Disabler{ disabler_block->idx, Block::Disabler::DISABLE_IF_OTHER_DISABLED, get_declaration_point(L) });
 906
 907         lua_pop(L, 2);
 908         return 0;
 909 }
 910
 911 int Block_promise_to_disable_if_enabled(lua_State *L)
 912 {
 913         assert(lua_gettop(L) == 2);
 914         Block *block = *(Block **)luaL_checkudata(L, 1, "Block");
 915         Block *disabler_block = *(Block **)luaL_checkudata(L, 2, "Block");
 916
 917         int my_alternative = find_index_of(block, IDENTITY_EFFECT);
 918         int their_alternative = find_index_of(disabler_block, IDENTITY_EFFECT);
 919         if (my_alternative == -1) {
 920                 luaL_error(L, "promise_to_disable_if_enabled() called on something that didn't have an IdentityEffect fallback (try add_optional_effect())");
 921         }
 922         if (their_alternative == -1) {
 923                 luaL_error(L, "promise_to_disable_if_enabled() with an argument that didn't have an IdentityEffect fallback (try add_optional_effect())");
 924         }
 925
 926         block->disablers.push_back(Block::Disabler{ disabler_block->idx, Block::Disabler::DISABLE_IF_OTHER_ENABLED, get_declaration_point(L) });
 927
 928         lua_pop(L, 2);
 929         return 0;
 930 }
 931
 932 int Block_set_int(lua_State *L)
 933 {
 934         assert(lua_gettop(L) == 3);
 935         Block *block = *(Block **)luaL_checkudata(L, 1, "Block");
 936         string key = checkstdstring(L, 2);
 937         float value = luaL_checknumber(L, 3);
 938
 939         // TODO: check validity already here, if possible?
 940         block->int_parameters[key] = value;
 941
 942         return 0;
 943 }
 944
 945 int Block_set_float(lua_State *L)
 946 {
 947         assert(lua_gettop(L) == 3);
 948         Block *block = *(Block **)luaL_checkudata(L, 1, "Block");
 949         string key = checkstdstring(L, 2);
 950         float value = luaL_checknumber(L, 3);
 951
 952         // TODO: check validity already here, if possible?
 953         block->float_parameters[key] = value;
 954
 955         return 0;
 956 }
 957
 958 int Block_set_vec3(lua_State *L)
 959 {
 960         assert(lua_gettop(L) == 5);
 961         Block *block = *(Block **)luaL_checkudata(L, 1, "Block");
 962         string key = checkstdstring(L, 2);
 963         array<float, 3> v;
 964         v[0] = luaL_checknumber(L, 3);
 965         v[1] = luaL_checknumber(L, 4);
 966         v[2] = luaL_checknumber(L, 5);
 967
 968         // TODO: check validity already here, if possible?
 969         block->vec3_parameters[key] = v;
 970
 971         return 0;
 972 }
 973
 974 int Block_set_vec4(lua_State *L)
 975 {
 976         assert(lua_gettop(L) == 6);
 977         Block *block = *(Block **)luaL_checkudata(L, 1, "Block");
 978         string key = checkstdstring(L, 2);
 979         array<float, 4> v;
 980         v[0] = luaL_checknumber(L, 3);
 981         v[1] = luaL_checknumber(L, 4);
 982         v[2] = luaL_checknumber(L, 5);
 983         v[3] = luaL_checknumber(L, 6);
 984
 985         // TODO: check validity already here, if possible?
 986         block->vec4_parameters[key] = v;
 987
 988         return 0;
 989 }
 990