src/game/level/level_editor/rect_layer.c

   1 #include <float.h>
   2 #include <errno.h>
   3
   4 #include "game/camera.h"
   5 #include "system/stacktrace.h"
   6 #include "system/nth_alloc.h"
   7 #include "system/log.h"
   8 #include "math/rect.h"
   9 #include "color.h"
  10 #include "rect_layer.h"
  11 #include "dynarray.h"
  12 #include "system/str.h"
  13 #include "undo_history.h"
  14 #include "game/level/action.h"
  15 #include "game.h"
  16 #include "math/extrema.h"
  17
  18 #define RECT_LAYER_SELECTION_THICCNESS 15.0f
  19 #define RECT_LAYER_ID_LABEL_SIZE vec(3.0f, 3.0f)
  20 #define CREATE_AREA_THRESHOLD 10.0
  21
  22 static int rect_clipboard = 0;
  23 static Rect rect_clipboard_rect;
  24 static Color rect_clipboard_color;
  25
  26 static Cursor_Style resize_styles[1 << RECT_SIDE_N] = {
  27     0,                         // [0]
  28     CURSOR_STYLE_RESIZE_VERT,  // [1]
  29     CURSOR_STYLE_RESIZE_HORIS, // [2]
  30     CURSOR_STYLE_RESIZE_DIAG1, // [3]
  31     CURSOR_STYLE_RESIZE_VERT,  // [4]
  32     0,                         // [5]
  33     CURSOR_STYLE_RESIZE_DIAG2, // [6]
  34     0,                         // [7]
  35     CURSOR_STYLE_RESIZE_HORIS, // [8]
  36     CURSOR_STYLE_RESIZE_DIAG2, // [9]
  37     0,                         // [10]
  38     0,                         // [11]
  39     CURSOR_STYLE_RESIZE_DIAG1  // [12]
  40 };
  41
  42 typedef enum {
  43     RECT_UNDO_ADD,
  44     RECT_UNDO_DELETE,
  45     RECT_UNDO_UPDATE,
  46     RECT_UNDO_SWAP
  47 } RectUndoType;
  48
  49 // Delete, Update
  50 typedef struct {
  51     RectUndoType type;
  52     RectLayer *layer;
  53     size_t index;
  54     Rect rect;
  55     Color color;
  56     Action action;
  57     char id[ENTITY_MAX_ID_SIZE];
  58 } UndoElementContext;
  59
  60 // Add
  61 typedef struct {
  62     RectUndoType type;
  63     RectLayer *layer;
  64     size_t index;
  65 } UndoAddContext;
  66
  67 // Swap
  68 typedef struct {
  69     RectUndoType type;
  70     RectLayer *layer;
  71     size_t index1;
  72     size_t index2;
  73 } UndoSwapContext;
  74
  75 typedef union {
  76     RectUndoType type;
  77     UndoAddContext add;
  78     UndoElementContext element;
  79     UndoSwapContext swap;
  80 } RectUndoContext;
  81
  82 static
  83 RectUndoContext create_rect_undo_add_context(RectLayer *layer, size_t index)
  84 {
  85     trace_assert(layer);
  86     trace_assert(index < layer->rects.count);
  87
  88     RectUndoContext undo_context;
  89     undo_context.add.type = RECT_UNDO_ADD;
  90     undo_context.add.layer = layer;
  91     undo_context.add.index = index;
  92     return undo_context;
  93 }
  94
  95 static
  96 RectUndoContext create_rect_undo_element_context(RectLayer *layer)
  97 {
  98     trace_assert(layer);
  99     size_t index = (size_t) layer->selection;
 100     trace_assert(index < layer->rects.count);
 101
 102     RectUndoContext undo_context;
 103     undo_context.element.layer = layer;
 104     undo_context.element.index = index;
 105     dynarray_copy_to(&layer->rects, &undo_context.element.rect, index);
 106     dynarray_copy_to(&layer->colors, &undo_context.element.color, index);
 107     dynarray_copy_to(&layer->ids, undo_context.element.id, index);
 108     dynarray_copy_to(&layer->actions, &undo_context.element.action, index);
 109     return undo_context;
 110 }
 111
 112 static
 113 RectUndoContext create_rect_undo_update_context(RectLayer *rect_layer)
 114 {
 115     RectUndoContext undo_context = create_rect_undo_element_context(rect_layer);
 116     undo_context.type = RECT_UNDO_UPDATE;
 117     return undo_context;
 118 }
 119
 120 static
 121 RectUndoContext create_rect_undo_delete_context(RectLayer *rect_layer)
 122 {
 123     RectUndoContext undo_context = create_rect_undo_element_context(rect_layer);
 124     undo_context.type = RECT_UNDO_DELETE;
 125     return undo_context;
 126 }
 127
 128 static
 129 RectUndoContext create_rect_undo_swap_context(RectLayer *rect_layer, size_t index1, size_t index2)
 130 {
 131     RectUndoContext undo_context;
 132     undo_context.swap.type = RECT_UNDO_SWAP;
 133     undo_context.swap.layer = rect_layer;
 134     undo_context.swap.index1 = index1;
 135     undo_context.swap.index2 = index2;
 136     return undo_context;
 137 }
 138
 139 static
 140 void rect_layer_undo(void *context, size_t context_size)
 141 {
 142     trace_assert(context);
 143     trace_assert(sizeof(RectUndoContext) == context_size);
 144
 145     RectUndoContext *undo_context = context;
 146
 147     switch (undo_context->type) {
 148     case RECT_UNDO_ADD: {
 149         RectLayer *layer = undo_context->add.layer;
 150         dynarray_delete_at(&layer->rects, undo_context->add.index);
 151         dynarray_delete_at(&layer->colors, undo_context->add.index);
 152         dynarray_delete_at(&layer->ids, undo_context->add.index);
 153         dynarray_delete_at(&layer->actions, undo_context->add.index);
 154         layer->selection = -1;
 155     } break;
 156
 157     case RECT_UNDO_DELETE: {
 158         RectLayer *layer = undo_context->element.layer;
 159         dynarray_insert_before(&layer->rects, undo_context->element.index, &undo_context->element.rect);
 160         dynarray_insert_before(&layer->colors, undo_context->element.index, &undo_context->element.color);
 161         dynarray_insert_before(&layer->ids, undo_context->element.index, &undo_context->element.id);
 162         dynarray_insert_before(&layer->actions, undo_context->element.index, &undo_context->element.action);
 163         layer->selection = -1;
 164     } break;
 165
 166     case RECT_UNDO_UPDATE: {
 167         RectLayer *layer = undo_context->element.layer;
 168         dynarray_replace_at(&layer->rects, undo_context->element.index, &undo_context->element.rect);
 169         dynarray_replace_at(&layer->colors, undo_context->element.index, &undo_context->element.color);
 170         dynarray_replace_at(&layer->ids, undo_context->element.index, &undo_context->element.id);
 171         dynarray_replace_at(&layer->actions, undo_context->element.index, &undo_context->element.action);
 172     } break;
 173
 174     case RECT_UNDO_SWAP: {
 175         RectLayer *layer = undo_context->element.layer;
 176         dynarray_swap(&layer->rects, undo_context->swap.index1, undo_context->swap.index2);
 177         dynarray_swap(&layer->colors, undo_context->swap.index1, undo_context->swap.index2);
 178         dynarray_swap(&layer->ids, undo_context->swap.index1, undo_context->swap.index2);
 179         dynarray_swap(&layer->actions, undo_context->swap.index1, undo_context->swap.index2);
 180     } break;
 181     }
 182 }
 183
 184 #define RECT_UNDO_PUSH(HISTORY, CONTEXT)                                     \
 185     do {                                                                \
 186         RectUndoContext context = (CONTEXT);                                \
 187         undo_history_push(                                              \
 188             HISTORY,                                                    \
 189             rect_layer_undo,                                            \
 190             &context,                                                   \
 191             sizeof(context));                                           \
 192     } while(0)
 193
 194 static int rect_layer_add_rect(RectLayer *layer,
 195                                Rect rect,
 196                                Color color,
 197                                UndoHistory *undo_history)
 198 {
 199     trace_assert(layer);
 200
 201     dynarray_push(&layer->rects, &rect);
 202     dynarray_push(&layer->colors, &color);
 203
 204     char id[ENTITY_MAX_ID_SIZE];
 205     snprintf(id, ENTITY_MAX_ID_SIZE, "%s_%d",
 206              layer->id_name_prefix,
 207              layer->id_name_counter++);
 208     dynarray_push(&layer->ids, id);
 209
 210     dynarray_push_empty(&layer->actions);
 211
 212     RECT_UNDO_PUSH(
 213         undo_history,
 214         create_rect_undo_add_context(
 215             layer,
 216             layer->rects.count - 1));
 217
 218     return 0;
 219 }
 220
 221 static int rect_layer_rect_at(RectLayer *layer, Vec2f position)
 222 {
 223     trace_assert(layer);
 224
 225     int n = (int) layer->rects.count;
 226     Rect *rects = (Rect*)layer->rects.data;
 227
 228     for (int i = n - 1; i >= 0; --i) {
 229         if (rect_contains_point(rects[i], position)) {
 230             return (int) i;
 231         }
 232     }
 233
 234     return -1;
 235 }
 236
 237 static void rect_layer_swap_elements(RectLayer *layer, size_t a, size_t b,
 238                                      UndoHistory *undo_history)
 239 {
 240     trace_assert(layer);
 241     trace_assert(a < layer->rects.count);
 242     trace_assert(b < layer->rects.count);
 243
 244     dynarray_swap(&layer->rects, a, b);
 245     dynarray_swap(&layer->colors, a, b);
 246     dynarray_swap(&layer->ids, a, b);
 247     dynarray_swap(&layer->actions, a, b);
 248
 249     RECT_UNDO_PUSH(undo_history, create_rect_undo_swap_context(layer, a, b));
 250 }
 251
 252 static int rect_layer_delete_rect_at(RectLayer *layer,
 253                                      size_t i,
 254                                      UndoHistory *undo_history)
 255 {
 256     trace_assert(layer);
 257
 258     RECT_UNDO_PUSH(undo_history, create_rect_undo_delete_context(layer));
 259
 260     dynarray_delete_at(&layer->rects, i);
 261     dynarray_delete_at(&layer->colors, i);
 262     dynarray_delete_at(&layer->ids, i);
 263     dynarray_delete_at(&layer->actions, i);
 264
 265     return 0;
 266 }
 267
 268 static int calc_resize_mask(Vec2f point, Rect rect)
 269 {
 270     int mask = 0;
 271     for (Rect_side side = 0; side < RECT_SIDE_N; ++side) {
 272         if (rect_side_distance(rect, point, side) < RECT_LAYER_SELECTION_THICCNESS) {
 273             mask = mask | (1 << side);
 274         }
 275     }
 276     return mask;
 277 }
 278
 279 static int rect_layer_event_idle(RectLayer *layer,
 280                                  const SDL_Event *event,
 281                                  const Camera *camera,
 282                                  UndoHistory *undo_history)
 283 {
 284     trace_assert(layer);
 285     trace_assert(event);
 286     trace_assert(camera);
 287
 288     int color_changed = 0;
 289     if (color_picker_event(&layer->color_picker, event, camera, &color_changed) < 0) {
 290         return -1;
 291     }
 292
 293     if (color_changed) {
 294         if (layer->selection >= 0) {
 295             dynarray_copy_to(&layer->colors, &layer->inter_color, (size_t)layer->selection);
 296             layer->state = RECT_LAYER_RECOLOR;
 297         }
 298         return 0;
 299     }
 300
 301     Rect *rects = (Rect*)layer->rects.data;
 302
 303     switch (event->type) {
 304     case SDL_MOUSEBUTTONDOWN: {
 305         switch (event->button.button) {
 306         case SDL_BUTTON_LEFT: {
 307             Vec2f position = camera_map_screen(
 308                 camera,
 309                 event->button.x,
 310                 event->button.y);
 311             int rect_at_position =
 312                 rect_layer_rect_at(layer, position);
 313
 314
 315             Color *colors = (Color*)layer->colors.data;
 316
 317             if (layer->selection >= 0 &&
 318                 layer->selection == rect_at_position &&
 319                 (layer->resize_mask = calc_resize_mask(
 320                     vec((float) event->button.x, (float)event->button.y),
 321                     camera_rect(camera, rects[layer->selection])))) {
 322                 layer->state = RECT_LAYER_RESIZE;
 323                 dynarray_copy_to(&layer->rects, &layer->inter_rect, (size_t) layer->selection);
 324             } else if (rect_at_position >= 0) {
 325                 layer->selection = rect_at_position;
 326                 layer->state = RECT_LAYER_MOVE;
 327                 layer->move_anchor = vec_sub(
 328                     position,
 329                     vec(
 330                         rects[layer->selection].x,
 331                         rects[layer->selection].y));
 332                 layer->color_picker =
 333                     create_color_picker_from_rgba(colors[rect_at_position]);
 334                 dynarray_copy_to(&layer->rects, &layer->inter_rect, (size_t) rect_at_position);
 335             } else {
 336                 layer->selection = rect_at_position;
 337
 338                 if (layer->selection < 0) {
 339                     layer->state = RECT_LAYER_CREATE;
 340                     layer->create_begin = position;
 341                     layer->create_end = position;
 342                 }
 343             }
 344         } break;
 345         }
 346     } break;
 347
 348     case SDL_MOUSEMOTION: {
 349         int resize_mask = 0;
 350         Vec2f position = camera_map_screen(
 351             camera,
 352             event->button.x,
 353             event->button.y);
 354         if (layer->selection >= 0 &&
 355             layer->selection == rect_layer_rect_at(layer, position) &&
 356             (resize_mask = calc_resize_mask(
 357                 vec((float) event->button.x, (float)event->button.y),
 358                 camera_rect(camera, rects[layer->selection])))) {
 359             layer->cursor->style = resize_styles[resize_mask];
 360         } else {
 361             layer->cursor->style = CURSOR_STYLE_POINTER;
 362         }
 363     } break;
 364
 365     case SDL_KEYDOWN: {
 366         switch (event->key.keysym.sym) {
 367         case SDLK_UP: {
 368             if ((event->key.keysym.mod & KMOD_SHIFT)
 369                 && (layer->selection >= 0)
 370                 && ((size_t)(layer->selection + 1) < layer->rects.count)) {
 371                 rect_layer_swap_elements(
 372                     layer,
 373                     (size_t) layer->selection,
 374                     (size_t) layer->selection + 1,
 375                     undo_history);
 376                 layer->selection++;
 377             }
 378         } break;
 379
 380         case SDLK_DOWN: {
 381             if ((event->key.keysym.mod & KMOD_SHIFT)
 382                 && (layer->selection > 0)
 383                 && ((size_t) layer->selection < layer->rects.count)) {
 384                 rect_layer_swap_elements(
 385                     layer,
 386                     (size_t) layer->selection,
 387                     (size_t) layer->selection - 1,
 388                     undo_history);
 389                 layer->selection--;
 390             }
 391         } break;
 392
 393         case SDLK_DELETE: {
 394             if (layer->selection >= 0) {
 395                 rect_layer_delete_rect_at(layer, (size_t) layer->selection, undo_history);
 396                 layer->selection = -1;
 397             }
 398         } break;
 399
 400         case SDLK_q: {
 401             // TODO(#1171): there is no UI indication that we are in the snapping mode
 402             layer->snapping_enabled = !layer->snapping_enabled;
 403         } break;
 404
 405         case SDLK_F2: {
 406             if (layer->selection >= 0) {
 407                 const char *ids = (char*)layer->ids.data;
 408                 Color *colors = (Color*)layer->colors.data;
 409
 410                 edit_field_restyle(
 411                     &layer->id_edit_field,
 412                     RECT_LAYER_ID_LABEL_SIZE,
 413                     color_invert(colors[layer->selection]));
 414
 415                 layer->state = RECT_LAYER_ID_RENAME;
 416                 edit_field_replace(
 417                     &layer->id_edit_field,
 418                     ids + layer->selection * ENTITY_MAX_ID_SIZE);
 419                 SDL_StartTextInput();
 420             }
 421         } break;
 422
 423         case SDLK_c: {
 424             if ((event->key.keysym.mod & KMOD_LCTRL) && layer->selection >= 0) {
 425                 rect_clipboard = 1;
 426                 dynarray_copy_to(&layer->rects, &rect_clipboard_rect, (size_t)layer->selection);
 427                 dynarray_copy_to(&layer->colors, &rect_clipboard_color, (size_t)layer->selection);
 428             }
 429         } break;
 430
 431         case SDLK_v: {
 432             if ((event->key.keysym.mod & KMOD_LCTRL) && rect_clipboard) {
 433                 int x, y;
 434                 SDL_GetMouseState(&x, &y);
 435                 Vec2f position = camera_map_screen(camera, x, y);
 436
 437                 rect_layer_add_rect(
 438                     layer,
 439                     rect(position.x, position.y,
 440                          rect_clipboard_rect.w, rect_clipboard_rect.h),
 441                     rect_clipboard_color,
 442                     undo_history);
 443             }
 444         } break;
 445         }
 446     } break;
 447     }
 448
 449     return 0;
 450 }
 451
 452 static int rect_layer_event_create(RectLayer *layer,
 453                                    const SDL_Event *event,
 454                                    const Camera *camera,
 455                                    UndoHistory *undo_history)
 456 {
 457     trace_assert(layer);
 458     trace_assert(event);
 459     trace_assert(camera);
 460
 461     switch (event->type) {
 462     case SDL_MOUSEBUTTONUP: {
 463         switch (event->button.button) {
 464         case SDL_BUTTON_LEFT: {
 465             const Rect real_rect =
 466                 rect_from_points(
 467                     layer->create_begin,
 468                     layer->create_end);
 469             const float area = real_rect.w * real_rect.h;
 470
 471             if (area >= CREATE_AREA_THRESHOLD) {
 472                 rect_layer_add_rect(
 473                     layer,
 474                     real_rect,
 475                     color_picker_rgba(&layer->color_picker),
 476                     undo_history);
 477             } else {
 478                 log_info("The area is too small %f. Such small box won't be created.\n", area);
 479             }
 480             layer->state = RECT_LAYER_IDLE;
 481         } break;
 482         }
 483     } break;
 484
 485     case SDL_MOUSEMOTION: {
 486         layer->create_end = camera_map_screen(
 487             camera,
 488             event->motion.x,
 489             event->motion.y);
 490     } break;
 491     }
 492     return 0;
 493 }
 494
 495 static
 496 void snap_rect_resize_if_enabled(RectLayer *layer, Rect *a, float snapping_threshold)
 497 {
 498     trace_assert(layer);
 499     trace_assert(layer->selection >= 0);
 500     trace_assert(a);
 501
 502     if (!layer->snapping_enabled) return;
 503
 504     Rect *rects = (Rect*)layer->rects.data;
 505     size_t rects_size = layer->rects.count;
 506
 507     for (size_t i = 0; i < rects_size; ++i) {
 508         if (i == (size_t) layer->selection) continue;
 509
 510         const Rect b = rects[i];
 511
 512         if (segment_overlap(vec(a->x, a->x + a->w), vec(b.x, b.x + b.w))) {
 513             snap_var2seg(&a->y, b.y, 0, b.h, snapping_threshold);
 514         }
 515
 516         if (segment_overlap(vec(a->y, a->y + a->h), vec(b.y, b.y + b.h))) {
 517             snap_var2seg(&a->x, b.x, 0, b.w, snapping_threshold);
 518         }
 519     }
 520 }
 521
 522 static int rect_layer_event_resize(RectLayer *layer,
 523                                    const SDL_Event *event,
 524                                    const Camera *camera,
 525                                    UndoHistory *undo_history)
 526 {
 527     trace_assert(layer);
 528     trace_assert(event);
 529     trace_assert(camera);
 530     trace_assert(layer->selection >= 0);
 531
 532     Rect *rects = (Rect*)layer->rects.data;
 533
 534     float scaled_snap_threshold = SNAPPING_THRESHOLD / camera->scale;
 535
 536     switch (event->type) {
 537     case SDL_MOUSEMOTION: {
 538         Vec2f position = camera_map_screen(
 539             camera,
 540             event->button.x,
 541             event->button.y);
 542
 543         switch (layer->resize_mask) {
 544         case 1: {               // TOP
 545             Rect a = rect(rects[layer->selection].x,
 546                           position.y,
 547                           rects[layer->selection].w,
 548                           rects[layer->selection].h);
 549
 550             snap_rect_resize_if_enabled(layer, &a, scaled_snap_threshold);
 551
 552             layer->inter_rect = rect_from_points(
 553                 vec(a.x, a.y),
 554                 rect_position2(rects[layer->selection]));
 555         } break;
 556
 557         case 2: {               // LEFT
 558             Rect a = rect(position.x,
 559                           rects[layer->selection].y,
 560                           rects[layer->selection].w,
 561                           rects[layer->selection].h);
 562
 563             snap_rect_resize_if_enabled(layer, &a, scaled_snap_threshold);
 564
 565             layer->inter_rect = rect_from_points(
 566                 vec(a.x, a.y),
 567                 rect_position2(rects[layer->selection]));
 568         } break;
 569
 570         case 3: {               // TOP,LEFT
 571             Rect a = rect(
 572                 position.x,
 573                 position.y,
 574                 rects[layer->selection].w,
 575                 rects[layer->selection].h);
 576
 577             snap_rect_resize_if_enabled(layer, &a, scaled_snap_threshold);
 578
 579             layer->inter_rect = rect_from_points(
 580                 vec(a.x, a.y),
 581                 rect_position2(rects[layer->selection]));
 582         } break;
 583
 584         case 4: {               // BOTTOM
 585             Rect a = rect(rects[layer->selection].x,
 586                           position.y,
 587                           rects[layer->selection].w,
 588                           rects[layer->selection].h);
 589
 590             snap_rect_resize_if_enabled(layer, &a, scaled_snap_threshold);
 591
 592             layer->inter_rect = rect_from_points(
 593                 rect_position(rects[layer->selection]),
 594                 vec(rects[layer->selection].x + rects[layer->selection].w,
 595                     a.y));
 596         } break;
 597
 598         case 6: {               // BOTTOM,LEFT
 599             Rect a = rect(
 600                 position.x,
 601                 position.y,
 602                 rects[layer->selection].w,
 603                 -rects[layer->selection].h);
 604
 605             snap_rect_resize_if_enabled(layer, &a, scaled_snap_threshold);
 606
 607             layer->inter_rect = rect_from_points(
 608                 vec(a.x, rects[layer->selection].y),
 609                 vec(rects[layer->selection].x + rects[layer->selection].w,
 610                     a.y));
 611         } break;
 612
 613         case 8: {               // RIGHT
 614             Rect a = rect(position.x,
 615                           rects[layer->selection].y,
 616                           rects[layer->selection].w,
 617                           rects[layer->selection].h);
 618
 619             snap_rect_resize_if_enabled(layer, &a, scaled_snap_threshold);
 620
 621             layer->inter_rect = rect_from_points(
 622                 rect_position(rects[layer->selection]),
 623                 vec(a.x, rects[layer->selection].y + rects[layer->selection].h));
 624         } break;
 625
 626         case 9: {               // TOP,RIGHT
 627             Rect a = rect(
 628                 position.x,
 629                 position.y,
 630                 -rects[layer->selection].w,
 631                 rects[layer->selection].h);
 632
 633             snap_rect_resize_if_enabled(layer, &a, scaled_snap_threshold);
 634
 635             layer->inter_rect = rect_from_points(
 636                 vec(rects[layer->selection].x, a.y),
 637                 vec(a.x,
 638                     rects[layer->selection].y + rects[layer->selection].h));
 639         } break;
 640
 641         case 12: {              // BOTTOM,RIGHT
 642             Rect a = rect(
 643                 position.x,
 644                 position.y,
 645                 -rects[layer->selection].w,
 646                 -rects[layer->selection].h);
 647
 648             snap_rect_resize_if_enabled(layer, &a, scaled_snap_threshold);
 649
 650             layer->inter_rect = rect_from_points(
 651                 rect_position(rects[layer->selection]),
 652                 vec(a.x, a.y));
 653         } break;
 654         }
 655
 656     } break;
 657
 658     case SDL_MOUSEBUTTONUP: {
 659         layer->state = RECT_LAYER_IDLE;
 660         RECT_UNDO_PUSH(undo_history, create_rect_undo_update_context(layer));
 661         dynarray_replace_at(&layer->rects, (size_t) layer->selection, &layer->inter_rect);
 662     } break;
 663     }
 664
 665     return 0;
 666 }
 667
 668 static
 669 void snap_rect_move_if_enabled(RectLayer *layer, Rect *a,
 670                                float snapping_threshold)
 671 {
 672     trace_assert(a);
 673     trace_assert(layer);
 674     trace_assert(layer->selection >= 0);
 675
 676     if (!layer->snapping_enabled) return;
 677
 678     Rect *rects = (Rect*)layer->rects.data;
 679     size_t rects_size = layer->rects.count;
 680
 681     for (size_t i = 0; i < rects_size; ++i) {
 682         if (i == (size_t) layer->selection) continue;
 683
 684         const Rect b = rects[i];
 685
 686         if (segment_overlap(vec(a->x, a->x + a->w), vec(b.x,  b.x  + b.w))) {
 687             snap_seg2seg(&a->y, b.y, a->h, b.h, snapping_threshold);
 688         }
 689
 690         if (segment_overlap(vec(a->y, a->y + a->h), vec(b.y,  b.y  + b.h))) {
 691             snap_seg2seg(&a->x, b.x, a->w, b.w, snapping_threshold);
 692         }
 693     }
 694 }
 695
 696 static int rect_layer_event_move(RectLayer *layer,
 697                                  const SDL_Event *event,
 698                                  const Camera *camera,
 699                                  UndoHistory *undo_history)
 700 {
 701     trace_assert(layer);
 702     trace_assert(event);
 703     trace_assert(camera);
 704     trace_assert(layer->selection >= 0);
 705
 706     Rect *rects = (Rect*)layer->rects.data;
 707
 708     switch (event->type) {
 709     case SDL_MOUSEMOTION: {
 710         const Uint8 *state = SDL_GetKeyboardState(NULL);
 711         const Vec2f mouse_pos = vec_sub(
 712             camera_map_screen(
 713                 camera,
 714                 event->button.x,
 715                 event->button.y),
 716             layer->move_anchor);
 717
 718         if (!(state[SDL_SCANCODE_LCTRL] || state[SDL_SCANCODE_RCTRL])) {
 719             layer->inter_rect.x = mouse_pos.x;
 720             layer->inter_rect.y = mouse_pos.y;
 721         } else {
 722             const Vec2f rect_pos = rect_position(rects[layer->selection]);
 723
 724             const float dx = fabsf(rect_pos.x - mouse_pos.x);
 725             const float dy = fabsf(rect_pos.y - mouse_pos.y);
 726
 727             if (dx > dy) {
 728                 layer->inter_rect.x = mouse_pos.x;
 729                 layer->inter_rect.y = rect_pos.y;
 730             } else {
 731                 layer->inter_rect.x = rect_pos.x;
 732                 layer->inter_rect.y = mouse_pos.y;
 733             }
 734         }
 735
 736         snap_rect_move_if_enabled(layer, &layer->inter_rect,
 737                                   SNAPPING_THRESHOLD / camera->scale);
 738     } break;
 739
 740     case SDL_MOUSEBUTTONUP: {
 741         layer->state = RECT_LAYER_IDLE;
 742
 743         float distance = vec_length(
 744             vec_sub(rect_position(layer->inter_rect),
 745                     rect_position(rects[layer->selection])));
 746
 747         if (distance > 1e-6) {
 748             RECT_UNDO_PUSH(undo_history, create_rect_undo_update_context(layer));
 749             dynarray_replace_at(&layer->rects, (size_t) layer->selection, &layer->inter_rect);
 750         }
 751     } break;
 752     }
 753     return 0;
 754 }
 755
 756 static int rect_layer_event_id_rename(RectLayer *layer,
 757                                       const SDL_Event *event,
 758                                       const Camera *camera,
 759                                       UndoHistory *undo_history)
 760 {
 761     trace_assert(layer);
 762     trace_assert(event);
 763     trace_assert(camera);
 764     trace_assert(layer->selection >= 0);
 765
 766     switch (event->type) {
 767     case SDL_KEYDOWN: {
 768         switch (event->key.keysym.sym) {
 769         case SDLK_RETURN: {
 770             RECT_UNDO_PUSH(undo_history, create_rect_undo_update_context(layer));
 771
 772             char *id = dynarray_pointer_at(&layer->ids, (size_t)layer->selection);
 773             memset(id, 0, ENTITY_MAX_ID_SIZE);
 774             memcpy(id, edit_field_as_text(&layer->id_edit_field), ENTITY_MAX_ID_SIZE - 1);
 775             layer->state = RECT_LAYER_IDLE;
 776             SDL_StopTextInput();
 777         } break;
 778
 779         case SDLK_ESCAPE: {
 780             layer->state = RECT_LAYER_IDLE;
 781             SDL_StopTextInput();
 782         } break;
 783         }
 784     } break;
 785     }
 786
 787     return edit_field_event(&layer->id_edit_field, event);
 788 }
 789
 790 LayerPtr rect_layer_as_layer(RectLayer *rect_layer)
 791 {
 792     LayerPtr layer = {
 793         .type = LAYER_RECT,
 794         .ptr = rect_layer
 795     };
 796     return layer;
 797 }
 798
 799 RectLayer *create_rect_layer(Memory *memory,
 800                              const char *id_name_prefix,
 801                              Cursor *cursor)
 802 {
 803     trace_assert(memory);
 804     trace_assert(id_name_prefix);
 805     trace_assert(cursor);
 806
 807     RectLayer *rect_layer = memory_alloc(memory, sizeof(RectLayer));
 808
 809     rect_layer->ids = create_dynarray(memory, sizeof(char) * ENTITY_MAX_ID_SIZE);
 810     rect_layer->rects = create_dynarray(memory, sizeof(Rect));
 811     rect_layer->colors = create_dynarray(memory, sizeof(Color));
 812     rect_layer->actions = create_dynarray(memory, sizeof(Action));
 813     rect_layer->id_edit_field.font_size = RECT_LAYER_ID_LABEL_SIZE;
 814     rect_layer->id_edit_field.font_color = COLOR_BLACK;
 815     rect_layer->color_picker = create_color_picker_from_rgba(rgba(1.0f, 0.0f, 0.0f, 1.0f));
 816     rect_layer->selection = -1;
 817     rect_layer->id_name_prefix = id_name_prefix;
 818     rect_layer->cursor = cursor;
 819
 820     return rect_layer;
 821 }
 822
 823 void rect_layer_load(RectLayer *layer, Memory *memory, String *input)
 824 {
 825     trace_assert(layer);
 826     trace_assert(memory);
 827     trace_assert(input);
 828
 829     int n = atoi(string_to_cstr(memory, trim(chop_by_delim(input, '\n'))));
 830     char id[ENTITY_MAX_ID_SIZE];
 831     for (int i = 0; i < n; ++i) {
 832         Rect rect;
 833         String line = trim(chop_by_delim(input, '\n'));
 834         String string_id = trim(chop_word(&line));
 835         rect.x = strtof(string_to_cstr(memory, trim(chop_word(&line))), NULL);
 836         rect.y = strtof(string_to_cstr(memory, trim(chop_word(&line))), NULL);
 837         rect.w = strtof(string_to_cstr(memory, trim(chop_word(&line))), NULL);
 838         rect.h = strtof(string_to_cstr(memory, trim(chop_word(&line))), NULL);
 839         Color color = hexs(trim(chop_word(&line)));
 840
 841         memset(id, 0, ENTITY_MAX_ID_SIZE);
 842         memcpy(
 843             id,
 844             string_id.data,
 845             min_size_t(ENTITY_MAX_ID_SIZE - 1, string_id.count));
 846
 847         dynarray_push(&layer->rects, &rect);
 848         dynarray_push(&layer->colors, &color);
 849         dynarray_push(&layer->ids, id);
 850
 851         Action action = {
 852             .type = ACTION_NONE,
 853             .entity_id = {0}
 854         };
 855
 856         String action_string = trim(chop_word(&line));
 857         if (action_string.count > 0) {
 858             action.type = (ActionType)atol(string_to_cstr(memory, action_string));
 859             switch (action.type) {
 860             case ACTION_NONE: break;
 861             case ACTION_TOGGLE_GOAL:
 862             case ACTION_HIDE_LABEL: {
 863                 String label_id = trim(chop_word(&line));
 864                 trace_assert(label_id.count > 0);
 865                 memset(action.entity_id, 0, ENTITY_MAX_ID_SIZE);
 866                 memcpy(action.entity_id,
 867                        label_id.data,
 868                        min_size_t(
 869                            ENTITY_MAX_ID_SIZE - 1,
 870                            label_id.count));
 871             } break;
 872
 873             case ACTION_N: break;
 874             }
 875         }
 876
 877         dynarray_push(&layer->actions, &action);
 878     }
 879 }
 880
 881 int rect_layer_render(const RectLayer *layer, const Camera *camera, int active)
 882 {
 883     trace_assert(layer);
 884     trace_assert(camera);
 885
 886     const size_t n = layer->rects.count;
 887     Rect *rects = (Rect *)layer->rects.data;
 888     Color *colors = (Color *)layer->colors.data;
 889     const char *ids = (const char *)layer->ids.data;
 890
 891     // The Rectangles
 892     for (size_t i = 0; i < n; ++i) {
 893         Rect rect = rects[i];
 894         Color color = colors[i];
 895
 896         if (layer->selection == (int) i) {
 897             if (layer->state == RECT_LAYER_RESIZE || layer->state == RECT_LAYER_MOVE) {
 898                 rect = layer->inter_rect;
 899             }
 900
 901             if (layer->state == RECT_LAYER_RECOLOR) {
 902                 color = layer->inter_color;
 903             }
 904         }
 905
 906         // Main Rectangle
 907         if (camera_fill_rect(
 908                 camera,
 909                 rect,
 910                 color_scale(
 911                     color,
 912                     rgba(1.0f, 1.0f, 1.0f, active ? 1.0f : 0.5f))) < 0) {
 913             return -1;
 914         }
 915     }
 916
 917     // Selection Overlay
 918     if (active && layer->selection >= 0) {
 919         Rect rect = rects[layer->selection];
 920         Color color = colors[layer->selection];
 921
 922         if (layer->state == RECT_LAYER_RESIZE || layer->state == RECT_LAYER_MOVE) {
 923             rect = layer->inter_rect;
 924         }
 925
 926         if (layer->state == RECT_LAYER_RECOLOR) {
 927             color = layer->inter_color;
 928         }
 929
 930         const Rect overlay_rect =
 931             rect_pad(
 932                 camera_rect(camera, rect),
 933                 -RECT_LAYER_SELECTION_THICCNESS * 0.5f);
 934         const Color overlay_color = color_invert(color);
 935
 936         // Selection
 937         if (camera_draw_thicc_rect_screen(
 938                 camera,
 939                 overlay_rect,
 940                 overlay_color,
 941                 RECT_LAYER_SELECTION_THICCNESS) < 0) {
 942             return -1;
 943         }
 944
 945         const Vec2f rect_id_pos = vec_sub(
 946             rect_position(rect),
 947             vec_mult(
 948                 RECT_LAYER_ID_LABEL_SIZE,
 949                 vec(0.0f, FONT_CHAR_HEIGHT)));
 950
 951         // Rectangle Id
 952         if (layer->state == RECT_LAYER_ID_RENAME) {
 953             // ID renaming Edit Field
 954             if (edit_field_render_world(
 955                     &layer->id_edit_field,
 956                     camera,
 957                     rect_id_pos) < 0) {
 958                 return -1;
 959             }
 960         } else {
 961             // Id text
 962             if (camera_render_text(
 963                     camera,
 964                     ids + layer->selection * ENTITY_MAX_ID_SIZE,
 965                     RECT_LAYER_ID_LABEL_SIZE,
 966                     color_invert(color),
 967                     rect_id_pos) < 0) {
 968                 return -1;
 969             }
 970         }
 971     }
 972
 973     // Proto Rectangle
 974     const Color color = color_picker_rgba(&layer->color_picker);
 975     if (layer->state == RECT_LAYER_CREATE) {
 976         if (camera_fill_rect(camera, rect_from_points(layer->create_begin, layer->create_end), color) < 0) {
 977             return -1;
 978         }
 979     }
 980
 981     if (active && color_picker_render(&layer->color_picker, camera) < 0) {
 982         return -1;
 983     }
 984
 985     return 0;
 986 }
 987
 988 static
 989 int rect_layer_event_recolor(RectLayer *layer,
 990                              const SDL_Event *event,
 991                              const Camera *camera,
 992                              UndoHistory *undo_history)
 993 {
 994     trace_assert(layer);
 995     trace_assert(event);
 996     trace_assert(camera);
 997     trace_assert(undo_history);
 998     trace_assert(layer->selection >= 0);
 999
1000     int color_changed = 0;
1001     if (color_picker_event(&layer->color_picker, event, camera, &color_changed) < 0) {
1002         return -1;
1003     }
1004
1005     if (color_changed) {
1006         layer->inter_color = color_picker_rgba(&layer->color_picker);
1007
1008         if (!color_picker_drag(&layer->color_picker)) {
1009             RECT_UNDO_PUSH(undo_history, create_rect_undo_update_context(layer));
1010             dynarray_replace_at(&layer->colors, (size_t) layer->selection, &layer->inter_color);
1011             layer->state = RECT_LAYER_IDLE;
1012         }
1013     }
1014
1015     return 0;
1016 }
1017
1018 int rect_layer_event(RectLayer *layer,
1019                      const SDL_Event *event,
1020                      const Camera *camera,
1021                      UndoHistory *undo_history)
1022 {
1023     trace_assert(layer);
1024     trace_assert(event);
1025     trace_assert(undo_history);
1026
1027     switch (layer->state) {
1028     case RECT_LAYER_IDLE:
1029         return rect_layer_event_idle(layer, event, camera, undo_history);
1030
1031     case RECT_LAYER_CREATE:
1032         return rect_layer_event_create(layer, event, camera, undo_history);
1033
1034     case RECT_LAYER_RESIZE:
1035         return rect_layer_event_resize(layer, event, camera, undo_history);
1036
1037     case RECT_LAYER_MOVE:
1038         return rect_layer_event_move(layer, event, camera, undo_history);
1039
1040     case RECT_LAYER_ID_RENAME:
1041         return rect_layer_event_id_rename(layer, event, camera, undo_history);
1042
1043     case RECT_LAYER_RECOLOR:
1044         return rect_layer_event_recolor(layer, event, camera, undo_history);
1045     }
1046
1047
1048     return 0;
1049 }
1050
1051 size_t rect_layer_count(const RectLayer *layer)
1052 {
1053     return layer->rects.count;
1054 }
1055
1056 const Rect *rect_layer_rects(const RectLayer *layer)
1057 {
1058     return (const Rect *)layer->rects.data;
1059 }
1060
1061 const Color *rect_layer_colors(const RectLayer *layer)
1062 {
1063     return (const Color *)layer->colors.data;
1064 }
1065
1066 const char *rect_layer_ids(const RectLayer *layer)
1067 {
1068     return (const char *)layer->ids.data;
1069 }
1070
1071 int rect_layer_dump_stream(const RectLayer *layer, FILE *filedump)
1072 {
1073     trace_assert(layer);
1074     trace_assert(filedump);
1075
1076     size_t n = layer->ids.count;
1077     char *ids = (char *)layer->ids.data;
1078     Rect *rects = (Rect *)layer->rects.data;
1079     Color *colors = (Color *)layer->colors.data;
1080     Action *actions = (Action *)layer->actions.data;
1081
1082     fprintf(filedump, "%zd\n", n);
1083     for (size_t i = 0; i < n; ++i) {
1084         fprintf(filedump, "%s %f %f %f %f ",
1085                 ids + ENTITY_MAX_ID_SIZE * i,
1086                 rects[i].x, rects[i].y, rects[i].w, rects[i].h);
1087         color_hex_to_stream(colors[i], filedump);
1088
1089         switch (actions[i].type) {
1090         case ACTION_NONE: {} break;
1091
1092         case ACTION_TOGGLE_GOAL:
1093         case ACTION_HIDE_LABEL: {
1094             fprintf(filedump, " %d %.*s",
1095                     (int)actions[i].type,
1096                     ENTITY_MAX_ID_SIZE, actions[i].entity_id);
1097         } break;
1098         case ACTION_N: break;
1099         }
1100
1101         fprintf(filedump, "\n");
1102     }
1103
1104     return 0;
1105 }
1106
1107 const Action *rect_layer_actions(const RectLayer *layer)
1108 {
1109     return (const Action *)layer->actions.data;
1110 }