Files @ r28616:1df48a6fd940
Branch filter:

Location: cpp/openttd-patchpack/source/src/spritecache.cpp

glx22
Fix 48b6b18: Increase MAX_VALUATE_OPS to match the previous limit
   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
/*
 * This file is part of OpenTTD.
 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/** @file spritecache.cpp Caching of sprites. */

#include "stdafx.h"
#include "random_access_file_type.h"
#include "spriteloader/grf.hpp"
#include "gfx_func.h"
#include "error.h"
#include "error_func.h"
#include "zoom_func.h"
#include "settings_type.h"
#include "blitter/factory.hpp"
#include "core/math_func.hpp"
#include "core/mem_func.hpp"
#include "video/video_driver.hpp"
#include "spritecache.h"
#include "spritecache_internal.h"

#include "table/sprites.h"
#include "table/strings.h"
#include "table/palette_convert.h"

#include "safeguards.h"

/* Default of 4MB spritecache */
uint _sprite_cache_size = 4;


static uint _spritecache_items = 0;
static SpriteCache *_spritecache = nullptr;
static std::vector<std::unique_ptr<SpriteFile>> _sprite_files;

static inline SpriteCache *GetSpriteCache(uint index)
{
	return &_spritecache[index];
}

SpriteCache *AllocateSpriteCache(uint index)
{
	if (index >= _spritecache_items) {
		/* Add another 1024 items to the 'pool' */
		uint items = Align(index + 1, 1024);

		Debug(sprite, 4, "Increasing sprite cache to {} items ({} bytes)", items, items * sizeof(*_spritecache));

		_spritecache = ReallocT(_spritecache, items);

		/* Reset the new items and update the count */
		memset(_spritecache + _spritecache_items, 0, (items - _spritecache_items) * sizeof(*_spritecache));
		_spritecache_items = items;
	}

	return GetSpriteCache(index);
}

/**
 * Get the cached SpriteFile given the name of the file.
 * @param filename The name of the file at the disk.
 * @return The SpriteFile or \c null.
 */
static SpriteFile *GetCachedSpriteFileByName(const std::string &filename)
{
	for (auto &f : _sprite_files) {
		if (f->GetFilename() == filename) {
			return f.get();
		}
	}
	return nullptr;
}

/**
 * Open/get the SpriteFile that is cached for use in the sprite cache.
 * @param filename      Name of the file at the disk.
 * @param subdir        The sub directory to search this file in.
 * @param palette_remap Whether a palette remap needs to be performed for this file.
 * @return The reference to the SpriteCache.
 */
SpriteFile &OpenCachedSpriteFile(const std::string &filename, Subdirectory subdir, bool palette_remap)
{
	SpriteFile *file = GetCachedSpriteFileByName(filename);
	if (file == nullptr) {
		file = _sprite_files.insert(std::end(_sprite_files), std::make_unique<SpriteFile>(filename, subdir, palette_remap))->get();
	} else {
		file->SeekToBegin();
	}
	return *file;
}

struct MemBlock {
	size_t size;
	byte data[];
};

static uint _sprite_lru_counter;
static MemBlock *_spritecache_ptr;
static uint _allocated_sprite_cache_size = 0;
static int _compact_cache_counter;

static void CompactSpriteCache();

/**
 * Skip the given amount of sprite graphics data.
 * @param type the type of sprite (compressed etc)
 * @param num the amount of sprites to skip
 * @return true if the data could be correctly skipped.
 */
bool SkipSpriteData(SpriteFile &file, byte type, uint16_t num)
{
	if (type & 2) {
		file.SkipBytes(num);
	} else {
		while (num > 0) {
			int8_t i = file.ReadByte();
			if (i >= 0) {
				int size = (i == 0) ? 0x80 : i;
				if (size > num) return false;
				num -= size;
				file.SkipBytes(size);
			} else {
				i = -(i >> 3);
				num -= i;
				file.ReadByte();
			}
		}
	}
	return true;
}

/* Check if the given Sprite ID exists */
bool SpriteExists(SpriteID id)
{
	if (id >= _spritecache_items) return false;

	/* Special case for Sprite ID zero -- its position is also 0... */
	if (id == 0) return true;
	return !(GetSpriteCache(id)->file_pos == 0 && GetSpriteCache(id)->file == nullptr);
}

/**
 * Get the sprite type of a given sprite.
 * @param sprite The sprite to look at.
 * @return the type of sprite.
 */
SpriteType GetSpriteType(SpriteID sprite)
{
	if (!SpriteExists(sprite)) return SpriteType::Invalid;
	return GetSpriteCache(sprite)->type;
}

/**
 * Get the SpriteFile of a given sprite.
 * @param sprite The sprite to look at.
 * @return The SpriteFile.
 */
SpriteFile *GetOriginFile(SpriteID sprite)
{
	if (!SpriteExists(sprite)) return nullptr;
	return GetSpriteCache(sprite)->file;
}

/**
 * Get the GRF-local sprite id of a given sprite.
 * @param sprite The sprite to look at.
 * @return The GRF-local sprite id.
 */
uint32_t GetSpriteLocalID(SpriteID sprite)
{
	if (!SpriteExists(sprite)) return 0;
	return GetSpriteCache(sprite)->id;
}

/**
 * Count the sprites which originate from a specific file in a range of SpriteIDs.
 * @param file The loaded SpriteFile.
 * @param begin First sprite in range.
 * @param end First sprite not in range.
 * @return Number of sprites.
 */
uint GetSpriteCountForFile(const std::string &filename, SpriteID begin, SpriteID end)
{
	SpriteFile *file = GetCachedSpriteFileByName(filename);
	if (file == nullptr) return 0;

	uint count = 0;
	for (SpriteID i = begin; i != end; i++) {
		if (SpriteExists(i)) {
			SpriteCache *sc = GetSpriteCache(i);
			if (sc->file == file) {
				count++;
				Debug(sprite, 4, "Sprite: {}", i);
			}
		}
	}
	return count;
}

/**
 * Get a reasonable (upper bound) estimate of the maximum
 * SpriteID used in OpenTTD; there will be no sprites with
 * a higher SpriteID, although there might be up to roughly
 * a thousand unused SpriteIDs below this number.
 * @note It's actually the number of spritecache items.
 * @return maximum SpriteID
 */
uint GetMaxSpriteID()
{
	return _spritecache_items;
}

static bool ResizeSpriteIn(SpriteLoader::SpriteCollection &sprite, ZoomLevel src, ZoomLevel tgt)
{
	uint8_t scaled_1 = ScaleByZoom(1, (ZoomLevel)(src - tgt));

	/* Check for possible memory overflow. */
	if (sprite[src].width * scaled_1 > UINT16_MAX || sprite[src].height * scaled_1 > UINT16_MAX) return false;

	sprite[tgt].width  = sprite[src].width  * scaled_1;
	sprite[tgt].height = sprite[src].height * scaled_1;
	sprite[tgt].x_offs = sprite[src].x_offs * scaled_1;
	sprite[tgt].y_offs = sprite[src].y_offs * scaled_1;
	sprite[tgt].colours = sprite[src].colours;

	sprite[tgt].AllocateData(tgt, static_cast<size_t>(sprite[tgt].width) * sprite[tgt].height);

	SpriteLoader::CommonPixel *dst = sprite[tgt].data;
	for (int y = 0; y < sprite[tgt].height; y++) {
		const SpriteLoader::CommonPixel *src_ln = &sprite[src].data[y / scaled_1 * sprite[src].width];
		for (int x = 0; x < sprite[tgt].width; x++) {
			*dst = src_ln[x / scaled_1];
			dst++;
		}
	}

	return true;
}

static void ResizeSpriteOut(SpriteLoader::SpriteCollection &sprite, ZoomLevel zoom)
{
	/* Algorithm based on 32bpp_Optimized::ResizeSprite() */
	sprite[zoom].width  = UnScaleByZoom(sprite[ZOOM_LVL_NORMAL].width,  zoom);
	sprite[zoom].height = UnScaleByZoom(sprite[ZOOM_LVL_NORMAL].height, zoom);
	sprite[zoom].x_offs = UnScaleByZoom(sprite[ZOOM_LVL_NORMAL].x_offs, zoom);
	sprite[zoom].y_offs = UnScaleByZoom(sprite[ZOOM_LVL_NORMAL].y_offs, zoom);
	sprite[zoom].colours = sprite[ZOOM_LVL_NORMAL].colours;

	sprite[zoom].AllocateData(zoom, static_cast<size_t>(sprite[zoom].height) * sprite[zoom].width);

	SpriteLoader::CommonPixel *dst = sprite[zoom].data;
	const SpriteLoader::CommonPixel *src = sprite[zoom - 1].data;
	[[maybe_unused]] const SpriteLoader::CommonPixel *src_end = src + sprite[zoom - 1].height * sprite[zoom - 1].width;

	for (uint y = 0; y < sprite[zoom].height; y++) {
		const SpriteLoader::CommonPixel *src_ln = src + sprite[zoom - 1].width;
		assert(src_ln <= src_end);
		for (uint x = 0; x < sprite[zoom].width; x++) {
			assert(src < src_ln);
			if (src + 1 != src_ln && (src + 1)->a != 0) {
				*dst = *(src + 1);
			} else {
				*dst = *src;
			}
			dst++;
			src += 2;
		}
		src = src_ln + sprite[zoom - 1].width;
	}
}

static bool PadSingleSprite(SpriteLoader::Sprite *sprite, ZoomLevel zoom, uint pad_left, uint pad_top, uint pad_right, uint pad_bottom)
{
	uint width  = sprite->width + pad_left + pad_right;
	uint height = sprite->height + pad_top + pad_bottom;

	if (width > UINT16_MAX || height > UINT16_MAX) return false;

	/* Copy source data and reallocate sprite memory. */
	size_t sprite_size = static_cast<size_t>(sprite->width) * sprite->height;
	SpriteLoader::CommonPixel *src_data = MallocT<SpriteLoader::CommonPixel>(sprite_size);
	MemCpyT(src_data, sprite->data, sprite_size);
	sprite->AllocateData(zoom, static_cast<size_t>(width) * height);

	/* Copy with padding to destination. */
	SpriteLoader::CommonPixel *src = src_data;
	SpriteLoader::CommonPixel *data = sprite->data;
	for (uint y = 0; y < height; y++) {
		if (y < pad_top || pad_bottom + y >= height) {
			/* Top/bottom padding. */
			MemSetT(data, 0, width);
			data += width;
		} else {
			if (pad_left > 0) {
				/* Pad left. */
				MemSetT(data, 0, pad_left);
				data += pad_left;
			}

			/* Copy pixels. */
			MemCpyT(data, src, sprite->width);
			src += sprite->width;
			data += sprite->width;

			if (pad_right > 0) {
				/* Pad right. */
				MemSetT(data, 0, pad_right);
				data += pad_right;
			}
		}
	}
	free(src_data);

	/* Update sprite size. */
	sprite->width   = width;
	sprite->height  = height;
	sprite->x_offs -= pad_left;
	sprite->y_offs -= pad_top;

	return true;
}

static bool PadSprites(SpriteLoader::SpriteCollection &sprite, uint8_t sprite_avail, SpriteEncoder *encoder)
{
	/* Get minimum top left corner coordinates. */
	int min_xoffs = INT32_MAX;
	int min_yoffs = INT32_MAX;
	for (ZoomLevel zoom = ZOOM_LVL_BEGIN; zoom != ZOOM_LVL_END; zoom++) {
		if (HasBit(sprite_avail, zoom)) {
			min_xoffs = std::min(min_xoffs, ScaleByZoom(sprite[zoom].x_offs, zoom));
			min_yoffs = std::min(min_yoffs, ScaleByZoom(sprite[zoom].y_offs, zoom));
		}
	}

	/* Get maximum dimensions taking necessary padding at the top left into account. */
	int max_width  = INT32_MIN;
	int max_height = INT32_MIN;
	for (ZoomLevel zoom = ZOOM_LVL_BEGIN; zoom != ZOOM_LVL_END; zoom++) {
		if (HasBit(sprite_avail, zoom)) {
			max_width  = std::max(max_width, ScaleByZoom(sprite[zoom].width + sprite[zoom].x_offs - UnScaleByZoom(min_xoffs, zoom), zoom));
			max_height = std::max(max_height, ScaleByZoom(sprite[zoom].height + sprite[zoom].y_offs - UnScaleByZoom(min_yoffs, zoom), zoom));
		}
	}

	/* Align height and width if required to match the needs of the sprite encoder. */
	uint align = encoder->GetSpriteAlignment();
	if (align != 0) {
		max_width  = Align(max_width,  align);
		max_height = Align(max_height, align);
	}

	/* Pad sprites where needed. */
	for (ZoomLevel zoom = ZOOM_LVL_BEGIN; zoom != ZOOM_LVL_END; zoom++) {
		if (HasBit(sprite_avail, zoom)) {
			/* Scaling the sprite dimensions in the blitter is done with rounding up,
			 * so a negative padding here is not an error. */
			int pad_left   = std::max(0, sprite[zoom].x_offs - UnScaleByZoom(min_xoffs, zoom));
			int pad_top    = std::max(0, sprite[zoom].y_offs - UnScaleByZoom(min_yoffs, zoom));
			int pad_right  = std::max(0, UnScaleByZoom(max_width, zoom) - sprite[zoom].width - pad_left);
			int pad_bottom = std::max(0, UnScaleByZoom(max_height, zoom) - sprite[zoom].height - pad_top);

			if (pad_left > 0 || pad_right > 0 || pad_top > 0 || pad_bottom > 0) {
				if (!PadSingleSprite(&sprite[zoom], zoom, pad_left, pad_top, pad_right, pad_bottom)) return false;
			}
		}
	}

	return true;
}

static bool ResizeSprites(SpriteLoader::SpriteCollection &sprite, uint8_t sprite_avail, SpriteEncoder *encoder)
{
	/* Create a fully zoomed image if it does not exist */
	ZoomLevel first_avail = static_cast<ZoomLevel>(FindFirstBit(sprite_avail));
	if (first_avail != ZOOM_LVL_NORMAL) {
		if (!ResizeSpriteIn(sprite, first_avail, ZOOM_LVL_NORMAL)) return false;
		SetBit(sprite_avail, ZOOM_LVL_NORMAL);
	}

	/* Pad sprites to make sizes match. */
	if (!PadSprites(sprite, sprite_avail, encoder)) return false;

	/* Create other missing zoom levels */
	for (ZoomLevel zoom = ZOOM_LVL_OUT_2X; zoom != ZOOM_LVL_END; zoom++) {
		if (HasBit(sprite_avail, zoom)) {
			/* Check that size and offsets match the fully zoomed image. */
			assert(sprite[zoom].width  == UnScaleByZoom(sprite[ZOOM_LVL_NORMAL].width,  zoom));
			assert(sprite[zoom].height == UnScaleByZoom(sprite[ZOOM_LVL_NORMAL].height, zoom));
			assert(sprite[zoom].x_offs == UnScaleByZoom(sprite[ZOOM_LVL_NORMAL].x_offs, zoom));
			assert(sprite[zoom].y_offs == UnScaleByZoom(sprite[ZOOM_LVL_NORMAL].y_offs, zoom));
		}

		/* Zoom level is not available, or unusable, so create it */
		if (!HasBit(sprite_avail, zoom)) ResizeSpriteOut(sprite, zoom);
	}

	/* Upscale to desired sprite_min_zoom if provided sprite only had zoomed in versions. */
	if (first_avail < _settings_client.gui.sprite_zoom_min) {
		if (_settings_client.gui.sprite_zoom_min >= ZOOM_LVL_OUT_4X) ResizeSpriteIn(sprite, ZOOM_LVL_OUT_4X, ZOOM_LVL_OUT_2X);
		if (_settings_client.gui.sprite_zoom_min >= ZOOM_LVL_OUT_2X) ResizeSpriteIn(sprite, ZOOM_LVL_OUT_2X, ZOOM_LVL_NORMAL);
	}

	return  true;
}

/**
 * Load a recolour sprite into memory.
 * @param file GRF we're reading from.
 * @param num Size of the sprite in the GRF.
 * @return Sprite data.
 */
static void *ReadRecolourSprite(SpriteFile &file, uint num)
{
	/* "Normal" recolour sprites are ALWAYS 257 bytes. Then there is a small
	 * number of recolour sprites that are 17 bytes that only exist in DOS
	 * GRFs which are the same as 257 byte recolour sprites, but with the last
	 * 240 bytes zeroed.  */
	static const uint RECOLOUR_SPRITE_SIZE = 257;
	byte *dest = (byte *)AllocSprite(std::max(RECOLOUR_SPRITE_SIZE, num));

	if (file.NeedsPaletteRemap()) {
		byte *dest_tmp = new byte[std::max(RECOLOUR_SPRITE_SIZE, num)];

		/* Only a few recolour sprites are less than 257 bytes */
		if (num < RECOLOUR_SPRITE_SIZE) memset(dest_tmp, 0, RECOLOUR_SPRITE_SIZE);
		file.ReadBlock(dest_tmp, num);

		/* The data of index 0 is never used; "literal 00" according to the (New)GRF specs. */
		for (uint i = 1; i < RECOLOUR_SPRITE_SIZE; i++) {
			dest[i] = _palmap_w2d[dest_tmp[_palmap_d2w[i - 1] + 1]];
		}
		delete[] dest_tmp;
	} else {
		file.ReadBlock(dest, num);
	}

	return dest;
}

/**
 * Read a sprite from disk.
 * @param sc          Location of sprite.
 * @param id          Sprite number.
 * @param sprite_type Type of sprite.
 * @param allocator   Allocator function to use.
 * @param encoder     Sprite encoder to use.
 * @return Read sprite data.
 */
static void *ReadSprite(const SpriteCache *sc, SpriteID id, SpriteType sprite_type, AllocatorProc *allocator, SpriteEncoder *encoder)
{
	/* Use current blitter if no other sprite encoder is given. */
	if (encoder == nullptr) encoder = BlitterFactory::GetCurrentBlitter();

	SpriteFile &file = *sc->file;
	size_t file_pos = sc->file_pos;

	assert(sprite_type != SpriteType::Recolour);
	assert(IsMapgenSpriteID(id) == (sprite_type == SpriteType::MapGen));
	assert(sc->type == sprite_type);

	Debug(sprite, 9, "Load sprite {}", id);

	SpriteLoader::SpriteCollection sprite;
	uint8_t sprite_avail = 0;
	sprite[ZOOM_LVL_NORMAL].type = sprite_type;

	SpriteLoaderGrf sprite_loader(file.GetContainerVersion());
	if (sprite_type != SpriteType::MapGen && encoder->Is32BppSupported()) {
		/* Try for 32bpp sprites first. */
		sprite_avail = sprite_loader.LoadSprite(sprite, file, file_pos, sprite_type, true, sc->control_flags);
	}
	if (sprite_avail == 0) {
		sprite_avail = sprite_loader.LoadSprite(sprite, file, file_pos, sprite_type, false, sc->control_flags);
	}

	if (sprite_avail == 0) {
		if (sprite_type == SpriteType::MapGen) return nullptr;
		if (id == SPR_IMG_QUERY) UserError("Okay... something went horribly wrong. I couldn't load the fallback sprite. What should I do?");
		return (void*)GetRawSprite(SPR_IMG_QUERY, SpriteType::Normal, allocator, encoder);
	}

	if (sprite_type == SpriteType::MapGen) {
		/* Ugly hack to work around the problem that the old landscape
		 *  generator assumes that those sprites are stored uncompressed in
		 *  the memory, and they are only read directly by the code, never
		 *  send to the blitter. So do not send it to the blitter (which will
		 *  result in a data array in the format the blitter likes most), but
		 *  extract the data directly and store that as sprite.
		 * Ugly: yes. Other solution: no. Blame the original author or
		 *  something ;) The image should really have been a data-stream
		 *  (so type = 0xFF basically). */
		uint num = sprite[ZOOM_LVL_NORMAL].width * sprite[ZOOM_LVL_NORMAL].height;

		Sprite *s = (Sprite *)allocator(sizeof(*s) + num);
		s->width  = sprite[ZOOM_LVL_NORMAL].width;
		s->height = sprite[ZOOM_LVL_NORMAL].height;
		s->x_offs = sprite[ZOOM_LVL_NORMAL].x_offs;
		s->y_offs = sprite[ZOOM_LVL_NORMAL].y_offs;

		SpriteLoader::CommonPixel *src = sprite[ZOOM_LVL_NORMAL].data;
		byte *dest = s->data;
		while (num-- > 0) {
			*dest++ = src->m;
			src++;
		}

		return s;
	}

	if (!ResizeSprites(sprite, sprite_avail, encoder)) {
		if (id == SPR_IMG_QUERY) UserError("Okay... something went horribly wrong. I couldn't resize the fallback sprite. What should I do?");
		return (void*)GetRawSprite(SPR_IMG_QUERY, SpriteType::Normal, allocator, encoder);
	}

	if (sprite[ZOOM_LVL_NORMAL].type == SpriteType::Font && _font_zoom != ZOOM_LVL_NORMAL) {
		/* Make ZOOM_LVL_NORMAL be ZOOM_LVL_GUI */
		sprite[ZOOM_LVL_NORMAL].width  = sprite[_font_zoom].width;
		sprite[ZOOM_LVL_NORMAL].height = sprite[_font_zoom].height;
		sprite[ZOOM_LVL_NORMAL].x_offs = sprite[_font_zoom].x_offs;
		sprite[ZOOM_LVL_NORMAL].y_offs = sprite[_font_zoom].y_offs;
		sprite[ZOOM_LVL_NORMAL].data   = sprite[_font_zoom].data;
		sprite[ZOOM_LVL_NORMAL].colours = sprite[_font_zoom].colours;
	}

	return encoder->Encode(sprite, allocator);
}

struct GrfSpriteOffset {
	size_t file_pos;
	byte control_flags;
};

/** Map from sprite numbers to position in the GRF file. */
static std::map<uint32_t, GrfSpriteOffset> _grf_sprite_offsets;

/**
 * Get the file offset for a specific sprite in the sprite section of a GRF.
 * @param id ID of the sprite to look up.
 * @return Position of the sprite in the sprite section or SIZE_MAX if no such sprite is present.
 */
size_t GetGRFSpriteOffset(uint32_t id)
{
	return _grf_sprite_offsets.find(id) != _grf_sprite_offsets.end() ? _grf_sprite_offsets[id].file_pos : SIZE_MAX;
}

/**
 * Parse the sprite section of GRFs.
 * @param container_version Container version of the GRF we're currently processing.
 */
void ReadGRFSpriteOffsets(SpriteFile &file)
{
	_grf_sprite_offsets.clear();

	if (file.GetContainerVersion() >= 2) {
		/* Seek to sprite section of the GRF. */
		size_t data_offset = file.ReadDword();
		size_t old_pos = file.GetPos();
		file.SeekTo(data_offset, SEEK_CUR);

		GrfSpriteOffset offset = { 0, 0 };

		/* Loop over all sprite section entries and store the file
		 * offset for each newly encountered ID. */
		uint32_t id, prev_id = 0;
		while ((id = file.ReadDword()) != 0) {
			if (id != prev_id) {
				_grf_sprite_offsets[prev_id] = offset;
				offset.file_pos = file.GetPos() - 4;
				offset.control_flags = 0;
			}
			prev_id = id;
			uint length = file.ReadDword();
			if (length > 0) {
				byte colour = file.ReadByte() & SCC_MASK;
				length--;
				if (length > 0) {
					byte zoom = file.ReadByte();
					length--;
					if (colour != 0 && zoom == 0) { // ZOOM_LVL_OUT_4X (normal zoom)
						SetBit(offset.control_flags, (colour != SCC_PAL) ? SCCF_ALLOW_ZOOM_MIN_1X_32BPP : SCCF_ALLOW_ZOOM_MIN_1X_PAL);
						SetBit(offset.control_flags, (colour != SCC_PAL) ? SCCF_ALLOW_ZOOM_MIN_2X_32BPP : SCCF_ALLOW_ZOOM_MIN_2X_PAL);
					}
					if (colour != 0 && zoom == 2) { // ZOOM_LVL_OUT_2X (2x zoomed in)
						SetBit(offset.control_flags, (colour != SCC_PAL) ? SCCF_ALLOW_ZOOM_MIN_2X_32BPP : SCCF_ALLOW_ZOOM_MIN_2X_PAL);
					}
				}
			}
			file.SkipBytes(length);
		}
		if (prev_id != 0) _grf_sprite_offsets[prev_id] = offset;

		/* Continue processing the data section. */
		file.SeekTo(old_pos, SEEK_SET);
	}
}


/**
 * Load a real or recolour sprite.
 * @param load_index Global sprite index.
 * @param file GRF to load from.
 * @param file_sprite_id Sprite number in the GRF.
 * @param container_version Container version of the GRF.
 * @return True if a valid sprite was loaded, false on any error.
 */
bool LoadNextSprite(int load_index, SpriteFile &file, uint file_sprite_id)
{
	size_t file_pos = file.GetPos();

	/* Read sprite header. */
	uint32_t num = file.GetContainerVersion() >= 2 ? file.ReadDword() : file.ReadWord();
	if (num == 0) return false;
	byte grf_type = file.ReadByte();

	SpriteType type;
	void *data = nullptr;
	byte control_flags = 0;
	if (grf_type == 0xFF) {
		/* Some NewGRF files have "empty" pseudo-sprites which are 1
		 * byte long. Catch these so the sprites won't be displayed. */
		if (num == 1) {
			file.ReadByte();
			return false;
		}
		type = SpriteType::Recolour;
		data = ReadRecolourSprite(file, num);
	} else if (file.GetContainerVersion() >= 2 && grf_type == 0xFD) {
		if (num != 4) {
			/* Invalid sprite section include, ignore. */
			file.SkipBytes(num);
			return false;
		}
		/* It is not an error if no sprite with the provided ID is found in the sprite section. */
		auto iter = _grf_sprite_offsets.find(file.ReadDword());
		if (iter != _grf_sprite_offsets.end()) {
			file_pos = iter->second.file_pos;
			control_flags = iter->second.control_flags;
		} else {
			file_pos = SIZE_MAX;
		}
		type = SpriteType::Normal;
	} else {
		file.SkipBytes(7);
		type = SkipSpriteData(file, grf_type, num - 8) ? SpriteType::Normal : SpriteType::Invalid;
		/* Inline sprites are not supported for container version >= 2. */
		if (file.GetContainerVersion() >= 2) return false;
	}

	if (type == SpriteType::Invalid) return false;

	if (load_index >= MAX_SPRITES) {
		UserError("Tried to load too many sprites (#{}; max {})", load_index, MAX_SPRITES);
	}

	bool is_mapgen = IsMapgenSpriteID(load_index);

	if (is_mapgen) {
		if (type != SpriteType::Normal) UserError("Uhm, would you be so kind not to load a NewGRF that changes the type of the map generator sprites?");
		type = SpriteType::MapGen;
	}

	SpriteCache *sc = AllocateSpriteCache(load_index);
	sc->file = &file;
	sc->file_pos = file_pos;
	sc->ptr = data;
	sc->lru = 0;
	sc->id = file_sprite_id;
	sc->type = type;
	sc->warned = false;
	sc->control_flags = control_flags;

	return true;
}


void DupSprite(SpriteID old_spr, SpriteID new_spr)
{
	SpriteCache *scnew = AllocateSpriteCache(new_spr); // may reallocate: so put it first
	SpriteCache *scold = GetSpriteCache(old_spr);

	scnew->file = scold->file;
	scnew->file_pos = scold->file_pos;
	scnew->ptr = nullptr;
	scnew->id = scold->id;
	scnew->type = scold->type;
	scnew->warned = false;
}

/**
 * S_FREE_MASK is used to mask-out lower bits of MemBlock::size
 * If they are non-zero, the block is free.
 * S_FREE_MASK has to ensure MemBlock is correctly aligned -
 * it means 8B (S_FREE_MASK == 7) on 64bit systems!
 */
static const size_t S_FREE_MASK = sizeof(size_t) - 1;

/* to make sure nobody adds things to MemBlock without checking S_FREE_MASK first */
static_assert(sizeof(MemBlock) == sizeof(size_t));
/* make sure it's a power of two */
static_assert((sizeof(size_t) & (sizeof(size_t) - 1)) == 0);

static inline MemBlock *NextBlock(MemBlock *block)
{
	return (MemBlock*)((byte*)block + (block->size & ~S_FREE_MASK));
}

static size_t GetSpriteCacheUsage()
{
	size_t tot_size = 0;
	MemBlock *s;

	for (s = _spritecache_ptr; s->size != 0; s = NextBlock(s)) {
		if (!(s->size & S_FREE_MASK)) tot_size += s->size;
	}

	return tot_size;
}


void IncreaseSpriteLRU()
{
	/* Increase all LRU values */
	if (_sprite_lru_counter > 16384) {
		SpriteID i;

		Debug(sprite, 5, "Fixing lru {}, inuse={}", _sprite_lru_counter, GetSpriteCacheUsage());

		for (i = 0; i != _spritecache_items; i++) {
			SpriteCache *sc = GetSpriteCache(i);
			if (sc->ptr != nullptr) {
				if (sc->lru >= 0) {
					sc->lru = -1;
				} else if (sc->lru != -32768) {
					sc->lru--;
				}
			}
		}
		_sprite_lru_counter = 0;
	}

	/* Compact sprite cache every now and then. */
	if (++_compact_cache_counter >= 740) {
		CompactSpriteCache();
		_compact_cache_counter = 0;
	}
}

/**
 * Called when holes in the sprite cache should be removed.
 * That is accomplished by moving the cached data.
 */
static void CompactSpriteCache()
{
	MemBlock *s;

	Debug(sprite, 3, "Compacting sprite cache, inuse={}", GetSpriteCacheUsage());

	for (s = _spritecache_ptr; s->size != 0;) {
		if (s->size & S_FREE_MASK) {
			MemBlock *next = NextBlock(s);
			MemBlock temp;
			SpriteID i;

			/* Since free blocks are automatically coalesced, this should hold true. */
			assert(!(next->size & S_FREE_MASK));

			/* If the next block is the sentinel block, we can safely return */
			if (next->size == 0) break;

			/* Locate the sprite belonging to the next pointer. */
			for (i = 0; GetSpriteCache(i)->ptr != next->data; i++) {
				assert(i != _spritecache_items);
			}

			GetSpriteCache(i)->ptr = s->data; // Adjust sprite array entry
			/* Swap this and the next block */
			temp = *s;
			memmove(s, next, next->size);
			s = NextBlock(s);
			*s = temp;

			/* Coalesce free blocks */
			while (NextBlock(s)->size & S_FREE_MASK) {
				s->size += NextBlock(s)->size & ~S_FREE_MASK;
			}
		} else {
			s = NextBlock(s);
		}
	}
}

/**
 * Delete a single entry from the sprite cache.
 * @param item Entry to delete.
 */
static void DeleteEntryFromSpriteCache(uint item)
{
	/* Mark the block as free (the block must be in use) */
	MemBlock *s = (MemBlock*)GetSpriteCache(item)->ptr - 1;
	assert(!(s->size & S_FREE_MASK));
	s->size |= S_FREE_MASK;
	GetSpriteCache(item)->ptr = nullptr;

	/* And coalesce adjacent free blocks */
	for (s = _spritecache_ptr; s->size != 0; s = NextBlock(s)) {
		if (s->size & S_FREE_MASK) {
			while (NextBlock(s)->size & S_FREE_MASK) {
				s->size += NextBlock(s)->size & ~S_FREE_MASK;
			}
		}
	}
}

static void DeleteEntryFromSpriteCache()
{
	uint best = UINT_MAX;
	int cur_lru;

	Debug(sprite, 3, "DeleteEntryFromSpriteCache, inuse={}", GetSpriteCacheUsage());

	cur_lru = 0xffff;
	for (SpriteID i = 0; i != _spritecache_items; i++) {
		SpriteCache *sc = GetSpriteCache(i);
		if (sc->type != SpriteType::Recolour && sc->ptr != nullptr && sc->lru < cur_lru) {
			cur_lru = sc->lru;
			best = i;
		}
	}

	/* Display an error message and die, in case we found no sprite at all.
	 * This shouldn't really happen, unless all sprites are locked. */
	if (best == UINT_MAX) FatalError("Out of sprite memory");

	DeleteEntryFromSpriteCache(best);
}

void *AllocSprite(size_t mem_req)
{
	mem_req += sizeof(MemBlock);

	/* Align this to correct boundary. This also makes sure at least one
	 * bit is not used, so we can use it for other things. */
	mem_req = Align(mem_req, S_FREE_MASK + 1);

	for (;;) {
		MemBlock *s;

		for (s = _spritecache_ptr; s->size != 0; s = NextBlock(s)) {
			if (s->size & S_FREE_MASK) {
				size_t cur_size = s->size & ~S_FREE_MASK;

				/* Is the block exactly the size we need or
				 * big enough for an additional free block? */
				if (cur_size == mem_req ||
						cur_size >= mem_req + sizeof(MemBlock)) {
					/* Set size and in use */
					s->size = mem_req;

					/* Do we need to inject a free block too? */
					if (cur_size != mem_req) {
						NextBlock(s)->size = (cur_size - mem_req) | S_FREE_MASK;
					}

					return s->data;
				}
			}
		}

		/* Reached sentinel, but no block found yet. Delete some old entry. */
		DeleteEntryFromSpriteCache();
	}
}

/**
 * Sprite allocator simply using malloc.
 */
void *SimpleSpriteAlloc(size_t size)
{
	return MallocT<byte>(size);
}

/**
 * Handles the case when a sprite of different type is requested than is present in the SpriteCache.
 * For SpriteType::Font sprites, it is normal. In other cases, default sprite is loaded instead.
 * @param sprite ID of loaded sprite
 * @param requested requested sprite type
 * @param sc the currently known sprite cache for the requested sprite
 * @return fallback sprite
 * @note this function will do UserError() in the case the fallback sprite isn't available
 */
static void *HandleInvalidSpriteRequest(SpriteID sprite, SpriteType requested, SpriteCache *sc, AllocatorProc *allocator)
{
	static const char * const sprite_types[] = {
		"normal",        // SpriteType::Normal
		"map generator", // SpriteType::MapGen
		"character",     // SpriteType::Font
		"recolour",      // SpriteType::Recolour
	};

	SpriteType available = sc->type;
	if (requested == SpriteType::Font && available == SpriteType::Normal) {
		if (sc->ptr == nullptr) sc->type = SpriteType::Font;
		return GetRawSprite(sprite, sc->type, allocator);
	}

	byte warning_level = sc->warned ? 6 : 0;
	sc->warned = true;
	Debug(sprite, warning_level, "Tried to load {} sprite #{} as a {} sprite. Probable cause: NewGRF interference", sprite_types[static_cast<byte>(available)], sprite, sprite_types[static_cast<byte>(requested)]);

	switch (requested) {
		case SpriteType::Normal:
			if (sprite == SPR_IMG_QUERY) UserError("Uhm, would you be so kind not to load a NewGRF that makes the 'query' sprite a non-normal sprite?");
			FALLTHROUGH;
		case SpriteType::Font:
			return GetRawSprite(SPR_IMG_QUERY, SpriteType::Normal, allocator);
		case SpriteType::Recolour:
			if (sprite == PALETTE_TO_DARK_BLUE) UserError("Uhm, would you be so kind not to load a NewGRF that makes the 'PALETTE_TO_DARK_BLUE' sprite a non-remap sprite?");
			return GetRawSprite(PALETTE_TO_DARK_BLUE, SpriteType::Recolour, allocator);
		case SpriteType::MapGen:
			/* this shouldn't happen, overriding of SpriteType::MapGen sprites is checked in LoadNextSprite()
			 * (the only case the check fails is when these sprites weren't even loaded...) */
		default:
			NOT_REACHED();
	}
}

/**
 * Reads a sprite (from disk or sprite cache).
 * If the sprite is not available or of wrong type, a fallback sprite is returned.
 * @param sprite Sprite to read.
 * @param type Expected sprite type.
 * @param allocator Allocator function to use. Set to nullptr to use the usual sprite cache.
 * @param encoder Sprite encoder to use. Set to nullptr to use the currently active blitter.
 * @return Sprite raw data
 */
void *GetRawSprite(SpriteID sprite, SpriteType type, AllocatorProc *allocator, SpriteEncoder *encoder)
{
	assert(type != SpriteType::MapGen || IsMapgenSpriteID(sprite));
	assert(type < SpriteType::Invalid);

	if (!SpriteExists(sprite)) {
		Debug(sprite, 1, "Tried to load non-existing sprite #{}. Probable cause: Wrong/missing NewGRFs", sprite);

		/* SPR_IMG_QUERY is a BIG FAT RED ? */
		sprite = SPR_IMG_QUERY;
	}

	SpriteCache *sc = GetSpriteCache(sprite);

	if (sc->type != type) return HandleInvalidSpriteRequest(sprite, type, sc, allocator);

	if (allocator == nullptr && encoder == nullptr) {
		/* Load sprite into/from spritecache */

		/* Update LRU */
		sc->lru = ++_sprite_lru_counter;

		/* Load the sprite, if it is not loaded, yet */
		if (sc->ptr == nullptr) sc->ptr = ReadSprite(sc, sprite, type, AllocSprite, nullptr);

		return sc->ptr;
	} else {
		/* Do not use the spritecache, but a different allocator. */
		return ReadSprite(sc, sprite, type, allocator, encoder);
	}
}


static void GfxInitSpriteCache()
{
	/* initialize sprite cache heap */
	int bpp = BlitterFactory::GetCurrentBlitter()->GetScreenDepth();
	uint target_size = (bpp > 0 ? _sprite_cache_size * bpp / 8 : 1) * 1024 * 1024;

	/* Remember 'target_size' from the previous allocation attempt, so we do not try to reach the target_size multiple times in case of failure. */
	static uint last_alloc_attempt = 0;

	if (_spritecache_ptr == nullptr || (_allocated_sprite_cache_size != target_size && target_size != last_alloc_attempt)) {
		delete[] reinterpret_cast<byte *>(_spritecache_ptr);

		last_alloc_attempt = target_size;
		_allocated_sprite_cache_size = target_size;

		do {
			/* Try to allocate 50% more to make sure we do not allocate almost all available. */
			_spritecache_ptr = reinterpret_cast<MemBlock *>(new(std::nothrow) byte[_allocated_sprite_cache_size + _allocated_sprite_cache_size / 2]);

			if (_spritecache_ptr != nullptr) {
				/* Allocation succeeded, but we wanted less. */
				delete[] reinterpret_cast<byte *>(_spritecache_ptr);
				_spritecache_ptr = reinterpret_cast<MemBlock *>(new byte[_allocated_sprite_cache_size]);
			} else if (_allocated_sprite_cache_size < 2 * 1024 * 1024) {
				UserError("Cannot allocate spritecache");
			} else {
				/* Try again to allocate half. */
				_allocated_sprite_cache_size >>= 1;
			}
		} while (_spritecache_ptr == nullptr);

		if (_allocated_sprite_cache_size != target_size) {
			Debug(misc, 0, "Not enough memory to allocate {} MiB of spritecache. Spritecache was reduced to {} MiB.", target_size / 1024 / 1024, _allocated_sprite_cache_size / 1024 / 1024);

			ErrorMessageData msg(STR_CONFIG_ERROR_OUT_OF_MEMORY, STR_CONFIG_ERROR_SPRITECACHE_TOO_BIG);
			msg.SetDParam(0, target_size);
			msg.SetDParam(1, _allocated_sprite_cache_size);
			ScheduleErrorMessage(msg);
		}
	}

	/* A big free block */
	_spritecache_ptr->size = (_allocated_sprite_cache_size - sizeof(MemBlock)) | S_FREE_MASK;
	/* Sentinel block (identified by size == 0) */
	NextBlock(_spritecache_ptr)->size = 0;
}

void GfxInitSpriteMem()
{
	GfxInitSpriteCache();

	/* Reset the spritecache 'pool' */
	free(_spritecache);
	_spritecache_items = 0;
	_spritecache = nullptr;

	_compact_cache_counter = 0;
	_sprite_files.clear();
}

/**
 * Remove all encoded sprites from the sprite cache without
 * discarding sprite location information.
 */
void GfxClearSpriteCache()
{
	/* Clear sprite ptr for all cached items */
	for (uint i = 0; i != _spritecache_items; i++) {
		SpriteCache *sc = GetSpriteCache(i);
		if (sc->type != SpriteType::Recolour && sc->ptr != nullptr) DeleteEntryFromSpriteCache(i);
	}

	VideoDriver::GetInstance()->ClearSystemSprites();
}

/**
 * Remove all encoded font sprites from the sprite cache without
 * discarding sprite location information.
 */
void GfxClearFontSpriteCache()
{
	/* Clear sprite ptr for all cached font items */
	for (uint i = 0; i != _spritecache_items; i++) {
		SpriteCache *sc = GetSpriteCache(i);
		if (sc->type == SpriteType::Font && sc->ptr != nullptr) DeleteEntryFromSpriteCache(i);
	}
}

/* static */ ReusableBuffer<SpriteLoader::CommonPixel> SpriteLoader::Sprite::buffer[ZOOM_LVL_END];