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
use num_traits::{Bounded, Num, NumCast}; use std::cmp::{max, min}; use std::fmt; /// Trait used by the [StaticAABB2DIndex] that is required to be implemented for type T. /// It is blanket implemented for all primitive numeric types. pub trait IndexableNum: Copy + Num + PartialOrd + Default + Bounded + NumCast { /// Simple default min implementation for [PartialOrd] types. #[inline(always)] fn min(self, other: Self) -> Self { if self < other { return self; } other } /// Simple default max implementation for [PartialOrd] types. #[inline(always)] fn max(self, other: Self) -> Self { if self > other { return self; } other } } // Blanket impl for all types satisfying the required trait bounds impl<T> IndexableNum for T where T: Copy + Num + PartialOrd + Default + Bounded + NumCast {} /// Error type for errors that may be returned in attempting to build the index. #[derive(Debug, PartialEq)] pub enum StaticAABB2DIndexBuildError { /// Error for the case when the number of items added does not match the size given at construction. ItemCountError { /// The number of items that were added. added: usize, /// The number of items that were expected (set at construction). expected: usize, }, /// Error for the case when the numeric type T used for the index fails to cast to/from u16. NumericCastError, } impl std::error::Error for StaticAABB2DIndexBuildError {} impl fmt::Display for StaticAABB2DIndexBuildError { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { match self { StaticAABB2DIndexBuildError::ItemCountError {added, expected} => write!( f, "added item count should equal static size given to builder (added: {}, expected: {})", added, expected ), StaticAABB2DIndexBuildError::NumericCastError => write!( f, "numeric cast to/from type T to u16 failed (may be due to overflow/underflow)" ), } } } /// Simple 2D axis aligned bounding box which holds the extents of a 2D box. #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)] pub struct AABB<T = f64> { /// Min x extent of the axis aligned bounding box. pub min_x: T, /// Min y extent of the axis aligned bounding box. pub min_y: T, /// Max x extent of the axis aligned bounding box. pub max_x: T, /// Max y extent of the axis aligned bounding box. pub max_y: T, } impl<T> Default for AABB<T> where T: IndexableNum, { #[inline(always)] fn default() -> Self { AABB { min_x: T::zero(), min_y: T::zero(), max_x: T::zero(), max_y: T::zero(), } } } impl<T> AABB<T> where T: IndexableNum, { #[inline(always)] pub fn new(min_x: T, min_y: T, max_x: T, max_y: T) -> AABB<T> { AABB { min_x, min_y, max_x, max_y, } } /// Tests if this AABB overlaps another AABB (inclusive). /// /// # Examples /// ``` /// use static_aabb2d_index::AABB; /// let box_a = AABB::new(0, 0, 2, 2); /// let box_b = AABB::new(1, 1, 3, 3); /// assert!(box_a.overlaps_aabb(&box_b)); /// assert!(box_b.overlaps_aabb(&box_a)); /// /// let box_c = AABB::new(-1, -1, 0, 0); /// assert!(!box_c.overlaps_aabb(&box_b)); /// // note: overlap check is inclusive of edges/corners touching /// assert!(box_c.overlaps_aabb(&box_a)); /// ``` #[inline(always)] pub fn overlaps_aabb(&self, other: &AABB<T>) -> bool { self.overlaps(other.min_x, other.min_y, other.max_x, other.max_y) } /// Tests if this AABB overlaps another AABB. /// Same as [AABB::overlaps_aabb] but accepts AABB extent parameters directly. #[inline(always)] pub fn overlaps(&self, min_x: T, min_y: T, max_x: T, max_y: T) -> bool { if self.max_x < min_x || self.max_y < min_y || self.min_x > max_x || self.min_y > max_y { return false; } true } /// Tests if this AABB fully contains another AABB (inclusive). /// /// # Examples /// ``` /// use static_aabb2d_index::AABB; /// let box_a = AABB::new(0, 0, 3, 3); /// let box_b = AABB::new(1, 1, 2, 2); /// assert!(box_a.contains_aabb(&box_b)); /// assert!(!box_b.contains_aabb(&box_a)); /// ``` #[inline(always)] pub fn contains_aabb(&self, other: &AABB<T>) -> bool { self.contains(other.min_x, other.min_y, other.max_x, other.max_y) } /// Tests if this AABB fully contains another AABB. /// Same as [AABB::contains] but accepts AABB extent parameters directly. #[inline(always)] pub fn contains(&self, min_x: T, min_y: T, max_x: T, max_y: T) -> bool { self.min_x <= min_x && self.min_y <= min_y && self.max_x >= max_x && self.max_y >= max_y } } /// Used to build a [StaticAABB2DIndex]. #[derive(Debug, Clone)] pub struct StaticAABB2DIndexBuilder<T = f64> where T: IndexableNum, { min_x: T, min_y: T, max_x: T, max_y: T, node_size: usize, num_items: usize, level_bounds: Vec<usize>, /// boxes holds the tree data (all nodes and items) boxes: Vec<AABB<T>>, /// indices is used to map from sorted indices to indices ordered according to the order items were added indices: Vec<usize>, // used to keep track of the current position for boxes added pos: usize, } /// Static/fixed size indexing data structure for two dimensional axis aligned bounding boxes. /// /// The index allows for fast construction and fast querying but cannot be modified after creation. /// This type is constructed from a [StaticAABB2DIndexBuilder]. /// /// 2D axis aligned bounding boxes are represented by two extent points (four values): (min_x, min_y), (max_x, max_y). /// /// # Examples /// ``` /// use static_aabb2d_index::*; /// // create builder for index containing 4 axis aligned bounding boxes /// // index also supports integers and custom types that implement the IndexableNum trait /// let mut builder: StaticAABB2DIndexBuilder<f64> = StaticAABB2DIndexBuilder::new(4); /// // add bounding boxes to the index /// // add takes in (min_x, min_y, max_x, max_y) of the bounding box /// builder.add(0.0, 0.0, 2.0, 2.0); /// builder.add(-1.0, -1.0, 3.0, 3.0); /// builder.add(0.0, 0.0, 1.0, 3.0); /// builder.add(4.0, 2.0, 16.0, 8.0); /// // note build may return an error if the number of added boxes does not equal the static size /// // given at the time the builder was created or the type used fails to cast to/from a u16 /// let index: StaticAABB2DIndex<f64> = builder.build().unwrap(); /// // query the created index (min_x, min_y, max_x, max_y) /// let query_results = index.query(-1.0, -1.0, -0.5, -0.5); /// // query_results holds the index positions of the boxes that overlap with the box given /// // (positions are according to the order boxes were added the index builder) /// assert_eq!(query_results, vec![1]); /// // the query may also be done with a visiting function that can stop the query early /// let mut visited_results: Vec<usize> = Vec::new(); /// let mut visitor = |box_added_pos: usize| -> bool { /// visited_results.push(box_added_pos); /// // return true to continue visiting results, false to stop early /// true /// }; /// /// index.visit_query(-1.0, -1.0, -0.5, -0.5, &mut visitor); /// assert_eq!(visited_results, vec![1]); /// ``` #[derive(Debug, Clone)] pub struct StaticAABB2DIndex<T = f64> where T: IndexableNum, { min_x: T, min_y: T, max_x: T, max_y: T, node_size: usize, num_items: usize, level_bounds: Vec<usize>, /// boxes holds the tree data (all nodes and items) boxes: Vec<AABB<T>>, /// indices is used to map from sorted indices to indices ordered according to the order items were added indices: Vec<usize>, } // get_at_index! and set_at_index! macros to toggle bounds checking at compile time #[cfg(not(feature = "allow_unsafe"))] macro_rules! get_at_index { ($container:expr, $index:expr) => { &$container[$index] }; } #[cfg(feature = "allow_unsafe")] macro_rules! get_at_index { ($container:expr, $index:expr) => { unsafe { $container.get_unchecked($index) } }; } #[cfg(not(feature = "allow_unsafe"))] macro_rules! set_at_index { ($container:expr, $index:expr, $value:expr) => { $container[$index] = $value }; } #[cfg(feature = "allow_unsafe")] macro_rules! set_at_index { ($container:expr, $index:expr, $value:expr) => { unsafe { *$container.get_unchecked_mut($index) = $value } }; } impl<T> StaticAABB2DIndexBuilder<T> where T: IndexableNum, { fn init(num_items: usize, node_size: usize) -> Self { let node_size = min(max(node_size, 2), 65535); let mut n = num_items; let mut num_nodes = num_items; let mut level_bounds: Vec<usize> = Vec::new(); level_bounds.push(n); // calculate the total number of nodes in the R-tree to allocate space for // and the index of each tree level (level_bounds, used in search later) loop { n = (n as f64 / node_size as f64).ceil() as usize; num_nodes += n; level_bounds.push(num_nodes); if n == 1 { break; } } // unsafe alternative for performance (uninitialized memory rather than initialize to zero) // since it is all initialized later before use #[cfg(feature = "allow_unsafe")] let init_boxes = || { let mut boxes = Vec::with_capacity(num_nodes); unsafe { boxes.set_len(num_nodes); } boxes }; #[cfg(not(feature = "allow_unsafe"))] let init_boxes = || vec![AABB::default(); num_nodes]; let boxes = init_boxes(); StaticAABB2DIndexBuilder { min_x: T::max_value(), min_y: T::max_value(), max_x: T::min_value(), max_y: T::min_value(), node_size, num_items, level_bounds, boxes, indices: (0..num_nodes).collect(), pos: 0, } } /// Construct a new [StaticAABB2DIndexBuilder] to fit exactly the specified `count` number of items. #[inline(always)] pub fn new(count: usize) -> Self { StaticAABB2DIndexBuilder::init(count, 16) } /// Construct a new [StaticAABB2DIndexBuilder] to fit exactly the specified `count` number of items and use `node_size` for the index tree shape. /// /// Each node in the index tree has a maximum size which may be adjusted by `node_size` for performance reasons, however the default value of 16 when /// calling `StaticAABB2DIndexBuilder::new` is tested to be optimal in most cases. /// /// If `node_size` is less than 2 then 2 is used, if `node_size` is greater than 65535 then 65535 is used. #[inline(always)] pub fn new_with_node_size(count: usize, node_size: usize) -> Self { StaticAABB2DIndexBuilder::init(count, node_size) } /// Add an axis aligned bounding box with the extent points (`min_x`, `min_y`), (`max_x`, `max_y`) to the index. /// /// For performance reasons the sanity checks of `min_x <= max_x` and `min_y <= max_y` are only debug asserted. /// If an invalid box is added it may lead to a panic or unexpected behavior from the constructed [StaticAABB2DIndex]. pub fn add(&mut self, min_x: T, min_y: T, max_x: T, max_y: T) -> &mut Self { // catch adding past num_items (error will be returned when build is called) if self.pos >= self.num_items { self.pos += 1; return self; } debug_assert!(min_x <= max_x); debug_assert!(min_y <= max_y); set_at_index!(self.boxes, self.pos, AABB::new(min_x, min_y, max_x, max_y)); self.pos += 1; self.min_x = T::min(self.min_x, min_x); self.min_y = T::min(self.min_y, min_y); self.max_x = T::max(self.max_x, max_x); self.max_y = T::max(self.max_y, max_y); self } /// Build the [StaticAABB2DIndex] with the boxes that have been added. /// /// If the number of added items does not match the count given at the time the builder was created then /// a [StaticAABB2DIndexBuildError::ItemCountError] will be returned. /// /// If the numeric type T fails to cast to/from a u16 for any reason then a /// [StaticAABB2DIndexBuildError::NumericCastError] will be returned. pub fn build(mut self) -> Result<StaticAABB2DIndex<T>, StaticAABB2DIndexBuildError> { if self.pos != self.num_items { return Err(StaticAABB2DIndexBuildError::ItemCountError { added: self.pos, expected: self.num_items, }); } // if number of items is less than node size then skip sorting since each node of boxes must be // fully scanned regardless and there is only one node if self.num_items <= self.node_size { set_at_index!(self.indices, self.pos, 0); // fill root box with total extents set_at_index!( self.boxes, self.pos, AABB::new(self.min_x, self.min_y, self.max_x, self.max_y) ); return Ok(StaticAABB2DIndex { min_x: self.min_x, min_y: self.min_y, max_x: self.max_x, max_y: self.max_y, node_size: self.node_size, num_items: self.num_items, level_bounds: self.level_bounds, boxes: self.boxes, indices: self.indices, }); } let width = self.max_x - self.min_x; let height = self.max_y - self.min_y; // hilbert max input value for x and y let hilbert_max = T::from(u16::MAX).ok_or(StaticAABB2DIndexBuildError::NumericCastError)?; let two = T::from(2u16).ok_or(StaticAABB2DIndexBuildError::NumericCastError)?; // mapping the x and y coordinates of the center of the item boxes to values in the range // [0 -> n - 1] such that the min of the entire set of bounding boxes maps to 0 and the max of // the entire set of bounding boxes maps to n - 1 our 2d space is x: [0 -> n-1] and // y: [0 -> n-1], our 1d hilbert curve value space is d: [0 -> n^2 - 1] let mut hilbert_values: Vec<u32> = Vec::with_capacity(self.num_items); for aabb in self.boxes.iter().take(self.num_items) { let x = if width == T::zero() { 0 } else { (hilbert_max * ((aabb.min_x + aabb.max_x) / two - self.min_x) / width) .to_u16() .ok_or(StaticAABB2DIndexBuildError::NumericCastError)? }; let y = if height == T::zero() { 0 } else { (hilbert_max * ((aabb.min_y + aabb.max_y) / two - self.min_y) / height) .to_u16() .ok_or(StaticAABB2DIndexBuildError::NumericCastError)? }; hilbert_values.push(hilbert_xy_to_index(x, y)); } // sort items by their Hilbert value for constructing the tree sort( &mut hilbert_values, &mut self.boxes, &mut self.indices, 0, self.num_items - 1, self.node_size, ); // generate nodes at each tree level, bottom-up let mut pos = 0; for i in 0..self.level_bounds.len() - 1 { let end = *get_at_index!(self.level_bounds, i); // generate a parent node for each block of consecutive node_size nodes while pos < end { let mut node_min_x = T::max_value(); let mut node_min_y = T::max_value(); let mut node_max_x = T::min_value(); let mut node_max_y = T::min_value(); let node_index = pos; // calculate bounding box for the new node let mut j = 0; while j < self.node_size && pos < end { let aabb = get_at_index!(self.boxes, pos); pos += 1; node_min_x = T::min(node_min_x, aabb.min_x); node_min_y = T::min(node_min_y, aabb.min_y); node_max_x = T::max(node_max_x, aabb.max_x); node_max_y = T::max(node_max_y, aabb.max_y); j += 1; } // add the new node to the tree set_at_index!(self.indices, self.pos, node_index); set_at_index!( self.boxes, self.pos, AABB::new(node_min_x, node_min_y, node_max_x, node_max_y) ); self.pos += 1; } } Ok(StaticAABB2DIndex { min_x: self.min_x, min_y: self.min_y, max_x: self.max_x, max_y: self.max_y, node_size: self.node_size, num_items: self.num_items, level_bounds: self.level_bounds, boxes: self.boxes, indices: self.indices, }) } } /// Maps 2d space to 1d hilbert curve space. /// /// 2d space is `x: [0 -> n-1]` and `y: [0 -> n-1]`, 1d hilbert curve value space is `d: [0 -> n^2 - 1]`, /// where n = 2^16, so `x` and `y` must be between 0 and [u16::MAX] (65535 or 2^16 - 1). pub fn hilbert_xy_to_index(x: u16, y: u16) -> u32 { let x = x as u32; let y = y as u32; // Fast Hilbert curve algorithm by http://threadlocalmutex.com/ // Ported from C++ https://github.com/rawrunprotected/hilbert_curves (public domain) let mut a_1 = x ^ y; let mut b_1 = 0xFFFF ^ a_1; let mut c_1 = 0xFFFF ^ (x | y); let mut d_1 = x & (y ^ 0xFFFF); let mut a_2 = a_1 | (b_1 >> 1); let mut b_2 = (a_1 >> 1) ^ a_1; let mut c_2 = ((c_1 >> 1) ^ (b_1 & (d_1 >> 1))) ^ c_1; let mut d_2 = ((a_1 & (c_1 >> 1)) ^ (d_1 >> 1)) ^ d_1; a_1 = a_2; b_1 = b_2; c_1 = c_2; d_1 = d_2; a_2 = (a_1 & (a_1 >> 2)) ^ (b_1 & (b_1 >> 2)); b_2 = (a_1 & (b_1 >> 2)) ^ (b_1 & ((a_1 ^ b_1) >> 2)); c_2 ^= (a_1 & (c_1 >> 2)) ^ (b_1 & (d_1 >> 2)); d_2 ^= (b_1 & (c_1 >> 2)) ^ ((a_1 ^ b_1) & (d_1 >> 2)); a_1 = a_2; b_1 = b_2; c_1 = c_2; d_1 = d_2; a_2 = (a_1 & (a_1 >> 4)) ^ (b_1 & (b_1 >> 4)); b_2 = (a_1 & (b_1 >> 4)) ^ (b_1 & ((a_1 ^ b_1) >> 4)); c_2 ^= (a_1 & (c_1 >> 4)) ^ (b_1 & (d_1 >> 4)); d_2 ^= (b_1 & (c_1 >> 4)) ^ ((a_1 ^ b_1) & (d_1 >> 4)); a_1 = a_2; b_1 = b_2; c_1 = c_2; d_1 = d_2; c_2 ^= (a_1 & (c_1 >> 8)) ^ (b_1 & (d_1 >> 8)); d_2 ^= (b_1 & (c_1 >> 8)) ^ ((a_1 ^ b_1) & (d_1 >> 8)); a_1 = c_2 ^ (c_2 >> 1); b_1 = d_2 ^ (d_2 >> 1); let mut i0 = x ^ y; let mut i1 = b_1 | (0xFFFF ^ (i0 | a_1)); i0 = (i0 | (i0 << 8)) & 0x00FF00FF; i0 = (i0 | (i0 << 4)) & 0x0F0F0F0F; i0 = (i0 | (i0 << 2)) & 0x33333333; i0 = (i0 | (i0 << 1)) & 0x55555555; i1 = (i1 | (i1 << 8)) & 0x00FF00FF; i1 = (i1 | (i1 << 4)) & 0x0F0F0F0F; i1 = (i1 | (i1 << 2)) & 0x33333333; i1 = (i1 | (i1 << 1)) & 0x55555555; (i1 << 1) | i0 } // modified quick sort that skips sorting boxes within the same node fn sort<T>( values: &mut Vec<u32>, boxes: &mut Vec<AABB<T>>, indices: &mut Vec<usize>, left: usize, right: usize, node_size: usize, ) where T: IndexableNum, { debug_assert!(left <= right); if left / node_size >= right / node_size { // remaining to be sorted fits within the the same node, skip sorting further // since all boxes within a node must be visited when querying regardless return; } let pivot = *get_at_index!(values, (left + right) >> 1); let mut i = left.wrapping_sub(1); let mut j = right.wrapping_add(1); loop { loop { i = i.wrapping_add(1); if *get_at_index!(values, i) >= pivot { break; } } loop { j = j.wrapping_sub(1); if *get_at_index!(values, j) <= pivot { break; } } if i >= j { break; } swap(values, boxes, indices, i, j); } sort(values, boxes, indices, left, j, node_size); sort(values, boxes, indices, j.wrapping_add(1), right, node_size); } #[inline] fn swap<T>( values: &mut Vec<u32>, boxes: &mut Vec<AABB<T>>, indices: &mut Vec<usize>, i: usize, j: usize, ) where T: IndexableNum, { values.swap(i, j); boxes.swap(i, j); indices.swap(i, j); } struct QueryIterator<'a, T> where T: IndexableNum, { aabb_index: &'a StaticAABB2DIndex<T>, stack: Vec<usize>, min_x: T, min_y: T, max_x: T, max_y: T, node_index: usize, level: usize, pos: usize, end: usize, } impl<'a, T> QueryIterator<'a, T> where T: IndexableNum, { #[inline] fn new( aabb_index: &'a StaticAABB2DIndex<T>, min_x: T, min_y: T, max_x: T, max_y: T, ) -> QueryIterator<'a, T> { let node_index = aabb_index.boxes.len() - 1; let pos = node_index; let level = aabb_index.level_bounds.len() - 1; let end = min( node_index + aabb_index.node_size, *get_at_index!(aabb_index.level_bounds, level), ); QueryIterator { aabb_index, stack: Vec::with_capacity(16), min_x, min_y, max_x, max_y, node_index, level, pos, end, } } } impl<'a, T> Iterator for QueryIterator<'a, T> where T: IndexableNum, { type Item = usize; // NOTE: The inline attribute here shows significant performance improvements in benchmarks. #[inline] fn next(&mut self) -> Option<Self::Item> { loop { while self.pos < self.end { let current_pos = self.pos; self.pos += 1; let aabb = get_at_index!(self.aabb_index.boxes, current_pos); if !aabb.overlaps(self.min_x, self.min_y, self.max_x, self.max_y) { // no overlap continue; } let index = *get_at_index!(self.aabb_index.indices, current_pos); if self.node_index < self.aabb_index.num_items { return Some(index); } else { self.stack.push(index); self.stack.push(self.level - 1); } } if self.stack.len() > 1 { self.level = self.stack.pop().unwrap(); self.node_index = self.stack.pop().unwrap(); self.pos = self.node_index; self.end = min( self.node_index + self.aabb_index.node_size, *get_at_index!(self.aabb_index.level_bounds, self.level), ); } else { return None; } } } } impl<T> StaticAABB2DIndex<T> where T: IndexableNum, { /// Gets the min_x extent value of the all the bounding boxes in the index. #[inline(always)] pub fn min_x(&self) -> T { self.min_x } /// Gets the min_y extent value of the all the bounding boxes in the index. #[inline(always)] pub fn min_y(&self) -> T { self.min_y } /// Gets the max_x extent value of the all the bounding boxes in the index. #[inline(always)] pub fn max_x(&self) -> T { self.max_x } /// Gets the max_y extent value of the all the bounding boxes in the index. #[inline(always)] pub fn max_y(&self) -> T { self.max_y } /// Gets the total count of items that were added to the index. #[inline(always)] pub fn count(&self) -> usize { self.num_items } /// Queries the index, returning a collection of indexes to items that overlap with the bounding box given. /// /// `min_x`, `min_y`, `max_x`, and `max_y` represent the bounding box to use for the query. Indexes returned /// match with the order items were added to the index using [StaticAABB2DIndexBuilder::add]. #[inline(always)] pub fn query(&self, min_x: T, min_y: T, max_x: T, max_y: T) -> Vec<usize> { let mut results = Vec::new(); let mut visitor = |i| { results.push(i); true }; self.visit_query(min_x, min_y, max_x, max_y, &mut visitor); results } /// The same as [StaticAABB2DIndex::query] but instead of returning a [Vec] of results a lazy iterator is returned /// which yields the results. /// /// # Examples /// ``` /// use static_aabb2d_index::*; /// let mut builder = StaticAABB2DIndexBuilder::new(4); /// builder /// .add(0.0, 0.0, 2.0, 2.0) /// .add(-1.0, -1.0, 3.0, 3.0) /// .add(0.0, 0.0, 1.0, 3.0) /// .add(4.0, 2.0, 16.0, 8.0); /// let index = builder.build().unwrap(); /// let query_results = index.query_iter(-1.0, -1.0, -0.5, -0.5).collect::<Vec<usize>>(); /// assert_eq!(query_results, vec![1]); /// ``` #[inline(always)] pub fn query_iter<'a>( &'a self, min_x: T, min_y: T, max_x: T, max_y: T, ) -> impl Iterator<Item = usize> + 'a { QueryIterator::<'a, T>::new(&self, min_x, min_y, max_x, max_y) } /// Same as [StaticAABB2DIndex::query] but instead of returning a collection of indexes a `visitor` /// function is called for each index that would be returned. /// The `visitor` returns a bool indicating whether to continue visiting (true) or not (false). #[inline(always)] pub fn visit_query<F>(&self, min_x: T, min_y: T, max_x: T, max_y: T, visitor: &mut F) where F: FnMut(usize) -> bool, { let mut stack: Vec<usize> = Vec::with_capacity(16); self.visit_query_with_stack(min_x, min_y, max_x, max_y, visitor, &mut stack); } /// Returns all the item [AABB] that were added to the index by [StaticAABB2DIndexBuilder::add]. /// /// Use [StaticAABB2DIndex::map_all_boxes_index] to map a box back to the original index position it was added. #[inline(always)] pub fn item_boxes(&self) -> &[AABB<T>] { &self.boxes[0..self.num_items] } /// Gets the node size used for the [StaticAABB2DIndex]. /// /// The node size is the maximum number of boxes stored as children of each node in the index tree. #[inline(always)] pub fn node_size(&self) -> usize { self.node_size } /// Gets the level bounds for all the boxes in the [StaticAABB2DIndex]. /// /// The level bounds are the index positions in [StaticAABB2DIndex::all_boxes] where a change in the level of the index tree occurs. #[inline(always)] pub fn level_bounds(&self) -> &[usize] { &self.level_bounds } /// Gets all the bounding boxes for the [StaticAABB2DIndex]. /// /// The boxes are ordered from the bottom of the tree up, so from 0 to [StaticAABB2DIndex::count] are all the item bounding boxes. /// Use [StaticAABB2DIndex::map_all_boxes_index] to map a box back to the original index position it was added or find the start /// position for the children of a node box. #[inline(always)] pub fn all_boxes(&self) -> &[AABB<T>] { &self.boxes } /// Gets the original item index position (from the time it was added) from a [StaticAABB2DIndex::all_boxes] /// slice index position. /// /// If `all_boxes_index` is greater than [StaticAABB2DIndex::count] then it will return the /// [StaticAABB2DIndex::all_boxes] starting index of the node's children boxes. /// See the index_tree_structure.rs example for more information. #[inline(always)] pub fn map_all_boxes_index(&self, all_boxes_index: usize) -> usize { self.indices[all_boxes_index] } /// Same as [StaticAABB2DIndex::query] but accepts an existing [Vec] to be used as a stack buffer when /// performing the query to avoid the need for allocation (this is for performance benefit only). #[inline(always)] pub fn query_with_stack( &self, min_x: T, min_y: T, max_x: T, max_y: T, stack: &mut Vec<usize>, ) -> Vec<usize> { let mut results = Vec::new(); let mut visitor = |i| { results.push(i); true }; self.visit_query_with_stack(min_x, min_y, max_x, max_y, &mut visitor, stack); results } /// Same as [StaticAABB2DIndex::visit_query] but accepts an existing [Vec] to be used as a stack buffer /// when performing the query to avoid the need for allocation (this is for performance benefit only). pub fn visit_query_with_stack<F>( &self, min_x: T, min_y: T, max_x: T, max_y: T, visitor: &mut F, stack: &mut Vec<usize>, ) where F: FnMut(usize) -> bool, { let mut node_index = self.boxes.len() - 1; let mut level = self.level_bounds.len() - 1; stack.clear(); 'search_loop: loop { let end = min( node_index + self.node_size, *get_at_index!(self.level_bounds, level), ); for pos in node_index..end { let aabb = get_at_index!(self.boxes, pos); if !aabb.overlaps(min_x, min_y, max_x, max_y) { // no overlap continue; } let index = *get_at_index!(self.indices, pos); if node_index < self.num_items { if !visitor(index) { break 'search_loop; } } else { stack.push(index); stack.push(level - 1); } } if stack.len() > 1 { level = stack.pop().unwrap(); node_index = stack.pop().unwrap(); } else { break 'search_loop; } } } }