move walkable region calculation to class chunk

6 files changed, 223 insertions, 12 deletions

diff --git a/src/chunk-region.cpp b/src/chunk-region.cpp
new file mode 100644
index 00000000..2c290dee
--- /dev/null
+++ b/src/chunk-region.cpp
@@ -0,0 +1,179 @@
+#include "chunk-region.hpp"
+#include "path-search-bbox.hpp"
+#include "world.hpp"
+#include <Corrade/Containers/GrowableArray.h>
+#include <Magnum/Math/Functions.h>
+
+namespace floormat {
+
+namespace {
+
+using detail_astar::bbox;
+using detail_astar::div_factor;
+using detail_astar::div_size;
+using detail_astar::div_count;
+
+static_assert(div_count.x() == div_count.y());
+static_assert((iTILE_SIZE2 % div_size).isZero());
+
+constexpr auto chunk_bits = div_count.product(),
+               visited_bits = div_count.product()*4*4;
+constexpr auto div_min = -iTILE_SIZE2/2 + div_size/2,
+               div_max = iTILE_SIZE2 * TILE_MAX_DIM - iTILE_SIZE2/2 - div_size + div_size/2;
+
+constexpr bbox<Int> bbox_from_pos1(Vector2i center)
+{
+    constexpr auto half = div_size/2;
+    auto start = center - half;
+    return { start, start + div_size };
+}
+
+constexpr bbox<Int> bbox_from_pos2(Vector2i pt, Vector2i from)
+{
+    auto bb0 = bbox_from_pos1(from);
+    auto bb = bbox_from_pos1(pt);
+    auto min = Math::min(bb0.min, bb.min);
+    auto max = Math::max(bb0.max, bb.max);
+    return { min, max };
+}
+
+constexpr bbox<Int> make_pos(Vector2i ij, Vector2i from)
+{
+    auto pos = div_min + div_size * ij;
+    auto pos0 = pos + from*div_size;
+    return bbox_from_pos2(pos, pos0);
+}
+
+bool check_pos(chunk& c, const std::array<chunk*, 8>& nbs, Vector2i ij, Vector2i from)
+{
+    auto pos = make_pos(ij, from);
+    bool ret = path_search::is_passable_(&c, nbs, Vector2(pos.min), Vector2(pos.max), 0);
+    //if (ret) Debug{} << "check" << ij << ij/div_factor << ij % div_factor << pos.min << pos.max << ret;
+    //Debug{} << "check" << ij << pos.min << pos.max << ret;
+    return ret;
+}
+
+struct node_s
+{
+    Vector2i pos;
+};
+
+struct tmp_s
+{
+    Array<node_s> stack;
+    std::bitset<visited_bits> visited;
+
+    static uint32_t get_index(Vector2i pos);
+    void append(std::bitset<chunk_bits>& passable, Vector2i pos);
+    [[nodiscard]] bool check_visited(std::bitset<chunk_bits>& passable, Vector2i pos, int from);
+    void clear();
+};
+
+uint32_t tmp_s::get_index(Vector2i pos)
+{
+    return (uint32_t)pos.y() * (uint32_t)div_count.x() + (uint32_t)pos.x();
+}
+
+void tmp_s::append(std::bitset<chunk_bits>& passable, Vector2i pos)
+{
+    auto i = get_index(pos);
+    passable[i] = true;
+    arrayAppend(stack, {pos});
+}
+
+bool tmp_s::check_visited(std::bitset<chunk_bits>& passable, Vector2i pos, int from)
+{
+    auto i = get_index(pos);
+    //fm_debug_assert(i < passable.size());
+    if (passable[i])
+        return {};
+    auto v = i*4 + (uint32_t)from;
+    //fm_debug_assert(v < visited.size());
+    if (visited[v])
+        return {};
+    visited[v] = true;
+    return true;
+}
+
+void tmp_s::clear()
+{
+    arrayResize(stack, 0);
+    visited = {};
+}
+
+tmp_s& get_tmp()
+{
+    static Pointer<tmp_s> tmp = [] {
+        Pointer<tmp_s> p{InPlace};
+        arrayReserve(p->stack, 4*div_count.product());
+        return p;
+    }();
+    arrayResize(tmp->stack, 0);
+    tmp->visited = {};
+    return *tmp;
+}
+
+} // namespace
+
+void chunk::delete_pass_region(pass_region*& ptr)
+{
+    if (ptr)
+    {
+        delete ptr;
+        ptr = nullptr;
+    }
+}
+
+auto chunk::get_pass_region() -> const pass_region*
+{
+    if (!_region_modified)
+    {
+        fm_debug_assert(_region != nullptr);
+        return _region;
+    }
+
+    if (!_region)
+        _region = new pass_region;
+    else
+        _region->bits = {};
+
+    make_pass_region(*_region);
+    return _region;
+}
+
+bool chunk::is_region_modified() const noexcept { return _region_modified; }
+void chunk::mark_region_modified() noexcept { _region_modified = true; }
+
+void chunk::make_pass_region(pass_region& ret)
+{
+    auto& tmp = get_tmp();
+    const auto nbs = _world->neighbors(_coord);
+
+    constexpr Vector2i fours[4] = { {0, 1}, {0, -1}, {1, 0}, {-1, 0} };
+    constexpr auto last = div_count - Vector2i{1};
+    //if (Vector2i pos{0, 0}; check_pos(*c, nbs, pos, fours[1])) tmp.append(pos, 1); // top
+
+    for (int i = 0; i < div_count.x(); i++)
+    {
+        if (Vector2i pos{i, last.y()}; check_pos(*this, nbs, pos, fours[0])) tmp.append(ret.bits, pos); // bottom
+        if (Vector2i pos{i, 0};        check_pos(*this, nbs, pos, fours[1])) tmp.append(ret.bits, pos); // top
+        if (Vector2i pos{last.x(), i}; check_pos(*this, nbs, pos, fours[2])) tmp.append(ret.bits, pos); // right
+        if (Vector2i pos{0, i};        check_pos(*this, nbs, pos, fours[3])) tmp.append(ret.bits, pos); // left
+    }
+
+    while (!tmp.stack.isEmpty())
+    {
+        auto p = tmp.stack.back().pos;
+        arrayRemoveSuffix(tmp.stack);
+        for (int i = 0; i < 4; i++)
+        {
+            Vector2i from = fours[i], pos{p - from};
+            if ((uint32_t)pos.x() >= div_count.x() || (uint32_t)pos.y() >= div_count.y()) [[unlikely]]
+                continue;
+            if (tmp.check_visited(ret.bits, pos, i) && check_pos(*this, nbs, pos, from))
+                tmp.append(ret.bits, pos);
+        }
+    }
+}
+
+} // namespace floormat
diff --git a/src/chunk-region.hpp b/src/chunk-region.hpp
new file mode 100644
index 00000000..5720e93e
--- /dev/null
+++ b/src/chunk-region.hpp
@@ -0,0 +1,13 @@
+#pragma once
+#include "chunk.hpp"
+#include "path-search.hpp"
+#include <bitset>
+
+namespace floormat {
+
+struct chunk::pass_region
+{
+    std::bitset<detail_astar::div_count.product()> bits;
+};
+
+} // namespace floormat
diff --git a/src/chunk.cpp b/src/chunk.cpp
index 4963a9e7..1a727599 100644
--- a/src/chunk.cpp
+++ b/src/chunk.cpp
@@ -152,6 +152,7 @@ chunk::~chunk() noexcept
     arrayResize(_objects, 0);
     arrayShrink(_objects);
     _rtree->RemoveAll();
+    delete_pass_region(_region);
 }
 
 chunk::chunk(chunk&&) noexcept = default;
@@ -162,10 +163,12 @@ bool chunk::bbox::operator==(const bbox& other) const noexcept = default;
 void chunk::add_object_unsorted(const std::shared_ptr<object>& e)
 {
     _objects_sorted = false;
+    _region_modified = true;
     if (!e->is_dynamic())
         mark_scenery_modified();
     if (bbox bb; _bbox_for_scenery(*e, bb))
         _add_bbox(bb);
+    arrayReserve(_objects, 8);
     arrayAppend(_objects, e);
 }
 
@@ -173,10 +176,8 @@ void chunk::sort_objects()
 {
     if (_objects_sorted)
         return;
-
     _objects_sorted = true;
     mark_scenery_modified();
-
     std::sort(_objects.begin(), _objects.end(), [](const auto& a, const auto& b) {
         return a->id < b->id;
     });
@@ -185,10 +186,12 @@ void chunk::sort_objects()
 void chunk::add_object(const std::shared_ptr<object>& e)
 {
     fm_assert(_objects_sorted);
+    _region_modified = true;
     if (!e->is_dynamic())
         mark_scenery_modified();
     if (bbox bb; _bbox_for_scenery(*e, bb))
         _add_bbox(bb);
+    arrayReserve(_objects, 8);
     auto& es = _objects;
     auto it = std::lower_bound(es.cbegin(), es.cend(), e, object_id_lessp);
     arrayInsert(es, (size_t)std::distance(es.cbegin(), it), e);
@@ -197,6 +200,7 @@ void chunk::add_object(const std::shared_ptr<object>& e)
 void chunk::remove_object(size_t i)
 {
     fm_assert(_objects_sorted);
+    _region_modified = true;
     auto& es = _objects;
     fm_debug_assert(i < es.size());
     const auto e = es[i];
diff --git a/src/chunk.hpp b/src/chunk.hpp
index 3e142abf..5404d25b 100644
--- a/src/chunk.hpp
+++ b/src/chunk.hpp
@@ -27,6 +27,7 @@ public:
     friend struct tile_ref;
     friend struct object;
     friend class world;
+    struct pass_region;
 
     tile_ref operator[](size_t idx) noexcept;
     tile_proto operator[](size_t idx) const noexcept;
@@ -62,10 +63,12 @@ public:
     void mark_walls_modified() noexcept;
     void mark_scenery_modified() noexcept;
     void mark_passability_modified() noexcept;
+    void mark_region_modified() noexcept;
     void mark_modified() noexcept;
 
     bool is_passability_modified() const noexcept;
     bool is_scenery_modified() const noexcept;
+    bool is_region_modified() const noexcept;
 
     struct ground_mesh_tuple final {
         GL::Mesh& mesh;
@@ -116,6 +119,9 @@ public:
     static constexpr size_t max_wall_quad_count =
         TILE_COUNT*Wall::Direction_COUNT*(Wall::Group_COUNT+4);
 
+    const pass_region* get_pass_region();
+    void make_pass_region(pass_region& ret);
+
 private:
     struct ground_stuff
     {
@@ -133,23 +139,27 @@ private:
 
     Pointer<ground_stuff> _ground;
     Pointer<wall_stuff> _walls;
+    pass_region* _region = nullptr;
     Array<std::shared_ptr<object>> _objects;
     class world* _world;
     GL::Mesh ground_mesh{NoCreate}, wall_mesh{NoCreate}, scenery_mesh{NoCreate};
     Pointer<RTree> _rtree;
     chunk_coords_ _coord;
 
-    mutable bool _maybe_empty            : 1 = true,
-                 _ground_modified        : 1 = true,
-                 _walls_modified         : 1 = true,
-                 _scenery_modified       : 1 = true,
-                 _pass_modified          : 1 = true,
-                 _teardown               : 1 = false,
-                 _objects_sorted         : 1 = true;
+    mutable bool _maybe_empty      : 1 = true,
+                 _ground_modified  : 1 = true,
+                 _walls_modified   : 1 = true,
+                 _scenery_modified : 1 = true,
+                 _pass_modified    : 1 = true,
+                 _region_modified  : 1 = true,
+                 _teardown         : 1 = false,
+                 _objects_sorted   : 1 = true;
 
     void ensure_scenery_buffers(scenery_scratch_buffers bufs);
     static topo_sort_data make_topo_sort_data(object& e, uint32_t mesh_idx);
 
+    static void delete_pass_region(pass_region*& ptr);
+
     struct bbox final // NOLINT(cppcoreguidelines-pro-type-member-init)
     {
         object_id id;
diff --git a/src/object.cpp b/src/object.cpp
index 52244121..34659aa5 100644
--- a/src/object.cpp
+++ b/src/object.cpp
@@ -72,6 +72,7 @@ object::~object() noexcept
     if (chunk::bbox bb; c->_bbox_for_scenery(*this, bb))
         c->_remove_bbox(bb);
     c->_world->do_kill_object(id);
+    c->mark_region_modified();
     const_cast<object_id&>(id) = 0;
 }
 
@@ -244,6 +245,7 @@ void object::move_to(size_t& i, Vector2i delta, rotation new_r)
     if (coord_.chunk() == coord.chunk())
     {
         c->_replace_bbox(bb0, bb1, b0, b1);
+        c->mark_region_modified();
         const_cast<global_coords&>(coord) = coord_;
         set_bbox_(offset_, bb_offset, bb_size, pass);
         const_cast<rotation&>(r) = new_r;
@@ -255,6 +257,7 @@ void object::move_to(size_t& i, Vector2i delta, rotation new_r)
             c2.mark_scenery_modified();
         c2._add_bbox(bb1);
         c->remove_object(i);
+        c->mark_region_modified();
         auto& es = c2._objects;
         auto it = std::lower_bound(es.cbegin(), es.cend(), e_, object_id_lessp);
         const_cast<global_coords&>(coord) = coord_;
@@ -306,6 +309,7 @@ void object::set_bbox(Vector2b offset_, Vector2b bb_offset_, Vector2ub bb_size_,
     set_bbox_(offset_, bb_offset_, bb_size_, pass);
     const bool b = c->_bbox_for_scenery(*this, bb);
     c->_replace_bbox(bb0, bb, b0, b);
+    c->mark_region_modified();
 }
 
 bool object::can_activate(size_t) const { return false; }
diff --git a/src/path-search.hpp b/src/path-search.hpp
index c48b5532..daf3379d 100644
--- a/src/path-search.hpp
+++ b/src/path-search.hpp
@@ -20,9 +20,10 @@ namespace floormat::detail_astar {
 template<typename T> struct bbox;
 struct cache;
 struct chunk_cache;
-static constexpr int div_factor = 4;
-static constexpr auto div_size = iTILE_SIZE2 / div_factor;
-static constexpr auto min_size = Vector2ui(div_size * 2);
+constexpr inline int div_factor = 4;
+constexpr inline auto div_size = iTILE_SIZE2 / div_factor;
+constexpr inline auto min_size = Vector2ui(div_size * 2);
+constexpr inline auto div_count = iTILE_SIZE2 * TILE_MAX_DIM / detail_astar::div_size;
 
 } // namespace floormat::detail_astar