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author | Gone2Daly <71726742+Gone2Daly@users.noreply.github.com> | 2023-07-22 21:05:42 +0200 |
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committer | Gone2Daly <71726742+Gone2Daly@users.noreply.github.com> | 2023-07-22 21:05:42 +0200 |
commit | 71b3cd829f80de4c2cd3972d8bfd5ee470a5d180 (patch) | |
tree | b4280fde6eef2ae6987648bc7bf8e00e9011bb7f /game/addons/zylann.hterrain/native/src/quad_tree_lod.cpp | |
parent | ce9022d0df74d6c33db3686622be2050d873ab0b (diff) |
init_testtest3d
Diffstat (limited to 'game/addons/zylann.hterrain/native/src/quad_tree_lod.cpp')
-rw-r--r-- | game/addons/zylann.hterrain/native/src/quad_tree_lod.cpp | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/game/addons/zylann.hterrain/native/src/quad_tree_lod.cpp b/game/addons/zylann.hterrain/native/src/quad_tree_lod.cpp new file mode 100644 index 0000000..592375e --- /dev/null +++ b/game/addons/zylann.hterrain/native/src/quad_tree_lod.cpp @@ -0,0 +1,242 @@ +#include "quad_tree_lod.h" + +namespace godot { + +void QuadTreeLod::set_callbacks(Ref<FuncRef> make_cb, Ref<FuncRef> recycle_cb, Ref<FuncRef> vbounds_cb) { + _make_func = make_cb; + _recycle_func = recycle_cb; + _vertical_bounds_func = vbounds_cb; +} + +int QuadTreeLod::get_lod_count() { + // TODO make this a count, not max + return _max_depth + 1; +} + +int QuadTreeLod::get_lod_factor(int lod) { + return 1 << lod; +} + +int QuadTreeLod::compute_lod_count(int base_size, int full_size) { + int po = 0; + while (full_size > base_size) { + full_size = full_size >> 1; + po += 1; + } + return po; +} + +// The higher, the longer LODs will spread and higher the quality. +// The lower, the shorter LODs will spread and lower the quality. +void QuadTreeLod::set_split_scale(real_t p_split_scale) { + real_t MIN = 2.0f; + real_t MAX = 5.0f; + + // Split scale must be greater than a threshold, + // otherwise lods will decimate too fast and it will look messy + if (p_split_scale < MIN) + p_split_scale = MIN; + if (p_split_scale > MAX) + p_split_scale = MAX; + + _split_scale = p_split_scale; +} + +real_t QuadTreeLod::get_split_scale() { + return _split_scale; +} + +void QuadTreeLod::clear() { + _join_all_recursively(ROOT, _max_depth); + _max_depth = 0; + _base_size = 0; +} + +void QuadTreeLod::create_from_sizes(int base_size, int full_size) { + clear(); + _base_size = base_size; + _max_depth = compute_lod_count(base_size, full_size); + + // Total qty of nodes is (N^L - 1) / (N - 1). -1 for root, where N=num children, L=levels including the root + int node_count = ((static_cast<int>(pow(4, _max_depth+1)) - 1) / (4 - 1)) - 1; + _node_pool.resize(node_count); // e.g. ((4^6 -1) / 3 ) - 1 = 1364 excluding root + + _free_indices.resize((node_count / 4)); // 1364 / 4 = 341 + for (int i = 0; i < _free_indices.size(); i++) // i = 0 to 340, *4 = 0 to 1360 + _free_indices[i] = 4 * i; // _node_pool[4*0 + i0] is first child, [4*340 + i3] is last +} + +void QuadTreeLod::update(Vector3 view_pos) { + _update(ROOT, _max_depth, view_pos); + + // This makes sure we keep seeing the lowest LOD, + // if the tree is cleared while we are far away + Quad *root = _get_root(); + if (!root->has_children() && root->is_null()) + root->set_data(_make_chunk(_max_depth, 0, 0)); +} + +void QuadTreeLod::debug_draw_tree(CanvasItem *ci) { + if (ci != nullptr) + _debug_draw_tree_recursive(ci, ROOT, _max_depth, 0); +} + +// Intention is to only clear references to children +void QuadTreeLod::_clear_children(unsigned int index) { + Quad *quad = _get_node(index); + if (quad->has_children()) { + _recycle_children(quad->first_child); + quad->first_child = NO_CHILDREN; + } +} + +// Returns the index of the first_child. Allocates from _free_indices. +unsigned int QuadTreeLod::_allocate_children() { + if (_free_indices.size() == 0) { + return NO_CHILDREN; + } + + unsigned int i0 = _free_indices[_free_indices.size() - 1]; + _free_indices.pop_back(); + return i0; +} + +// Pass the first_child index, not the parent index. Stores back in _free_indices. +void QuadTreeLod::_recycle_children(unsigned int i0) { + // Debug check, there is no use case in recycling a node which is not a first child + CRASH_COND(i0 % 4 != 0); + + for (int i = 0; i < 4; ++i) { + _node_pool[i0 + i].init(); + } + + _free_indices.push_back(i0); +} + +Variant QuadTreeLod::_make_chunk(int lod, int origin_x, int origin_y) { + if (_make_func.is_valid()) { + return _make_func->call_func(origin_x, origin_y, lod); + } else { + return Variant(); + } +} + +void QuadTreeLod::_recycle_chunk(unsigned int quad_index, int lod) { + Quad *quad = _get_node(quad_index); + if (_recycle_func.is_valid()) { + _recycle_func->call_func(quad->get_data(), quad->origin_x, quad->origin_y, lod); + } +} + +void QuadTreeLod::_join_all_recursively(unsigned int quad_index, int lod) { + Quad *quad = _get_node(quad_index); + + if (quad->has_children()) { + for (int i = 0; i < 4; i++) { + _join_all_recursively(quad->first_child + i, lod - 1); + } + _clear_children(quad_index); + + } else if (quad->is_valid()) { + _recycle_chunk(quad_index, lod); + quad->clear_data(); + } +} + +void QuadTreeLod::_update(unsigned int quad_index, int lod, Vector3 view_pos) { + // This function should be called regularly over frames. + Quad *quad = _get_node(quad_index); + int lod_factor = get_lod_factor(lod); + int chunk_size = _base_size * lod_factor; + Vector3 world_center = static_cast<real_t>(chunk_size) * (Vector3(static_cast<real_t>(quad->origin_x), 0.f, static_cast<real_t>(quad->origin_y)) + Vector3(0.5f, 0.f, 0.5f)); + + if (_vertical_bounds_func.is_valid()) { + Variant result = _vertical_bounds_func->call_func(quad->origin_x, quad->origin_y, lod); + ERR_FAIL_COND(result.get_type() != Variant::VECTOR2); + Vector2 vbounds = static_cast<Vector2>(result); + world_center.y = (vbounds.x + vbounds.y) / 2.0f; + } + + int split_distance = _base_size * lod_factor * static_cast<int>(_split_scale); + + if (!quad->has_children()) { + if (lod > 0 && world_center.distance_to(view_pos) < split_distance) { + // Split + unsigned int new_idx = _allocate_children(); + ERR_FAIL_COND(new_idx == NO_CHILDREN); + quad->first_child = new_idx; + + for (int i = 0; i < 4; i++) { + Quad *child = _get_node(quad->first_child + i); + child->origin_x = quad->origin_x * 2 + (i & 1); + child->origin_y = quad->origin_y * 2 + ((i & 2) >> 1); + child->set_data(_make_chunk(lod - 1, child->origin_x, child->origin_y)); + // If the quad needs to split more, we'll ask more recycling... + } + + if (quad->is_valid()) { + _recycle_chunk(quad_index, lod); + quad->clear_data(); + } + } + } else { + bool no_split_child = true; + + for (int i = 0; i < 4; i++) { + _update(quad->first_child + i, lod - 1, view_pos); + + if (_get_node(quad->first_child + i)->has_children()) + no_split_child = false; + } + + if (no_split_child && world_center.distance_to(view_pos) > split_distance) { + // Join + for (int i = 0; i < 4; i++) { + _recycle_chunk(quad->first_child + i, lod - 1); + } + _clear_children(quad_index); + quad->set_data(_make_chunk(lod, quad->origin_x, quad->origin_y)); + } + } +} // _update + +void QuadTreeLod::_debug_draw_tree_recursive(CanvasItem *ci, unsigned int quad_index, int lod_index, int child_index) { + Quad *quad = _get_node(quad_index); + + if (quad->has_children()) { + int ch_index = quad->first_child; + for (int i = 0; i < 4; i++) { + _debug_draw_tree_recursive(ci, ch_index + i, lod_index - 1, i); + } + + } else { + real_t size = static_cast<real_t>(get_lod_factor(lod_index)); + int checker = 0; + if (child_index == 1 || child_index == 2) + checker = 1; + + int chunk_indicator = 0; + if (quad->is_valid()) + chunk_indicator = 1; + + Rect2 rect2(Vector2(static_cast<real_t>(quad->origin_x), static_cast<real_t>(quad->origin_y)) * size, + Vector2(size, size)); + Color color(1.0f - static_cast<real_t>(lod_index) * 0.2f, 0.2f * static_cast<real_t>(checker), static_cast<real_t>(chunk_indicator), 1.0f); + ci->draw_rect(rect2, color); + } +} + +void QuadTreeLod::_register_methods() { + register_method("set_callbacks", &QuadTreeLod::set_callbacks); + register_method("get_lod_count", &QuadTreeLod::get_lod_count); + register_method("get_lod_factor", &QuadTreeLod::get_lod_factor); + register_method("compute_lod_count", &QuadTreeLod::compute_lod_count); + register_method("set_split_scale", &QuadTreeLod::set_split_scale); + register_method("get_split_scale", &QuadTreeLod::get_split_scale); + register_method("clear", &QuadTreeLod::clear); + register_method("create_from_sizes", &QuadTreeLod::create_from_sizes); + register_method("update", &QuadTreeLod::update); + register_method("debug_draw_tree", &QuadTreeLod::debug_draw_tree); +} + +} // namespace godot |