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author Gone2Daly <71726742+Gone2Daly@users.noreply.github.com>2023-07-22 21:05:42 +0200
committer Gone2Daly <71726742+Gone2Daly@users.noreply.github.com>2023-07-22 21:05:42 +0200
commit71b3cd829f80de4c2cd3972d8bfd5ee470a5d180 (patch)
treeb4280fde6eef2ae6987648bc7bf8e00e9011bb7f /game/addons/zylann.hterrain/native/src/quad_tree_lod.cpp
parentce9022d0df74d6c33db3686622be2050d873ab0b (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.cpp242
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