feat: add cave generate

CMakeLists.txt

@@ -117,6 +117,8 @@ add_executable(${PROJECT_NAME}
     src/gameplay/builders/river_builder.cpp
     src/gameplay/builders/desert_builder.cpp
     src/gameplay/builders/forest_builder.cpp
+    src/gameplay/cave_carver.cpp
+    src/gameplay/cave_path.cpp
 )
 
 if(CMAKE_BUILD_TYPE STREQUAL "Debug")

include/Cubed/gameplay/cave_carver.hpp

@@ -0,0 +1,22 @@
+#pragma once
+#include "Cubed/gameplay/cave_path.hpp"
+namespace Cubed {
+class CaveCarver {
+public:
+    CaveCarver();
+    std::unordered_map<int, CavePath>& paths();
+    void init(unsigned world_seed);
+    void reload(unsigned world_seed);
+    void add_path(const glm::vec3& pos);
+    void try_to_add_path(const ChunkPos& pos);
+    void cleanup_finished_caves();
+
+    int cave_sum() const;
+
+private:
+    std::unordered_map<int, CavePath> m_paths;
+    unsigned m_seed = 0;
+    int m_sum = 0;
+    Random m_random;
+};
+} // namespace Cubed

include/Cubed/gameplay/cave_path.hpp

@@ -0,0 +1,67 @@
+#pragma once
+
+#include "Cubed/gameplay/chunk_pos.hpp"
+#include "Cubed/tools/cubed_random.hpp"
+
+#include <glm/glm.hpp>
+#include <unordered_set>
+namespace Cubed {
+
+struct PathPoint {
+    glm::vec3 pos;
+    glm::vec3 tangent{0.0f, 0.0f, 1.0f};
+    float rad_xz;
+    float rad_y;
+    PathPoint(const glm::vec3& p, float rx, float ry)
+        : pos(p), rad_xz(rx), rad_y(ry) {}
+    bool contains(const glm::vec3& other_pos) const {
+        glm::vec3 to_point = other_pos - pos;
+
+        glm::vec3 world_up(0.0f, 1.0f, 0.0f);
+
+        glm::vec3 right = glm::normalize(glm::cross(tangent, world_up));
+
+        if (glm::length(right) < 0.001f) {
+            glm::vec3 alt_up(1.0f, 0.0f, 0.0f);
+            right = glm::normalize(glm::cross(tangent, alt_up));
+        }
+
+        glm::vec3 up = glm::normalize(glm::cross(right, tangent));
+
+        float horizontal_dist = glm::dot(to_point, right);
+        float vertical_dist = glm::dot(to_point, up);
+
+        float a = rad_xz;
+        float b = rad_y;
+        if (a <= 0.0f || b <= 0.0f)
+            return false;
+
+        float check = (horizontal_dist * horizontal_dist) / (a * a) +
+                      (vertical_dist * vertical_dist) / (b * b);
+        return check <= 1.0f;
+    }
+};
+
+class CavePath {
+public:
+    CavePath(unsigned int world_seed, int path_id, const glm::vec3& start_pos);
+    const std::vector<PathPoint>& points() const;
+    void clear_chunk(const ChunkPos& pos);
+    bool is_finished() const;
+
+private:
+    int m_path_id = 0;
+    unsigned int m_seed = 0;
+    float m_yaw = 0.0f;
+    float m_pitch = 0.0f;
+    int m_max_step = 0;
+    float m_step_len = 1.0f;
+    PathPoint m_start_path_point{{0.0f, 0.0f, 0.0f}, 0.0f, 0.0f};
+    Random m_random;
+
+    std::vector<PathPoint> m_points;
+    std::unordered_set<ChunkPos, ChunkPos::Hash> m_pending_chunks;
+    void collect_path_points();
+    void precompute_chunk_coverage();
+};
+} // namespace Cubed

include/Cubed/gameplay/chunk.hpp

@@ -98,6 +98,7 @@ public:
     void biome(BiomeType b);
     HeightMapArray& heightmap();
     std::vector<uint8_t>& blocks();
+    World& world();
 };
 
 } // namespace Cubed

include/Cubed/gameplay/chunk_generator.hpp

@@ -55,6 +55,7 @@ private:
     bool is_cur_chunk_ins = false;
     std::array<BiomeType, 8> m_neighbor_biome;
     void make_biome_builder();
+    void generate_cave();
 };
 
 } // namespace Cubed

include/Cubed/gameplay/world.hpp

@@ -1,5 +1,6 @@
 #pragma once
 #include "Cubed/AABB.hpp"
+#include "Cubed/gameplay/cave_carver.hpp"
 #include "Cubed/gameplay/chunk.hpp"
 
 #include <atomic>
@@ -53,6 +54,8 @@ private:
     std::vector<std::pair<ChunkPos, Chunk>> m_new_chunk;
     std::vector<std::pair<ChunkPos, Chunk>> m_new_chunk_queue;
 
+    CaveCarver m_cave_carcer;
+
     void init_chunks();
 
     void gen_chunks_internal();
@@ -106,6 +109,8 @@ public:
     void rendering_distance(int rendering_distance);
     void start_gen_thread();
     void stop_gen_thread();
+
+    CaveCarver& cave_carcer();
 };
 
 } // namespace Cubed

include/Cubed/tools/cubed_hash.hpp

@@ -27,6 +27,10 @@ inline uint32_t mix_hash(int32_t a, int32_t b, uint32_t fixed_seed) {
 
     return h;
 }
+inline uint32_t combine_32(uint32_t seed, uint32_t v) {
+    seed ^= v + 0x9e3779b9 + (seed << 6) + (seed >> 2);
+    return seed;
+}
 } // namespace HASH
 
 } // namespace Cubed

include/Cubed/tools/cubed_random.hpp

@@ -11,6 +11,8 @@ public:
     unsigned seed();
 
     void init(unsigned seed);
+    int random_int(int min, int max);
+    float random_float(float min, float max);
 
 private:
     unsigned int m_seed = 0;

include/Cubed/tools/math_tools.hpp

@@ -4,8 +4,11 @@
 namespace Cubed {
 
 namespace Math {
+
 void extract_frustum_planes(const glm::mat4& mvp_matrix,
                             std::vector<glm::vec4>& planes);
-}
+
+float smootherstep(float edge0, float edge1, float x);
+} // namespace Math
 
 } // namespace Cubed

src/dev_panel.cpp

@@ -354,7 +354,8 @@ void DevPanel::show_settings_tab_item() {
 void DevPanel::show_world_tab_item() {
     if (ImGui::BeginTabItem("world")) {
         if (m_text_editing.perlin_seed) {
-            if (ImGui::InputText("Perlin Noise Seed", perlin_noise_input_buffer,
+            if (ImGui::InputText("ChunkGenerator Seed",
+                                 perlin_noise_input_buffer,
                                  sizeof(perlin_noise_input_buffer),
                                  ImGuiInputTextFlags_CallbackCharFilter |
                                      ImGuiInputTextFlags_EnterReturnsTrue,
@@ -395,6 +396,7 @@ void DevPanel::show_world_tab_item() {
                 m_app.world().stop_gen_thread();
             }
         }
+        ImGui::Text("Cave Sum %d", m_app.world().cave_carcer().cave_sum());
         ImGui::Text("Chunk Build Progress\n");
         ImGui::ProgressBar(m_app.world().chunk_gen_fraction());
         show_biome_table_bar();

src/gameplay/cave_carver.cpp

@@ -0,0 +1,54 @@
+#include "Cubed/gameplay/cave_carver.hpp"
+
+#include "Cubed/constants.hpp"
+
+namespace Cubed {
+CaveCarver::CaveCarver() {}
+
+std::unordered_map<int, CavePath>& CaveCarver::paths() { return m_paths; }
+
+void CaveCarver::init(unsigned world_seed) {
+    m_seed = world_seed;
+    m_sum = 0;
+    m_paths.emplace(m_sum,
+                    CavePath{m_seed, m_sum, glm::vec3{0.0f, 20.0f, 0.0f}});
+    m_sum++;
+    m_random.init(m_seed);
+}
+
+void CaveCarver::reload(unsigned world_seed) {
+    m_seed = world_seed;
+    m_paths.clear();
+    init(world_seed);
+}
+
+void CaveCarver::add_path(const glm::vec3& pos) {
+    m_paths.emplace(m_sum, CavePath{m_seed, m_sum, pos});
+    m_sum++;
+}
+
+void CaveCarver::try_to_add_path(const ChunkPos& chunk_pos) {
+
+    if (m_random.random_bool(0.05)) {
+        const int CHUNK_MIN_X = chunk_pos.x * CHUNK_SIZE;
+        const int CHUNK_MIN_Z = chunk_pos.z * CHUNK_SIZE;
+        const int CHUNK_MAX_X = CHUNK_MIN_X + SIZE_X - 1;
+        const int CHUNK_MAX_Z = CHUNK_MIN_Z + SIZE_Z - 1;
+        const int CHUNK_MIN_Y = 0;
+        const int CHUNK_MAX_Y = SIZE_Y - 1;
+        int max_y = std::min(CHUNK_MAX_Y, 40);
+        int x = m_random.random_int(CHUNK_MIN_X, CHUNK_MAX_X);
+        int y = m_random.random_int(CHUNK_MIN_Y + 1, max_y);
+        int z = m_random.random_int(CHUNK_MIN_Z, CHUNK_MAX_Z);
+        add_path(glm::vec3{x, y, z});
+    }
+}
+
+void CaveCarver::cleanup_finished_caves() {
+    std::erase_if(m_paths,
+                  [](const auto& kv) { return kv.second.is_finished(); });
+}
+
+int CaveCarver::cave_sum() const { return m_sum; }
+
+} // namespace Cubed

src/gameplay/cave_path.cpp

@@ -0,0 +1,82 @@
+#include "Cubed/gameplay/cave_path.hpp"
+
+#include "Cubed/constants.hpp"
+#include "Cubed/tools/cubed_hash.hpp"
+#include "Cubed/tools/math_tools.hpp"
+
+#include <algorithm>
+namespace Cubed {
+CavePath::CavePath(unsigned int world_seed, int path_id,
+                   const glm::vec3& start_pos) {
+    m_path_id = path_id;
+    m_seed = HASH::combine_32(world_seed, path_id);
+    m_random.init(m_seed);
+    m_yaw = m_random.random_float(0.0f, 360.0f);
+    m_pitch = m_random.random_float(-10.0f, 10.0f);
+    m_start_path_point.pos = start_pos;
+    m_start_path_point.rad_xz = m_random.random_float(5.0f, 15.0f);
+    m_start_path_point.rad_y = m_random.random_float(4.0f, 10.0f);
+    m_max_step = m_random.random_int(10, 400);
+    m_points.reserve(m_max_step + 1);
+    m_points.push_back(m_start_path_point);
+    collect_path_points();
+    precompute_chunk_coverage();
+}
+
+void CavePath::collect_path_points() {
+    for (int i = 0; i < m_max_step; i++) {
+
+        m_yaw = std::fmod(m_yaw, 360.0f);
+        if (m_yaw < 0.0f)
+            m_yaw += 360.0f;
+        m_pitch = std::clamp(m_pitch, -90.0f, 90.0f);
+
+        float dx = std::cos(glm::radians(m_pitch)) *
+                   std::sin(glm::radians(m_yaw)) * m_step_len;
+        float dy = std::sin(glm::radians(m_pitch)) * m_step_len;
+        float dz = std::cos(glm::radians(m_pitch)) *
+                   std::cos(glm::radians(m_yaw)) * m_step_len;
+
+        m_points[i].tangent = glm::normalize(glm::vec3{dx, dy, dz});
+
+        float t = Math::smootherstep(0, m_max_step - 1, i);
+
+        float drad_xz = m_start_path_point.rad_xz * (1.0f - t);
+        float drad_y = m_start_path_point.rad_y * (1.0f - t);
+        drad_xz = std::max(drad_xz, 4.0f);
+        drad_y = std::max(drad_y, 4.0f);
+        m_points.emplace_back(m_points[i].pos + glm::vec3{dx, dy, dz}, drad_xz,
+                              drad_y);
+
+        m_yaw += m_random.random_float(-5.0f, 5.0f);
+        m_pitch += m_random.random_float(-5.0f, 5.0f);
+    }
+    auto n = m_points.size();
+    if (n >= 2) {
+        m_points[n - 1].tangent = m_points[n - 2].tangent;
+    }
+}
+
+void CavePath::precompute_chunk_coverage() {
+    for (const auto& point : m_points) {
+        float rad = point.rad_xz;
+        const glm::vec3& center = point.pos;
+
+        int min_cx =
+            static_cast<int>(std::floor((center.x - rad) / CHUNK_SIZE));
+        int max_cx =
+            static_cast<int>(std::floor((center.x + rad) / CHUNK_SIZE));
+        int min_cz =
+            static_cast<int>(std::floor((center.z - rad) / CHUNK_SIZE));
+        int max_cz =
+            static_cast<int>(std::floor((center.z + rad) / CHUNK_SIZE));
+
+        for (int cx = min_cx; cx <= max_cx; ++cx)
+            for (int cz = min_cz; cz <= max_cz; ++cz)
+                m_pending_chunks.insert({cx, cz});
+    }
+}
+void CavePath::clear_chunk(const ChunkPos& pos) { m_pending_chunks.erase(pos); }
+const std::vector<PathPoint>& CavePath::points() const { return m_points; }
+bool CavePath::is_finished() const { return m_pending_chunks.empty(); }
+} // namespace Cubed

src/gameplay/chunk.cpp

@@ -307,4 +307,5 @@ void Chunk::biome(BiomeType b) { m_biome = b; }
 
 HeightMapArray& Chunk::heightmap() { return m_heightmap; }
 std::vector<uint8_t>& Chunk::blocks() { return m_blocks; }
+World& Chunk::world() { return m_world; }
 } // namespace Cubed

src/gameplay/chunk_generator.cpp

@@ -7,9 +7,9 @@
 #include "Cubed/gameplay/builders/river_builder.hpp"
 #include "Cubed/gameplay/chunk.hpp"
 #include "Cubed/gameplay/tree.hpp"
+#include "Cubed/gameplay/world.hpp"
 #include "Cubed/tools/cubed_hash.hpp"
 #include "Cubed/tools/perlin_noise.hpp"
-
 namespace Cubed {
 
 using enum BiomeType;
@@ -356,6 +356,7 @@ void ChunkGenerator::generate_terrain_blocks() {
     }
     m_chunk.blocks().assign(CHUNK_SIZE * CHUNK_SIZE * WORLD_SIZE_Y, 0);
     m_biome_builder->build_biome();
+    generate_cave();
 }
 
 void ChunkGenerator::blend_surface_blocks_borders(
@@ -511,6 +512,61 @@ void ChunkGenerator::make_biome_builder() {
     }
 }
 
+void ChunkGenerator::generate_cave() {
+    auto& cave_carver = m_chunk.world().cave_carcer();
+    auto& paths = cave_carver.paths();
+    const auto& chunk_pos = m_chunk.chunk_pos();
+    auto& blocks = m_chunk.blocks();
+    const int CHUNK_MIN_X = chunk_pos.x * CHUNK_SIZE;
+    const int CHUNK_MIN_Z = chunk_pos.z * CHUNK_SIZE;
+    const int CHUNK_MAX_X = CHUNK_MIN_X + SIZE_X - 1;
+    const int CHUNK_MAX_Z = CHUNK_MIN_Z + SIZE_Z - 1;
+    const int CHUNK_MIN_Y = 0;
+    const int CHUNK_MAX_Y = SIZE_Y - 1;
+    for (auto& [id, path] : paths) {
+        for (const auto& point : path.points()) {
+
+            const glm::vec3& center = point.pos;
+            float rad_xz = point.rad_xz;
+            float rad_y = point.rad_y;
+
+            int min_x = static_cast<int>(std::floor(center.x - rad_xz));
+            int max_x = static_cast<int>(std::floor(center.x + rad_xz));
+            int min_z = static_cast<int>(std::floor(center.z - rad_xz));
+            int max_z = static_cast<int>(std::floor(center.z + rad_xz));
+            int min_y = static_cast<int>(std::floor(center.y - rad_y));
+            int max_y = static_cast<int>(std::floor(center.y + rad_y));
+
+            min_x = std::max(min_x, CHUNK_MIN_X);
+            max_x = std::min(max_x, CHUNK_MAX_X);
+            min_z = std::max(min_z, CHUNK_MIN_Z);
+            max_z = std::min(max_z, CHUNK_MAX_Z);
+            min_y = std::max(min_y, CHUNK_MIN_Y);
+            max_y = std::min(max_y, CHUNK_MAX_Y);
+
+            for (int wx = min_x; wx <= max_x; ++wx) {
+                int x = wx - CHUNK_MIN_X;
+                for (int wz = min_z; wz <= max_z; ++wz) {
+                    int z = wz - CHUNK_MIN_Z;
+                    for (int wy = min_y; wy <= max_y; ++wy) {
+                        int y = wy;
+                        glm::vec3 pos(static_cast<float>(wx),
+                                      static_cast<float>(wy),
+                                      static_cast<float>(wz));
+                        if (point.contains(pos)) {
+                            if (y == 0) {
+                                continue;
+                            }
+                            blocks[Chunk::get_index(x, y, z)] = 0;
+                        }
+                    }
+                }
+            }
+        }
+        path.clear_chunk(chunk_pos);
+    }
+}
+
 Chunk& ChunkGenerator::chunk() { return m_chunk; }
 
 Random& ChunkGenerator::random() { return m_random; }

src/gameplay/player.cpp

@@ -237,10 +237,7 @@ void Player::update_front_vec(float offset_x, float offset_y) {
 
     m_yaw = std::fmod(m_yaw, 360.0);
 
-    if (m_pitch > 89.0f)
+    m_pitch = std::clamp(m_pitch, -89.0f, 89.0f);
-        m_pitch = 89.0f;
-    if (m_pitch < -89.0f)
-        m_pitch = -89.0f;
 
     m_front.x = sin(glm::radians(m_yaw)) * cos(glm::radians(m_pitch));
     m_front.y = sin(glm::radians(m_pitch));

src/gameplay/world.cpp

@@ -65,6 +65,7 @@ Player& World::get_player(const std::string& name) {
 }
 
 void World::init_world() {
+    m_cave_carcer.init(ChunkGenerator::seed());
     m_chunks.reserve(MAX_DISTANCE * MAX_DISTANCE * 4);
     auto t1 = std::chrono::system_clock::now();
 
@@ -113,6 +114,7 @@ void World::init_chunks() {
         }
     }
     for (auto& [pos, chunks] : m_chunks) {
+        m_cave_carcer.try_to_add_path(pos);
         chunks.gen_phase_one();
     }
     for (auto& [pos, chunks] : temp_neighbor) {
@@ -251,6 +253,8 @@ void World::init_chunks() {
     sync.store(1, std::memory_order_release);
     sync.load(std::memory_order_acquire);
 
+    m_cave_carcer.cleanup_finished_caves();
+
     std::vector<ChunkRenderData> pending_gen_data;
     pending_gen_data.reserve(m_chunks.size());
     for (auto& [pos, chunk] : m_chunks) {
@@ -355,6 +359,7 @@ void World::gen_chunks_internal() {
     // build new chunk, but the neighbor in m_chunks also need to re-build
 
     for (auto& [pos, chunk] : new_chunks) {
+        m_cave_carcer.try_to_add_path(pos);
         chunk.gen_phase_one();
     }
     for (auto& [pos, chunk] : temp_neighbor) {
@@ -500,6 +505,7 @@ void World::gen_chunks_internal() {
             m_new_chunk_queue.emplace_back(std::move(x));
         }
     }
+    m_cave_carcer.cleanup_finished_caves();
     m_chunk_gen_fraction = 1.0f;
 }
 
@@ -819,7 +825,7 @@ void World::rebuild_world() {
     }
     m_is_rebuilding = true;
     stop_gen_thread();
-
+    m_cave_carcer.reload(ChunkGenerator::seed());
     {
         std::scoped_lock lk(m_chunks_mutex, m_new_chunk_queue_mutex);
         m_chunks.clear();
@@ -841,4 +847,6 @@ void World::rendering_distance(int rendering_distance) {
     m_rendering_distance = rendering_distance;
 }
 
+CaveCarver& World::cave_carcer() { return m_cave_carcer; }
+
 } // namespace Cubed

src/tools/cubed_random.cpp

@@ -1,7 +1,5 @@
 #include "Cubed/tools/cubed_random.hpp"
 
-#include "Cubed/tools/log.hpp"
-
 namespace Cubed {
 
 Random::Random() {}
@@ -19,5 +17,13 @@ void Random::init(unsigned seed) {
     m_seed = seed;
     m_engine.seed(seed);
 }
+int Random::random_int(int min, int max) {
+    std::uniform_int_distribution<int> dist(min, max);
+    return dist(m_engine);
+}
+float Random::random_float(float min, float max) {
+    std::uniform_real_distribution<float> dist(min, max);
+    return dist(m_engine);
+}
 
 } // namespace Cubed

src/tools/math_tools.cpp

@@ -1,10 +1,11 @@
 #include "Cubed/tools/math_tools.hpp"
 
+#include <algorithm>
 #include <glm/gtc/type_ptr.hpp>
-
 namespace Cubed {
 
 namespace Math {
+
 void extract_frustum_planes(const glm::mat4& mvp_matrix,
                             std::vector<glm::vec4>& planes) {
     if (planes.size() != 6) {
@@ -37,6 +38,13 @@ void extract_frustum_planes(const glm::mat4& mvp_matrix,
     }
 }
 
+float smootherstep(float edge0, float edge1, float x) {
+
+    x = std::clamp((x - edge0) / (edge1 - edge0), 0.0f, 1.0f);
+
+    return x * x * x * (x * (6.0f * x - 15.0f) + 10.0f);
+}
+
 } // namespace Math
 
 } // namespace Cubed