add block particles property

src/graphics/render/Decorator.cpp

@@ -0,0 +1,103 @@
+#include "Decorator.hpp"
+
+#define GLM_ENABLE_EXPERIMENTAL
+#include <glm/gtx/norm.hpp>
+
+#include "ParticlesRenderer.hpp"
+#include "assets/assets_util.hpp"
+#include "content/Content.hpp"
+#include "voxels/Chunks.hpp"
+#include "voxels/Block.hpp"
+#include "world/Level.hpp"
+#include "window/Camera.hpp"
+
+/// @brief Not greather than 64 for this BIG_PRIME value
+inline constexpr int UPDATE_AREA_DIAMETER = 32;
+/// @brief Number of blocks in the volume
+inline constexpr int UPDATE_BLOCKS =
+    UPDATE_AREA_DIAMETER * UPDATE_AREA_DIAMETER * UPDATE_AREA_DIAMETER;
+/// @brief Number of update iterations
+inline constexpr int ITERATIONS = 512;
+/// @brief Big prime number used for pseudo-random 3d array iteration
+inline constexpr int BIG_PRIME = 666667;
+
+Decorator::Decorator(
+    const Level& level, ParticlesRenderer& particles, const Assets& assets
+)
+    : level(level), particles(particles), assets(assets) {
+}
+
+void Decorator::update(
+    float delta, const glm::ivec3& areaStart, const glm::ivec3& areaCenter
+) {
+    int index = currentIndex;
+    currentIndex = (currentIndex + BIG_PRIME) % UPDATE_BLOCKS;
+
+    const auto& chunks = *level.chunks;
+    const auto& indices = *level.content->getIndices();
+
+    int lx = index % UPDATE_AREA_DIAMETER;
+    int lz = (index / UPDATE_AREA_DIAMETER) % UPDATE_AREA_DIAMETER;
+    int ly = (index / UPDATE_AREA_DIAMETER / UPDATE_AREA_DIAMETER);
+    
+    auto pos = areaStart + glm::ivec3(lx, ly, lz);
+
+    if (auto vox = chunks.get(pos)) {
+        const auto& def = indices.blocks.require(vox->id);
+        if (def.particles) {
+            const auto& found = blockEmitters.find(pos);
+            if (found == blockEmitters.end()) {
+                auto treg = util::get_texture_region(
+                    assets, def.particles->texture, ""
+                );
+                blockEmitters[pos] = particles.add(std::make_unique<Emitter>(
+                    level,
+                    glm::vec3{pos.x + 0.5, pos.y + 0.5, pos.z + 0.5},
+                    *def.particles,
+                    treg.texture,
+                    treg.region,
+                    -1
+                ));
+            }
+        }
+    }
+}
+
+void Decorator::update(float delta, const Camera& camera) {
+    glm::ivec3 pos = camera.position;
+    pos -= glm::ivec3(UPDATE_AREA_DIAMETER / 2);
+    for (int i = 0; i < ITERATIONS; i++) {
+        update(delta, pos, camera.position);
+    }
+    const auto& chunks = *level.chunks;
+    const auto& indices = *level.content->getIndices();
+    auto iter = blockEmitters.begin();
+    while (iter != blockEmitters.end()) {
+        auto emitter = particles.getEmitter(iter->second);
+        if (emitter == nullptr) {
+            iter = blockEmitters.erase(iter);
+            continue;
+        }
+
+        bool remove = false;
+        if (auto vox = chunks.get(iter->first)) {
+            const auto& def = indices.blocks.require(vox->id);
+            if (def.particles == nullptr) {
+                remove = true;
+            }
+        } else {
+            iter = blockEmitters.erase(iter);
+            continue;
+        }
+        if (util::distance2(iter->first, glm::ivec3(camera.position)) >
+            UPDATE_AREA_DIAMETER * UPDATE_AREA_DIAMETER) {
+            remove = true;
+        }
+        if (remove) {
+            emitter->stop();
+            iter = blockEmitters.erase(iter);
+            continue;
+        }
+        iter++;
+    }
+}

src/graphics/render/Decorator.hpp

@@ -0,0 +1,31 @@
+#pragma once
+
+#include <glm/glm.hpp>
+#define GLM_ENABLE_EXPERIMENTAL
+#include <glm/gtx/hash.hpp>
+
+#include <unordered_map>
+
+class Level;
+class Chunks;
+class Camera;
+class Assets;
+class ParticlesRenderer;
+
+class Decorator {
+    const Level& level;
+    const Assets& assets;
+    ParticlesRenderer& particles;
+    std::unordered_map<glm::ivec3, uint64_t> blockEmitters;
+    int currentIndex = 0;
+
+    void update(
+        float delta, const glm::ivec3& areaStart, const glm::ivec3& areaCenter
+    );
+public:
+    Decorator(
+        const Level& level, ParticlesRenderer& particles, const Assets& assets
+    );
+
+    void update(float delta, const Camera& camera);
+};