refactor: meshes build queue instead of retrieveChunk

src/graphics/render/ChunksRenderer.cpp

@@ -11,8 +11,10 @@
 #include "world/Level.hpp"
 #include "window/Camera.hpp"
 #include "maths/FrustumCulling.hpp"
+#include "maths/util.hpp"
 #include "util/listutil.hpp"
 #include "util/ObjectsPool.hpp"
+#include "util/timeutil.hpp"
 #include "settings.hpp"
 #include "content/Content.hpp"
 
@@ -162,76 +164,63 @@ void ChunksRenderer::clear() {
     threadPool.clearQueue();
 }
 
-const ChunkMesh* ChunksRenderer::getOrRender(
-    const std::shared_ptr<Chunk>& chunk, bool important, bool lowPriority
-) {
-    auto found = meshes.find(glm::ivec2(chunk->x, chunk->z));
-    if (found == meshes.end()) {
-        return render(chunk, important, lowPriority);
-    }
-    if (chunk->flags.modified && chunk->flags.lighted) {
-        render(chunk, important, lowPriority);
-    }
-    return &found->second;
-}
-
 void ChunksRenderer::update() {
     threadPool.pullResults();
     enqueuedInFrame = 0;
-}
 
-const Mesh<ChunkVertex>* ChunksRenderer::retrieveChunk(
+    int width = chunks.getWidth();
-    size_t index, const Camera& camera, bool culling
+    int halfWidth = width / 2;
-) {
+    int halfHeight = chunks.getHeight() / 2;
-    auto chunk = chunks.getChunks()[index];
+    int centerX = chunks.getOffsetX() + halfWidth;
-    if (chunk == nullptr) {
+    int centerY = chunks.getOffsetY() + halfHeight;
-        return nullptr;
+
-    }
+    meshBuildQueue.clear();
-    if (!chunk->flags.lighted) {
+    auto& chunksArray = chunks.getChunks();
-        const auto& found = meshes.find({chunk->x, chunk->z});
+    for (int index = 0; index < chunks.getVolume(); index++) {
-        if (found == meshes.end()) {
+        const auto& chunk = chunks.getChunks()[index];
-            return nullptr;
+        if (chunk == nullptr || !chunk->flags.lighted) {
-        } else {
+            continue;
-            return found->second.mesh.get();
+        }
+        int x = chunk->x;
+        int z = chunk->z;
+        if (chunk->flags.modified || meshes.find({x, z}) == meshes.end()) {
+            meshBuildQueue.emplace_back(x - centerX, z - centerY);
         }
     }
-    float distance = glm::distance(
+    std::sort(
-        camera.position,
+        meshBuildQueue.begin(),
-        glm::vec3(
+        meshBuildQueue.end(),
-            (chunk->x + 0.5f) * CHUNK_W,
+        [](const glm::ivec2& a, const glm::ivec2& b) {
-            camera.position.y,
+            return util::length2(a) < util::length2(b);
-            (chunk->z + 0.5f) * CHUNK_D
+        }
-        )
     );
-    auto mesh = getOrRender(
-        chunk,
-        distance < CHUNK_W * 1.5f,
-        distance > CHUNK_W * settings.chunks.loadDistance.get() * 0.5
-    );
-    if (mesh == nullptr) {
-        return nullptr;
-    }
-    if (chunk->flags.dirtyHeights) {
-        chunk->updateHeights();
-    }
-    if (culling) {
-        const auto& meshAABB = mesh->meshAABB;
-        auto aabbMin = meshAABB.min();
-        auto aabbMax = meshAABB.max();
-        glm::vec3 min(
-            chunk->x * CHUNK_W + std::min(0.0f, aabbMin.x),
-            chunk->bottom,
-            chunk->z * CHUNK_D + std::min(0.0f, aabbMin.z)
-        );
-        glm::vec3 max(
-            chunk->x * CHUNK_W + aabbMax.x,
-            chunk->top,
-            chunk->z * CHUNK_D + aabbMax.z
-        );
 
-        if (!frustum.isBoxVisible(min, max)) return nullptr;
+    const int topN = 10;
+    int top = std::min<int>(meshBuildQueue.size(), topN);
+    for (int i = 0; i < top; i++) {
+        glm::ivec2 offset = meshBuildQueue[i];
+        size_t index =
+            (offset.y + halfHeight) * width + offset.x + halfWidth;
+
+        auto& chunk = chunksArray[index];
+        assert(chunk != nullptr);
+
+        float distance = glm::distance(
+            glm::vec3 (centerX, 0.0f, centerY),
+            glm::vec3(
+                (chunk->x + 0.5f) * CHUNK_W,
+                0,
+                (chunk->z + 0.5f) * CHUNK_D
+            )
+        );
+        bool important = distance < CHUNK_W * 1.5f;
+        bool lowPriority = distance > CHUNK_W * settings.chunks.loadDistance.get() * 0.5;
+
+        if (chunk->flags.dirtyHeights) {
+            chunk->updateHeights();
+        }
+        render(chunk, important, lowPriority);
     }
-    return mesh->mesh.get();
 }
 
 void ChunksRenderer::drawShadowsPass(
@@ -318,16 +307,43 @@ void ChunksRenderer::drawChunks(
     // TODO: minimize draw calls number
     for (int i = indices.size()-1; i >= 0; i--) {
         auto& chunk = chunks.getChunks()[indices[i].index];
-        auto mesh = retrieveChunk(indices[i].index, camera, culling);
+        if (chunk == nullptr) {
-        if (mesh == nullptr) {
             continue;
         }
+        auto found = meshes.find(glm::ivec2(chunk->x, chunk->z));
+        if (found == meshes.end()) {
+            continue;
+        }
+        auto& mesh = found->second;
+        if (mesh.mesh == nullptr) {
+            continue;
+        }
+        if (culling) {
+            const auto& meshAABB = mesh.meshAABB;
+            auto aabbMin = meshAABB.min();
+            auto aabbMax = meshAABB.max();
+            glm::vec3 min(
+                chunk->x * CHUNK_W + std::min(0.0f, aabbMin.x),
+                chunk->bottom,
+                chunk->z * CHUNK_D + std::min(0.0f, aabbMin.z)
+            );
+            glm::vec3 max(
+                chunk->x * CHUNK_W + aabbMax.x,
+                chunk->top,
+                chunk->z * CHUNK_D + aabbMax.z
+            );
+
+            if (!frustum.isBoxVisible(min, max)) {
+                continue;
+            }
+        }
+
         glm::vec3 coord(
             chunk->x * CHUNK_W + 0.5f, 0.5f, chunk->z * CHUNK_D + 0.5f
         );
         glm::mat4 model = glm::translate(glm::mat4(1.0f), coord);
         shader.uniformMatrix("u_model", model);
-        mesh->draw(GL_TRIANGLES, glm::distance2(camera.position * glm::vec3(1, 0, 1), 
+        mesh.mesh->draw(GL_TRIANGLES, glm::distance2(camera.position * glm::vec3(1, 0, 1), 
             (coord + glm::vec3(CHUNK_W * 0.5f, 0.0f, CHUNK_D * 0.5f))) < denseDistance2);
         visibleChunks++;
     }

src/graphics/render/ChunksRenderer.hpp

@@ -1,16 +1,17 @@
 #pragma once
 
+#define GLM_ENABLE_EXPERIMENTAL
+
+#include "util/ThreadPool.hpp"
+#include "commons.hpp"
+
 #include <memory>
 #include <vector>
 #include <unordered_map>
 
 #include <glm/glm.hpp>
-#define GLM_ENABLE_EXPERIMENTAL
 #include <glm/gtx/hash.hpp>
 
-#include "util/ThreadPool.hpp"
-#include "commons.hpp"
-
 template<typename VertexStructure> class Mesh;
 class Chunk;
 class Level;
@@ -44,22 +45,6 @@ struct RendererJob {
 };
 
 class ChunksRenderer {
-    const Chunks& chunks;
-    const Assets& assets;
-    const Frustum& frustum;
-    const EngineSettings& settings;
-
-    std::unique_ptr<BlocksRenderer> renderer;
-    std::unordered_map<glm::ivec2, ChunkMesh> meshes;
-    std::unordered_map<glm::ivec2, bool> inwork;
-    std::vector<ChunksSortEntry> indices;
-    util::ThreadPool<RendererJob, RendererResult> threadPool;
-    const Mesh<ChunkVertex>* retrieveChunk(
-        size_t index, const Camera& camera, bool culling
-    );
-    std::shared_ptr<VoxelsRenderVolume> prepareVoxelsVolume(const Chunk& chunk);
-
-    size_t enqueuedInFrame = 0;
 public:
     ChunksRenderer(
         const Level& level,
@@ -71,16 +56,9 @@ public:
     );
     virtual ~ChunksRenderer();
 
-    const ChunkMesh* render(
-        const std::shared_ptr<Chunk>& chunk, bool important, bool lowPriority
-    );
     void unload(const Chunk* chunk);
     void clear();
 
-    const ChunkMesh* getOrRender(
-        const std::shared_ptr<Chunk>& chunk, bool important, bool lowPriority
-    );
-
     void drawShadowsPass(
         const Camera& camera, Shader& shader, const Camera& playerCamera
     );
@@ -92,4 +70,25 @@ public:
     void update();
 
     static size_t visibleChunks;
+
+private:
+    const Chunks& chunks;
+    const Assets& assets;
+    const Frustum& frustum;
+    const EngineSettings& settings;
+
+    std::unique_ptr<BlocksRenderer> renderer;
+    std::unordered_map<glm::ivec2, ChunkMesh> meshes;
+    std::unordered_map<glm::ivec2, bool> inwork;
+    std::vector<ChunksSortEntry> indices;
+    util::ThreadPool<RendererJob, RendererResult> threadPool;
+    std::vector<glm::ivec2> meshBuildQueue;
+
+    size_t enqueuedInFrame = 0;
+
+    std::shared_ptr<VoxelsRenderVolume> prepareVoxelsVolume(const Chunk& chunk);
+
+    const ChunkMesh* render(
+        const std::shared_ptr<Chunk>& chunk, bool important, bool lowPriority
+    );
 };

src/maths/util.hpp

@@ -109,12 +109,16 @@ namespace util {
 
     /// @return integer square of vector length
     /// @note glm::length2 does not support integer vectors
-    inline int length2(const glm::ivec3& a) {
+    inline long long int length2(const glm::ivec2& a) {
+        return a.x * a.x + a.y * a.y;
+    }
+    
+    inline long long int length2(const glm::ivec3& a) {
         return a.x * a.x + a.y * a.y + a.z * a.z;
     }
 
     /// @return integer square of vector length
-    inline int length2(int x, int y, int z) {
+    inline long long int length2(int x, int y, int z) {
         return x * x + y * y + z * z;
     }