Merge pull request #177 from konstructs/feature-handle-new-chunk-updates

Handle server updates more intelligently

Author: petterarvidsson

src/chunk_shader.cpp

@@ -167,8 +167,9 @@ namespace konstructs {
                             Vector3i pos(p, q, k);
                             int distance = (pos - player_chunk).norm();
                             int score;
+                            auto it = models.find(pos);
+                            bool is_updated = world.chunk_updated_since_requested(pos);
                             if(chunk_visible(planes, pos)) {
-                                auto it = models.find(pos);
                                 if(it != models.end()) {
                                     /* Ok, found the model, let's render it!
                                      */
@@ -177,10 +178,18 @@ namespace konstructs {
                                     c.set(translation, m->translation);
                                     c.draw(m);
                                     faces += m->faces;
-                                    /* We already have a model of the chunk,
-                                     * so we really don't need it.
-                                     */
-                                    score = NO_CHUNK_FOUND;
+                                    if(is_updated) {
+                                        /* We already have a model of the chunk,
+                                         * but it's outdated, so it needs to be refreshed.
+                                         */
+                                        score = distance / 2;
+                                    } else {
+                                        /* We already have a model of the chunk,
+                                         * it didn't change since last requested,
+                                         * so we really don't need it.
+                                         */
+                                        score = NO_CHUNK_FOUND;
+                                    }
                                 } else {
                                     /* We wanted to render the model,
                                      * but we didn't have it, so we really want this chunk!
@@ -192,7 +201,13 @@ namespace konstructs {
                                  * but if she turns around she might need this chunk
                                  * so let's fetch it, but not super urgent
                                  */
-                                score = distance;
+                                if(it != models.end() && !is_updated) {
+                                    /* We already have it and it's not updated */
+                                    score = NO_CHUNK_FOUND;
+                                } else {
+                                    /* We don't have it or it's update*/
+                                    score = distance;
+                                }
                             }
                             if(score < best_chunk_score && world.chunk_not_requested(pos)) {
                                 best_chunk_score = score;

src/main.cpp

@@ -366,6 +366,9 @@ class Konstructs: public nanogui::Screen {
         case 'T':
             handle_time(packet->to_string());
             break;
+        case 'c':
+            handle_chunk_updated(packet->to_string());
+            break;
         default:
             cout << "UNKNOWN: " << packet->type << endl;
             break;
@@ -506,6 +509,15 @@ class Konstructs: public nanogui::Screen {
         glfwSetTime((double)time_value);
     }
 
+    void handle_chunk_updated(const string &str) {
+        int p,q,k;
+        if(sscanf(str.c_str(), ",%d,%d,%d", &p, &q, &k) != 3) {
+            throw std::runtime_error(str);
+        }
+        Vector3i pos(p, q, k);
+        world.set_chunk_updated(pos);
+    }
+
     float time_of_day() {
         if (day_length <= 0) {
             return 0.5;

src/world.cpp

@@ -4,11 +4,22 @@ namespace konstructs {
     void World::request_chunk(const Vector3i &pos, Client &client) {
         /* Keep track of the chunk so we don't request it again */
         requested.insert(pos);
+        /* Remove requested chunks from updated (we will get the latest update) */
+        updated.erase(pos);
         client.chunk(pos);
     }
 
+    void World::set_chunk_updated(const Vector3i &pos) {
+        updated.insert(pos);
+    }
+
     bool World::chunk_not_requested(const Vector3i &pos) const {
-        return requested.find(pos) == requested.end() && chunks.find(pos) == chunks.end();
+        return (updated.find(pos) != updated.end() && chunks.find(pos) != chunks.end()) // Updated and exist in the world
+            || (requested.find(pos) == requested.end() && chunks.find(pos) == chunks.end()); // Not requested and not in world
+    }
+
+    bool World::chunk_updated_since_requested(const Vector3i &pos) const {
+        return updated.find(pos) != updated.end();
     }
 
     void World::delete_unused_chunks(const Vector3f position, const int radi) {

src/world.h

@@ -12,8 +12,10 @@ namespace konstructs {
     class World {
     public:
         void request_chunk(const Vector3i &pos, Client &client);
+        void set_chunk_updated(const Vector3i &pos);
         bool chunk_not_requested(const Vector3i &pos) const;
-void delete_unused_chunks(const Vector3f position, const int radi);
+        bool chunk_updated_since_requested(const Vector3i &pos) const;
+        void delete_unused_chunks(const Vector3f position, const int radi);
         void insert(std::shared_ptr<ChunkData> data);
         const std::shared_ptr<ChunkData> chunk_at(const Vector3i &block_pos) const;
         const std::shared_ptr<ChunkData> chunk(const Vector3i &chunk_pos) const;
@@ -23,6 +25,7 @@ void delete_unused_chunks(const Vector3f position, const int radi);
     private:
         std::unordered_map<Vector3i, std::shared_ptr<ChunkData>, matrix_hash<Vector3i>> chunks;
         std::unordered_set<Vector3i, matrix_hash<Vector3i>> requested;
+        std::unordered_set<Vector3i, matrix_hash<Vector3i>> updated;
     };
 };