1 /*
2 Minetest
3 Copyright (C) 2013, 2017 celeron55, Perttu Ahola <celeron55@gmail.com>
4 
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU Lesser General Public License as published by
7 the Free Software Foundation; either version 2.1 of the License, or
8 (at your option) any later version.
9 
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 GNU Lesser General Public License for more details.
14 
15 You should have received a copy of the GNU Lesser General Public License along
16 with this program; if not, write to the Free Software Foundation, Inc.,
17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 */
19 
20 #pragma once
21 
22 #include <ctime>
23 #include <mutex>
24 #include "mapblock_mesh.h"
25 #include "threading/mutex_auto_lock.h"
26 #include "util/thread.h"
27 
28 struct CachedMapBlockData
29 {
30 	v3s16 p = v3s16(-1337, -1337, -1337);
31 	MapNode *data = nullptr; // A copy of the MapBlock's data member
32 	int refcount_from_queue = 0;
33 	std::time_t last_used_timestamp = std::time(0);
34 
35 	CachedMapBlockData() = default;
36 	~CachedMapBlockData();
37 };
38 
39 struct QueuedMeshUpdate
40 {
41 	v3s16 p = v3s16(-1337, -1337, -1337);
42 	bool ack_block_to_server = false;
43 	int crack_level = -1;
44 	v3s16 crack_pos;
45 	MeshMakeData *data = nullptr; // This is generated in MeshUpdateQueue::pop()
46 
47 	QueuedMeshUpdate() = default;
48 	~QueuedMeshUpdate();
49 };
50 
51 /*
52 	A thread-safe queue of mesh update tasks and a cache of MapBlock data
53 */
54 class MeshUpdateQueue
55 {
56 	enum UpdateMode
57 	{
58 		FORCE_UPDATE,
59 		SKIP_UPDATE_IF_ALREADY_CACHED,
60 	};
61 
62 public:
63 	MeshUpdateQueue(Client *client);
64 
65 	~MeshUpdateQueue();
66 
67 	// Caches the block at p and its neighbors (if needed) and queues a mesh
68 	// update for the block at p
69 	void addBlock(Map *map, v3s16 p, bool ack_block_to_server, bool urgent);
70 
71 	// Returned pointer must be deleted
72 	// Returns NULL if queue is empty
73 	QueuedMeshUpdate *pop();
74 
size()75 	u32 size()
76 	{
77 		MutexAutoLock lock(m_mutex);
78 		return m_queue.size();
79 	}
80 
81 private:
82 	Client *m_client;
83 	std::vector<QueuedMeshUpdate *> m_queue;
84 	std::set<v3s16> m_urgents;
85 	std::map<v3s16, CachedMapBlockData *> m_cache;
86 	std::mutex m_mutex;
87 
88 	// TODO: Add callback to update these when g_settings changes
89 	bool m_cache_enable_shaders;
90 	bool m_cache_smooth_lighting;
91 	int m_meshgen_block_cache_size;
92 
93 	CachedMapBlockData *cacheBlock(Map *map, v3s16 p, UpdateMode mode,
94 			size_t *cache_hit_counter = NULL);
95 	CachedMapBlockData *getCachedBlock(const v3s16 &p);
96 	void fillDataFromMapBlockCache(QueuedMeshUpdate *q);
97 	void cleanupCache();
98 };
99 
100 struct MeshUpdateResult
101 {
102 	v3s16 p = v3s16(-1338, -1338, -1338);
103 	MapBlockMesh *mesh = nullptr;
104 	bool ack_block_to_server = false;
105 
106 	MeshUpdateResult() = default;
107 };
108 
109 class MeshUpdateThread : public UpdateThread
110 {
111 public:
112 	MeshUpdateThread(Client *client);
113 
114 	// Caches the block at p and its neighbors (if needed) and queues a mesh
115 	// update for the block at p
116 	void updateBlock(Map *map, v3s16 p, bool ack_block_to_server, bool urgent);
117 
118 	v3s16 m_camera_offset;
119 	MutexedQueue<MeshUpdateResult> m_queue_out;
120 
121 private:
122 	MeshUpdateQueue m_queue_in;
123 
124 	// TODO: Add callback to update these when g_settings changes
125 	int m_generation_interval;
126 
127 protected:
128 	virtual void doUpdate();
129 };
130