1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2023 Geofabrik GmbH
* Copyright (C) 2025 Artem Pavlenko
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*****************************************************************************/
#ifndef MAPNIK_MBTILES_SOURCE_HPP
#define MAPNIK_MBTILES_SOURCE_HPP
#include <mapnik/global.hpp>
#include "tiles_source.hpp"
#include "sqlite_connection.hpp"
// mapnik_vector_tile
#include "vector_tile_compression.hpp"
// boost
#include <boost/format.hpp>
namespace mapnik {
class mbtiles_source : public tiles_source
{
private:
std::uint8_t minzoom_ = 1;
std::uint8_t maxzoom_ = 14;
mapnik::box2d<double> extent_;
std::string database_path_;
std::shared_ptr<sqlite_connection> dataset_;
std::string format_;
inline std::uint8_t zoom_from_string(std::string const& str) { return std::stoi(str); }
std::int32_t convert_y(std::int32_t y, std::uint8_t zoom) const { return (1 << zoom) - 1 - y; }
public:
mbtiles_source(std::string const& database_path)
: database_path_(database_path)
{
int sqlite_mode = SQLITE_OPEN_READONLY | SQLITE_OPEN_NOMUTEX | SQLITE_OPEN_SHAREDCACHE;
dataset_ = std::make_shared<sqlite_connection>(database_path_, sqlite_mode);
auto result = dataset_->execute_query("SELECT value FROM metadata WHERE name = 'format';");
if (!result->is_valid() || !result->step_next() || result->column_type(0) != SQLITE_TEXT)
{
throw mapnik::datasource_exception("MBTiles Plugin: Can't infer tile format value from " + database_path_);
}
format_ = result->column_text(0);
if (format_ != "pbf" && format_ != "jpg" && format_ != "png" && format_ != "webp" && format_ != "avif")
{
throw mapnik::datasource_exception("MBTiles Plugin: " + database_path_ + " has unsupported tile format '" +
format_ + "', expected 'pbf|jpg|png|webp|avif'.");
}
result = dataset_->execute_query("SELECT value FROM metadata WHERE name = 'bounds';");
if (result->is_valid() && result->step_next() && result->column_type(0) == SQLITE_TEXT)
{
std::string const extent_str = result->column_text(0);
if (extent_str.empty())
{
throw mapnik::datasource_exception("MBTiles Plugin: " + database_path_ + " has invalid extent.");
}
extent_.from_string(extent_str);
}
if (!extent_.valid())
{
throw mapnik::datasource_exception("MBTiles Plugin: " + database_path_ + " extent is invalid.");
}
result = dataset_->execute_query("SELECT value FROM metadata WHERE name = 'minzoom';");
if (result->is_valid() && result->step_next() && result->column_type(0) == SQLITE_TEXT)
{
minzoom_ = zoom_from_string(result->column_text(0));
}
// initialize maxzoom
result = dataset_->execute_query("SELECT value FROM metadata WHERE name = 'maxzoom';");
if (result->is_valid() && result->step_next() && result->column_type(0) == SQLITE_TEXT)
{
maxzoom_ = zoom_from_string(result->column_text(0));
}
}
std::uint8_t minzoom() const { return minzoom_; }
std::uint8_t maxzoom() const { return maxzoom_; }
mapnik::box2d<double> const& extent() const { return extent_; }
std::string get_tile(std::uint8_t z, std::uint32_t x, std::uint32_t y) const
{
std::string sql =
(boost::format(
"SELECT tile_data FROM tiles WHERE zoom_level = %1% AND tile_column = %2% AND tile_row = %3%") %
(int)z % x % convert_y(y, z))
.str();
auto result = dataset_->execute_query(sql);
int size = 0;
char const* blob = nullptr;
if (result->is_valid() && result->step_next() && result->column_type(0) == SQLITE_BLOB)
{
blob = result->column_blob(0, size);
}
else
{
return std::string();
}
if (mapnik::vector_tile_impl::is_gzip_compressed(blob, size) ||
mapnik::vector_tile_impl::is_zlib_compressed(blob, size))
{
std::string decompressed;
mapnik::vector_tile_impl::zlib_decompress(blob, size, decompressed);
return decompressed;
}
return std::string(blob, size);
}
std::string get_tile_raw(std::uint8_t z, std::uint32_t x, std::uint32_t y) const
{
std::string sql =
(boost::format(
"SELECT tile_data FROM tiles WHERE zoom_level = %1% AND tile_column = %2% AND tile_row = %3%") %
(int)z % x % convert_y(y, z))
.str();
auto result = dataset_->execute_query(sql);
int size = 0;
char const* blob = nullptr;
if (result->is_valid() && result->step_next() && result->column_type(0) == SQLITE_BLOB)
{
blob = result->column_blob(0, size);
}
else
{
return std::string();
}
return std::string(blob, size);
}
boost::json::value metadata() const
{
std::string metadata;
boost::json::value json_value;
if (!is_raster())
{
auto result = dataset_->execute_query("SELECT value FROM metadata WHERE name = 'json';");
if (result->is_valid() && result->step_next() && result->column_type(0) == SQLITE_TEXT)
{
metadata = result->column_text(0);
}
if (metadata.empty())
{
throw mapnik::datasource_exception("Tiles plugin: " + database_path_ +
" has no 'json' entry in metadata table.");
}
try
{
json_value = boost::json::parse(metadata);
}
catch (std::exception const& ex)
{
std::cerr << ex.what() << std::endl;
}
}
return json_value;
}
bool is_raster() const { return format_ == "png" || format_ == "jpg" || format_ == "webp" || format_ == "avif"; }
};
} // namespace mapnik
#endif // MAPNIK_MBTILES_SOURCE_HPP
|
