Files
tippecanoe/serial.hpp
T
Claude d3a98170bf Look up shared nodes once per vertex instead of once per tile
With --no-simplification-of-shared-nodes, simplify_lines() used to offset
every vertex of every feature to world coordinates and check it against
the Bloom filter and the global sorted list of shared nodes, in every
tile at every zoom level.

Whether a vertex is a shared node depends only on its world coordinates,
so now it is found once, after the list of shared nodes has been made
and before the geometry is sorted, by a parallel pass over each reader's
geometry that marks each vertex in place, in the upper bits of its
serialized operation byte. Decoding puts that state into a new field of
draw (which still fits in 16 bytes), and it is carried through clipping,
the copies across the antimeridian at z0, and the geometry written for
the next zoom level. Polygon cleaning of coalesced features restores the
state of any output vertex with the same coordinates as an input vertex.

Vertices whose state is still unknown, because they were created by
clipping or polygon cleaning or came back from a prefilter, are still
looked up in the global list when they are simplified, so the output is
unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01P2nBqZisxNQfmEmon3vE9v
2026-09-23 17:39:48 +00:00

330 lines
9.2 KiB
C++

#ifndef SERIAL_HPP
#define SERIAL_HPP
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <vector>
#include <atomic>
#include <memory>
#include <sys/stat.h>
#include "geometry.hpp"
#include "mbtiles.hpp"
#include "jsonpull/jsonpull.h"
size_t fwrite_check(const void *ptr, size_t size, size_t nitems, FILE *stream, std::atomic<long long> *fpos, const char *fname);
void serialize_int(FILE *out, int n, std::atomic<long long> *fpos, const char *fname);
void serialize_long_long(FILE *out, long long n, std::atomic<long long> *fpos, const char *fname);
void serialize_ulong_long(FILE *out, unsigned long long n, std::atomic<long long> *fpos, const char *fname);
void serialize_byte(FILE *out, signed char n, std::atomic<long long> *fpos, const char *fname);
void serialize_uint(FILE *out, unsigned n, std::atomic<long long> *fpos, const char *fname);
void serialize_int(std::string &out, int n);
void serialize_long_long(std::string &out, long long n);
void serialize_ulong_long(std::string &out, unsigned long long n);
void serialize_byte(std::string &out, signed char n);
void serialize_uint(std::string &out, unsigned n);
void deserialize_int(const char **f, int *n);
void deserialize_long_long(const char **f, long long *n);
void deserialize_ulong_long(const char **f, unsigned long long *n);
void deserialize_uint(const char **f, unsigned *n);
void deserialize_byte(const char **f, signed char *n);
// This is the main representation of attribute values in memory and
// in the string pool. The type is one of the mvt_value type (mvt_string,
// mvt_double, mvt_bool, or mvt_null). Note that all numeric values,
// whether integer or floating point, use mvt_double here.
struct serial_val {
int type;
std::string s;
bool operator<(const serial_val &o) const;
bool operator!=(const serial_val &o) const;
serial_val() {
type = 0;
}
serial_val(int t, const std::string &val)
: type(t), s(val) {
}
// These functions for interface compatibility with mvt_value:
serial_val(double val) {
type = mvt_double;
s = milo::dtoa_milo(val);
}
double to_double() const {
return atof(s.c_str());
}
std::string get_string_value() const {
return s;
}
void set_string_value(std::string const &val) {
type = mvt_string;
s = val;
}
size_t get_count() const {
size_t found = s.find('\0');
if (found == std::string::npos) {
return 0;
} else {
return atoll(s.c_str() + found + 1);
}
}
void set_double_count(double v, size_t c) {
type = mvt_double;
s = milo::dtoa_milo(v) + '\0' + std::to_string(c);
}
};
struct key_pool {
std::unordered_map<std::string, std::shared_ptr<std::string>> mapping;
std::shared_ptr<std::string> pool(std::string const &s) {
auto f = mapping.find(s);
if (f != mapping.end()) {
return f->second;
}
std::shared_ptr<std::string> p = std::make_shared<std::string>();
*p = s;
mapping.emplace(s, p);
return p;
}
};
struct serial_feature {
long long layer = 0;
int segment = 0;
long long seq = 0;
signed char t = 0;
signed char feature_minzoom = 0;
bool has_id = false;
unsigned long long id = 0;
int tippecanoe_minzoom = -1;
int tippecanoe_maxzoom = -1;
drawvec geometry = drawvec();
unsigned long long index = 0;
unsigned long long gap = 0; // filled in during z0. square of planar distance
unsigned long long label_point = 0;
long long extent = 0;
// These fields are not directly serialized, but are used
// to create the keys and values references into the string pool
// during initial serialization
std::vector<std::shared_ptr<std::string>> full_keys{};
std::vector<serial_val> full_values{};
// These fields are generated from full_keys and full_values
// during initial serialization and then replace the string
// representations:
std::vector<long long> keys{};
std::vector<long long> values{};
// These fields are used during tiling,
// but are not serialized and are not expected
// to be provided by frontends:
long long bbox[4] = {0, 0, 0, 0};
drawvec edge_nodes; // what nodes at the tile edge were added during clipping?
#define FEATURE_DROPPED -1
#define FEATURE_KEPT 0
#define FEATURE_ADDED_FOR_MULTIPLIER_DENSITY INT_MAX
// <0: dropped
// 0: kept
// >0: sequence number of additional feature kept by retain-points-multiplier
// INT_MAX: additional feature kept by preserve-multiplier-density-threshold
int dropped = FEATURE_DROPPED; // was this feature dropped by rate?
// unsigned long long drop_by; // dot-dropping priority
bool reduced; // is polygon dust
bool coalesced; // was coalesced from multiple features
int line_detail; // current tile resolution being used for simplification
int extra_detail; // extra tile resolution to retain in output
int maxzoom;
double spacing; // feature spacing for --calculate-feature-density
double simplification; // simplification level at this zoom level
std::vector<ssize_t> arc_polygon; // used in --detect-shared-borders
ssize_t renamed; // used in --detect-shared-borders logic
long long clustered; // does this feature need the clustered/point_count attributes?
const char *stringpool; // string pool for keys/values lookup
std::shared_ptr<std::string> tile_stringpool; // string pool for mvt_value construction
int z; // tile being produced
int tx;
int ty;
};
std::string serialize_feature(serial_feature *sf, long long wx, long long wy);
serial_feature deserialize_feature(std::string const &geoms, unsigned z, unsigned tx, unsigned ty, unsigned *initial_x, unsigned *initial_y);
struct reader {
int poolfd = -1;
int treefd = -1;
int geomfd = -1;
int indexfd = -1;
int vertexfd = -1;
int nodefd = -1;
struct memfile *poolfile = NULL;
struct memfile *treefile = NULL;
FILE *geomfile = NULL;
FILE *indexfile = NULL;
FILE *vertexfile = NULL;
FILE *nodefile = NULL;
std::atomic<long long> geompos;
std::atomic<long long> indexpos;
std::atomic<long long> vertexpos;
std::atomic<long long> nodepos;
long long file_bbox[4] = {0, 0, 0, 0};
long long file_bbox1[4] = {0xFFFFFFFF, 0xFFFFFFFF, 0, 0}; // standard -180 to 180 world plane
long long file_bbox2[4] = {0x1FFFFFFFF, 0xFFFFFFFF, 0x100000000, 0}; // 0 to 360 world plane
struct stat geomst {};
char *geom_map = NULL;
std::vector<ssize_t> key_dedup = std::vector<ssize_t>(655536, -1);
std::vector<ssize_t> value_dedup = std::vector<ssize_t>(655536, -1);
reader()
: geompos(0), indexpos(0), vertexpos(0), nodepos(0) {
}
reader(reader const &r) {
poolfd = r.poolfd;
treefd = r.treefd;
geomfd = r.geomfd;
indexfd = r.indexfd;
vertexfd = r.vertexfd;
nodefd = r.nodefd;
poolfile = r.poolfile;
treefile = r.treefile;
geomfile = r.geomfile;
indexfile = r.indexfile;
vertexfile = r.vertexfile;
nodefile = r.nodefile;
long long p = r.geompos;
geompos = p;
p = r.indexpos;
indexpos = p;
p = r.vertexpos;
vertexpos = p;
p = r.nodepos;
nodepos = p;
memcpy(file_bbox, r.file_bbox, sizeof(file_bbox));
geomst = r.geomst;
geom_map = r.geom_map;
}
};
struct serialization_state {
const char *fname = NULL; // source file name
int line = 0; // user-oriented location within source for error reports
std::atomic<long long> *layer_seq = NULL; // sequence within current layer
std::atomic<long long> *progress_seq = NULL; // overall sequence for progress indicator
std::vector<struct reader> *readers = NULL; // array of data for each input thread
int segment = 0; // the current input thread
unsigned *initial_x = NULL; // relative offset of all geometries
unsigned *initial_y = NULL;
int *initialized = NULL;
double *dist_sum = NULL; // running tally for calculation of resolution within features
size_t *dist_count = NULL;
double *area_sum = NULL;
bool want_dist = false;
int maxzoom = 0;
int basezoom = 0;
bool filters = false;
bool uses_gamma = false;
std::map<std::string, layermap_entry> *layermap = NULL;
std::unordered_map<std::string, int> const *attribute_types = NULL;
std::set<std::string> *exclude = NULL;
std::set<std::string> *include = NULL;
int exclude_all = 0;
};
struct vertex {
// these are scaled geometry,
// but because scaling is disabled if P_SHARED_NODES is set,
// they are effectively also world coordinates
draw p1;
draw mid;
draw p2;
vertex(draw one, draw joint, draw two) {
if (one < two) {
p1 = one;
p2 = two;
} else {
p1 = two;
p2 = one;
}
mid = joint;
}
bool operator<(const vertex &v) const {
if (mid < v.mid) {
return true;
} else if (mid == v.mid) {
if (p1 < v.p1) {
return true;
} else if (p1 == v.p1) {
if (p2 < v.p2) {
return true;
}
}
}
return false;
}
};
struct node {
// this is in quadkey coordinates so that the nodes for each tile
// will be adjacent in memory, reducing potential thrashing during
// the binary search.
unsigned long long index;
};
int nodecmp(const void *void1, const void *void2);
void mark_shared_nodes(char *feature, size_t len, unsigned *initial_x, unsigned *initial_y, struct node const *shared_nodes_map, size_t nodepos, std::string const &shared_nodes_bloom);
int serialize_feature(struct serialization_state *sst, serial_feature &sf, std::string const &layername);
void coerce_value(std::string const &key, int &vt, std::string &val, std::unordered_map<std::string, int> const *attribute_types);
#endif