Skip to content

Commit

Permalink
Fix the check for continuous polygons
Browse files Browse the repository at this point in the history
  • Loading branch information
@e-n-f
e-n-f committed Oct 28, 2023
1 parent 23009c2 commit c2d6760
Show file tree
Hide file tree
Showing 5 changed files with 70 additions and 30 deletions.
60 changes: 38 additions & 22 deletions geometry.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1427,14 +1427,15 @@ drawvec checkerboard_anchors(drawvec const &geom, int tx, int ty, int z, unsigne
return out;
}

bool is_continous_poly(drawvec const &geom, size_t i, size_t j, int z, int tx, int ty, struct node *shared_nodes_map, size_t nodepos) {
bool is_continuous_ring(drawvec const &geom, size_t i, size_t j, int z, int tx, int ty, struct node *shared_nodes_map, size_t nodepos) {
size_t count = 0;

// j - 1 to avoid double-counting the duplicate last node
for (; i < j - 1; i++) {
if (is_shared_node(geom[i], z, tx, ty, shared_nodes_map, nodepos)) {
count++;

// every ring will have three shared nodes; the fourth indicates a shared vertex
if (count >= 4) {
return true;
}
Expand All @@ -1444,7 +1445,26 @@ bool is_continous_poly(drawvec const &geom, size_t i, size_t j, int z, int tx, i
return false;
}

drawvec buffer_poly(drawvec const &geom, double buffer, int z, int tx, int ty, struct node *shared_nodes_map, size_t nodepos) {
bool is_continuous_poly(drawvec const &geom, int z, int tx, int ty, struct node *shared_nodes_map, size_t nodepos) {
for (size_t i = 0; i < geom.size(); i++) {
if (geom[i].op == VT_MOVETO) {
size_t j;
for (j = i + 1; j < geom.size(); j++) {
if (geom[j].op != VT_LINETO) {
break;
}
}

if (is_continuous_ring(geom, i, j, z, tx, ty, shared_nodes_map, nodepos)) {
return true;
}
}
}

return false;
}

drawvec buffer_poly(drawvec const &geom, double buffer) {
drawvec out = geom;

if (buffer != 0) {
Expand All @@ -1457,32 +1477,28 @@ drawvec buffer_poly(drawvec const &geom, double buffer, int z, int tx, int ty, s
}
}

if (!is_continous_poly(geom, i, j, z, tx, ty, shared_nodes_map, nodepos)) {
for (size_t k = i; k < j - 1; k++) {
draw p0 = geom[(k + 0 - i) % (j - i - 1) + i];
draw p1 = geom[(k + 1 - i) % (j - i - 1) + i];
draw p2 = geom[(k + 2 - i) % (j - i - 1) + i];

double a10 = atan2(p1.y - p0.y, p1.x - p0.x);
double a21 = atan2(p2.y - p1.y, p2.x - p1.x);
for (size_t k = i; k < j - 1; k++) {
draw p0 = geom[(k + 0 - i) % (j - i - 1) + i];
draw p1 = geom[(k + 1 - i) % (j - i - 1) + i];
draw p2 = geom[(k + 2 - i) % (j - i - 1) + i];

double dx = cos(a10 - 90 * M_PI / 180) + cos(a21 - 90 * M_PI / 180);
double dy = sin(a10 - 90 * M_PI / 180) + sin(a21 - 90 * M_PI / 180);
double a10 = atan2(p1.y - p0.y, p1.x - p0.x);
double a21 = atan2(p2.y - p1.y, p2.x - p1.x);

// the angle halfway between the angles
// perpendicular to a0->a1 (a10) and a1->a2 (a21)
double a2 = atan2(dy, dx);
double dx = cos(a10 - 90 * M_PI / 180) + cos(a21 - 90 * M_PI / 180);
double dy = sin(a10 - 90 * M_PI / 180) + sin(a21 - 90 * M_PI / 180);

out[(k + 1 - i) % (j - i - 1) + i].x = std::round(p1.x + buffer * cos(a2));
out[(k + 1 - i) % (j - i - 1) + i].y = std::round(p1.y + buffer * sin(a2));
}
// the angle halfway between the angles
// perpendicular to a0->a1 (a10) and a1->a2 (a21)
double a2 = atan2(dy, dx);

out[j - 1].x = out[i].x;
out[j - 1].y = out[i].y;
} else {
printf("skipping continuous ring %zu to %zu\n", i, j);
out[(k + 1 - i) % (j - i - 1) + i].x = std::round(p1.x + buffer * cos(a2));
out[(k + 1 - i) % (j - i - 1) + i].y = std::round(p1.y + buffer * sin(a2));
}

out[j - 1].x = out[i].x;
out[j - 1].y = out[i].y;

i = j - 1;
}
}
Expand Down
3 changes: 2 additions & 1 deletion geometry.hpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -104,6 +104,7 @@ std::string overzoom(mvt_tile tile, int oz, int ox, int oy, int nz, int nx, int
std::string overzoom(std::string s, int oz, int ox, int oy, int nz, int nx, int ny,
int detail, int buffer, std::set<std::string> const &keep, bool do_compress);

drawvec buffer_poly(drawvec const &geom, double buffer, int z, int tx, int ty, struct node *shared_nodes_map, size_t nodepos);
drawvec buffer_poly(drawvec const &geom, double buffer);
bool is_continuous_poly(drawvec const &geom, int z, int tx, int ty, struct node *shared_nodes_map, size_t nodepos);

#endif
3 changes: 3 additions & 0 deletions serial.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -221,6 +221,7 @@ std::string serialize_feature(serial_feature *sf, long long wx, long long wy) {
serialize_int(s, sf->segment);

write_geometry(sf->geometry, s, wx, wy);
serialize_byte(s, sf->continuous);

if (sf->index != 0) {
serialize_ulong_long(s, sf->index);
Expand Down Expand Up @@ -276,8 +277,10 @@ serial_feature deserialize_feature(std::string &geoms, unsigned z, unsigned tx,
sf.index = 0;
sf.label_point = 0;
sf.extent = 0;
sf.continuous = -1; // unknown

sf.geometry = decode_geometry(&cp, z, tx, ty, sf.bbox, initial_x[sf.segment], initial_y[sf.segment]);
deserialize_byte(&cp, &sf.continuous);

if (sf.layer & (1 << FLAG_INDEX)) {
deserialize_ulong_long(&cp, &sf.index);
Expand Down
1 change: 1 addition & 0 deletions serial.hpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -43,6 +43,7 @@ struct serial_feature {

signed char t = 0;
signed char feature_minzoom = 0;
signed char continuous = -1; // is this a continuous polygon?

bool has_id = false;
unsigned long long id = 0;
Expand Down
33 changes: 26 additions & 7 deletions tile.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -331,7 +331,7 @@ struct ordercmp {
}
} ordercmp;

void rewrite(drawvec &geom, int z, int nextzoom, int maxzoom, long long *bbox, unsigned tx, unsigned ty, int buffer, int *within, std::atomic<long long> *geompos, compressor **geomfile, const char *fname, signed char t, int layer, signed char feature_minzoom, int child_shards, int max_zoom_increment, long long seq, int tippecanoe_minzoom, int tippecanoe_maxzoom, int segment, unsigned *initial_x, unsigned *initial_y, std::vector<long long> &metakeys, std::vector<long long> &metavals, bool has_id, unsigned long long id, unsigned long long index, unsigned long long label_point, long long extent) {
void rewrite(drawvec &geom, int z, int nextzoom, int maxzoom, long long *bbox, unsigned tx, unsigned ty, int buffer, int *within, std::atomic<long long> *geompos, compressor **geomfile, const char *fname, signed char t, int layer, signed char feature_minzoom, int child_shards, int max_zoom_increment, long long seq, int tippecanoe_minzoom, int tippecanoe_maxzoom, int segment, unsigned *initial_x, unsigned *initial_y, std::vector<long long> &metakeys, std::vector<long long> &metavals, bool has_id, unsigned long long id, unsigned long long index, unsigned long long label_point, long long extent, signed char continuous) {
if (geom.size() > 0 && (nextzoom <= maxzoom || additional[A_EXTEND_ZOOMS] || extend_zooms_max > 0)) {
int xo, yo;
int span = 1 << (nextzoom - z);
Expand Down Expand Up @@ -424,6 +424,7 @@ void rewrite(drawvec &geom, int z, int nextzoom, int maxzoom, long long *bbox, u
sf.label_point = label_point;
sf.extent = extent;
sf.feature_minzoom = feature_minzoom;
sf.continuous = continuous;

for (size_t i = 0; i < metakeys.size(); i++) {
sf.keys.push_back(metakeys[i]);
Expand Down Expand Up @@ -474,6 +475,7 @@ struct partial {
long long clustered = 0;
std::set<std::string> need_tilestats;
std::map<std::string, accum_state> attribute_accum_state;
int continuous;
};

struct partial_arg {
Expand Down Expand Up @@ -613,8 +615,8 @@ void *partial_feature_worker(void *v) {

drawvec geom = (*partials)[i].geoms[0];

if (additional[A_BUFFER_POLYGONS_OUTWARD] && t == VT_POLYGON) {
geom = buffer_poly(geom, (1LL << (32 - z - out_detail)) * sqrt(2), z, (*partials)[i].tx, (*partials)[i].ty, a->shared_nodes_map, a->nodepos);
if (additional[A_BUFFER_POLYGONS_OUTWARD] && t == VT_POLYGON && !((*partials)[i].continuous)) {
geom = buffer_poly(geom, (1LL << (32 - z - out_detail)) * sqrt(2));
}

to_tile_scale(geom, z, out_detail);
Expand Down Expand Up @@ -1461,7 +1463,7 @@ void remove_attributes(serial_feature &sf, std::set<std::string> const &exclude_
}
}

serial_feature next_feature(decompressor *geoms, std::atomic<long long> *geompos_in, int z, unsigned tx, unsigned ty, unsigned *initial_x, unsigned *initial_y, long long *original_features, long long *unclipped_features, int nextzoom, int maxzoom, int minzoom, int max_zoom_increment, size_t pass, std::atomic<long long> *along, long long alongminus, int buffer, int *within, compressor **geomfile, std::atomic<long long> *geompos, std::atomic<double> *oprogress, double todo, const char *fname, int child_shards, struct json_object *filter, const char *stringpool, long long *pool_off, std::vector<std::vector<std::string>> *layer_unmaps, bool first_time, bool compressed) {
serial_feature next_feature(decompressor *geoms, std::atomic<long long> *geompos_in, int z, unsigned tx, unsigned ty, unsigned *initial_x, unsigned *initial_y, long long *original_features, long long *unclipped_features, int nextzoom, int maxzoom, int minzoom, int max_zoom_increment, size_t pass, std::atomic<long long> *along, long long alongminus, int buffer, int *within, compressor **geomfile, std::atomic<long long> *geompos, std::atomic<double> *oprogress, double todo, const char *fname, int child_shards, struct json_object *filter, const char *stringpool, long long *pool_off, std::vector<std::vector<std::string>> *layer_unmaps, bool first_time, bool compressed, struct node *shared_nodes_map, size_t nodepos) {
while (1) {
serial_feature sf;
std::string s;
Expand Down Expand Up @@ -1512,9 +1514,21 @@ serial_feature next_feature(decompressor *geoms, std::atomic<long long> *geompos
(*unclipped_features)++;
}

if (sf.t == VT_POLYGON && sf.continuous < 0) {
// figure out whether the polygon is continuous the first time it is examined,
// since we don't have access to all of the shared nodes to determine this
// when the feature is first being ingested

if (prevent[P_SIMPLIFY_SHARED_NODES]) {
sf.continuous = is_continuous_poly(sf.geometry, z, tx, ty, shared_nodes_map, nodepos);
} else {
sf.continuous = false;
}
}

if (first_time && pass == 0) { /* only write out the next zoom once, even if we retry */
if (sf.tippecanoe_maxzoom == -1 || sf.tippecanoe_maxzoom >= nextzoom) {
rewrite(sf.geometry, z, nextzoom, maxzoom, sf.bbox, tx, ty, buffer, within, geompos, geomfile, fname, sf.t, sf.layer, sf.feature_minzoom, child_shards, max_zoom_increment, sf.seq, sf.tippecanoe_minzoom, sf.tippecanoe_maxzoom, sf.segment, initial_x, initial_y, sf.keys, sf.values, sf.has_id, sf.id, sf.index, sf.label_point, sf.extent);
rewrite(sf.geometry, z, nextzoom, maxzoom, sf.bbox, tx, ty, buffer, within, geompos, geomfile, fname, sf.t, sf.layer, sf.feature_minzoom, child_shards, max_zoom_increment, sf.seq, sf.tippecanoe_minzoom, sf.tippecanoe_maxzoom, sf.segment, initial_x, initial_y, sf.keys, sf.values, sf.has_id, sf.id, sf.index, sf.label_point, sf.extent, sf.continuous);
}
}

Expand Down Expand Up @@ -1646,14 +1660,16 @@ struct run_prefilter_args {
struct json_object *filter = NULL;
bool first_time = false;
bool compressed = false;
struct node *shared_nodes_map;
size_t nodepos;
};

void *run_prefilter(void *v) {
run_prefilter_args *rpa = (run_prefilter_args *) v;
json_writer state(rpa->prefilter_fp);

while (1) {
serial_feature sf = next_feature(rpa->geoms, rpa->geompos_in, rpa->z, rpa->tx, rpa->ty, rpa->initial_x, rpa->initial_y, rpa->original_features, rpa->unclipped_features, rpa->nextzoom, rpa->maxzoom, rpa->minzoom, rpa->max_zoom_increment, rpa->pass, rpa->along, rpa->alongminus, rpa->buffer, rpa->within, rpa->geomfile, rpa->geompos, rpa->oprogress, rpa->todo, rpa->fname, rpa->child_shards, rpa->filter, rpa->stringpool, rpa->pool_off, rpa->layer_unmaps, rpa->first_time, rpa->compressed);
serial_feature sf = next_feature(rpa->geoms, rpa->geompos_in, rpa->z, rpa->tx, rpa->ty, rpa->initial_x, rpa->initial_y, rpa->original_features, rpa->unclipped_features, rpa->nextzoom, rpa->maxzoom, rpa->minzoom, rpa->max_zoom_increment, rpa->pass, rpa->along, rpa->alongminus, rpa->buffer, rpa->within, rpa->geomfile, rpa->geompos, rpa->oprogress, rpa->todo, rpa->fname, rpa->child_shards, rpa->filter, rpa->stringpool, rpa->pool_off, rpa->layer_unmaps, rpa->first_time, rpa->compressed, rpa->shared_nodes_map, rpa->nodepos);
if (sf.t < 0) {
break;
}
Expand Down Expand Up @@ -2047,6 +2063,8 @@ long long write_tile(decompressor *geoms, std::atomic<long long> *geompos_in, ch
rpa.filter = filter;
rpa.first_time = first_time;
rpa.compressed = compressed_input;
rpa.shared_nodes_map = shared_nodes_map;
rpa.nodepos = nodepos;

if (pthread_create(&prefilter_writer, NULL, run_prefilter, &rpa) != 0) {
perror("pthread_create (prefilter writer)");
Expand All @@ -2066,7 +2084,7 @@ long long write_tile(decompressor *geoms, std::atomic<long long> *geompos_in, ch
ssize_t which_partial = -1;

if (prefilter == NULL) {
sf = next_feature(geoms, geompos_in, z, tx, ty, initial_x, initial_y, &original_features, &unclipped_features, nextzoom, maxzoom, minzoom, max_zoom_increment, pass, along, alongminus, buffer, within, geomfile, geompos, &oprogress, todo, fname, child_shards, filter, stringpool, pool_off, layer_unmaps, first_time, compressed_input);
sf = next_feature(geoms, geompos_in, z, tx, ty, initial_x, initial_y, &original_features, &unclipped_features, nextzoom, maxzoom, minzoom, max_zoom_increment, pass, along, alongminus, buffer, within, geomfile, geompos, &oprogress, todo, fname, child_shards, filter, stringpool, pool_off, layer_unmaps, first_time, compressed_input, shared_nodes_map, nodepos);
} else {
sf = parse_feature(prefilter_jp, z, tx, ty, layermaps, tiling_seg, layer_unmaps, postfilter != NULL);
}
Expand Down Expand Up @@ -2271,6 +2289,7 @@ long long write_tile(decompressor *geoms, std::atomic<long long> *geompos_in, ch
p.renamed = -1;
p.extent = sf.extent;
p.clustered = 0;
p.continuous = sf.continuous;

if (line_detail == detail && extra_detail >= 0 && z == maxzoom) {
p.extra_detail = extra_detail;
Expand Down

0 comments on commit c2d6760

Please sign in to comment.