Bail out sooner as the tile feature limit approaches

plugin.cpp

@@ -398,8 +398,6 @@ serial_feature parse_feature(json_pull *jp, int z, unsigned x, unsigned y, std::
 			sf.geometry = dv;
 			sf.seq = 0;
 			sf.index = 0;
-			sf.bbox[0] = sf.bbox[1] = LLONG_MAX;
-			sf.bbox[2] = sf.bbox[3] = LLONG_MIN;
 			sf.extent = 0;
 			sf.has_id = false;
 
@@ -434,23 +432,6 @@ serial_feature parse_feature(json_pull *jp, int z, unsigned x, unsigned y, std::
 				}
 			}
 
-			for (size_t i = 0; i < dv.size(); i++) {
-				if (dv[i].op == VT_MOVETO || dv[i].op == VT_LINETO) {
-					if (dv[i].x < sf.bbox[0]) {
-						sf.bbox[0] = dv[i].x;
-					}
-					if (dv[i].y < sf.bbox[1]) {
-						sf.bbox[1] = dv[i].y;
-					}
-					if (dv[i].x > sf.bbox[2]) {
-						sf.bbox[2] = dv[i].x;
-					}
-					if (dv[i].y > sf.bbox[3]) {
-						sf.bbox[3] = dv[i].y;
-					}
-				}
-			}
-
 			json_object *id = json_hash_get(j, "id");
 			if (id != NULL && id->type == JSON_NUMBER) {
 				sf.id = id->value.number.number;

serial.cpp

@@ -230,7 +230,7 @@ std::string serialize_feature(serial_feature *sf, long long wx, long long wy) {
 	return s;
 }
 
-serial_feature deserialize_feature(std::string const &geoms, unsigned z, unsigned tx, unsigned ty, unsigned *initial_x, unsigned *initial_y) {
+serial_feature deserialize_feature(std::string const &geoms, unsigned z, unsigned tx, unsigned ty, unsigned *initial_x, unsigned *initial_y, long long bbox[]) {
 	serial_feature sf;
 	const char *cp = geoms.c_str();
 
@@ -261,7 +261,7 @@ serial_feature deserialize_feature(std::string const &geoms, unsigned z, unsigne
 	sf.label_point = 0;
 	sf.extent = 0;
 
-	sf.geometry = decode_geometry(&cp, z, tx, ty, sf.bbox, initial_x[sf.segment], initial_y[sf.segment]);
+	sf.geometry = decode_geometry(&cp, z, tx, ty, bbox, initial_x[sf.segment], initial_y[sf.segment]);
 
 	if (sf.layer & (1 << FLAG_INDEX)) {
 		deserialize_ulong_long(&cp, &sf.index);
@@ -412,10 +412,11 @@ static void add_scaled_node(struct reader *r, serialization_state *sst, draw g)
 int serialize_feature(struct serialization_state *sst, serial_feature &sf, std::string const &layername) {
 	struct reader *r = &(*sst->readers)[sst->segment];
 
-	sf.bbox[0] = LLONG_MAX;
-	sf.bbox[1] = LLONG_MAX;
-	sf.bbox[2] = LLONG_MIN;
-	sf.bbox[3] = LLONG_MIN;
+	long long sf_bbox[4];
+	sf_bbox[0] = LLONG_MAX;
+	sf_bbox[1] = LLONG_MAX;
+	sf_bbox[2] = LLONG_MIN;
+	sf_bbox[3] = LLONG_MIN;
 
 	for (size_t i = 0; i < sf.geometry.size(); i++) {
 		if (sf.geometry[i].op == VT_MOVETO || sf.geometry[i].op == VT_LINETO) {
@@ -448,7 +449,7 @@ int serialize_feature(struct serialization_state *sst, serial_feature &sf, std::
 	// try to remind myself that the geometry in this function is in SCALED COORDINATES
 	drawvec scaled_geometry = sf.geometry;
 	sf.geometry.clear();
-	scale_geometry(sst, sf.bbox, scaled_geometry);
+	scale_geometry(sst, sf_bbox, scaled_geometry);
 
 	// This has to happen after scaling so that the wraparound detection has happened first.
 	// Otherwise the inner/outer calculation will be confused by bad geometries.
@@ -467,26 +468,26 @@ int serialize_feature(struct serialization_state *sst, serial_feature &sf, std::
 
 		scaled_geometry = remove_noop(scaled_geometry, sf.t, 0);
 
-		sf.bbox[0] = LLONG_MAX;
-		sf.bbox[1] = LLONG_MAX;
-		sf.bbox[2] = LLONG_MIN;
-		sf.bbox[3] = LLONG_MIN;
+		sf_bbox[0] = LLONG_MAX;
+		sf_bbox[1] = LLONG_MAX;
+		sf_bbox[2] = LLONG_MIN;
+		sf_bbox[3] = LLONG_MIN;
 
 		for (auto &g : scaled_geometry) {
 			long long x = SHIFT_LEFT(g.x);
 			long long y = SHIFT_LEFT(g.y);
 
-			if (x < sf.bbox[0]) {
-				sf.bbox[0] = x;
+			if (x < sf_bbox[0]) {
+				sf_bbox[0] = x;
 			}
-			if (y < sf.bbox[1]) {
-				sf.bbox[1] = y;
+			if (y < sf_bbox[1]) {
+				sf_bbox[1] = y;
 			}
-			if (x > sf.bbox[2]) {
-				sf.bbox[2] = x;
+			if (x > sf_bbox[2]) {
+				sf_bbox[2] = x;
 			}
-			if (y > sf.bbox[3]) {
-				sf.bbox[3] = y;
+			if (y > sf_bbox[3]) {
+				sf_bbox[3] = y;
 			}
 		}
 	}
@@ -672,8 +673,8 @@ int serialize_feature(struct serialization_state *sst, serial_feature &sf, std::
 
 	if (sf.t == VT_POINT) {
 		// keep old behavior, which loses one bit of precision at the bottom
-		midx = (sf.bbox[0] / 2 + sf.bbox[2] / 2) & ((1LL << 32) - 1);
-		midy = (sf.bbox[1] / 2 + sf.bbox[3] / 2) & ((1LL << 32) - 1);
+		midx = (sf_bbox[0] / 2 + sf_bbox[2] / 2) & ((1LL << 32) - 1);
+		midy = (sf_bbox[1] / 2 + sf_bbox[3] / 2) & ((1LL << 32) - 1);
 	} else {
 		// To reduce the chances of giving multiple polygons or linestrings
 		// the same index, use an arbitrary but predictable point from the
@@ -858,13 +859,13 @@ int serialize_feature(struct serialization_state *sst, serial_feature &sf, std::
 	fwrite_check(&index, sizeof(struct index), 1, r->indexfile, &r->indexpos, sst->fname);
 
 	for (size_t i = 0; i < 2; i++) {
-		if (sf.bbox[i] < r->file_bbox[i]) {
-			r->file_bbox[i] = sf.bbox[i];
+		if (sf_bbox[i] < r->file_bbox[i]) {
+			r->file_bbox[i] = sf_bbox[i];
 		}
 	}
 	for (size_t i = 2; i < 4; i++) {
-		if (sf.bbox[i] > r->file_bbox[i]) {
-			r->file_bbox[i] = sf.bbox[i];
+		if (sf_bbox[i] > r->file_bbox[i]) {
+			r->file_bbox[i] = sf_bbox[i];
 		}
 	}
 

serial.hpp

@@ -65,30 +65,30 @@ struct serial_feature {
 	int tippecanoe_minzoom = -1;
 	int tippecanoe_maxzoom = -1;
 
-	drawvec geometry = drawvec();
+	drawvec geometry;
 	unsigned long long index = 0;
 	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
+	// during initial serialization,
+	// and are used to store attributes that are altered during tiling
 
-	std::vector<std::string> full_keys{};
-	std::vector<serial_val> full_values{};
+	std::vector<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{};
+	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
@@ -99,28 +99,20 @@ struct serial_feature {
 	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;
+	bool reduced;				       // is polygon dust
+	bool coalesced;				       // was coalesced from multiple features
 	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
 	std::set<std::string> need_tilestats;
 	std::unordered_map<std::string, accum_state> attribute_accum_state;
-
-	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);
+serial_feature deserialize_feature(std::string const &geoms, unsigned z, unsigned tx, unsigned ty, unsigned *initial_x, unsigned *initial_y, long long bbox[]);
 
 struct reader {
 	int poolfd = -1;

tests/loop/out/-z0_-O200_--cluster-densest-as-needed.json

@@ -9,7 +9,7 @@
 "maxzoom": "0",
 "minzoom": "0",
 "name": "tests/loop/out/-z0_-O200_--cluster-densest-as-needed.json.check.mbtiles",
-"strategies": "[{\"coalesced_as_needed\":999,\"feature_count_desired\":1000}]",
+"strategies": "[{\"coalesced_as_needed\":999,\"feature_count_desired\":401}]",
 "type": "overlay",
 "version": "2"
 }, "features": [

tests/loop/out/-z0_-O200_--drop-densest-as-needed.json

@@ -9,7 +9,7 @@
 "maxzoom": "0",
 "minzoom": "0",
 "name": "tests/loop/out/-z0_-O200_--drop-densest-as-needed.json.check.mbtiles",
-"strategies": "[{\"dropped_as_needed\":999,\"feature_count_desired\":1000}]",
+"strategies": "[{\"dropped_as_needed\":999,\"feature_count_desired\":401}]",
 "type": "overlay",
 "version": "2"
 }, "features": [

tests/loop/out/-z0_-O200_--drop-fraction-as-needed.json

@@ -9,7 +9,7 @@
 "maxzoom": "0",
 "minzoom": "0",
 "name": "tests/loop/out/-z0_-O200_--drop-fraction-as-needed.json.check.mbtiles",
-"strategies": "[{\"dropped_as_needed\":999,\"feature_count_desired\":1000}]",
+"strategies": "[{\"dropped_as_needed\":999,\"feature_count_desired\":401}]",
 "type": "overlay",
 "version": "2"
 }, "features": [