Progress on adding filters to tippecanoe-overzoom

clip.cpp

@@ -754,7 +754,8 @@ static std::vector<std::pair<double, double>> clip_poly1(std::vector<std::pair<d
 
 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,
-		     std::vector<std::pair<unsigned, unsigned>> *next_overzoomed_tiles) {
+		     std::vector<std::pair<unsigned, unsigned>> *next_overzoomed_tiles,
+		     size_t multiplier, std::string const &filter) {
 	mvt_tile tile;
 
 	try {
@@ -768,12 +769,70 @@ std::string overzoom(std::string s, int oz, int ox, int oy, int nz, int nx, int
 		exit(EXIT_PROTOBUF);
 	}
 
-	return overzoom(tile, oz, ox, oy, nz, nx, ny, detail, buffer, keep, do_compress, next_overzoomed_tiles);
+	return overzoom(tile, oz, ox, oy, nz, nx, ny, detail, buffer, keep, do_compress, next_overzoomed_tiles, multiplier, filter);
+}
+
+struct tile_feature {
+	drawvec geom;
+	int t;
+	bool has_id;
+	unsigned long long id;
+	std::vector<unsigned> tags;
+	mvt_layer const *layer;
+
+	mvt_value value(std::string const &attr) const {
+		mvt_value v;
+		v.type = mvt_null;
+		return v;
+	}
+};
+
+struct sorter {
+	std::string attr;
+
+	sorter(std::string const attr_)
+	    : attr(attr_) {
+	}
+
+	bool operator()(const struct tile_feature &a, const struct tile_feature &b) {
+		mvt_value av = a.value(attr);
+		mvt_value bv = b.value(attr);
+
+		return av < bv;
+	}
+};
+
+void feature_out(tile_feature const &feature, mvt_layer &outlayer, std::set<std::string> const &keep) {
+	// Add geometry to output feature
+
+	mvt_feature outfeature;
+	outfeature.type = feature.t;
+	for (auto const &g : feature.geom) {
+		outfeature.geometry.emplace_back(g.op, g.x, g.y);
+	}
+
+	// ID and attributes, if it didn't get clipped away
+
+	if (outfeature.geometry.size() > 0) {
+		if (feature.has_id) {
+			outfeature.has_id = true;
+			outfeature.id = feature.id;
+		}
+
+		for (size_t i = 0; i + 1 < feature.tags.size(); i += 2) {
+			if (keep.size() == 0 || keep.find(feature.layer->keys[feature.tags[i]]) != keep.end()) {
+				outlayer.tag(outfeature, feature.layer->keys[feature.tags[i]], feature.layer->values[feature.tags[i + 1]]);
+			}
+		}
+
+		outlayer.features.push_back(outfeature);
+	}
 }
 
 std::string overzoom(mvt_tile tile, 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,
-		     std::vector<std::pair<unsigned, unsigned>> *next_overzoomed_tiles) {
+		     std::vector<std::pair<unsigned, unsigned>> *next_overzoomed_tiles,
+		     size_t multiplier, std::string const &filter) {
 	mvt_tile outtile;
 
 	for (auto const &layer : tile.layers) {
@@ -788,8 +847,9 @@ std::string overzoom(mvt_tile tile, int oz, int ox, int oy, int nz, int nx, int
 		outlayer.version = layer.version;
 		outlayer.extent = 1LL << det;
 
+		std::vector<tile_feature> tile_features;
+
 		for (auto const &feature : layer.features) {
-			mvt_feature outfeature;
 			drawvec geom;
 			int t = feature.type;
 
@@ -862,29 +922,27 @@ std::string overzoom(mvt_tile tile, int oz, int ox, int oy, int nz, int nx, int
 				geom = close_poly(geom);
 			}
 
-			// Add geometry to output feature
+			tile_feature tf;
+			tf.geom = geom;
+			tf.t = t;
+			tf.has_id = feature.has_id;
+			tf.id = feature.id;
+			tf.tags = feature.tags;
+			tf.layer = &layer;
 
-			outfeature.type = t;
+			tile_features.push_back(tf);
-			for (auto const &g : geom) {
+
-				outfeature.geometry.emplace_back(g.op, g.x, g.y);
+			if (tile_features.size() >= multiplier) {
+				std::sort(tile_features.begin(), tile_features.end(), sorter(filter));
+				feature_out(tile_features[0], outlayer, keep);
+				tile_features.clear();
 			}
+		}
 
-			// ID and attributes, if it didn't get clipped away
+		if (tile_features.size() > 0) {
-
+			std::sort(tile_features.begin(), tile_features.end(), sorter(filter));
-			if (outfeature.geometry.size() > 0) {
+			feature_out(tile_features[0], outlayer, keep);
-				if (feature.has_id) {
+			tile_features.clear();
-					outfeature.has_id = true;
-					outfeature.id = feature.id;
-				}
-
-				for (size_t i = 0; i + 1 < feature.tags.size(); i += 2) {
-					if (keep.size() == 0 || keep.find(layer.keys[feature.tags[i]]) != keep.end()) {
-						outlayer.tag(outfeature, layer.keys[feature.tags[i]], layer.values[feature.tags[i + 1]]);
-					}
-				}
-
-				outlayer.features.push_back(outfeature);
-			}
 		}
 
 		if (outlayer.features.size() > 0) {
@@ -905,7 +963,8 @@ std::string overzoom(mvt_tile tile, int oz, int ox, int oy, int nz, int nx, int
 				for (size_t y = 0; y < 2; y++) {
 					std::string child = overzoom(outtile, nz, nx, ny,
 								     nz + 1, nx * 2 + x, ny * 2 + y,
-								     detail, buffer, keep, false, NULL);
+								     detail, buffer, keep, false, NULL,
+								     multiplier, filter);
 					if (child.size() > 0) {
 						next_overzoomed_tiles->emplace_back(nx * 2 + x, ny * 2 + y);
 					}

geometry.hpp

@@ -100,10 +100,12 @@ double distance_from_line(long long point_x, long long point_y, long long segA_x
 
 std::string overzoom(mvt_tile tile, 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,
-		     std::vector<std::pair<unsigned, unsigned>> *next_overzoomed_tiles);
+		     std::vector<std::pair<unsigned, unsigned>> *next_overzoomed_tiles,
+		     size_t multiplier, std::string const &filter);
 
 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,
-		     std::vector<std::pair<unsigned, unsigned>> *next_overzoomed_tiles);
+		     std::vector<std::pair<unsigned, unsigned>> *next_overzoomed_tiles,
+		     size_t multiplier, std::string const &filter);
 
 #endif

overzoom.cpp

@@ -12,6 +12,8 @@ extern int optind;
 
 int detail = 12;  // tippecanoe-style: mvt extent == 1 << detail
 int buffer = 5;	  // tippecanoe-style: mvt buffer == extent * buffer / 256;
+int multiplier = 1;
+std::string filter;
 
 std::set<std::string> keep;
 
@@ -25,7 +27,7 @@ int main(int argc, char **argv) {
 	int i;
 	const char *outfile = NULL;
 
-	while ((i = getopt(argc, argv, "y:o:d:b:")) != -1) {
+	while ((i = getopt(argc, argv, "y:o:d:b:f:m:")) != -1) {
 		switch (i) {
 		case 'y':
 			keep.insert(optarg);
@@ -43,6 +45,14 @@ int main(int argc, char **argv) {
 			buffer = atoi(optarg);
 			break;
 
+		case 'm':
+			multiplier = atoi(optarg);
+			break;
+
+		case 'f':
+			filter = optarg;
+			break;
+
 		default:
 			usage(argv);
 		}
@@ -91,7 +101,7 @@ int main(int argc, char **argv) {
 		exit(EXIT_FAILURE);
 	}
 
-	std::string out = overzoom(tile, oz, ox, oy, nz, nx, ny, detail, buffer, keep, true, NULL);
+	std::string out = overzoom(tile, oz, ox, oy, nz, nx, ny, detail, buffer, keep, true, NULL, multiplier, filter);
 	fwrite(out.c_str(), sizeof(char), out.size(), f);
 	fclose(f);
 

tile-join.cpp

@@ -782,7 +782,7 @@ struct tileset_reader {
 		}
 
 		if (source.layers.size() != 0) {
-			std::string ret = overzoom(source, parent_tile.z, parent_tile.x, parent_tile.y, tile.z, tile.x, tile.y, -1, buffer, std::set<std::string>(), false, &next_overzoomed_tiles);
+			std::string ret = overzoom(source, parent_tile.z, parent_tile.x, parent_tile.y, tile.z, tile.x, tile.y, -1, buffer, std::set<std::string>(), false, &next_overzoomed_tiles, 1, "");
 			return ret;
 		}