MapLibre Tile support pulls in the maplibre-tile-spec submodule and needs
cmake to build it, which is a lot to ask of anyone who only wants to work
with Mapbox Vector Tiles.
`make MLT=0` compiles with -DNO_MLT, skips the submodule and its cmake
build entirely, and drops the MLT tests from `make test`. The result needs
no dependencies beyond the ones MVT already needed, and can be built from
a checkout with no submodules at all.
Everything that touches the MLT library is behind the #ifdef, which is
just the two files that were written for it. The option parsing and the
tile format helpers stay compiled either way, so nothing else needs to
know: --output-format=mlt reports that the build has no MLT support rather
than being an unrecognized value, and a tile that is recognized as MLT
reports the same instead of being misparsed as a protobuf, since the
format sniffing itself doesn't need the library.
CI builds and tests this configuration from a checkout without submodules,
so it can't quietly stop working.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LxhELiLtpUFwrPSWwTYdHG
Both tools could read MapLibre Tiles but only ever wrote Mapbox Vector
Tiles, so there was no way to convert a tileset into MLT, or to keep a
tileset in MLT once it had been through either of them.
Give them the same --output-format, --pretessellate, and
--no-mlt-feature-sort options that tippecanoe has. tile-join writes the
chosen format to mbtiles files, PMTiles archives, and tile directories,
naming directory tiles and the tileset metadata format accordingly, and
tippecanoe-overzoom writes it to its output tile. Either tool will read
whichever format its sources are in regardless of what it is writing.
The output format selection and the MLT encoder options now live in
mlt.cpp, shared by all three tools rather than defined in main.cpp for
tippecanoe alone, along with encode_tile() for encoding a tile in the
selected format. overzoom() takes the format as a parameter, since
tile-join uses it internally to rescale tiles that will be re-encoded
afterward, and those intermediate tiles should stay MVT.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LxhELiLtpUFwrPSWwTYdHG
Tilesets written with --output-format=mlt could not be read back by any of
tippecanoe's own tools, which made MLT a dead end rather than a tile format.
Build the mlt-cpp decoder from the vendored maplibre-tile-spec submodule
alongside the encoder, and convert a decoded MapLibre Tile back into the
equivalent mvt_tile: geometry, feature ids, and property columns. MLT rings
come back explicitly closed, so the repeated final point becomes an MVT
closepath, and the property columns, which are held in an unordered map,
are sorted by name so that the attributes of a decoded tile come out in a
stable order.
Rather than adding an option to each tool, mvt_tile::decode() detects the
encoding and dispatches, so everywhere tippecanoe already reads a vector
tile can read MLT. An MLT tile begins with a varint layer length followed
by a varint layer tag whose only defined value is 1, while an MVT tile is
a protobuf whose only field is the repeated layer field 3, so it begins
with 0x1a followed by a layer length that can never be as short as the one
byte that would be needed to look like an MLT layer tag.
Tile directories also needed a fix: enumerate_dirtiles() recognized .mlt
file names but still recorded .pbf as the extension to read them back
with, so decoding an MLT directory failed to find any of its tiles.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LxhELiLtpUFwrPSWwTYdHG
An MLT property column has one type for the whole layer, while MVT values
are individually typed. Converting each value on its own left the encoder
to reconcile the mismatch, and its fallback for a column holding both
integers and doubles is to encode the whole column as strings, so an
attribute like gdp_md_est in tests/ne_110m_admin_0_countries turned into
values like "904.200000".
Summarize each attribute across the layer first and pick one type that can
hold all of its values, so mixed integer and floating point columns become
doubles. Only columns that mix numbers with strings, or booleans with
numbers, still fall back to strings, which is as close as MLT's typed
columns can get.
Also stop encoding JSON-object-valued attributes as MLT struct columns.
Struct children can only be strings, and a struct column is flattened into
"column name + child name" when it is read back, so an attribute `meta`
holding {"en": "one", "de": "eins"} decoded as separate `metaen` and
`metade` attributes. Nested JSON now stays JSON text, the way MVT
carries it.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01LxhELiLtpUFwrPSWwTYdHG
* wagyu: drop a hole no remaining ring can parent instead of throwing
correct_tree() throws "Could not properly place hole to a parent" when
topology correction leaves a hole whose parent ring was removed (degenerate
input such as stacked duplicate rings from coalesced tiny-polygon
placeholders). That aborts the entire tiling run over one unrepresentable
sliver. Remove the ring and its points instead, matching how other
unresolvable degeneracies are handled.
* Add a regression test for dropping an unplaceable hole
A fuzzer-minimized pair of mutually reversed self-intersecting rings that
makes wagyu's correct_tree fail to find a parent for a hole — the same
failure reported in mapbox/tippecanoe#761. Before the topology_correction
change, running this test exits with EXIT_IMPOSSIBLE via the polygon
cleaning error handler; with it, the clean returns.
Don't prune variable-depth children while a minzoom-gated feature is pending
The minzoom_feature_pending flag from #397 keeps a variable-depth pyramid
subdividing until explicit per-feature minzooms are satisfied, but two gaps
let features still be dropped:
The flag was only set when tippecanoe_minzoom > z + 1, so a feature whose
minzoom is exactly z + 1 never marked the tile pending, even though a leaf
at z carries only z-visible content.
The early-stop commit never consulted the flag: a tile that succeeded in
stopping early inserted itself into skip_children_out unconditionally,
pruning the children the pending feature needed. The flag only inflated
estimated_complexity_out, which the pruning ignores.
Set the flag for any feature excluded below its minzoom, include it in the
early-stop veto, and skip child pruning while it is set. Adds a fixture
covering the minzoom == z + 1 boundary; make test passes with no diffs to
existing fixtures.
--generate-variable-depth-tile-pyramid decides a tile is a leaf once its
geometry fits at full detail, then prunes the tile's entire subtree. The
guard that prevents leafing while deeper content is still pending consults
only feature_minzoom (the automatic dot-dropping zoom); it does not consult
tippecanoe_minzoom, the explicit per-feature minzoom set via the
tippecanoe.minzoom attribute.
So a feature carrying an explicit minzoom deeper than where its region leafs
is excluded from the leaf tile (z < minzoom) while its children are never
generated. It ends up in no tile at any zoom, silently dropped.
next_feature() excludes such a feature and continues without returning it,
so the leaf-prevention guard in write_tile() never sees it. Carry a flag out
of next_feature() when an excluded feature first appears beyond the next
zoom, and feed it into the same estimated-complexity path feature_minzoom
already uses, so the pyramid keeps subdividing down to the feature's minzoom.
The flag only affects estimated_complexity_out, which is written solely under
--generate-variable-depth-tile-pyramid, so builds without that flag are
unchanged. make test passes with no fixture diffs.
Integrate the C++ MLT encoder from maplibre-tile-spec as a submodule.
Tiles are encoded by converting the existing mvt_tile to
mlt::Encoder::Layer and calling the encoder library directly.
New CLI flags:
--output-format=mlt Encode tiles as MLT instead of MVT
--pretessellate Pre-triangulate polygons (MLT only)
--no-mlt-feature-sort Disable within-tile Hilbert sorting (MLT only)
MLT tiles use .mlt extension in directory output and format=mlt in
mbtiles metadata. Compression and all existing flags work unchanged.
Enhance fqsort function to accept a temporary directory parameter for file handling. Update calls to fqsort in main.cpp, sort.cpp, sort.hpp, and unit.cpp to utilize the new parameter, ensuring temporary files are created in the specified directory.
* Divide-and-conquer polygon cleaning
* Catch the case where the gap can't be increased further
* Catch the case where we try to keep impossibly many features
* Make label points earlier in the tiling process
* Another case where it could try to drop even after already limiting.
* And do not coalesce on impossibly small geometries
* Add missing return
* Update version and changelog
* Improve the memory spike during tile construction
* Remove `need_tilestats`. Add a bunch of debug logging
* Remove debug logging
* Update version and changelog
* Add a flag to use an H3 index for the feature index
* Give mvt_value and serial_val a double-with-count concept
* Switch mean over to internal accumulation state
* Get rid of the attribute accumulation map
* Change vectors of features to vectors of pointers to features
* Fix --coalesce
* Revert "Add a flag to use an H3 index for the feature index"
This reverts commit b9b48f42c9.
* Update version and changelog
* Sketching out sqlite options for tile-join
* Enable sqlite3 serialized multithreading
* Fix some unnecessary round trips from std::string to char * and back
* Gathering join keys for sql query
* Make a query
* Actually open the gpkg. Fix the query quoting.
* Actually do the query and get results back
* Join the attributes onto the feature
* Set matched if the sql join matches
* Add a flag to get the feature ID from the query
* Observe attribute exclusion when joining from sql queries
* Add a flag to exclude all attributes from the tile side of the join
* Make tile-join bounding boxes reflect feature bounds, not tile bounds
* More tests
* An empty tileset has empty bounds at null island
* Gather the results from each thread *after* the thread finishes
* Missed a test
* Fix accidental inclusion of the top left of the tile in the bbox
* Case smashing and prefix trimming in the select
* Add test of sql join
* Make the join column option a join expression option
* Fix antimeridian adjustment. Z0 can't wait until the end of the tile
* Checkpoint on accepting multiple joined rows per tiled feature
* Adding the joined attribute should be per-feature, not per-attribute
* Forgot to update the test. Order of joined attributes has changed.
* Get the attributes back in the right order
* Add test of sql join with limit
* Allow multiple tile features to have the same join key
* Update tests for a country name with two distinct geometries
* Update version and changelog
* Forgot to mention the bounding box improvements
* Make tippecanoe-overzoom accept filters from a file
* Accept clip polygons from a file too
* Add test of clipping by polygon from file
* Add a test of reading an overzoom filter from a file
* Update version and changelog
* Plumb a clip bounding box around through overzoom
* Actually do some clipping
* Add a test
* Fix post-binning clipping
* Factoring out geometry parsing from feature parsing
* Accept a clip polygon argument to tippecanoe-overzoom
* Progress in the direction of polygon clipping
* Fix the wagyu flags. We need intersection, not union
* Remove debug spew
* Clip points to polygon bounds too
* Copy the geometric binning code to serve as intersection-finding code
* Add clipper2 for linestring clipping
* Compiles, but does not actually seem to clip. Hmm.
* Oh, it helps if I actually call the function
* Add clipping tests
* Add missing fixture, and don't crash if it is missing
* Remember to do polygon clipping after binning too
* Fix scaling before post-binning clipping. Add test.
* Remove unused parts of clipper
* Rename for consistency
* Revert accidentally added line
* Clip the clip regions to the tile bounds to reduce their complexity
* Add a test of clipping the clip region down to the tile boundary
* Update version and changelog
* Strip out unwanted attributes earlier in the process
* Skip aggregations whose attributes have been excluded
* Forgot one
* Add some more tests
* Update version and changelog
* Add a tippecanoe-decode option to restrict which attributes to decode
* Plumb buffer and feature limit around
* Check the feature limit
* Clarifying cases where output detail can be unspecified
* Clip bins to the tile buffer instead of just passing them through
* Add missing include
* Missed some tests
* Add --no-tile-compression option to tippecanoe-overzoom
* Update version and changelog
* Progress on plumbing a string pool for full_keys through
* More plumbing for key_pool
* Don't keep features with identical locations as multiplier features
* Revert "Don't keep features with identical locations as multiplier features"
This reverts commit 413f0c8024.
* Adjust calculated maxzoom to account for duplicate feature locations
* Update changelog and version
* Add a test affected by the maxzoom change with duplicate locations
* Round the drop rate a little for cross-platform test consistency
* Add an all-mvt_value attribute accumulation path
* Only bin by ID, not geometrically
* A little cleanup; changelog and version; test
* Remove accidental double-conversion
* Replace duplicated code with template
* Update changelog
* Choose the megatile features from those that will be in the next N zooms
* Take fractional zooms into account in multiplier feature choices
* Fix more tests
* Add a flag to retain multiplier features by minimum distance
* Limit feature expansion from multiplier density to 2x
* The multiplier cap was a bad idea
* Revert "The multiplier cap was a bad idea"
This reverts commit 6f8273a4c8.
* Revert "Limit feature expansion from multiplier density to 2x"
This reverts commit a26e41309d.
* Revert "Add a flag to retain multiplier features by minimum distance"
This reverts commit 01f14a4255.
* Remove the multiplier sequence, which should no longer matter
* Revert "Revert "Add a flag to retain multiplier features by minimum distance""
This reverts commit 776da4a1b8.
* Revert "Revert "Limit feature expansion from multiplier density to 2x""
This reverts commit 44a683d808.
* Revert "Revert "The multiplier cap was a bad idea""
This reverts commit 80f7cb1c0e.
* Track two kinds of previous index for next_feature
* Fix multiplier density threshold, I think
* Oh, I didn't git add the code changes
* Update version and changelog
* Try to install sqlite3 to fix the automated build
* Deleted too much
* Only let --preserve-point-density-threshold shift density around
* Remove the density debt concept, since it doesn't help
* Make the drop states a vector instead of an array
* Revert "Make the drop states a vector instead of an array"
This reverts commit 66c7abb6fa.
* Revert "Remove the density debt concept, since it doesn't help"
This reverts commit 707bb0c562.
* Revert "Only let --preserve-point-density-threshold shift density around"
This reverts commit ecf01f2231.
Claude