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
* Put all of this back in geometry.cpp for conflict resolution
* Stabilize line simplification to behave the same regardless of winding
* Round instead of truncating when clipping lines
* Restore non-Wagyu polygon clipping from prior to 2fdec7d2
* Make it round, not truncate, which reverts the last commit's test diffs
* Clip in floating point, not integers, which makes no difference
* Track nodes added at tile edges during clipping
* Scale geometry up before wagyu to prevent changes from precision loss
* Actually do the shared edge detection
* Fix cases where nodes were not being added at the tile boundary
* One more place I should have rounded
* Narrow down where the discrepancy comes in
* Revert "Narrow down where the discrepancy comes in"
This reverts commit 221c4c5fc0ac9a6567e091c6a94b3d87dc8ade83.
* Another attempt to narrow it down
* The discrepancy seems to be introduced in reordering. No obvious bug
* Was still truncating instead of rounding in projection
* Also makes no difference...
* Just forget that line reversal exists for a minute
* Just reversal no coalescing
* Try clipping in integers instead of floating point
* Don't simplify after coalescing if they said no simplification
* Check whether behavior is consistent with intentional simplification
* Replace more floating point with integer
* Are these three features enough to demonstrate the problem?
* Add a few more nearby borders
* All the features that touch tile 6/16/23
* Stay in integers in line simplification
* More attempts to solve failures to simplify consistently
* Fix most of the overflow errors
* Fix known cases of integer overflow
* All the tests change again
* Pull clipping and scaling code back out into clip.cpp
* Resolve the test conflicts
* Stabilize choice of which three points to keep with different windings
* Almost right, I think!
* Fix collapse of islands to shards
* Self-intersections in the same feature don't count
* Revert "Self-intersections in the same feature don't count"
This reverts commit e04b19916e.
* Don't scale down geometry if we are going to look for shared nodes
* Fix the missing multiply that was keeping simplification from happening
* Fix one more opportunity for overflow
* Somehow I deleted this test?
* Lost this test too
* Clean up debugging printfs
* Restore code sequence from main to make it reviewable
* Remove unneeded rounding
* Update documentation
* This test is no longer useful
* Back to floating point Douglas-Peucker to fix undersimplification
* Try an older ubuntu
* Revert "Try an older ubuntu"
This reverts commit 13fefacfd7.
* Log OS info
* Remove tests that are no longer needed
* Oops, did need that one after all
* Fix the arm vs x86 discrepancy?
* Try another quantization
* Cleanup from review
* Add a test for the actual purpose of this PR
* Dropping a 0-length feature doesn't count as dropping-as-needed
* Add an option not to reduce tiny polygons to dust at maxzoom
* Add test for prevention of tiny polygon reduction at maxzoom
* Fix accounting for tiny polygons not to include degenerate geometries
* Revert "Add test for prevention of tiny polygon reduction at maxzoom"
This reverts commit f931bbd73e.
* Revert "Add an option not to reduce tiny polygons to dust at maxzoom"
This reverts commit 03f0882bb6.
* Fix tests
* Another test that no longer has any really tiny polygons
* Oops, that broke LineString simplification
* This time for sure!
* Update changelog and version
* Turn off unit, which has bit-rotted
* Instrument line simplification
* Do more work in integer space
* Update tests with simplification done with more integers
* Clean up
* Update changelog
* Eradicate calls to deprecated sprintf()
* Revert "Turn off unit, which has bit-rotted"
This reverts commit 998779313f.
* Fix catch by switching to an unsigned type
* Calculate a new antimeridian-adjusted bounding box
* Add antimeridian bounding box to pmtiles, dirtiles, and tile-join
* Don't take out-of-bounds latitudes into account in the adjusted bbox
* Update changelog
* Forgot to adjust tests after the last change
* Round coordinates instead of truncating them
* Update all the tests for coordinate rounding changes
* Curses, integer division still truncates
* Fix tests
* Also round instead of shifting when looking for no-op linetos
* Should I worry that the same change for moveto doesn't change any tests?
* Also round instead of shifting when scaling down to maxzoom resolution
* Replace another explicit shift, for origin point
* Round instead of shift when writing clipped geometries to the next zoom
* Fix low-zoom gridding and smaller-than-a-pixel checks
* Don't guess an excessively large maxzoom when there is only one feature
* Add a test for guessing the maxzoom of a single point
* Explicitly sort by index if no other order distinguishes features
* Another affected test
* add pmtiles.hpp from github.com/protomaps/PMTiles [#10]
* tippecanoe main writes pmtiles output. [#10]
* detect output format using suffix
* after mbtiles is done writing, replace with pmtiles based on map/image tables.
* add method to write_json for writing json sub-object.
* tippecanoe-decode reads pmtiles input. [#10]
* tile-join reads and writes pmtiles. [#10]
* pmtiles test suite for decode and tile-join [#10]
* add base GitHub CI action for compiling and test suite.
* update pmtiles.hpp with z>15 fix
* Fix some ordering problems with pmtiles decode
* Pmtiles should also pass the raw tiles tests
* Eradicate spaces from tileset metadata JSON fields
* Eradicate spaces from more test fixtures
* Update more tests
* Pmtiles tests pass now too
* Remove unnecessary sort (and make indent)
* Update changelog
* The allow-existing test for pmtiles needs -o, not -e
* Declare --allow-existing to be unsupported for pmtiles.
It was always a bad idea even for mbtiles.
Co-authored-by: Brandon Liu <bdon@bdon.org>
* Reduce maxzooms being guessed a little:
* Use 1.5 standard deviations, not 2, as the minimum distinguishable
* Give overlapping polygons and linestrings more distinct indices
* Add another drop rate guessing options, from the same metrics -zg uses
* Guard against using -rp without -zg
* Add an option to retain extra coordinate precision at maxzoom
* Make sure not to shift away the extra detail from coordinates
* Add an option to convert double-precision attributes to single
* Sort attribute values in tiles to make them compress a little better
* Slightly improve polygon simplification
By choosing a point that would be retained after simplification
to be the start/end point that always gets retained
* I regret making all of these tests involve polygons
* Add an option to specify the size of tiny polygons
* Fix accidental requiring of argument for --single-precision
* Guard against duplicate points when generating "sizes" for them
* Restore the intended behavior that tiny polygons don't get simplified
* Make the extra detail settable rather than always maximizing it
* Revert "Improve maxzoom guessing for tightly-clustered point data sources (#4)"
This reverts commit fec5e8354c.
* Add an option to prevent choosing a base zoom higher than the maxzoom
* Keep the drop rate high enough when the basezoom gets constrained
* Revert "Revert "Improve maxzoom guessing for tightly-clustered point data sources (#4)""
This reverts commit db6bc27d9e.
* Add --order-by and --order-descending options
* Accept multiple --order-by and --order-descending-by sort keys
Claude