Add --generate-variable-depth-tile-pyramid option (#251)

* Track output position at the file level instead of within each tile

* Track file position where the child tile data begins

* Add option and document its intended behavior

* Changing the detail loop to account for stopping early

* I forgot I already added an option for this

* Stop early if we can make a complete tile

* Add a test of zoom truncation with limited feature count

* Forgot to commit the actual code change

* Make room for a vertex count in the header of each serialized tile

* Estimate tile complexity; don't try truncating when unlikely to work

* Be more conservative, because ever retrying a tile is a big speed hit

* If stopping early, don't simplify or clean; leave that to overzoom

* Add tiny polygon reduction / dust to overzoom

* Don't try to stop early in the children if we dropped anything by rate

* Fflush here too before pwriting

* Don't stop early if we ended up dropping any features.

Rework the can-the-next-zoom-stop-early logic to avoid going
one zoom further than needed.

* Fix warning

* Fix warnings

* Oops, checking for the wrong expected return value

* Cleanup from adding line simplification in overzoom

* Current (wrong) behavior when combining coalescing and truncating

* Keep a list of parent tiles to skip rather than truncating

* Now the coalesced tiles in z12 get children in z13

* Don't double-count feature dropping when the zoom level is retried

* Correct README description

* Remove todo about special case below basezoom, which is accounted for

* Be a little more aggressive in drop-densest determination

* Scale tile feature limit for megatiles in the same way as byte limit

* Fully deprecate -detect-shared-borders into an alias

* Track the distances found in the douglas-peucker recursion

* Serialize and deserialize the distance with the vertices

* Revert "Serialize and deserialize the distance with the vertices"

This reverts commit 753f1b7909.

* Revert "Track the distances found in the douglas-peucker recursion"

This reverts commit e5361f8c22.

* Revert "Fully deprecate -detect-shared-borders into an alias"

This reverts commit 0698aeb766.

* Better tracking of whether we failed to make a full-detail tile

* Put a bloom filter in front of the binary search for shared nodes

* Forgot to take out this printf

* Improve dispatch of tiling tasks

* Still dispatch the biggest tasks first

* Track zoom truncation in the strategies list in the tileset metadata

* Prescan for small deltas before doing proper simplification

* Revert "Prescan for small deltas before doing proper simplification"

This reverts commit d1d8238b83.

* Update version and changelog

* Rename to --generate-variable-depth-tile-pyramid

shared_borders.cpp

@@ -196,7 +196,7 @@ bool find_common_edges(std::vector<serial_feature> &features, int z, int line_de
 								}
 
 								if (e1.first == e1.second || e2.first == e2.second) {
-									fprintf(stderr, "Internal error: polygon edge lookup failed for %lld,%lld to %lld,%lld or %lld,%lld to %lld,%lld\n", left[0].x, left[0].y, left[1].x, left[1].y, right[0].x, right[0].y, right[1].x, right[1].y);
+									fprintf(stderr, "Internal error: polygon edge lookup failed for %lld,%lld to %lld,%lld or %lld,%lld to %lld,%lld\n", (long long) left[0].x, (long long) left[0].y, (long long) left[1].x, (long long) left[1].y, (long long) right[0].x, (long long) right[0].y, (long long) right[1].x, (long long) right[1].y);
 									exit(EXIT_IMPOSSIBLE);
 								}
 
@@ -357,7 +357,7 @@ bool find_common_edges(std::vector<serial_feature> &features, int z, int line_de
 		}
 		if (!(prevent[P_SIMPLIFY] || (z == maxzoom && prevent[P_SIMPLIFY_LOW]) || (z < maxzoom && additional[A_GRID_LOW_ZOOMS]))) {
 			// tx and ty are 0 here because we aren't trying to do anything with the shared_nodes_map
-			simplified_arcs[ai->second] = simplify_lines(dv, z, 0, 0, line_detail, !(prevent[P_CLIPPING] || prevent[P_DUPLICATION]), simplification, 4, drawvec(), NULL, 0);
+			simplified_arcs[ai->second] = simplify_lines(dv, z, 0, 0, line_detail, !(prevent[P_CLIPPING] || prevent[P_DUPLICATION]), simplification, 4, drawvec(), NULL, 0, "");
 		} else {
 			simplified_arcs[ai->second] = dv;
 		}