Daniel J. H.

Map makes unnecessary repeated requests against a source's tile

11

Hey folks, I ran into this issue when shipping an overview map displaying vector tiles with a single tile on zoom level zero. Meaning - I have a vector tile...

Extractor: clean up and normalize station names

4

I just had a look at the Berlin GTFS feeds for this year. > https://daten.berlin.de/datensaetze/vbb-fahrplandaten-januar-2017-bis-dezember-2017 > stops.txt, CC-BY 3.0 licensed: http://www.vbb.de/de/datei/GTFS_VBB_Jan_Dez2017.zip I can see three concrete issues: 1/ In there...

Verify builtins get compiled into asm instructions we want

1

We are using `__builtin` calls in some of our bit manipulation functions. The idea is that the compiler will turn the builtin calls to native instructions, when compiled with the...

Please read https://github.com/tinygraph/tinygraph/issues/14 for context. This changeset adds a first take on succinct rank/select data structures based on http://www.cs.cmu.edu/~dga/papers/zhou-sea2013.pdf - named "poppy" > "Space-efficient, high-performance rank and select structures on...

Undirected Graphs

2

We should provide an undirected graph abstraction. At the moment the csr graph is directed. For use what we have and turn it into an undirected graph, we'll need -...

We want to provide API and ABI stability - checking it can be done e.g. with the following tool - https://lvc.github.io/abi-compliance-checker/ - https://github.com/lvc/abi-compliance-checker Ideally we'd run this continuously e.g. in...

We are starting out with modern x86-64 hardware targets starting with Haswell+ for instructions like popcount, etc. - https://github.com/tinygraph/tinygraph/issues/11 In addition we should look into the neon instruction set, for...

Implement Rank/Select

8

We should look into implementing rank/select structures for bitset / elias-fano https://github.com/tinygraph/tinygraph/issues/13 For example have a look at > "Space-efficient, high-performance rank and select structures on uncompressed bit sequences" by...

Elias-Fano Coding

3

One idea is run-length encoding offsets https://github.com/tinygraph/tinygraph/issues/12 - which will probably work quite well with very sparse graphs like road networks. Another idea is Elias-Fano coding, since offsets are monotonically...

Custom C allocator interface

1

At the moment we use calloc / malloc / free for dynamic memory allocation. We should allow for custom memory allocators. Look into how to best support custom allocators.