README
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Flatrtree - Go
Flatrtree is a serialization format and set of libraries for reading and writing R-trees. It's directly inspired by Flatbush and FlatGeobuf, and aims to make tiny, portable R-trees accessible in new contexts.
- Store R-trees to disk or transport them over a network.
- Build R-trees in one language and query them in another.
- Query R-trees before reading the data they index.
Installation
Requires Go 1.18 or later.
$ go get github.com/flatrtree/flatrtree-go
Usage
Flatrtree separates building and querying behavior. The builder doesn’t know how to query an index and the index doesn’t know how it was built. This is inspired by FlatBuffers.
Serialization
Flatrtree uses protocol buffers for serialization, taking advantage of varint encoding to reduce the output size in bytes. There are many tradeoffs to explore for serialization and this seems like a good place to start. It wouldn’t be hard to roll your own format with something like FlatBuffers if that better fit your needs.
Documentation
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Index ¶
Constants ¶
const DefaultDegree int = 10
Variables ¶
This section is empty.
Functions ¶
func GeodeticBoxDist ¶
GeodeticBoxDist returns the distance in meters between the point and rect
func PlanarBoxDist ¶
PlanarBoxDist returns the squared distance between the given point and rect
Types ¶
type HilbertBuilder ¶
type HilbertBuilder struct {
// contains filtered or unexported fields
}
func NewHilbertBuilder ¶
func NewHilbertBuilder() *HilbertBuilder
func (*HilbertBuilder) Add ¶
func (b *HilbertBuilder) Add(ref int64, minX, minY, maxX, maxY float64)
type OMTBuilder ¶
type OMTBuilder struct {
// contains filtered or unexported fields
}
func NewOMTBuilder ¶
func NewOMTBuilder() *OMTBuilder
func (*OMTBuilder) Add ¶
func (b *OMTBuilder) Add(ref int64, minX, minY, maxX, maxY float64)
type RTree ¶
type RTree struct {
// contains filtered or unexported fields
}
func Deserialize ¶
func (*RTree) Neighbors ¶
func (r *RTree) Neighbors( x, y float64, iterf func(ref int64, dist float64) (next bool), boxDist func(pX, pY, minX, minY, maxX, maxY float64) (dist float64), itemDist func(pX, pY float64, ref int64) (dist float64), )
Neighbors calls the iterf function for all items in ascending order of distance to the given coordinates. If iterf returns false the search will terminate.
Distances are calculated with the boxDist function. The itemDist function can optionally be supplied to calculate a more accurate distance to items in the index. Take care that itemDist and boxDist return distances in the same units.
Source Files
Directories