func writeNodes(file *os.File, nodes []node) error {
if len(nodes) == 0 {
return nil
}
for nodeGroupIndex := 0; nodeGroupIndex < (len(nodes)/8000)+1; nodeGroupIndex++ {
beg := (nodeGroupIndex + 0) * 8000
end := (nodeGroupIndex + 1) * 8000
if len(nodes) < end {
end = len(nodes)
}
nodeGroup := nodes[beg:end]
stringTable := make([][]byte, 1, 1000)
stringTableIndexes := make(map[string]uint32, 0)
for _, node := range nodeGroup {
for _, s := range node.keys {
idx := stringTableIndexes[s]
if idx == 0 {
stringTableIndexes[s] = uint32(len(stringTable))
stringTable = append(stringTable, []byte(s))
}
}
for _, s := range node.values {
idx := stringTableIndexes[s]
if idx == 0 {
stringTableIndexes[s] = uint32(len(stringTable))
stringTable = append(stringTable, []byte(s))
}
}
}
osmNodes := make([]*OSMPBF.Node, len(nodeGroup))
for idx, node := range nodeGroup {
osmNode := &OSMPBF.Node{}
var nodeId int64 = node.id
osmNode.Id = &nodeId
var rawlon int64 = int64(node.lon/.000000001) / 100
var rawlat int64 = int64(node.lat/.000000001) / 100
osmNode.Lon = &rawlon
osmNode.Lat = &rawlat
osmNode.Keys = make([]uint32, len(node.keys))
for i, s := range node.keys {
osmNode.Keys[i] = stringTableIndexes[s]
}
osmNode.Vals = make([]uint32, len(node.values))
for i, s := range node.values {
osmNode.Vals[i] = stringTableIndexes[s]
}
osmNodes[idx] = osmNode
}
group := OSMPBF.PrimitiveGroup{}
group.Nodes = osmNodes
block := OSMPBF.PrimitiveBlock{}
block.Stringtable = &OSMPBF.StringTable{stringTable, nil}
block.Primitivegroup = []*OSMPBF.PrimitiveGroup{&group}
err := WriteBlock(file, &block, "OSMData")
if err != nil {
return err
}
}
return nil
}
