Our Goal is to create Geo-json as light-weight as possible. In order to achieve this we are making Geo-json properties key and value as small as possible.
From:
{
"type": "Feature",
"geometry": {
"type": "Point",
"coordinates": []//coordinates
},
"properties": {
"rotation": 0, //<-- Notice Keys
"size": 0.609524,
"text": "143",
"text-justify" : "left"
}
},
To
{
"type": "Feature",
"geometry": {
"type": "Point",
"coordinates": []//coordinates
},
"properties": {
"r": 0,
"s": 0.609524,
"t": "143",
"tj": "l" //"l" is "left", "r" is right and "c" is center
}
},
And then on frontend while adding layer, will do something like below:
"layout": {
"text-justify": ['get', 'tj'] //<--- How to create this expression
"text-field": ['get', 't'],
"text-size":
[
'interpolate',
['exponential', 1.75],
['zoom'],
1, ["/", ["get", "s"], 5.15],
11, ["/", ["get", "s"], 0.01]
],
"text-rotate": ['get', 'r'],
}
So my question is: How to write expression for "text-justify" property as value's are "l"/"r"/"c" to be "left"/"right"/"center"?
You can write it like this:
"text-justify": ['match', ['get', 'tj'],
'l', 'left',
'r', 'right',
//...
'center'
]
If your goal is to send large data files statically to the browser, you might want to look at Geobuf as a more space-efficient format.
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