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GEoJSON geometry replacement issue.

  • 11 September 2018
  • 5 replies
  • 16 views
amolparande
Badge +1

Hello everyone ,

I have two JSON files

1. RoadElement.json

2. WaterArea.json

I want to create geometry from each JSON file that would be polyline

& Polygon features

I have also created FME workbench but could not able to

create Geometry having some problem can any one help me what is wrong?

Please find attached JSON file and created Workbench

icon

Best answer by nielsgerrits 11 September 2018, 11:35

View original

5 replies

nielsgerrits
Rank
Userlevel 6
Badge +33

I think the data doesn't validate as correct GeoJSON.

The structure for a polygon feature should be:

{
    "type": "Polygon",
    "coordinates": [
        [
            [
                100,
                0
            ],
            [
                101,
                0
            ],
            [
                101,
                1
            ],
            [
                100,
                1
            ],
            [
                100,
                0
            ]
        ]
    ]
}

Where a piece in waterarea.json is:

{
	"type": "coordinates",
	"coordinates": [[145.71758,
	-30.83595],
	[145.71769,
	-30.83532],
	[145.71895,
	-30.8348],
	[145.72022,
	-30.83381],
	[145.72158,
	-30.83383],
	[145.72241,
	-30.83428],
	[145.72374,
	-30.83646],
	[145.72404,
	-30.83773],
	[145.72403,
	-30.83846],
	[145.72028,
	-30.83697],
	[145.71872,
	-30.83623],
	[145.71758,
	-30.83595]]
}

Issues are:

  • type should be Polygon, not coordinates (case sensitive!)
  • the array of coordinates should be nested one level deeper (rings, ring, coordinatepairs)
  • polygons should follow the right-hand rule (exterior rings are counter clockwise, interior rings / holes are clockwise)

See the spec.

This works for me:

{
	"type": "Polygon",
	"coordinates": [[[145.71758,
	-30.83595],
	[145.71872,
	-30.83623],
	[145.72028,
	-30.83697],
	[145.72403,
	-30.83846],
	[145.72404,
	-30.83773],
	[145.72374,
	-30.83646],
	[145.72241,
	-30.83428],
	[145.72158,
	-30.83383],
	[145.72022,
	-30.83381],
	[145.71895,
	-30.8348],
	[145.71769,
	-30.83532],
	[145.71758,
	-30.83595]]]
}
amolparande
Badge +1

I think the data doesn't validate as correct GeoJSON.

The structure for a polygon feature should be:

{
    "type": "Polygon",
    "coordinates": [
        [
            [
                100,
                0
            ],
            [
                101,
                0
            ],
            [
                101,
                1
            ],
            [
                100,
                1
            ],
            [
                100,
                0
            ]
        ]
    ]
}

Where a piece in waterarea.json is:

{
	"type": "coordinates",
	"coordinates": [[145.71758,
	-30.83595],
	[145.71769,
	-30.83532],
	[145.71895,
	-30.8348],
	[145.72022,
	-30.83381],
	[145.72158,
	-30.83383],
	[145.72241,
	-30.83428],
	[145.72374,
	-30.83646],
	[145.72404,
	-30.83773],
	[145.72403,
	-30.83846],
	[145.72028,
	-30.83697],
	[145.71872,
	-30.83623],
	[145.71758,
	-30.83595]]
}

Issues are:

  • type should be Polygon, not coordinates (case sensitive!)
  • the array of coordinates should be nested one level deeper (rings, ring, coordinatepairs)
  • polygons should follow the right-hand rule (exterior rings are counter clockwise, interior rings / holes are clockwise)

See the spec.

This works for me:

{
	"type": "Polygon",
	"coordinates": [[[145.71758,
	-30.83595],
	[145.71872,
	-30.83623],
	[145.72028,
	-30.83697],
	[145.72403,
	-30.83846],
	[145.72404,
	-30.83773],
	[145.72374,
	-30.83646],
	[145.72241,
	-30.83428],
	[145.72158,
	-30.83383],
	[145.72022,
	-30.83381],
	[145.71895,
	-30.8348],
	[145.71769,
	-30.83532],
	[145.71758,
	-30.83595]]]
}
Thank you for replay 

 

What is Wrong with Roadelement.json ?

 

 

nielsgerrits
Rank
Userlevel 6
Badge +33
Thank you for replay

 

What is Wrong with Roadelement.json ?

 

 

Also doesn't follow the spec. The type should be LineString, not coordinates. Just test the part in a online validator like http://geojsonlint.com/
takashi
Rank
Userlevel 2
Badge +17

I think the data doesn't validate as correct GeoJSON.

The structure for a polygon feature should be:

{
    "type": "Polygon",
    "coordinates": [
        [
            [
                100,
                0
            ],
            [
                101,
                0
            ],
            [
                101,
                1
            ],
            [
                100,
                1
            ],
            [
                100,
                0
            ]
        ]
    ]
}

Where a piece in waterarea.json is:

{
	"type": "coordinates",
	"coordinates": [[145.71758,
	-30.83595],
	[145.71769,
	-30.83532],
	[145.71895,
	-30.8348],
	[145.72022,
	-30.83381],
	[145.72158,
	-30.83383],
	[145.72241,
	-30.83428],
	[145.72374,
	-30.83646],
	[145.72404,
	-30.83773],
	[145.72403,
	-30.83846],
	[145.72028,
	-30.83697],
	[145.71872,
	-30.83623],
	[145.71758,
	-30.83595]]
}

Issues are:

  • type should be Polygon, not coordinates (case sensitive!)
  • the array of coordinates should be nested one level deeper (rings, ring, coordinatepairs)
  • polygons should follow the right-hand rule (exterior rings are counter clockwise, interior rings / holes are clockwise)

See the spec.

This works for me:

{
	"type": "Polygon",
	"coordinates": [[[145.71758,
	-30.83595],
	[145.71872,
	-30.83623],
	[145.72028,
	-30.83697],
	[145.72403,
	-30.83846],
	[145.72404,
	-30.83773],
	[145.72374,
	-30.83646],
	[145.72241,
	-30.83428],
	[145.72158,
	-30.83383],
	[145.72022,
	-30.83381],
	[145.71895,
	-30.8348],
	[145.71769,
	-30.83532],
	[145.71758,
	-30.83595]]]
}

@nielsgerrits is right. The format of the JSON documents are similar to GeoJSON, but not GeoJSON. However, you can reconstruct them into the GeoJSON format with some JSON transformers.

 

Example: reconstruct-geojson-example.fmwt (FME 2018.1.0.0)

 

Hope this helps.

jnotter
Rank
Badge +4

@nielsgerrits is right. The format of the JSON documents are similar to GeoJSON, but not GeoJSON. However, you can reconstruct them into the GeoJSON format with some JSON transformers.

 

Example: reconstruct-geojson-example.fmwt (FME 2018.1.0.0)

 

Hope this helps.

I wish I could vote up this particular comment, @takashi. I think this example is what I need to get my data into MapBoxGL-compatible format to color thematic each feature individually. MapBox(leaflet) within HTMLReportGenerator fails to allow the individual formatting capability.

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