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Home - General / All posts - selection of item on drawing from geojson file
lionel

540 post(s)
#14-Dec-18 19:41

Hi

A) i import a geojson file from france inside Manifold 9 ( cut..Edge) and don't succeed to select items locate inside drawing !! (I use keyboard press Ctrl and then mouse cursor click to seelct item )

1) add index on new mfd_id field don't work for enable selection

I add using schema a field mfd_id and a index mdf_id_x using btree on the mfd_id field . After this i was thinking i could select in drawing some item but not .

2) copy table create new table work

If i copy /paste the the table and create a new drawing base on this table then i can select item locate inside the drawing !!

Is it the default mfd9 behaviour ?

B) Does the geojson file spec define the default projection tourn:ogc:def:crs:OGC::CRS84

Does crs84 mean, is equivalent to EPSG:4326 ?

where is the table mamping beetween crs and epsg ?

where can i have more information about datum and latitude and longitude reference ?

regard's

Attachments:
communes-06-alpes-maritimes.geojson


join image "Because my dad promised me" ( interstellar ) but blackhole don't exist because of inversion of mass .Does the next Einstein Model name ll be the janus model ?!

lionel

540 post(s)
#14-Dec-18 20:16

C) strange if i capture screen manifold 9 and geosjon online editor the shape don't match !!

Does projection rendering change ?

Attachments:
geojson_online.png


join image "Because my dad promised me" ( interstellar ) but blackhole don't exist because of inversion of mass .Does the next Einstein Model name ll be the janus model ?!

lionel

540 post(s)
#14-Dec-18 21:41

in raster software the tools for transform image layer ( scale in horizontal and vertical ) let us see that the 2 image can match the second bounding shape area !


join image "Because my dad promised me" ( interstellar ) but blackhole don't exist because of inversion of mass .Does the next Einstein Model name ll be the janus model ?!

adamw


8,289 post(s)
#18-Dec-18 14:44

I am not sure why the data does not line up, it seems to line up in 9 with Bing imagery just fine:

(The GeoJSON is semi-transparent and is overlaid on top of the Bing image.)

The overlay is good regardless whether the coordinate system is pseudo-Mercator (vector gets projected to raster) or lat/lon (raster gets projected to vector).

PS: Wait, "capture screen"? You mean you opened the drawing in Manifold, captured a screen, and it is that screen that does not line up with what you see in Mapbox? That's almost certainly different projections - your screen is likely lat/lon and Mapbox screen is likely pseudo-Mercator.

Attachments:
geojson-ontopof-bing.png

adamw


8,289 post(s)
#18-Dec-18 14:36

A - Importing the file produces a table with no unique index, but adding MFD_ID (INT64) and MFD_ID_X (BTREE on MFD_ID) makes the table editable. If you first open the drawing, then add the field and the index, then the drawing window does not understand that the table just became editable and you have to close and reopen it - we will fix this.

B - GeoJSON is always lat/lon, WGS84. That's the same as urn:ogc:def:crs:OGC:xxx:CRS84 and almost the same as EPSG:4326. The difference is the order of the coordinate axes, GeoJSON uses XY (lon/lat) and EPSG:4326 uses YX (lat/lon).

URN extensions for OGC are described in OGC docs, eg, in OGC 07-092r3. In addition to CRS84 they define CRS27, CRS83 roughly analogous to NAD27, NAD83 and several other constants.

lionel

540 post(s)
#19-Dec-18 02:32

Thank's a lot for your reply.

Yes i do capture screen . the post image show two images capture screen edit inside paint net . i use transparency to place manifod capture screen on top.

I scale One to fit thé other One ..


join image "Because my dad promised me" ( interstellar ) but blackhole don't exist because of inversion of mass .Does the next Einstein Model name ll be the janus model ?!

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