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I am trying to convert a .csv file to .dxf using ogr2org from the command line using the following command:

ogr2ogr -f DXF control.dxf opua.vrt

This is the .vrt file I am using:

<OGRVRTDataSource>
  <OGRVRTLayer name="opua">
    <SrcDataSource>opua.csv</SrcDataSource>
    <GeometryType>wkbPoint</GeometryType>
    <LayerSRS>WGS84</LayerSRS>
    <GeometryField encoding="PointFromColumns" x="X" y="Y" z="Z"/>
    <Field name="id" type="String"/>
    <Field name="description"/>
  </OGRVRTLayer>
</OGRVRTDataSource>

The .csv file contains these columns: point#,x,y,z,description. Using the suggestion found here (with the modified command above) produces a .dxf file with properly coordinated points points but no point number or description and two error messages:

ERROR 1: DXF layer does not support arbitrary field creation, field 'id' not created.
ERROR 1: DXF layer does not support arbitrary field creation, field 'description' not created.

I need to know what to do with these two errors to get my point numbers and descriptions to show up next to the points in the .dxf output.

  • According to this rather elderly response from Frank, DXF does not support arbitrary GIS attributes. – scruss Jun 4 '16 at 20:41
  • @scruss Perhaps there is a way to include text labels as explained here. I don't know enough to determine if it would work in this instance. – disconnected Jun 4 '16 at 21:00
  • Also, it seems possible from this response but I don't know how to apply to my script. – disconnected Jun 4 '16 at 23:05
0

You must convert the "description" field of your csv file into label annotation following the DGAL OGR Feature Style specification http://www.gdal.org/ogr_feature_style.html. See a text label example from the section 2.1

A text label, taking the text string from the "text_string"
attribute field: "LABEL(f:"Times New Roman",s:12pt,t:{text_string})"

It is not obvious how such OGR Style string can be build from CSV so it is best to give an example.

Step 1: Have data. Save the following as "opua.csv"

point#,x,y,z,description
1,0,0,122,name_1
2,1,1,222,name_2

Step 2: Make VRT. Reusing your VRT as such:

<OGRVRTDataSource>
  <OGRVRTLayer name="opua">
    <SrcDataSource>opua.csv</SrcDataSource>
    <GeometryType>wkbPoint</GeometryType>
    <LayerSRS>WGS84</LayerSRS>
    <GeometryField encoding="PointFromColumns" x="X" y="Y" z="Z"/>
    <Field name="id" type="String"/>
    <Field name="description"/>
  </OGRVRTLayer>
</OGRVRTDataSource>

Step 3: Use some SQL magic

Test with ogrinfo

ogrinfo -dialect sqlite -sql "SELECT 'LABEL(f:\"Arial\",s:1.5g,t:'||description||')' AS OGR_STYLE, geometry FROM opua" opua.vrt

Result:

INFO: Open of `opua.vrt'
      using driver `OGR_VRT' successful.

Layer name: SELECT
Geometry: Point
Feature Count: 2
Extent: (0.000000, 0.000000) - (1.000000, 1.000000)
Layer SRS WKT:
GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.257223563,
            AUTHORITY["EPSG","7030"]],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0,
        AUTHORITY["EPSG","8901"]],
    UNIT["degree",0.0174532925199433,
        AUTHORITY["EPSG","9122"]],
    AUTHORITY["EPSG","4326"]]
Geometry Column = GEOMETRY
OGR_STYLE: String (0.0)
OGRFeature(SELECT):0
  OGR_STYLE (String) = LABEL(f:"Arial",s:1.5g,t:name_1)
  Style = LABEL(f:"Arial",s:1.5g,t:name_1)
  POINT (0 0 122)

OGRFeature(SELECT):1
  OGR_STYLE (String) = LABEL(f:"Arial",s:1.5g,t:name_2)
  Style = LABEL(f:"Arial",s:1.5g,t:name_2)
  POINT (1 1 222)

Looks good, try conversion into DXF

ogr2ogr -f DXF -dialect sqlite -sql "SELECT 'LABEL(f:\"Arial\",s:1.5g,t:'||description||')' AS OGR_STYLE, geometry FROM opua" opua.dxf opua.vrt

An error message "ERROR 1: DXF layer does not support arbitrary field creation, field 'OGR_STYLE' not created." appears but it is misleading in this context. OGR_STYLE does not get created but it is still converted into DXF style. Test it

ogrinfo opua.dxf entities
INFO: Open of `opua.dxf'
      using driver `DXF' successful.

Layer name: entities
Geometry: Unknown (any)
Feature Count: 2
Extent: (0.000000, 0.000000) - (1.000000, 1.000000)
Layer SRS WKT:
(unknown)
Layer: String (0.0)
SubClasses: String (0.0)
ExtendedEntity: String (0.0)
Linetype: String (0.0)
EntityHandle: String (0.0)
Text: String (0.0)
OGRFeature(entities):0
  Layer (String) = 0
  SubClasses (String) = AcDbEntity:AcDbMText
  ExtendedEntity (String) = (null)
  Linetype (String) = (null)
  EntityHandle (String) = 20000
  Text (String) = name_1
  Style = LABEL(f:"Arial",t:"name_1",s:1.5g,c:#000000)
  POINT (0 0 122)

OGRFeature(entities):1
  Layer (String) = 0
  SubClasses (String) = AcDbEntity:AcDbMText
  ExtendedEntity (String) = (null)
  Linetype (String) = (null)
  EntityHandle (String) = 20001
  Text (String) = name_2
  Style = LABEL(f:"Arial",t:"name_2",s:1.5g,c:#000000)
  POINT (1 1 222)

At least GDAL finds the label from DXF. You can also notice that point geometries were stored and XYZ. However, I do not know DXF and I am not sure if label is stored correctly. By opening the DXF file I could see that label tests are stored into MTEXT like here:

MTEXT
  5
20000
  8
0
100
AcDbEntity
100
AcDbMText
 40
1.5
  1
name_1
 10
0
 20
0
 30
122
  0
  • Unfortunately using that command did not populate labels. It also failed to generate "z" values for the points. Thank you though. – disconnected Jun 6 '16 at 21:47
  • Sorry, I was thinking that you were dealing with GPX :). I will find how to modify the command for DXF. – user30184 Jun 7 '16 at 5:04
  • ...Using your suggestion above I was able to create labels on the coordinates but not points. However this will work as a solution because I can run my .vrt and command to create points and yours to create labels and simply merge one DXF into the other. I tried to create multiple labels with points in one go but only received a litany of errors. P.S... I also upvoted your reply which is much appreciated but my upvote will not be visible until I have 15 reputation points. – disconnected Jun 8 '16 at 8:27

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