dxf-reader: detection of dashed lines

[neumann]

In the example "fuaggeobau.dxf" (available to Frank), the detection of dashed lines is not working as expected.

The following element has LTYP 9, which is defined as dashed in the AcDbLinetypeTableRecord?. It would be good if this linetype could be exposed in the Style-String according to OGR Feature Styling.:

OGRFeature(entities):1964
  Layer (String) = 01311
  SubClasses (String) = AcDbEntity:AcDbPolyline
  ExtendedEntity (String) = { AV_EO_Linienele FID: 10749  {         0 } }
  Linetype (String) = LTYP9
  EntityHandle (String) = 3BA81
  Text (String) = (null)
  Style = PEN(c:#ffffff)
  LINESTRING : 6 points

[neumann]

The attached file shows the dashed line (left of the text label 508)

[warmerdam]

Currently the DXF driver does not attempt to read the line types table, nor deduce line patterns. I'm also not aware of any client applications utilizing the line patterns part of the OGR style specification so it would be hard to test correctness of translation.

The LTYPE table contains this excerpt describing the line style dot/dash pattern.

 72
    65
 73
     2
 40
0.17
 49
0.1
 74
     0
 49
-0.07
 74

I am going to defer activity on this for the time being. I'm not positive this is a good can of worms to open.