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INSPIRE Community Forum

Points or Pixel - Align definition of style description units?

While working on the ELF Cadastre in the ELF project the analysis of the  INSPIRE data specifications for CP and BU revealed that different style description units are used:

CP DS defines the outline in pixels: parcel 1 pixel and zoning 2 pixels while BU DS defines outline in points: building part 0.2 pt and building 0.4 pt.

If we consider the representation of cadastral parcel, 1 pixel as the minimun size of drawing on screen, the building should be thinnest (not possible) or change the colour from black to grey (Image2_Grey), or another possibility should be to draw building with the fill color only (default) without outline but with this option we lose the building part (image3_without_outline)

Also the representation of underground buildings is not well defined.

The ELF project proposes to harmonise the style description units for easier implementation and to revise the representation of underground buildings.

  • Dominique LAURENT

    By Dominique LAURENT

    It's a good idea to harmonise the way portrayal rules are defined and especially to adopt a common unit (pixel or point) to define the thickness of a symbol. As far as I can remember, in theme BU, we had moved from pixels to points because lines defined with pixels were too thick ... but I do't think we had checked if using "points" as uom was allowed by the standard and how it worked.

    Good representation of underground buildings was not an objective of TWG BU; the idea was to use simple portrayal rules, using only the mandatory attributes (and number of floors above or under ground is  voidable information). But it may be a good idea to propose it for INSPIRE as additional legend.