Layer Appearance

If a layers is listed in the Layer Panel in Pozi, but doesn’t appear correctly when turned on, the following issues may apply.

Rule-based or categorised styling doesn’t work

Layers that utilise rule-based or categorised styling may not display correctly in Pozi if the field that the rule or category relies upon is not available or the field name doesn’t match exactly.

  • Ensure that any field used for a rule or category is exposed via WFS (ie, not configured with ‘Do not expose via WFS’).
  • Ensure that name of the field used for a rule or category exactly matches the field name in the data. For example, if the rule specifies zone_code, but the field name in the data is actually ZONE_CODE, Pozi will not display the layer correctly. Update each rule or category in the layer’s style to use the correct field name.
Features are displayed with the wrong styling

When Pozi encounters a style that it doesn’t support, it will display the layer in a purple colour. (Subsequent layers with unsupported styles will display using different colours in order to remain visually distinct from each other.)

Simplify the style in the QGIS project and try again. For point features, replace custom point symbols with one of the standard symbols. For polygon features, replace hatch styles with semi-opaque fills or any of the supported fill styles.

Labels display the text ‘Placeholder’

If the label is configured using a text expression, Pozi will display a label of ‘Placeholder’. This text is generated by QGIS Server when

Text expressions are not supported directly in Pozi for styling or labelling. However you can create a virtual field using the text expression and then use the virtual field for your styling or labelling.

Labels are positioned incorrectly

A limitation for labels on vector features in Pozi is that labels are placed in the centre of the feature, regardless of any placement rules you’ve configured.

However you can apply a label offset by using a virtual field.

Features or highlights are mis-shaped

If a layer or highlight is mis-shaped, it’s possible that the layer is configured in QGIS with not enough precision.

  • WFS: Go to Project > Properties > QGIS Server > WFS/OAPIF > Geometry precision, and set it to 8 decimal places.
  • WMS: Go to Project > Properties > QGIS Server > WMS Capabilities > GetFeatureInfo geometry precision, and set it to 8 decimal places.
Selected features are not highlighted

WMS layers need to be configured in QGIS to include the feature’s geometry in the GetFeatureInfo response.

Go to Project > Properties > QGIS Server > WMS > Add geometry to feature response > tick ON

SVG or Font Awesome icons are not displayed

If you can see SVGs in QGIS but not in Pozi, it’s possible that the SVG Paths in QGIS are not configured correctly.

QGIS Server cannot render SVGs in WMS mode if the QGIS profile of the Pozi Service domain account is not configured with the correct SVG Paths.

Log in to the server as the Pozi Service user, launch QGIS, and ensure that the path to the Font Awesome SVGs is set to the correct location.

QGIS > Settings > Options > System > SVG Paths:

  • remove C:\Users\username\AppData\Roaming\QGIS\QGIS3\profiles\default\svg\
  • remove C:\OSGeo4W\apps\qgis-ltr\svg\
  • add C:\Pozi\QGIS Assets\Pozi SVGs

The paths that you remove will automatically be reinstated by QGIS under the new Pozi SVGs path, as is necessary for the correct configuration.

For further assistance, contact your Pozi support provider’s helpdesk.

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