Project Configuration

A QGIS project is a collection of layers and settings that make up a QGIS map. Pozi uses these projects as layer catalogues, each of which is displayed in Pozi as a layer group.

Project Creation

Create new project from scratch:

1. open QGIS
2. Project > Save > specify name and path of new project file (.qgs)
3. note the exact file path of project file (needed for project registration below)

Project Organization

Keep your QGIS project files and source data organised on the server. Use consistent naming conventions for project files, folders, and database tables to make ongoing maintenance easier.

Default Styles

By default, any new layers you add to your QGIS project display with an opacity of 100%. This prevents users from seeing important information from underlying layers if they are covered by fully opaque polygon features. To avoid this, set the project’s default opacity to 50%.

Project > Properties > Styles > Options > Opacity > set to 50%

Basemap

It’s useful to include a basemap in the project to provide visual context for the layers you will add on top.

Ensure that you exclude the basemap from WMS to prevent it appearing in Pozi. See Exclude Layers for more information.

Layer Ordering

Layers at the top of the QGIS Layers panel draw above the layers below them. Order layers logically so that contextual or background content sits underneath the operational layers that users need to interact with.

Layer Grouping

Group related layers together in QGIS to help users find what they need more easily. This grouping is reflected in Pozi’s layer control.

Web Services

Settings

Project > Properties > QGIS Server > WMS

• Exclude layers (tick) > add > pick any layers such as basemaps that you don’t need to publish in Pozi
• Use layer ids as names: ensure this is NOT ticked
• Add geometry to feature response: tick ON

Profiles

Pozi “profiles” are a way to present separate streamlined views of your organisation’s layers for a variety of workflows. Users can switch between profiles using the dropdown menu in the layer panel to see a filtered view of all the available layers and search options. Profiles enable users to view a subset of layers for a given task at hand, and to switch profiles to view other layers for which they have been granted permissions.

Any given map catalogue can be assigned zero or one or more profile names in the QGIS project using a keyword parameter. If Pozi is launched with a profile parameter in the URL (eg ../#/profile[assets]/), or if the user picks a profile from the dropdown menu at the top of the layer panel, Pozi will display only those catalogues that have been configured with that profile name.

The profiles keyword is defined at the catalogue level (ie, not layer level). When Pozi loads the catalogue, it checks for the presence of any profile keywords. If any profiles are found, Pozi adds a dropdown menu at the top of the layer panel listing each available profile.

Project > Properties > QGIS Server > Services Capabilities > Keyword list

Example: profiles=Assets;Infrastructure

(When assigning multiple profiles, separate the profile names with a semicolons.)

Performance Testing

A fast map is a usable map.

The speed at which Pozi can access layers from the QGIS project is limited by how fast QGIS Server can access the layers from their respective data sources.

A slow QGIS project is often a strong indicator that QGIS Server will also take longer to read the project and publish its catalogue to Pozi.

To ensure that QGIS Server is able to access the layers quickly, check the project’s performance using QGIS’s debugging tool to identify any performance issues.

View > Panels > Debugging/Development Tools > Profiler (clock button)

The profiler is useful in two main ways:

• Project Load helps identify layers or data sources that make the project slow to open.
• Map Rendering, where available in your QGIS version, helps identify layers that are expensive to redraw when panning or zooming.

As soon as you load your QGIS project, a new category called Project Load will be available. Select it from the category list.

Expand the entry called Reading map layers in the profiler tree to see all of the QGIS project layers and their corresponding loading time.

If the results show any layer that takes more than a fraction of a second to load, there may be an issue with the network or database that is worth investigating.

Common improvements to consider include:

• Use suitable data formats. Large local GeoJSON files can be inefficient for QGIS projects, while GeoPackage, SHP, or TAB may load more efficiently in some cases.
• Apply scale dependencies where appropriate so detailed layers only render when users are zoomed in to a suitable level.
• Keep layer CRSs consistent where practical to reduce the overhead of on-the-fly reprojection.
• Ensure layers are spatially indexed where the source format or database supports it.
• Keep data close to QGIS Server where possible. Data stored on slow network locations may take longer to load than the same data stored locally or on faster infrastructure.
• Keep the active project manageable by removing obsolete, duplicate, archived, or low-value layers, and by consolidating related layers where that simplifies the catalogue. Very large projects are often harder to maintain and slower to load.

If your project relies heavily on SQL Server and remains slow after the usual optimisation steps, QGIS metadata-based optimisation may also help reduce project load times. See SQL Server.

For optional further reading, see the Pozi Community discussion Optimising a QGIS Project (available to Pozi Community members only).

Registration

Contact your Pozi support provider’s helpdesk to request for the new QGIS project to be added to your Pozi site.