/************************************************************************ * This file has been generated automatically from * * * * src/core/qgsmaplayerrenderer.h * * * * Do not edit manually ! Edit header and run scripts/sipify.py again * ************************************************************************/ class QgsMapLayerRenderer { %Docstring(signature="appended") Base class for utility classes that encapsulate information necessary for rendering of map layers. The rendering is typically done in a background thread, so it is necessary to keep all structures required for rendering away from the original map layer because it may change any time. Because the data needs to be copied (to avoid the need for locking), it is highly desirable to use copy-on-write where possible. This way, the overhead of copying (both memory and CPU) will be kept low. Qt containers and various Qt classes use implicit sharing. The scenario will be: 1. renderer job (doing preparation in the GUI thread) calls :py:func:`QgsMapLayer.createMapRenderer()` and gets instance of this class. The instance is initialized at that point and should not need additional calls to :py:class:`QgsVectorLayer`. 2. renderer job (still in GUI thread) stores the renderer for later use. 3. renderer job (in worker thread) calls :py:func:`QgsMapLayerRenderer.render()` 4. renderer job (again in GUI thread) will check :py:func:`~errors` and report them %End %TypeHeaderCode #include "qgsmaplayerrenderer.h" %End public: QgsMapLayerRenderer( const QString &layerID, QgsRenderContext *context = 0 ); %Docstring Constructor for QgsMapLayerRenderer, with the associated ``layerID`` and render ``context``. %End virtual ~QgsMapLayerRenderer(); virtual bool render() = 0; %Docstring Do the rendering (based on data stored in the class). Returns ``True`` if the layer was completely rendered successfully (i.e. the render was not canceled early). %End virtual bool forceRasterRender() const; %Docstring Returns ``True`` if the renderer must be rendered to a raster paint device (e.g. QImage). Some layer settings require layers to be effectively "flattened" while rendering maps, which is achieved by first rendering the layer onto a raster paint device and then compositing the resultant image onto the final map render. E.g. if a layer contains features with transparency or alternative blending modes, and the effects of these opacity or blending modes should be restricted to only affect other features within the SAME layer, then a flattened raster based render is required. Subclasses should return ``True`` whenever their corresponding layer settings require the layer to always be rendered using a raster paint device. .. versionadded:: 3.18 %End virtual Qgis::MapLayerRendererFlags flags() const; %Docstring Returns flags which control how the map layer rendering behaves. .. versionadded:: 3.34 %End virtual QgsFeedback *feedback() const; %Docstring Access to feedback object of the layer renderer (may be ``None``) %End QStringList errors() const; %Docstring Returns list of errors (problems) that happened during the rendering %End QString layerId() const; %Docstring Gets access to the ID of the layer rendered by this class %End QgsRenderContext *renderContext(); %Docstring Returns the render context associated with the renderer. .. versionadded:: 3.10 %End bool isReadyToCompose() const; %Docstring Returns whether the renderer has already drawn (at least partially) some data .. versionadded:: 3.18 %End QList< QgsRenderedItemDetails * > takeRenderedItemDetails() /TransferBack/; %Docstring Takes the list of rendered item details from the renderer. Ownership of items is transferred to the caller. .. seealso:: :py:func:`appendRenderedItemDetails` .. versionadded:: 3.22 %End protected: void appendRenderedItemDetails( QgsRenderedItemDetails *details /Transfer/ ); %Docstring Appends the ``details`` of a rendered item to the renderer. Rendered item details can be retrieved by calling :py:func:`~QgsMapLayerRenderer.takeRenderedItemDetails`. Ownership of ``details`` is transferred to the renderer. .. seealso:: :py:func:`takeRenderedItemDetails` .. versionadded:: 3.22 %End }; /************************************************************************ * This file has been generated automatically from * * * * src/core/qgsmaplayerrenderer.h * * * * Do not edit manually ! Edit header and run scripts/sipify.py again * ************************************************************************/