This is necessary in order to be able to correctly translate between absolute and relative paths
deeper in the code - e.g. paths to SVG files used in marker or fill symbols.
Until now, relative paths were translated to absolute paths on the fly.
This is now changed - paths to files should be always absolute within QGIS objects - and paths
only get turned into relative when saving projects. When loading a project, relative paths
are translated to absolute paths immediately.
This should lower the overall confusion about relative/absolute paths within QGIS, and also
allow having different base directories for relative paths (e.g. QML or QPT files may use relative paths
to their directory - rather than to the project directory)
This commit implements a new QgsAnnotationManager class, which
handles storage, writing and retrieval of annotations.
QgsProject has an annotationManager() attached to it. Map canvases
sync their visible QgsMapCanvasAnnotationItems to the annotations
contained within the project's annotation manager.
This moves all management, storage and retrieval of annotations
up to core and out of app/canvas.
Splits the rendering component of annotations out from map
canvas item component.
A new core abstract base class QgsAnnotation handles the
management of the common properties associated with an
annotation, and handles rendering the annotation onto a
QgsRenderContext destination.
Existing annotation classes have been ported to this, and
with the exception of the form annotation moved into core.
Form annotations are dependant on editor widgets and must
remain in GUI.
A new QgsMapCanvasAnnotationItem item class implements
a QgsMapCanvasItem which draws an annotation inside the
canvas, and handles synchronising the position and size
of the canvas item with the QgsAnnotation position/size.
This allows annotations to be safely used in a multi-canvas
environment, with a single QgsAnnotation being displayed
in multiple canvases (even if the canvases have different
extent/crs/etc).
Additionally it allows annotations to be directly rendered
to a map (eg in composer) without going through the
gui based Qt graphics scene framework.
Also removes lots of duplicate code, and adds some basic
unit tests for annotations.
