This changes the rendering of annotation frames to use QGIS' symbology
engine, which means that all the existing fill styles can now be
used to style annotation frames.
Also paint effects & data defined symbol parameters. Whee!
Not an ideal implementation (too much logic resides in the
gui QgsMapCanvasAnnotationItem class), but any approach
using current api will be dependant on some hacks.
Ideally we need a QgsVectorDataProvider method for finding
the closest feature(s) to a point(/line/polygon) within a
certain tolerance, with provider specific implementations
which offload this to the data store's spatial indices.
Then this handling could be bumped up to reside in
QgsAnnotation.
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.
This allows the CRS for map items to differ from the canvas/project
CRS. It also allows different map items to have different CRS,
eg an overview map can be set to a different CRS to the main map.
An unfortunate side effect of this change and the ongoing work
to separate compositions from canvas is that datum transforms
are no longer supported in composer. This cannot be fixed until
the datum transform store is rewritten to not depend on canvas
(ie, it's also broken for upcoming multi-canvas work)
The commit d44f1eba2fed18b3fef8d8865d79b3b6d8bc4d69 seems to break some WMS 1.3.0 client and WMS compliancy.
The commit d44f1eba2fed18b3fef8d8865d79b3b6d8bc4d69 has been written to fix an issue with QGIS WMS Client and to render image like other WMS Server.
This commit has been written to fix issue introduce by d44f1eba2fed18b3fef8d8865d79b3b6d8bc4d69.
It is based on MapServer code:
* https://github.com/mapserver/mapserver/blob/master/mapdraw.c#L115
* https://github.com/mapserver/mapserver/blob/master/HISTORY.TXT#L3768
And take account of axis invertion for output CRS.
