Also avoid massive long __repr__ strings for complex geometries,
as these can flood the Python console (and first aid plugin),
and aren't useful for debugging anyway.
Refs #14640
is called on non-single-line geometries
Previously we would just return an empty list when geometries of invalid
type were used, but this is dangerous and we are safer to explicitly
raise errors preventing use of asPolyline() with incompatible geometry types.
is called on non-single-point geometries
Previously we would just return QgsPointXY(0,0) when geometries of invalid
type were used, but this is dangerous and we are safer to explicitly
raise errors preventing use of asPoint() with incompatible geometry types.
Iterates over the geometries in the collection, allowing this type
of code:
gc = QgsGeometryCollection()
gc.fromWkt('GeometryCollection( Point(1 2), Point(11 12), LineString(33 34, 44 45))')
for part in gc:
print(part.asWkt())
- Calling removeGeometry with an invalid index will now raise an IndexError
- Calling collection[0] will return the first geometry in the collection,
collection[1] the second, etc. And negative indices return from the end
of the collection, so collection[-1] returns the last geometry in the collection.
- Geometries can be deleted by calling `del collection[1]` (deletes the
second geometry from the collection). Also supports negative indices
to count from the end of the collection.
- len(QgsCurve) returns number of points in curve
- raise IndexErrors when calling pointN, xAt, yAt, zAt, mAt, setXAt, setYAt,
setMAt, setZAt with invalid vertex indices
- Add [] getter for retrieving specific vertices, eg. ls[0] returns QgsPoint(...)
- Add [] setter for setting specific (existing) vertices, e.g. ls[1] = QgsPoint(1,2)
- Add del support for removing vertices, e.g. del ls[1] removes the second vertex
This allows easy iteration over all the parts of a geometry,
regardless of the geometry's type. E.g.
geometry = QgsGeometry.fromWkt( 'MultiPoint( 0 0, 1 1, 2 2)' )
for part in geometry.parts():
print(part.asWkt())
geometry = QgsGeometry.fromWkt( 'LineString( 0 0, 10 10 )' )
for part in geometry.parts():
print(part.asWkt())
There are two iterators available. QgsGeometry.parts() gives
a non-const iterator, allowing the parts to be modified in place:
geometry = QgsGeometry.fromWkt( 'MultiPoint( 0 0, 1 1, 2 2)' )
for part in geometry.parts():
part.transform(ct)
For a const iteration, calling .const_parts() gives a const
iterator, which cannot edit the parts but avoids a potentially expensive
QgsGeometry detach and clone
geometry = QgsGeometry.fromWkt( 'MultiPoint( 0 0, 1 1, 2 2)' )
for part in geometry.const_parts():
print(part.x())
All your uses of toUtf8().data() actually just need a const char*
So use constData() that is semantically more correct, and documented
to be faster.
From http://doc.qt.io/qt-5/qbytearray.html#data
"For read-only access, constData() is faster because it never
causes a deep copy to occur."
* make QgsWkbTypes a Q_GADGET and declare GeometryType as Q_ENUM
* include QObject
* remove extra include
* move QgsWkbTypes to moc headers
* run sip_include
Avoid conversion to/from WKB at OGR/QGIS side, and just directly
utilise OGR geometry API to construct QGIS geometries.
Shaves ~10% off rendering time for a large point layer (GPKG)
Because:
- Exactly follows curves and doesn't require segmentizing input geometry
- Also interpolates z/m values if they are present in input geometry
- Is faster
Returns a new curve representing a substring of a curve, from
a start distance and end distance.
If z or m values are present, the output z and m will be interpolated using
the existing vertices' z or m values.
Handles curved geometries without loss.
We never call this method using nullptrs, so there's no need
for this to be a pointer argument in the first place. And
having it a pointer encourages leaky code, such as the
leak this commit fixes in server.
