Before we had two checks - equals() and isGeosEqual() which
performed the exact same check (since equals() called the geos
equality test)
Since the geos equality test is a slow, topological test, which
considers two geometries equal if their component edges overlap,
but disregards ordering of vertices this is not always what we
want. There's also the issue that geos cannot consider m values
when testing the geometries, so two geometries with different
m values would be reported equal.
So, now calling QgsGeometry::equals performs a very fast, strict
equality test where geometries are only equal if the have exactly
the same vertices, type, and order.
And swap most code which was calling the slow geos test to instead
use the fast strict native test.
Removes duplicate nodes from the geometry, wherever removing the
nodes does not result in a degenerate geometry.
By default, z values are not considered when detecting duplicate
nodes. E.g. two nodes with the same x and y coordinate but
different z values will still be considered duplicate and one
will be removed. If useZValues is true, then the z values are
also tested and nodes with the same x and y but different z
will be maintained.
Note that duplicate nodes are not tested between different
parts of a multipart geometry. E.g. a multipoint geometry
with overlapping points will not be changed by this method.
The function will return true if nodes were removed, or false
if no duplicate nodes were found.
Includes unit tests and a processing algorithm which exposes
this functionality.
Now instead of mixing bools/numeric returns, we always use
ints, where:
-1 = left
0 = test failed, e.g. point on line
1 = right
Also fix a bunch of extra issues identified with left of tests
as a result of these changes
- QgsGeometry::fromPoint() was renamed to fromPointXY()
- QgsGeometry::fromMultiPoint() was renamed to fromMultiPointXY()
- QgsGeometry::fromMultiPolyline() was renamed to fromMultiPolylineXY()
- QgsGeometry::fromPolygon() was renamed to fromPolygonXY()
- QgsGeometry::fromMultiPolygon() was renamed to fromMultiPolygonXY()
Because feature.geometry().geometry() is confusing, and impossible
to search for in python code (e.g. is input.geometry() a QgsGeometry
or a QgsAbstractGeometry?)
But more importantantly: also add a const version
QgsGeometry::constGet(). The non-const
version is slow, since it now forces a detach to avoid corrupting
geometries (since QgsGeometry is shared, it's not safe to directly
access its primitive QgsAbstractGeometry and start messing with
it without first detaching). This is a big risk in the 2.x API
which could potentially corrupt feature geometries with unexpected
outcomes.
Update all uses to constGet where possible.
By moving logic to abstract geometry subclasses so that they
can trivially retrieve the vertex number, instead of relying
on the inefficient coordinateSequence method.
Has flow on speed boosts to many geometry operations like
calculation of closest points in a geometry, which will
benefit snapping related operations.
and add new QgsGeometry::fromPolyline which uses QgsPoint
We want to encourage people not to use the QgsPointXY method, as it drops
Z/M values. So it's moved across to a different name to make way
for a new QgsGeometry::fromPolyline which uses a QgsPoint list
instead of QgsPointXY, thus keeping Z/M values intact.
Similarly, QgsPolyline now is a list of QgsPoint (keeping z/m values)
and the old 2d QgsPolyline type was renamed to QgsPolylineXY.
Making the QgsPoint method the "preferred" method and making linestrings
just as easy to create from z/m dimensioned points as 2d points is
important to push people to write code which does not discard
these important dimensions.
As a bonus, the QgsPoint methods are more efficient anyway, since
they don't require creation of a temporary list.
Introducing:
1. STL-style iterator: QgsAbstractGeometry::vertex_iterator
2. Java-style iterator: QgsVertexIterator (built on top of STL-style)
The iterators are modeled after Qt's STL-style and Java-style iterators,
the idea is to replace nextVertex() method and later introduce iterators
for other bits (e.g. part_iterator, ring_iterator).
Instead move it to a private QgsGeometry member. It's copied
with QgsGeometry, but not the underlying private geometry
data.
This means the error string can be changed without detaching
(and copying) the geometry data.
Also make greater use of error string for all use of GEOS
functions.
When methods are called that use GEOS to create new geometries, the
result geometries now contain information about what has gone wrong in
case of an error.
In practice, this means it's possible to give more detailed information
in place (and not only in the message log) when things like processing
algorithms fail.
Subdivides the geometry. The returned geometry will be a collection
containing subdivided parts from the original geometry, where no
part has more then the specified maximum number of nodes.
Geometries are passed as const reference and returned by value.
This make using the API easier and reduces the risk of ownership
problems.
The overhead is minimal due to implicit sharing.
Fix https://github.com/qgis/qgis3.0_api/issues/68
Previously this was always read from settings when using
QgsGeometryValidator. It's now an explicit argument
when constructing QgsGeometryValidator or calling the
static validation methods, allowing choice of internal/GEOS
validation methods.
Helps remove more QgsSettings use from core.
