A port of the equivalent method from GEOS, but with added support
for curved geometries and M values
Reorganizes the geometry into a normalized form (or "canonical" form).
Polygon rings will be rearranged so that their starting vertex is
the lower left and ring orientation follows the right hand rule, collections
are ordered by geometry type, and other normalization techniques are applied.
The resultant geometry will be geometrically equivalent to the original geometry.
Allows for comparison of geometry objects, e.g. to allow for stable
sorting of them.
Ported from the GEOS equivalent method, but with addition of support
for M values and curved geometry types
to transform the vertices of a QgsAbstractGeometry
E.g.
class Transformer(QgsAbstractGeometryTransformer):
def transformPoint(self, x, y, z, m):
return True, x * 2, y + 1, z, m
transformer = Transformer()
g = QgsGeometry.fromWkt('LineString(3 0, 10 0, 10 10)')
g.get().transform(transformer)
print(g.asWkt()) # 'LineString (6 1, 20 1, 20 11)'
* Add measurement tool bar.
* Add class for measure line.
* Get coordinate of clicked point.
* Add clicked point to string line.
* Store clicekd points to layer.
* Try to render the measurement line.
* Render the measurement line (with some problems).
* Store points in vector.
* Make identify and measure tool exlusive to each other.
* Add measurement dialog.
* Fix only one action must active.
* Some code suggestion from Martin.
* Revert code to show the line.
* Show segment length and the total.
* Implement close dialog means restart 3d measurement.
* Add new button.
* Add unit combo box.
* Fix shadowing private member of class.
* Add slot to combo box unit changes.
* Hide ellipsoid and cartesian radio button.
* Add measure line for QgsPoint.
* Add unit changes feature.
* Add help (pointed to 2D measurement tool).
* Add finish measurement using right click.
* Remove keypress event, it does not make sense.
* Add remove-last-point with middle button.
* Add crsChanged event.
* Remove confusing tooltip.
* Add pan (camera control) action tool for clear state of 3d map tool.
* Change 3D identify tool cursor.
* Fix distance 2D to 3D.
* Remove unclear method.
* Add unit test for measureLine3D.
* Add 3D measurement setting.
* Add header.
* Make extra 3D renderers refresh the scene when they are updated
+ update the 3D renderer every time the measurement line layer is modified
* Set Altitude clamping to absolute.
* Remove options for 3D measurement line.
* Remove help button in 3D measurement dialog.
* Merge duplicate code for handle clicked position.
* Use color for 3d measure line from 2d one.
* Remove unneeded reimplementation method.
* Remove 2D canvas reference.
* Unify update measurement layer.
Use local variable for feature and line
* Create measurement layer once.
* Use data provider to change the geometry.
* Add length3D for QgsLineString.
* Simplify distance calculation and presentation. Remove QgsDistanceArea measurement.
* Descaled z value based on the terrain vertical scale.
* Remove line when tool is deactivated.
* Enable changing the line color from setting, but after re-activation.
* Update color of measurement line after saving option.
* Remove debug message.
* Remove 3D length calculation from distancearea.
* Handle 2D case for length3D, more unit test, and docstring.
* Fix typos.
* Addressing Martin's and Nyall's review.
* Remove setMeasurement to avoid confussion.
... you are too slow and QJson API is so ugly.
Now using this wonderful json lib:
https://github.com/nlohmann/json
Results in release mode (QJson tests are not shown but
QJson was even slower than string concat).
PASS : TestQgsJsonUtils::testExportAttributesJson(Use json)
RESULT : TestQgsJsonUtils::testExportAttributesJson():"Use json":
0.0022 msecs per iteration (total: 75, iterations: 32768)
PASS : TestQgsJsonUtils::testExportAttributesJson(Use old string concat)
RESULT : TestQgsJsonUtils::testExportAttributesJson():"Use old string concat":
0.0032 msecs per iteration (total: 54, iterations: 16384)
PASS : TestQgsJsonUtils::testExportFeatureJson(Use json)
RESULT : TestQgsJsonUtils::testExportFeatureJson():"Use json":
0.011 msecs per iteration (total: 96, iterations: 8192)
PASS : TestQgsJsonUtils::testExportFeatureJson(Use old string concat)
RESULT : TestQgsJsonUtils::testExportFeatureJson():"Use old string concat":
0.015 msecs per iteration (total: 64, iterations: 4096)
PASS : TestQgsJsonUtils::testExportGeomToJson(Use json)
RESULT : TestQgsJsonUtils::testExportGeomToJson():"Use json":
0.76 msecs per iteration (total: 98, iterations: 128)
PASS : TestQgsJsonUtils::testExportGeomToJson(Use old string concat)
RESULT : TestQgsJsonUtils::testExportGeomToJson():"Use old string concat":
0.85 msecs per iteration (total: 55, iterations: 64)
PASS : TestQgsJsonUtils::cleanupTestCase()
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
- 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
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."
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.
Checks whether a function declaration has parameters that are
top level const.
const values in declarations do not affect the signature of a
function, so they should not be put there.
