Class: QgsMapToPixelSimplifier¶
- class qgis.core.QgsMapToPixelSimplifier¶
Bases:
QgsAbstractGeometrySimplifier
Implementation of GeometrySimplifier using the “MapToPixel” algorithm
Simplifies a geometry removing points within of the maximum distance difference that defines the MapToPixel info of a RenderContext request. This class enables simplify the geometries to be rendered in a MapCanvas target to speed up the vector drawing.
QgsMapToPixelSimplifier(simplifyFlags: int, tolerance: float, simplifyAlgorithm: QgsMapToPixelSimplifier.SimplifyAlgorithm = QgsMapToPixelSimplifier.Distance) Constructor
QgsMapToPixelSimplifier(
QgsMapToPixelSimplifier
)Methods
Returns the squared 2D-distance of the vector defined by the two points specified
Returns whether the points belong to the same grid
Returns whether the envelope can be replaced by its BBOX when is applied the specified map2pixel context
Sets the local simplification algorithm of the vector layer managed
Sets the simplification hints of the vector layer managed
Sets the tolerance of the vector layer managed
- param geometry
Gets the local simplification algorithm of the vector layer managed
Gets the simplification hints of the vector layer managed
Attributes
- Distance = 0¶
- NoFlags = 0¶
- class SimplifyAlgorithm¶
Bases:
int
- SimplifyEnvelope = 2¶
- class SimplifyFlag¶
Bases:
int
- SimplifyGeometry = 1¶
- SnapToGrid = 1¶
- SnappedToGridGlobal = 3¶
- Visvalingam = 2¶
- calculateLengthSquared2D(x1: float, y1: float, x2: float, y2: float) float ¶
Returns the squared 2D-distance of the vector defined by the two points specified
- Parameters
x1 (float) –
y1 (float) –
x2 (float) –
y2 (float) –
- Return type
float
- equalSnapToGrid(x1: float, y1: float, x2: float, y2: float, gridOriginX: float, gridOriginY: float, gridInverseSizeXY: float) bool ¶
Returns whether the points belong to the same grid
- Parameters
x1 (float) –
y1 (float) –
x2 (float) –
y2 (float) –
gridOriginX (float) –
gridOriginY (float) –
gridInverseSizeXY (float) –
- Return type
bool
- isGeneralizableByMapBoundingBox(envelope: QgsRectangle, map2pixelTol: float) bool ¶
Returns whether the envelope can be replaced by its BBOX when is applied the specified map2pixel context
isGeneralizableByMapBoundingBox(self, envelope:
QgsRectangle
) -> bool Returns whether the envelope can be replaced by its BBOX when is applied the specified map2pixel context- Parameters
envelope (QgsRectangle) –
map2pixelTol (float) –
- Return type
bool
- setSimplifyAlgorithm(self, simplifyAlgorithm: QgsMapToPixelSimplifier.SimplifyAlgorithm)¶
Sets the local simplification algorithm of the vector layer managed
- Parameters
simplifyAlgorithm (QgsMapToPixelSimplifier.SimplifyAlgorithm) –
- setSimplifyFlags(self, simplifyFlags: int)¶
Sets the simplification hints of the vector layer managed
- Parameters
simplifyFlags (int) –
- setTolerance(self, value: float)¶
Sets the tolerance of the vector layer managed
- Parameters
value (float) –
- simplify(self, geometry: QgsGeometry) QgsGeometry ¶
- simplify(self, geometry: QgsAbstractGeometry) QgsAbstractGeometry
- Parameters
geometry (QgsGeometry) –
- Return type
- simplifyAlgorithm(self) QgsMapToPixelSimplifier.SimplifyAlgorithm ¶
Gets the local simplification algorithm of the vector layer managed
- Return type
- simplifyFlags(self) int ¶
Gets the simplification hints of the vector layer managed
- Return type
int