QgsVectorSimplifyMethod class
This class contains information how to simplify geometries fetched from a vector layer.
Contents
Public types
- enum SimplifyAlgorithm { Distance = 0, SnapToGrid = 1, Visvalingam = 2 }
- Types of local simplification algorithms that can be used.
- enum SimplifyHint { NoSimplification = 0, GeometrySimplification = 1, AntialiasingSimplification = 2, FullSimplification = 3 }
- Simplification flags for fast rendering of features.
Constructors, destructors, conversion operators
- QgsVectorSimplifyMethod()
- construct a default object
Public functions
- auto forceLocalOptimization() const -> bool
- Gets where the simplification executes, after fetch the geometries from provider, or when supported, in provider before fetch the geometries.
- auto maximumScale() const -> float
- Gets the maximum scale at which the layer should be simplified.
- void setForceLocalOptimization(bool localOptimization)
- Sets where the simplification executes, after fetch the geometries from provider, or when supported, in provider before fetch the geometries.
- void setMaximumScale(float maximumScale)
- Sets the maximum scale at which the layer should be simplified.
- void setSimplifyAlgorithm(SimplifyAlgorithm simplifyAlgorithm)
- Sets the local simplification algorithm of the vector layer managed.
- void setSimplifyHints(SimplifyHints simplifyHints)
- Sets the simplification hints of the vector layer managed.
- void setThreshold(float threshold)
- Sets the simplification threshold of the vector layer managed.
- void setTolerance(double tolerance)
- Sets the tolerance of simplification in map units. Represents the maximum distance in map units between two coordinates which can be considered equal.
- auto simplifyAlgorithm() const -> SimplifyAlgorithm
- Gets the local simplification algorithm of the vector layer managed.
- auto simplifyHints() const -> SimplifyHints
- Gets the simplification hints of the vector layer managed.
- auto threshold() const -> float
- Gets the simplification threshold of the vector layer managed.
- auto tolerance() const -> double
- Gets the tolerance of simplification in map units. Represents the maximum distance in map units between two coordinates which can be considered equal.
Enum documentation
enum QgsVectorSimplifyMethod::
Types of local simplification algorithms that can be used.
| Enumerators | |
|---|---|
| Distance |
The simplification uses the distance between points to remove duplicate points. |
| SnapToGrid |
The simplification uses a grid (similar to ST_SnapToGrid) to remove duplicate points. |
| Visvalingam |
The simplification gives each point in a line an importance weighting, so that least important points are removed first. |
enum QgsVectorSimplifyMethod::
Simplification flags for fast rendering of features.
| Enumerators | |
|---|---|
| NoSimplification |
No simplification can be applied. |
| GeometrySimplification |
The geometries can be simplified using the current map2pixel context state. |
| AntialiasingSimplification |
The geometries can be rendered with 'AntiAliasing' disabled because of it is '1-pixel size'. |
| FullSimplification |
All simplification hints can be applied ( Geometry + AA-disabling ) |