Class: QgsRasterTransparency¶
- class qgis.core.QgsRasterTransparency¶
Bases:
sip.wrapper
Defines the list of pixel values to be considered as transparent or semi transparent when rendering rasters.
QgsRasterTransparency() Constructor for QgsRasterTransparency.
QgsRasterTransparency(
QgsRasterTransparency
)Methods
Returns the transparency value for a single
value
pixel.Resets the transparency list to a single
value
.True if there are no entries in the pixel lists except the nodata value
Returns the opacity (as a value from 0 to 1) for a set of RGB pixel values.
Returns the opacity (as a value from 0 to 1) for a single
value
pixel.Reads the transparency information from an XML document.
Sets the transparent single value pixel list, replacing the whole existing list.
Sets the transparent three value pixel list, replacing the whole existing list.
Returns the transparent single value pixel list.
Returns the transparent three value pixel list.
Writes the transparency information to an XML document.
- class TransparentSingleValuePixel(minimum: float = 0, maximum: float = 0, opacity: float = 0, includeMinimum: bool = True, includeMaximum: bool = True)¶
Bases:
sip.wrapper
Constructor for TransparentSingleValuePixel.
- Parameters:
minimum – minimum pixel value to include in range
maximum – maximum pixel value to include in range
opacity – opacity for pixel, between 0 and 1.0
includeMinimum – whether the minimum value should be included in the range
includeMaximum – whether the maximum value should be included in the range
New in version 3.38.
QgsRasterTransparency.TransparentSingleValuePixel(QgsRasterTransparency.TransparentSingleValuePixel)
- includeMaximum¶
- includeMinimum¶
- max¶
- min¶
- opacity¶
- property percentTransparent¶
- class TransparentThreeValuePixel(red: float = 0, green: float = 0, blue: float = 0, opacity: float = 0)¶
Bases:
sip.wrapper
Constructor for TransparentThreeValuePixel.
- Parameters:
red – red pixel value
green – green pixel value
blue – blue pixel value
opacity – opacity for pixel, between 0 and 1.0
New in version 3.38.
QgsRasterTransparency.TransparentThreeValuePixel(QgsRasterTransparency.TransparentThreeValuePixel)
- blue¶
- green¶
- opacity¶
- property percentTransparent¶
- red¶
- alphaValue(self, value: float, globalTransparency: int = 255) int ¶
Returns the transparency value for a single
value
pixel.Searches through the transparency list, and if a match is found, the global transparency value is scaled by the stored transparency value.
- Parameters:
value (float) – the needle to search for in the transparency hay stack
globalTransparency (int = 255) – the overall transparency level for the layer
Deprecated since version use:
opacityForValue()
instead.alphaValue(self, redValue: float, greenValue: float, blueValue: float, globalTransparency: int = 255) -> int Returns the transparency value for a RGB pixel.
Searches through the transparency list, if a match is found, the global transparency value is scaled by the stored transparency value.
- Parameters:
redValue – the red portion of the needle to search for in the transparency hay stack
greenValue – the green portion of the needle to search for in the transparency hay stack
blueValue – the green portion of the needle to search for in the transparency hay stack
globalTransparency – the overall transparency level for the layer
Deprecated since version use:
opacityForRgbValues()
instead.- Return type:
int
- initializeTransparentPixelList(self, value: float)¶
Resets the transparency list to a single
value
.initializeTransparentPixelList(self, redValue: float, greenValue: float, blueValue: float) Resets the transparency list to single red, green, and blue values.
- Parameters:
value (float) –
- isEmpty(self) bool ¶
True if there are no entries in the pixel lists except the nodata value
- Return type:
bool
- opacityForRgbValues(self, redValue: float, greenValue: float, blueValue: float) float ¶
Returns the opacity (as a value from 0 to 1) for a set of RGB pixel values.
Searches through the transparency list, and if a match is found, returns the opacity corresponding to the values. Returns 1 if no matches are found.
If any of the red, green or blue values are NaN, 0 will be returned.
New in version 3.38.
- Parameters:
redValue (float) –
greenValue (float) –
blueValue (float) –
- Return type:
float
- opacityForValue(self, value: float) float ¶
Returns the opacity (as a value from 0 to 1) for a single
value
pixel.Searches through the transparency list, and if a match is found, returns the opacity corresponding to the value. Returns 1 if no matches are found.
New in version 3.38.
- Parameters:
value (float) –
- Return type:
float
- readXml(self, elem: QDomElement)¶
Reads the transparency information from an XML document.
- Parameters:
elem (QDomElement) –
- setTransparentSingleValuePixelList(self, newList: Iterable[QgsRasterTransparency.TransparentSingleValuePixel])¶
Sets the transparent single value pixel list, replacing the whole existing list.
See also
- Parameters:
newList (Iterable[QgsRasterTransparency.TransparentSingleValuePixel]) –
- setTransparentThreeValuePixelList(self, newList: Iterable[QgsRasterTransparency.TransparentThreeValuePixel])¶
Sets the transparent three value pixel list, replacing the whole existing list.
See also
- Parameters:
newList (Iterable[QgsRasterTransparency.TransparentThreeValuePixel]) –
- transparentSingleValuePixelList(self) List[QgsRasterTransparency.TransparentSingleValuePixel] ¶
Returns the transparent single value pixel list.
See also
- Return type:
- transparentThreeValuePixelList(self) List[QgsRasterTransparency.TransparentThreeValuePixel] ¶
Returns the transparent three value pixel list.
See also
- Return type:
- writeXml(self, doc: QDomDocument, parentElem: QDomElement)¶
Writes the transparency information to an XML document.
- Parameters:
doc (QDomDocument) –
parentElem (QDomElement) –