Python core.QgsSymbolLayerV2Utils類代碼示例

 def _getSymbolWidth(self, context, width, unit):
     scale = 1.0
     if unit == QgsSymbolV2.MapUnit:
         scale = QgsSymbolLayerV2Utils.lineWidthScaleFactor(
             context, QgsSymbolV2.MM) / QgsSymbolLayerV2Utils.lineWidthScaleFactor(context, QgsSymbolV2.MapUnit)
     width = max(width + 2 * self._buffer * scale, self._minWidth * scale)
     return width

    def testMapUnitScaleFactor(self):
        # test QgsSymbolLayerV2Utils::mapUnitScaleFactor() using QgsMapUnitScale

        ms = QgsMapSettings()
        ms.setExtent(QgsRectangle(0, 0, 100, 100))
        ms.setOutputSize(QSize(100, 50))
        ms.setOutputDpi(300)
        r = QgsRenderContext.fromMapSettings(ms)

        # renderer scale should be about 1:291937841

        c = QgsMapUnitScale()
        sf = QgsSymbolLayerV2Utils.mapUnitScaleFactor(r, QgsSymbolV2.MapUnit, c)
        self.assertAlmostEqual(sf, 1.0, places=5)
        sf = QgsSymbolLayerV2Utils.mapUnitScaleFactor(r, QgsSymbolV2.MM, c)
        self.assertAlmostEqual(sf, 23.622047, places=5)
        sf = QgsSymbolLayerV2Utils.mapUnitScaleFactor(r, QgsSymbolV2.Pixel, c)
        self.assertAlmostEqual(sf, 2.0, places=5)

def set_alpha(values, feature, parent):
    """
        Sets the alpha component of a color
        
        <p><h4>Syntax</h4>
        set_alpha(<i>color</i>, <i>alpha</i>)</p>

        <p><h4>Arguments</h4>
        <i>  color</i> &rarr; a color<br>
        <i>  alpha</i> &rarr; an alpha value between 0 and 255<br></p>
        
        <p><h4>Example</h4>
        <!-- Show example of function.-->
             set_alpha('255,255,255,255', 125) &rarr; '255,255,255,125'</p>
    """
    try:
        color = QgsSymbolLayerV2Utils.decodeColor(values[0])
        color.setAlpha(values[1])
        return QgsSymbolLayerV2Utils.encodeColor(color)
    except:
        return None

def set_hsv_value(values, feature, parent):
    """
        Sets the value of a color
        
        <p><h4>Syntax</h4>
        set_hsv_value(<i>color</i>, <i>value</i>)</p>

        <p><h4>Arguments</h4>
        <i>  color</i> &rarr; a color<br>
        <i>  value</i> &rarr; a integer between 0 and 100<br></p>
        
        <p><h4>Example</h4>
        <!-- Show example of function.-->
             set_hsv_value('0,255,0,255', 50) &rarr; '0,128,0,255'</p>
    """
    try:
        color = QgsSymbolLayerV2Utils.decodeColor(values[0])
        color.setHsvF(color.hueF(), color.saturationF(), values[1] / 100.0, color.alphaF())
        return QgsSymbolLayerV2Utils.encodeColor(color)
    except:
        return None

def set_hue(values, feature, parent):
    """
        Sets the hue component of a color
        
        <p><h4>Syntax</h4>
        set_hue(<i>color</i>, <i>hue</i>)</p>

        <p><h4>Arguments</h4>
        <i>  color</i> &rarr; a color<br>
        <i>  hue</i> &rarr; a integer between 0 and 360<br></p>
        
        <p><h4>Example</h4>
        <!-- Show example of function.-->
             set_hue('0,255,0,255', 0) &rarr; '255,0,0,255'</p>
    """
    try:
        color = QgsSymbolLayerV2Utils.decodeColor(values[0])
        color.setHslF(values[1] / 360.0, color.saturationF(), color.lightnessF(), color.alphaF())
        return QgsSymbolLayerV2Utils.encodeColor(color)
    except:
        return None

 def toDomElement(self, domDocument):
     """
     Returns a QDomElement with the object instance settings
     """
     spColumnElement = domDocument.createElement("SpatialField")
     spColumnElement.setAttribute("name",self._spatialField)
     spColumnElement.setAttribute("labelField",self._labelField)
     spColumnElement.setAttribute("itemid",self._itemId)
     spColumnElement.setAttribute("srid",self._srid)
     spColumnElement.setAttribute("geomType",self._geomType)
     spColumnElement.setAttribute("zoom",self._zoom_level)
     symbolElement = domDocument.createElement("Symbol")
     
     #Append symbol properties element
     if not self._symbol is None:
         prop = self._symbol.properties()
         QgsSymbolLayerV2Utils.saveProperties(prop,domDocument,symbolElement)
         symbolElement.setAttribute("layerType",self._layerType)
     
     spColumnElement.appendChild(symbolElement)
     
     return spColumnElement

    def testConvertToPainterUnits(self):
        # test QgsSymbolLayerV2Utils::convertToPainterUnits() using QgsMapUnitScale

        ms = QgsMapSettings()
        ms.setExtent(QgsRectangle(0, 0, 100, 100))
        ms.setOutputSize(QSize(100, 50))
        ms.setOutputDpi(300)
        r = QgsRenderContext.fromMapSettings(ms)

        # renderer scale should be about 1:291937841

        # start with no min/max scale
        c = QgsMapUnitScale()

        size = QgsSymbolLayerV2Utils.convertToPainterUnits(r, 2, QgsSymbolV2.MapUnit, c)
        self.assertAlmostEqual(size, 1.0, places=5)
        size = QgsSymbolLayerV2Utils.convertToPainterUnits(r, 2, QgsSymbolV2.MM, c)
        self.assertAlmostEqual(size, 23.622047, places=5)
        size = QgsSymbolLayerV2Utils.convertToPainterUnits(r, 2, QgsSymbolV2.Pixel, c)
        self.assertAlmostEqual(size, 2.0, places=5)

        # minimum size greater than the calculated size, so size should be limited to minSizeMM
        c.minSizeMM = 5
        c.minSizeMMEnabled = True
        size = QgsSymbolLayerV2Utils.convertToPainterUnits(r, 2, QgsSymbolV2.MapUnit, c)
        self.assertAlmostEqual(size, 59.0551181, places=5)
        # only conversion from mapunits should be affected
        size = QgsSymbolLayerV2Utils.convertToPainterUnits(r, 2, QgsSymbolV2.MM, c)
        self.assertAlmostEqual(size, 23.622047, places=5)
        size = QgsSymbolLayerV2Utils.convertToPainterUnits(r, 2, QgsSymbolV2.Pixel, c)
        self.assertAlmostEqual(size, 2.0, places=5)
        c.minSizeMMEnabled = False

        # maximum size less than the calculated size, so size should be limited to maxSizeMM
        c.maxSizeMM = 0.1
        c.maxSizeMMEnabled = True
        size = QgsSymbolLayerV2Utils.convertToPainterUnits(r, 2, QgsSymbolV2.MapUnit, c)
        self.assertAlmostEqual(size, 1.0, places=5)
        # only conversion from mapunits should be affected
        size = QgsSymbolLayerV2Utils.convertToPainterUnits(r, 2, QgsSymbolV2.MM, c)
        self.assertAlmostEqual(size, 23.622047, places=5)
        size = QgsSymbolLayerV2Utils.convertToPainterUnits(r, 2, QgsSymbolV2.Pixel, c)
        self.assertAlmostEqual(size, 2.0, places=5)

    def testPixelSizeScaleFactor(self):
        # test QgsSymbolLayerV2Utils::pixelSizeScaleFactor() using QgsMapUnitScale

        ms = QgsMapSettings()
        ms.setExtent(QgsRectangle(0, 0, 100, 100))
        ms.setOutputSize(QSize(100, 50))
        ms.setOutputDpi(300)
        r = QgsRenderContext.fromMapSettings(ms)

        # renderer scale should be about 1:291937841

        # start with no min/max scale
        c = QgsMapUnitScale()

        sf = QgsSymbolLayerV2Utils.pixelSizeScaleFactor(r, QgsSymbolV2.MapUnit, c)
        self.assertAlmostEqual(sf, 0.5, places=5)
        sf = QgsSymbolLayerV2Utils.pixelSizeScaleFactor(r, QgsSymbolV2.MM, c)
        self.assertAlmostEqual(sf, 11.8110236, places=5)
        sf = QgsSymbolLayerV2Utils.pixelSizeScaleFactor(r, QgsSymbolV2.Pixel, c)
        self.assertAlmostEqual(sf, 1.0, places=5)

        # minimum scale greater than the renderer scale, so should be limited to minScale
        c.minScale = 1 / 150000000.0
        sf = QgsSymbolLayerV2Utils.pixelSizeScaleFactor(r, QgsSymbolV2.MapUnit, c)
        self.assertAlmostEqual(sf, 3.8925045, places=5)
        # only conversion from mapunits should be affected
        sf = QgsSymbolLayerV2Utils.pixelSizeScaleFactor(r, QgsSymbolV2.MM, c)
        self.assertAlmostEqual(sf, 11.811023, places=5)
        sf = QgsSymbolLayerV2Utils.pixelSizeScaleFactor(r, QgsSymbolV2.Pixel, c)
        self.assertAlmostEqual(sf, 1.0, places=5)
        c.minScale = 0

        # maximum scale less than the renderer scale, so should be limited to maxScale
        c.maxScale = 1 / 350000000.0
        sf = QgsSymbolLayerV2Utils.pixelSizeScaleFactor(r, QgsSymbolV2.MapUnit, c)
        self.assertAlmostEqual(sf, 0.5, places=5)
        # only conversion from mapunits should be affected
        sf = QgsSymbolLayerV2Utils.pixelSizeScaleFactor(r, QgsSymbolV2.MM, c)
        self.assertAlmostEqual(sf, 11.8110236, places=5)
        sf = QgsSymbolLayerV2Utils.pixelSizeScaleFactor(r, QgsSymbolV2.Pixel, c)
        self.assertAlmostEqual(sf, 1.0, places=5)

    def testEncodeDecode(self):
        # test encoding and decoding QgsMapUnitScale

        s = QgsMapUnitScale()
        s.minScale = 50
        s.maxScale = 100
        s.minSizeMMEnabled = True
        s.minSizeMM = 3
        s.maxSizeMMEnabled = False
        s.maxSizeMM = 99

        encode = QgsSymbolLayerV2Utils.encodeMapUnitScale(s)
        r = QgsSymbolLayerV2Utils.decodeMapUnitScale(encode)
        self.assertEqual(s, r)

        # check old style encoding
        encode = '9,78.3'
        r = QgsSymbolLayerV2Utils.decodeMapUnitScale(encode)
        self.assertEqual(r.minScale, 9)
        self.assertEqual(r.maxScale, 78.3)
        self.assertFalse(r.minSizeMMEnabled)
        self.assertEqual(r.minSizeMM, 0)
        self.assertFalse(r.maxSizeMMEnabled)
        self.assertEqual(r.maxSizeMM, 0)

    def create(dom_document):
        """
        Create an instance of the 'SpatialFieldsConfiguration' object from a DOM document.
        Returns None if the dom_document is invalid.
        """
        from stdm.ui.composer import SpatialFieldMapping
        
        dataSourceElem = dom_document.documentElement().firstChildElement("DataSource")
        
        if dataSourceElem == None:
            return None
        
        spatialFieldsConfigElement = dataSourceElem.firstChildElement("SpatialFields") 
        spFieldsConfig = SpatialFieldsConfiguration()
        
        #Get spatial field mappings
        spatialFieldMappingList = spatialFieldsConfigElement.elementsByTagName("SpatialField")
        numItems = spatialFieldMappingList.length()
        
        for i in range(numItems):
            spatialFieldMappingElement = spatialFieldMappingList.item(i).toElement()
            labelField = spatialFieldMappingElement.attribute("labelField")
            spatialField = spatialFieldMappingElement.attribute("name")
            itemId = spatialFieldMappingElement.attribute("itemid") 
            srid = int(spatialFieldMappingElement.attribute("srid"))
            geomType = spatialFieldMappingElement.attribute("geomType") 
            zoom = float(spatialFieldMappingElement.attribute("zoom"))
            zoom_type = spatialFieldMappingElement.attribute('zoomType', 'RELATIVE')
            
            #Create spatial field mapping
            spFieldMapping = SpatialFieldMapping(spatialField,labelField) 
            spFieldMapping.setItemId(itemId)
            spFieldMapping.setSRID(srid)
            spFieldMapping.setGeometryType(geomType)
            spFieldMapping.setZoomLevel(zoom)
            spFieldMapping.zoom_type = zoom_type

            symbolElement = spatialFieldMappingElement.firstChildElement("Symbol")
            if not symbolElement is None:
                layerType = symbolElement.attribute("layerType")
                layerProps = QgsSymbolLayerV2Utils.parseProperties(symbolElement)
                symbolLayer =  QgsSymbolLayerV2Registry.instance().createSymbolLayer(layerType,layerProps)
                spFieldMapping.setSymbolLayer(symbolLayer)
            
            spFieldsConfig.addSpatialFieldMapping(spFieldMapping)
            
        return spFieldsConfig

def blue(values, feature, parent):
    """
        Returns the blue component of a color
        
        <p><h4>Syntax</h4>
        blue(<i>color</i>)</p>

        <p><h4>Arguments</h4>
        <i>  color</i> &rarr; a color<br></p>
        
        <p><h4>Example</h4>
        <!-- Show example of function.-->
             blue('0,0,255') &rarr; 255</p>
    """
    try:
        return QgsSymbolLayerV2Utils.decodeColor(values[0]).blue()
    except:
        return None

def alpha(values, feature, parent):
    """
        Returns the alpha component of a color
        
        <p><h4>Syntax</h4>
        alpha(<i>color</i>)</p>

        <p><h4>Arguments</h4>
        <i>  color</i> &rarr; a color<br></p>
        
        <p><h4>Example</h4>
        <!-- Show example of function.-->
             alpha('255,255,255,125') &rarr; 125</p>
    """
    try:
        return QgsSymbolLayerV2Utils.decodeColor(values[0]).alpha()
    except:
        return None

def hsv_value(values, feature, parent):
    """
        Returns the hsv value component of a color, an integer between 0-100
        
        <p><h4>Syntax</h4>
        hsv_value(<i>color</i>)</p>

        <p><h4>Arguments</h4>
        <i>  color</i> &rarr; a color<br></p>
        
        <p><h4>Example</h4>
        <!-- Show example of function.-->
             hsv_value('125,255,125') &rarr; 100</p>
    """
    try:
        # Value ranges from 0 - 100
        return int(QgsSymbolLayerV2Utils.decodeColor(values[0]).valueF() * 100)
    except:
        return None

def lightness(values, feature, parent):
    """
        Returns the lightness of a color, an integer between 0-100
        
        <p><h4>Syntax</h4>
        lightness(<i>color</i>)</p>

        <p><h4>Arguments</h4>
        <i>  color</i> &rarr; a color<br></p>
        
        <p><h4>Example</h4>
        <!-- Show example of function.-->
             lightness('125,255,125') &rarr; 74</p>
    """
    try:
        # Lightness ranges from 0 - 100
        return int(QgsSymbolLayerV2Utils.decodeColor(values[0]).lightnessF() * 100)
    except:
        return None

def saturation(values, feature, parent):
    """
        Returns the saturation of a color, an integer between 0-100
        
        <p><h4>Syntax</h4>
        saturation(<i>color</i>)</p>

        <p><h4>Arguments</h4>
        <i>  color</i> &rarr; a color<br></p>
        
        <p><h4>Example</h4>
        <!-- Show example of function.-->
             saturation('125,255,125') &rarr; 50</p>
    """
    try:
        # Saturation ranges from 0 - 100
        return int(QgsSymbolLayerV2Utils.decodeColor(values[0]).saturationF() * 100)
    except:
        return None