Python QtGui.QPainter类代码示例

    def testRenderRegion(self):
        l = QgsLayout(QgsProject.instance())
        l.initializeDefaults()

        # add a guide, to ensure it is not included in export
        g1 = QgsLayoutGuide(Qt.Horizontal, QgsLayoutMeasurement(15, QgsUnitTypes.LayoutMillimeters), l.pageCollection().page(0))
        l.guides().addGuide(g1)

        # add some items
        item1 = QgsLayoutItemShape(l)
        item1.attemptSetSceneRect(QRectF(10, 20, 100, 150))
        fill = QgsSimpleFillSymbolLayer()
        fill_symbol = QgsFillSymbol()
        fill_symbol.changeSymbolLayer(0, fill)
        fill.setColor(Qt.green)
        fill.setStrokeStyle(Qt.NoPen)
        item1.setSymbol(fill_symbol)
        l.addItem(item1)

        # get width/height, create image and render the composition to it
        size = QSize(560, 509)
        output_image = QImage(size, QImage.Format_RGB32)

        output_image.setDotsPerMeterX(self.dots_per_meter)
        output_image.setDotsPerMeterY(self.dots_per_meter)
        QgsMultiRenderChecker.drawBackground(output_image)
        painter = QPainter(output_image)
        exporter = QgsLayoutExporter(l)

        exporter.renderRegion(painter, QRectF(5, 10, 110, 100))
        painter.end()

        rendered_file_path = os.path.join(self.basetestpath, 'test_renderregion.png')
        output_image.save(rendered_file_path, "PNG")
        self.assertTrue(self.checkImage('renderregion', 'renderregion', rendered_file_path))

    def testRenderPage(self):
        l = QgsLayout(QgsProject.instance())
        l.initializeDefaults()

        # add some items
        item1 = QgsLayoutItemShape(l)
        item1.attemptSetSceneRect(QRectF(10, 20, 100, 150))
        fill = QgsSimpleFillSymbolLayer()
        fill_symbol = QgsFillSymbol()
        fill_symbol.changeSymbolLayer(0, fill)
        fill.setColor(Qt.green)
        fill.setStrokeStyle(Qt.NoPen)
        item1.setSymbol(fill_symbol)
        l.addItem(item1)

        # get width/height, create image and render the composition to it
        size = QSize(1122, 794)
        output_image = QImage(size, QImage.Format_RGB32)

        output_image.setDotsPerMeterX(self.dots_per_meter)
        output_image.setDotsPerMeterY(self.dots_per_meter)
        QgsMultiRenderChecker.drawBackground(output_image)
        painter = QPainter(output_image)
        exporter = QgsLayoutExporter(l)

        # valid page
        exporter.renderPage(painter, 0)
        painter.end()

        rendered_file_path = os.path.join(self.basetestpath, 'test_renderpage.png')
        output_image.save(rendered_file_path, "PNG")
        self.assertTrue(self.checkImage('renderpage', 'renderpage', rendered_file_path))

    def testRenderMarkerLayerDisabled(self):
        """ test that rendering a marker symbol with disabled layer works"""
        layer = QgsSimpleMarkerSymbolLayer()
        layer.setEnabled(False)

        symbol = QgsMarkerSymbol()
        symbol.changeSymbolLayer(0, layer)

        image = QImage(200, 200, QImage.Format_RGB32)
        painter = QPainter()
        ms = QgsMapSettings()

        geom = QgsGeometry.fromWkt('Point (1 2)')
        f = QgsFeature()
        f.setGeometry(geom)

        extent = QgsRectangle(0, 0, 4, 4)

        ms.setExtent(extent)
        ms.setOutputSize(image.size())
        context = QgsRenderContext.fromMapSettings(ms)
        context.setPainter(painter)
        context.setScaleFactor(96 / 25.4)  # 96 DPI

        painter.begin(image)
        image.fill(QColor(255, 255, 255))

        symbol.startRender(context)
        symbol.renderFeature(f, context)
        symbol.stopRender(context)
        painter.end()

        self.assertTrue(self.imageCheck('symbol_layer', 'symbollayer_disabled', image))

    def renderGeometry(self, symbol, geom, buffer=20):
        f = QgsFeature()
        f.setGeometry(geom)

        image = QImage(200, 200, QImage.Format_RGB32)

        painter = QPainter()
        ms = QgsMapSettings()
        extent = geom.get().boundingBox()
        # buffer extent by 10%
        if extent.width() > 0:
            extent = extent.buffered((extent.height() + extent.width()) / buffer)
        else:
            extent = extent.buffered(buffer / 2)

        ms.setExtent(extent)
        ms.setOutputSize(image.size())
        context = QgsRenderContext.fromMapSettings(ms)
        context.setPainter(painter)
        context.setScaleFactor(96 / 25.4)  # 96 DPI
        context.expressionContext().setFeature(f)

        painter.begin(image)
        try:
            image.fill(QColor(0, 0, 0))
            symbol.startRender(context)
            symbol.renderFeature(f, context)
            symbol.stopRender(context)
        finally:
            painter.end()

        return image

    def testSimpleLineWithOffset(self):
        """ test that rendering a polygon with simple line symbol with offset results in closed line"""
        layer = QgsSimpleLineSymbolLayer()
        layer.setOffset(-1)

        symbol = QgsFillSymbol()
        symbol.changeSymbolLayer(0, layer)

        image = QImage(200, 200, QImage.Format_RGB32)
        painter = QPainter()
        ms = QgsMapSettings()

        geom = QgsGeometry.fromWkt('Polygon((0 0, 10 0, 10 10, 0 10, 0 0))')
        f = QgsFeature()
        f.setGeometry(geom)

        extent = geom.geometry().boundingBox()
        # buffer extent by 10%
        extent = extent.buffer((extent.height() + extent.width()) / 20.0)

        ms.setExtent(extent)
        ms.setOutputSize(image.size())
        context = QgsRenderContext.fromMapSettings(ms)
        context.setPainter(painter)
        context.setScaleFactor(96 / 25.4)  # 96 DPI

        painter.begin(image)
        image.fill(QColor(255, 255, 255))

        symbol.startRender(context)
        symbol.renderFeature(f, context)
        symbol.stopRender(context)
        painter.end()

        self.assertTrue(self.imageCheck('symbol_layer', 'fill_simpleline_offset', image))

    def exportAsPdf(self):
        self.repaintModel(controls=False)
        filename, fileFilter = QFileDialog.getSaveFileName(self,
                                                           self.tr('Save Model As PDF'), '',
                                                           self.tr('PDF files (*.pdf *.PDF)'))
        if not filename:
            return

        if not filename.lower().endswith('.pdf'):
            filename += '.pdf'

        totalRect = self.scene.itemsBoundingRect()
        totalRect.adjust(-10, -10, 10, 10)
        printerRect = QRectF(0, 0, totalRect.width(), totalRect.height())

        printer = QPrinter()
        printer.setOutputFormat(QPrinter.PdfFormat)
        printer.setOutputFileName(filename)
        printer.setPaperSize(QSizeF(printerRect.width(), printerRect.height()), QPrinter.DevicePixel)
        printer.setFullPage(True)

        painter = QPainter(printer)
        self.scene.render(painter, printerRect, totalRect)
        painter.end()

        self.bar.pushMessage("", "Model was correctly exported as PDF", level=Qgis.Success, duration=5)
        self.repaintModel(controls=True)

    def testRenderLineLayerDisabled(self):
        """ test that rendering a line symbol with disabled layer works"""
        layer = QgsSimpleLineSymbolLayer()
        layer.setEnabled(False)

        symbol = QgsLineSymbol()
        symbol.changeSymbolLayer(0, layer)

        image = QImage(200, 200, QImage.Format_RGB32)
        painter = QPainter()
        ms = QgsMapSettings()

        geom = QgsGeometry.fromWkt('LineString (0 0,3 4,4 3)')
        f = QgsFeature()
        f.setGeometry(geom)

        extent = geom.constGet().boundingBox()
        # buffer extent by 10%
        extent = extent.buffered((extent.height() + extent.width()) / 20.0)

        ms.setExtent(extent)
        ms.setOutputSize(image.size())
        context = QgsRenderContext.fromMapSettings(ms)
        context.setPainter(painter)
        context.setScaleFactor(96 / 25.4)  # 96 DPI

        painter.begin(image)
        image.fill(QColor(255, 255, 255))

        symbol.startRender(context)
        symbol.renderFeature(f, context)
        symbol.stopRender(context)
        painter.end()

        self.assertTrue(self.imageCheck('symbol_layer', 'symbollayer_disabled', image))

    def exportAsSvg(self):
        self.repaintModel(controls=False)
        filename, fileFilter = QFileDialog.getSaveFileName(self,
                                                           self.tr('Save Model As SVG'), '',
                                                           self.tr('SVG files (*.svg *.SVG)'))
        if not filename:
            return

        if not filename.lower().endswith('.svg'):
            filename += '.svg'

        totalRect = self.scene.itemsBoundingRect()
        totalRect.adjust(-10, -10, 10, 10)
        svgRect = QRectF(0, 0, totalRect.width(), totalRect.height())

        svg = QSvgGenerator()
        svg.setFileName(filename)
        svg.setSize(QSize(totalRect.width(), totalRect.height()))
        svg.setViewBox(svgRect)
        svg.setTitle(self.model.displayName())

        painter = QPainter(svg)
        self.scene.render(painter, svgRect, totalRect)
        painter.end()

        self.bar.pushMessage("", self.tr("Successfully exported model as SVG to <a href=\"{}\">{}</a>").format(QUrl.fromLocalFile(filename).toString(), QDir.toNativeSeparators(filename)), level=Qgis.Success, duration=5)
        self.repaintModel(controls=True)

    def exportAsPdf(self):
        self.repaintModel(controls=False)
        filename, fileFilter = QFileDialog.getSaveFileName(self,
                                                           self.tr('Save Model As PDF'), '',
                                                           self.tr('PDF files (*.pdf *.PDF)'))
        if not filename:
            return

        if not filename.lower().endswith('.pdf'):
            filename += '.pdf'

        totalRect = self.scene.itemsBoundingRect()
        totalRect.adjust(-10, -10, 10, 10)
        printerRect = QRectF(0, 0, totalRect.width(), totalRect.height())

        printer = QPrinter()
        printer.setOutputFormat(QPrinter.PdfFormat)
        printer.setOutputFileName(filename)
        printer.setPaperSize(QSizeF(printerRect.width(), printerRect.height()), QPrinter.DevicePixel)
        printer.setFullPage(True)

        painter = QPainter(printer)
        self.scene.render(painter, printerRect, totalRect)
        painter.end()

        self.bar.pushMessage("", self.tr("Successfully exported model as PDF to <a href=\"{}\">{}</a>").format(QUrl.fromLocalFile(filename).toString(), QDir.toNativeSeparators(filename)), level=Qgis.Success, duration=5)
        self.repaintModel(controls=True)

    def testFromQPainter(self):
        """ test QgsRenderContext.fromQPainter """

        # no painter
        c = QgsRenderContext.fromQPainter(None)
        self.assertFalse(c.painter())
        # assuming 88 dpi as fallback
        self.assertAlmostEqual(c.scaleFactor(), 88 / 25.4, 3)

        # no painter destination
        p = QPainter()
        c = QgsRenderContext.fromQPainter(p)
        self.assertEqual(c.painter(), p)
        self.assertEqual(c.testFlag(QgsRenderContext.Antialiasing), False)
        self.assertAlmostEqual(c.scaleFactor(), 88 / 25.4, 3)

        im = QImage(1000, 600, QImage.Format_RGB32)
        dots_per_m = 300 / 25.4 * 1000  # 300 dpi to dots per m
        im.setDotsPerMeterX(dots_per_m)
        im.setDotsPerMeterY(dots_per_m)
        p = QPainter(im)
        p.setRenderHint(QPainter.Antialiasing)
        c = QgsRenderContext.fromQPainter(p)
        self.assertEqual(c.painter(), p)
        self.assertEqual(c.testFlag(QgsRenderContext.Antialiasing), True)
        self.assertAlmostEqual(c.scaleFactor(), dots_per_m / 1000, 3)  # scaleFactor should be pixels/mm

    def runTestForLayer(self, layer, testname):
        tempdir = tempfile.mkdtemp()

        layer = QgsVectorLayer(layer, 'Layer', 'ogr')
        QgsProject.instance().addMapLayer(layer)
        self.iface.mapCanvas().setExtent(layer.extent())

        geom = next(layer.getFeatures()).geometry()

        highlight = QgsHighlight(self.iface.mapCanvas(), geom, layer)
        color = QColor(Qt.red)
        highlight.setColor(color)
        highlight.setWidth(2)
        color.setAlpha(50)
        highlight.setFillColor(color)
        highlight.show()

        image = QImage(QSize(400, 400), QImage.Format_ARGB32)
        image.fill(Qt.white)
        painter = QPainter()
        painter.begin(image)
        self.iface.mapCanvas().render(painter)
        painter.end()
        control_image = os.path.join(tempdir, 'highlight_{}.png'.format(testname))
        image.save(control_image)
        checker = QgsRenderChecker()
        checker.setControlPathPrefix("highlight")
        checker.setControlName("expected_highlight_{}".format(testname))
        checker.setRenderedImage(control_image)
        self.assertTrue(checker.compareImages("highlight_{}".format(testname)))
        shutil.rmtree(tempdir)

    def renderMap(self):
        rendererContext = self.context
        if rendererContext.painter().device().logicalDpiX() != int(self.outputDpi):
            printScale = 25.4 / self.outputDpi  # OL DPI to printer pixels
            rendererContext.painter().scale(printScale, printScale)

        # render OpenLayers to image
        painter = QPainter(self.img)
        self.page.mainFrame().render(painter)
        painter.end()

        if self.img.size() != self.targetSize:
            targetWidth = self.targetSize.width()
            targetHeight = self.targetSize.height()
            # scale using QImage for better quality
            debug("    scale image: %i x %i -> %i x %i" % (
                self.img.width(), self.img.height(),
                  targetWidth, targetHeight), 3)
            self.img = self.img.scaled(targetWidth, targetHeight,
                                       Qt.KeepAspectRatio,
                                       Qt.SmoothTransformation)

        # save current state
        self.page.lastExtent = rendererContext.extent()
        self.page.lastViewPortSize = rendererContext.painter().viewport().size()
        self.page.lastLogicalDpi = rendererContext.painter().device().logicalDpiX()
        self.page.lastOutputDpi = self.outputDpi
        self.page.lastMapUnitsPerPixel = rendererContext.mapToPixel().mapUnitsPerPixel()

    def testLayout(self, page=0, pixelDiff=0):
        if self.layout is None:
            myMessage = "Layout not valid"
            return False, myMessage

        # load expected image
        self.setControlName("expected_" + self.test_name)

        # get width/height, create image and render the composition to it
        outputImage = QImage(self.size, QImage.Format_RGB32)

        outputImage.setDotsPerMeterX(self.dots_per_meter)
        outputImage.setDotsPerMeterY(self.dots_per_meter)
        QgsMultiRenderChecker.drawBackground(outputImage)
        p = QPainter(outputImage)
        self.layout.exporter().renderPage(p, page)
        p.end()

        renderedFilePath = QDir.tempPath() + QDir.separator() + QFileInfo(self.test_name).baseName() + "_rendered.png"
        outputImage.save(renderedFilePath, "PNG")

        self.setRenderedImage(renderedFilePath)

        testResult = self.runTest(self.test_name, pixelDiff)

        return testResult, self.report()

    def _svg_to_png(svg_file_path, rendered_file_path, width):
        svgr = QSvgRenderer(svg_file_path)

        height = width / svgr.viewBoxF().width() * svgr.viewBoxF().height()

        image = QImage(width, height, QImage.Format_ARGB32)
        image.fill(Qt.transparent)

        p = QPainter(image)
        p.setRenderHint(QPainter.Antialiasing, False)
        svgr.render(p)
        p.end()

        res = image.save(rendered_file_path, 'png')
        if not res:
            os.unlink(rendered_file_path)

    def image(self):
        width = (self.xmax - self.xmin + 1) * self.TILE_SIZE
        height = (self.ymax - self.ymin + 1) * self.TILE_SIZE
        image = QImage(width, height, QImage.Format_ARGB32_Premultiplied)
        p = QPainter(image)
        for tile in list(self.tiles.values()):
            if not tile.data:
                continue

            x = tile.x - self.xmin
            y = tile.y - self.ymin
            rect = QRect(x * self.TILE_SIZE, y * self.TILE_SIZE, self.TILE_SIZE, self.TILE_SIZE)

            timg = QImage()
            timg.loadFromData(tile.data)
            p.drawImage(rect, timg)
        return image