import logging # 导入自定义日志工具 from qgis._core import QgsScaleBarSettings, QgsLayoutExporter, QgsCoordinateTransform, QgsCoordinateReferenceSystem, \ QgsPointXY, QgsGeometry, QgsRectangle class MapUtils: """出图工具类（封装地图缩放、文本更新、比例尺调整、导出等功能）""" def __init__(self, config, project, layout): self.config = config # 配置参数 self.project = project # QGIS项目对象 self.layout = layout # 布局对象（用于地图排版） self.imap = layout.itemById("Map") # 获取ID为"Map"的地图项 # 缩放 def Zoom(self, rule, data): logging.info(data) # 记录缩放参数日志 zoom = MapZoom(self.project, self.layout, self.imap) # 创建缩放操作对象 # 2024 Zoom转换（将数字规则映射为方法名） # NO("10", "不缩放"), # PAN("11", "平移"), # LAYER("12", "单图层"), # M_LAYER("13", "多图层"), # DISTANCE("14", "距离"), # M_LAYER2("15", "按图层合并缩放"); if rule == "11": rule = "FlatToCenter" # 平移至中心点 elif rule == "12": rule = "Layer" # 单图层缩放 elif rule == "13": rule = "LayerIntersect" # 多图层相交缩放 elif rule == "14": rule = "CenterDistance" # 中心距离缩放 elif rule == "15": rule = "LayerMerged" # 多图层合并缩放 else: rule = "FlatToCenter" # 默认平移至中心点 eval("zoom." + rule + "(data)") # 动态调用对应缩放方法 # 文本更新 def Update(self, model, key): label = self.layout.itemById(key) # 获取布局中ID为key的文本标签 if (label != None): label.setText(model[key]) # 更新标签文本为model中key对应的值 # 比例尺更新 def UpdateScale(self): ScaleBar = self.layout.itemById("ScaleBar") # 获取ID为"ScaleBar"的比例尺控件 if ScaleBar == None: logging.warning("比例尺不存在或控件标识不等于 ScaleBar") # 日志警告 return # 设置比例尺段大小模式为"适应宽度" ScaleBar.setSegmentSizeMode(QgsScaleBarSettings.SegmentSizeMode.SegmentSizeFitWidth) ScaleBar.setMaximumBarWidth(70) # 最大宽度 ScaleBar.setMinimumBarWidth(40) # 最小宽度 # 布局设置器 def QgsLayoutSettings(self): dpi = self.config["qgis"]["exportDpi"] # 设置dpi # 设置多个导出格式 settings = { 'PDF': QgsLayoutExporter.PdfExportSettings(), 'PNG': QgsLayoutExporter.ImageExportSettings(), 'JPG': QgsLayoutExporter.ImageExportSettings(), 'SVG': QgsLayoutExporter.SvgExportSettings() } for img_format in ['PNG', 'JPG']: settings[img_format].dpi = dpi settings['JPG'].jpegQuality = 85 return settings['PNG'] # 导出图片 def Export(self, path): try: qle = QgsLayoutExporter(self.layout) # 创建布局导出器 # 布局设置 setting = self.QgsLayoutSettings() # 导出为图片 res = qle.exportToImage(path, setting) except Exception as e: raise Exception(f"导出失败... {str(e)}") class MapZoom: """地图缩放操作类（封装多种缩放逻辑）""" def __init__(self, project, layout, imap): self.project = project # QGIS项目对象 self.layout = layout # 布局对象 self.imap = imap # 地图项对象 # 设置坐标系转换 def SetSrc(self, crs): qct = QgsCoordinateTransform() # 坐标系转换对象 qct.setDestinationCrs(self.imap.crs()) # 目标坐标系为地图当前坐标系 if crs == None: qct.setSourceCrs(QgsCoordinateReferenceSystem("EPSG:4326")) # 源坐标系默认WGS84（经纬度） else: qct.setSourceCrs(crs) # 自定义源坐标系 return qct # 平移至中心点 def FlatToCenter(self, data): logging.info("平移至中心点") qct = self.SetSrc(None) # 源坐标系为WGS84 point = QgsPointXY(float(data["X"]), float(data["Y"])) # 解析中心点坐标（经纬度） qgm = QgsGeometry.fromWkt(point.asWkt()) # 转换为QGIS几何对象 # 坐标转换（从源坐标系到地图坐标系） qgm.transform(qct, QgsCoordinateTransform.TransformDirection.ForwardTransform) cpoint = qgm.asPoint() # 转换后的中心点 # 保持当前地图宽度和高度，以新中心点创建矩形范围 qr = QgsRectangle.fromCenterAndSize(cpoint, self.imap.extent().width(), self.imap.extent().height()) self.imap.zoomToExtent(qr) # 缩放至该范围（实现平移） # 中心距离缩放（以中心点为圆心，指定距离为半径缩放） def CenterDistance(self, data): logging.info("中心距离") qct = self.SetSrc(None) point = QgsPointXY(float(data["X"]), float(data["Y"])) # 中心点坐标 qgm = QgsGeometry.fromWkt(point.asWkt()) qgm.transform(qct, QgsCoordinateTransform.TransformDirection.ForwardTransform) # 缓冲距离（单位：公里，转换为米后缓冲），并扩大10%范围 box = qgm.buffer(float(data["value"]) / 1000, 100).boundingBox() # 平面 4326 # box = qgm.buffer(float(data["value"])/111,100).boundingBox()#投影坐标系下的缓冲计算 self.imap.zoomToExtent(box.buffered(box.width() * 0.1)) # 按单图层缩放（缩放至指定图层范围） def Layer(self, data): logging.info("按图层缩放") layers = self.project.mapLayersByName(data["value"]) # 根据名称获取图层 if len(layers) == 0: logging.warning("图层不存在：" + data["value"]) # 图层不存在时警告 return layer = layers[0] if layer.featureCount() == 0.0: # 图层无要素时，默认平移至中心点 self.FlatToCenter(data) return qct = self.SetSrc(layer.crs()) # 源坐标系为图层坐标系 # 将图层范围转换为几何对象 qgm = QgsGeometry.fromWkt(layer.extent().asWktPolygon()) qgm.transform(qct, QgsCoordinateTransform.TransformDirection.ForwardTransform) # 转换到地图坐标系 box = qgm.boundingBox() # 获取范围矩形 self.imap.zoomToExtent(box.buffered(box.width() * 0.1)) # 扩大10%范围后缩放 # 多图层合并缩放（缩放至多个图层的合并范围） def LayerMerged(self, data): logging.info("多图层合并") layers = data["value"].split(",") # 图层名称以逗号分隔 box = None for lay in layers: temp = self.project.mapLayersByName(lay) if len(temp) == 0: logging.warning("图层不存在：" + lay) else: layer = temp[0] qct = self.SetSrc(layer.crs()) qgm = QgsGeometry.fromWkt(layer.extent().asWktPolygon()) qgm.transform(qct, QgsCoordinateTransform.TransformDirection.ForwardTransform) if box == None: box = qgm.boundingBox() # 初始化范围 else: box.combineExtentWith(qgm.boundingBox()) # 合并范围 if box != None: self.imap.zoomToExtent(box.buffered(box.width() * 0.1)) # 扩大10%范围后缩放 # 多图层相交缩放（缩放至多个图层的相交范围） def LayerIntersect(self, data): logging.info("多图层相交") layers = data["value"].split(",") # 图层名称以逗号分隔 box = None for lay in layers: temp = self.project.mapLayersByName(lay) if len(temp) == 0: logging.warning("图层不存在：" + lay) else: layer = temp[0] qct = self.SetSrc(layer.crs()) layer.selectAll() # 选中图层所有要素 geom = None # 合并选中要素的几何范围 for feature in layer.selectedFeatureIds(): if geom == '': geom = layer.getGeometry(feature) else: geom = geom.combine(layer.getGeometry(feature)) qgm = QgsGeometry.fromWkt(geom.asWkt()) qgm.transform(qct, QgsCoordinateTransform.TransformDirection.ForwardTransform) if box == None: box = qgm.boundingBox() # 初始化范围 else: box = box.intersection(qgm) # 计算相交范围 if box != None: box = box.boundingBox() self.imap.zoomToExtent(box.buffered(box.width() * 0.1)) # 扩大10%范围后缩放