sanya-dbms/processing/tools/Raster/FishNet.py

# -*- coding: utf-8 -*-

__author__ = 'wanger'
__description__ = '处理渔网数据  判断网格是否为自由 增加标签'
__date__ = '2024-11-25'
__copyright__ = '(C) 2024 by siwei'
__revision__ = '1.0'

import os
from qgis.PyQt.QtCore import QCoreApplication
from qgis.core import (QgsProcessing,
                       QgsVectorLayer,
                       QgsFeatureSink,
                       QgsProcessingException,
                       QgsProcessingAlgorithm,
                       QgsProcessingParameterFile,
                       QgsProcessingParameterFeatureSource,
                       QgsProcessingParameterFeatureSink)
from qgis import processing


class FishNetProcessingAlgorithm(QgsProcessingAlgorithm):
    INPUT = 'INPUT'

    def tr(self, string):
        return QCoreApplication.translate('Processing', string)

    def createInstance(self):
        return FishNetProcessingAlgorithm()

    def name(self):
        return 'makeFishNet'

    def displayName(self):
        return self.tr('处理网格数据')

    def group(self):
        return self.tr('栅格数据')

    def groupId(self):
        return 'metadata'

    def shortHelpString(self):
        return self.tr("将输入的网格数据进行检查，将接边自由的要素做标记。")

    def initAlgorithm(self, config=None):
        self.addParameter(QgsProcessingParameterFile(
            self.INPUT,
            '网格数据',
            extension='shp'  # 设置文件过滤器，只允许选择shp文件
        ))

    # 定义检查一个网格单元格上下左右是否有相邻的网格单元
    def check_neighbors(self, feature, layer):
        # 获取当前单元格的几何
        geom = feature.geometry()
        bbox = geom.boundingBox()  # 获取网格单元的包围盒（bounding box）
        # 提取当前网格的中心点位置
        center_x, center_y = geom.centroid().asPoint()
        # 定义上下左右偏移量（单位为网格的大小，假设网格是正方形或矩形）
        tolerance = 1e-5  # 设定一个微小的容忍误差，用于比较几何形状
        neighbors = {
            'north': None,
            'south': None,
            'west': None,
            'east': None
        }
        for other_feature in layer.getFeatures():
            if other_feature.id() == feature.id():
                continue  # 跳过自己
            other_geom = other_feature.geometry()
            # 检查上、下、左、右的邻接
            if abs(center_y - other_geom.centroid().asPoint().y()) < tolerance and other_geom.centroid().asPoint().x() < center_x:
                neighbors['west'] = other_feature
            elif abs(
                    center_y - other_geom.centroid().asPoint().y()) < tolerance and other_geom.centroid().asPoint().x() > center_x:
                neighbors['east'] = other_feature
            elif abs(
                    center_x - other_geom.centroid().asPoint().x()) < tolerance and other_geom.centroid().asPoint().y() < center_y:
                neighbors['south'] = other_feature
            elif abs(
                    center_x - other_geom.centroid().asPoint().x()) < tolerance and other_geom.centroid().asPoint().y() > center_y:
                neighbors['north'] = other_feature
        return neighbors

    # 执行
    def processAlgorithm(self, parameters, context, feedback):
        shp_file_path = self.parameterAsString(parameters, self.INPUT, context)
        # 检查文件路径是否有效
        if not os.path.exists(shp_file_path):
            feedback.reportError(f"指定的文件路径 {shp_file_path} 不存在！")
            return {}

        # 加载Shapefile为QgsVectorLayer
        layer = QgsVectorLayer(shp_file_path, "Vector Layer", 'ogr')
        print(layer)
        layer.startEditing()
        # 获取所有要素（假设网格单元是矩形或正方形）
        features = list(layer.getFeatures())
        # 遍历所有网格单元，检查相邻的网格
        for feature in features:
            neighbors = self.check_neighbors(feature, layer)
            for direction, neighbor in neighbors.items():
                if neighbor:
                    print(f"")
                else:
                    # 更新字段值
                    feature.setAttribute(direction, "自由")
                    # 更新要素
                    layer.updateFeature(feature)
        # 保存编辑
        layer.commitChanges()
        return {
            "状态": "处理成功"
        }