Python 读取DXF文件

至于dxf文件的格式在之前的博文中已经有详细的叙述，在此将不做赘述。

 

from Point import Point
class DXFReaderImpl:
    def __init__(self,file):
        self.file = file
        self.points = [] ## 用于记录点实体的坐标值
        self.points_line = []  ## 用于记录线段的各端点坐标值，包括直线和折线两种线型
        self.points_polygon = [] ## 用于纪录多边形的顶点坐标值

    def readDXF(self):
        firstLine =""
        secondLine = ""
        secondLine = self.file.readline().strip()

        while secondLine != "EOF":
            if firstLine.strip() == "0" and secondLine.strip()== "LWPOLYLINE":
                self.readPolyline()

            if firstLine.strip() == "0" and secondLine.strip() == "LINE":
                self.readLines()

            if firstLine.strip() == "0" and secondLine.strip() == "POINT":
                pass
            firstLine = secondLine
            secondLine = self.file.readline().strip()

        print "there are " + str(i) + "polyline"

##
##    def readPolygon(self):
##        pass
## read polyline. In dxf file,polygon is a closed polyline
    def readPolyline(self):
        counter = 0
        numofvertex = 1
        flagofPolygon = 0
        x = 0
        y = 0
        firstLine = "LWPOLYLINE"
        secondLine = self.file.readline().strip()
        pointList = []
        while counter<=numofvertex:
            if firstLine == "90":
                numofvertex = int(secondLine)
            if firstLine == "70":
                flagofPolygon = int(secondLine)
            if firstLine == "10":
                x = float(secondLine)
            if firstLine == "20":
                y = float(secondLine)
                pointList.append(Point(x,y))
                counter = counter + 1
            firstLine = secondLine
            secondLine = self.file.readline().strip()

        if flagofPolygon == 0:
            self.points_line.append(pointList)
        else:
            self.points_polygon.append(pointList)

    def readPoint(self):
        firstLine = "POINT"
        secondLine = self.file.readline().strip()
        x = 0.0
        y = 0.0
        while firstLine != "30":
            if firstLine == "10":
                x = float(secondLine)
           if firstLine == "20":
                y = float(secondLine)
	   firstLine = secondLine
	   secondList = self.file.readline().strip();
        self.points.append(Point(x,y))
## read  straight line
    def readLines(self):
        x1 = 0.0
        y1 = 0.0
        x2 = 0.0
        y2 = 0.0
        firstLine = "POINT"
##        secondLine = ""
        seondLine = self.file.readline().strip()
        while firstLine != "31":
            if firstLine == "10":
                x1 = float(secondLine)
            if firstLine == "20":
                y1 = float(secondLine)
            if firstLine == "11":
                x2 = float(secondLine)
            if firstLine == "21":
                y2 = float(secondLine)
            firstLine = secondLine
            secondLine = self.file.readline().strip()

        tempLine = []
        tempLine.append(Point(x1,y1))
        tempLine.append(Point(x2,y2))
        self.points_line.append(tempLine)


if __name__=="__main__":
    file = open("D:\\test.dxf","r")

    reader = DXFReaderImpl(file)
    reader.readDXF()
    i = 1
    for temp in reader.points_polygon:
        print " this is the " + str(i) + " polygon"
        for points in temp:
            print str(points.x) + "   " + str(points.y)
        i = i + 1
##    i = 1
##    for temp in reader.points_line:
##        print " this is the " + str(i) + " polyline"
##        for points in temp:
##            print str(points.x) + "  " + str(points.y)
##        i += 1
    print "over"

 此段代码主要用于读取点，直线，折线，多边形等四种实体的坐标值。