line.py

#

from bbox import BBox
from geometry import Geometry

#

polyline

class PolyLine(Geometry):

#

    def __init__(self, contours):
        self.contours = contours

#

returns the bounding box of the line

    def bbox(self):

#

        bbox = BBox()
        for pts in self.contours:
            for pt in pts:
                bbox.update(pt)
        return bbox

#

projects the line to a map projection

    def project(self, proj):

#

        contours = []
        for points in self.contours:
            pts = []
            for pt in points:
                if proj._visible(pt[0], pt[1]):
                    p = proj.project(pt[0], pt[1])
                    if p is not None:
                        pts.append(p)
                else:
                    if len(pts) > 0:
                        contours.append(pts)
                        pts = []
            if len(pts) > 0:
                contours.append(pts)
        return PolyLine(contours)

#

transforms the line to a new view

    def project_view(self, view):

#

        contours = []
        for points in self.contours:
            pts = []
            for pt in points:
                p = view.project(pt)
                pts.append(p)
            contours.append(pts)
        return PolyLine(contours)

#

constructs a svg representation of this line

    def to_svg(self, svg, round):

#

        path_str = ""
        if round is False:
            fmt = '%f,%f'
        else:
            fmt = '%.' + str(round) + 'f'
            fmt = fmt + ',' + fmt

        for points in self.contours:
            path_str += "M "
            pts = []
            for pt in points:
                pts.append(fmt % (pt[0], pt[1]))
            path_str += 'L '.join(pts)

        path = svg.node('path', d=path_str)
        return path

#

    def crop_to(self, geom):

#

skip

        return self

#

    def is_empty(self):
        return len(self.contours) == 0

#

    def unify(self, point_store, precision):
        from kartograph.simplify import unify_polygon
        for i in range(len(self.contours)):
            self.contours[i] = unify_polygon(self.contours[i], point_store, precision)

#

    def points(self):
        return self.contours

#

is called after the points of this geometry have been changed from outside this class

    def update(self):

#

        pass

#

simple line (= list of points)

class Line(Geometry):

#

    def __init__(self, points):
        self.pts = points

#