roadgen.py 文件源码

def dashed_line(self, coordinates, dash_length, dash_width ):
        #estimate the curve length to generate a segment count which will approximate the desired dash lenght
        est_curve_len = (self.vector_len(coordinates[:,2] - coordinates[:,0] ) + 
                        self.vector_len(coordinates[:,1] - coordinates[:,0] ) + 
                        self.vector_len(coordinates[:,2] - coordinates[:,1] ) )/2
        segments = int(est_curve_len/dash_length)
        x, y = bezier_curve(coordinates[0, :] - self.cropsize[0], 
                coordinates[1, :] - self.cropsize[1], segments)
        dash_line = np.array([x, y])

        #initializing empty indices
        rrr = np.empty(0, dtype=int)
        ccc = np.empty(0, dtype=int)
        for dash in range( int(segments/2) ):
            offset = .5*dash_width * self.perpendicular(dash_line[:,dash*2]-dash_line[:,dash*2+1])
            d_path = np.array( [ dash_line[:,dash*2] + offset, dash_line[:,dash*2 +1] + offset, 
                        dash_line[:,dash*2+1] - offset, dash_line[:,dash*2 ] - offset,
                        dash_line[:,dash*2] + offset] )
            rr, cc = polygon(d_path.astype(int)[:,1], d_path.astype(int)[:,0], 
                            (self.view_res[1], self.view_res[0]) )
            rrr = np.append(rrr, rr)
            ccc = np.append(ccc, cc)

        return rrr, ccc

    #Makes randomly shaped polygon noise to screw with the learning algorithm