xmsstamper

Introduction

xmsstamper is a library used to generate "feature stamps". Feature stamps refer to the insertion of man-made structures into a natural topography or bathymetry set. In common terms, this means adding an embankment (such as a levy) or dredging a channel. A stamped feature usually a linear object or centerline. More information on feature stamping can be found here https://xmswiki.com/wiki/SMS:Feature_Stamping.

The basic workflow is to first define the land surface or bathymetry as a TIN (triangular surface). Then define a feature stamp consisting of a center line, cross sections along the center line, and end caps. The feature stamp is used to generate a new TIN that is cut off by the land surface or bathemetry.

This example will show how to use the classes in the library with very simple examples.

import numpy as np
import holoviews as hv

from shapely.geometry import Polygon
from holoviews.streams import Params

import hvplot.pandas
import hvplot.xarray

import xmsmesh
import xmsstamper
import xmsinterp
import xmsgrid

import ugrid_tools

hv.extension('bokeh')

# define a tin, used later
surface_pts = [(-5,-15,9.5), (-5,45,9.5), (70, 45,9.5), (70,-15,9.5)]
tin = xmsinterp.triangulate.Tin(pts=surface_pts)
tin.triangulate()

x = [x[0] for x in tin.pts]
y = [y[1] for y in tin.pts]
z = [z[2] for z in tin.pts]
nodes = np.column_stack([x, y, z])
nodes = hv.Points(nodes, vdims=['z'])

Define Center Line Points and type of Stamp

stamp_type = "fill"
centerline = [
    (0.0, 0.0, 10.0),
    (10.0, 0.0, 10.0),
]

Define a Cross Section

# symetric cross section, left and right are equal
left = right = [(0, 10.0), (2.0, 10.0), (3.0, 9.5)]
index_left_shoulder = index_right_shoulder = 1
left_max = right_max = 5.0
cs = xmsstamper.stamper.StampCrossSection(
    left=left,
    right=right,
    index_left_shoulder=index_left_shoulder,
    index_right_shoulder=index_right_shoulder,
    left_max=left_max,
    right_max=right_max,
)
cs_list = [cs] * len(centerline)

Create a StamperIO class to perform the Stamp operation

stamp_io = xmsstamper.stamper.StamperIo(
    stamping_type=stamp_type,
    centerline=centerline,
    cs=cs_list,
)

Generate a Stamp

xmsstamper.stamper.stamper.stamp(stamp_io)
out_tin = stamp_io.get_out_tin()

Draw the output TIN

# draw the output TIN
tris = [x for x in zip(*[iter(out_tin.tris)] * 3)]

x, y, z = zip(*out_tin.pts)
stamp_nodes = np.column_stack([x, y, z])
stamp_nodes = hv.Points(stamp_nodes, vdims='z')

trimesh = hv.TriMesh((tris, stamp_nodes))
nodes * stamp_nodes * trimesh.opts(
   hv.opts.TriMesh(filled=True, colorbar=True, cmap='viridis', edge_color='z', edge_alpha=0.4, node_size=3)
)

Extend Centerline and add another cross section

centerline.append((50, 0, 10))

left = right = [(0, 10.0), (4.0, 10.0), (3.0, 9.0)]
index_left_shoulder = index_right_shoulder = 1
left_max = right_max = 10.0
cs = xmsstamper.stamper.StampCrossSection(
    left=left,
    right=right,
    index_left_shoulder=index_left_shoulder,
    index_right_shoulder=index_right_shoulder,
    left_max=left_max,
    right_max=right_max,
)
cs_list.append(cs)

stamp_io = xmsstamper.stamper.StamperIo(
    stamping_type=stamp_type,
    centerline=centerline,
    cs=cs_list,
)

Create new Stamp and Draw out put

xmsstamper.stamper.stamper.stamp(stamp_io)
out_tin = stamp_io.get_out_tin()

# draw the output TIN
tris = [x for x in zip(*[iter(out_tin.tris)] * 3)]

x, y, z = zip(*out_tin.pts)
stamp_nodes = np.column_stack([x, y, z])
stamp_nodes = hv.Points(stamp_nodes, vdims='z')

trimesh = hv.TriMesh((tris, stamp_nodes))
nodes * stamp_nodes * trimesh.opts(
   hv.opts.TriMesh(filled=True, colorbar=True, cmap='viridis', edge_color='z', edge_alpha=0.4, node_size=3)
)

Add End Caps to beginning of center line

wing_wall = xmsstamper.stamper.WingWall(wing_wall_angle = -30)

first_end_cap = xmsstamper.stamper.StamperEndCap(wing_wall=wing_wall)

stamp_io = xmsstamper.stamper.StamperIo(
    stamping_type=stamp_type,
    centerline=centerline,
    cs=cs_list,
    first_end_cap=first_end_cap,
)
xmsstamper.stamper.stamper.stamp(stamp_io)
out_tin = stamp_io.get_out_tin()

# draw the output TIN
tris = [x for x in zip(*[iter(out_tin.tris)] * 3)]

x, y, z = zip(*out_tin.pts)
stamp_nodes = np.column_stack([x, y, z])
stamp_nodes = hv.Points(stamp_nodes, vdims='z')

trimesh = hv.TriMesh((tris, stamp_nodes))
nodes * stamp_nodes * trimesh.opts(
   hv.opts.TriMesh(filled=True, colorbar=True, cmap='viridis', edge_color='z', edge_alpha=0.4, node_size=3)
)

Add End Caps to end of center line

guidebank = xmsstamper.stamper.Guidebank(n_pts=10, radius1=30, radius2=20, side=0, width=4)

last_end_cap = xmsstamper.stamper.StamperEndCap(guidebank=guidebank)
stamp_io = xmsstamper.stamper.StamperIo(
    stamping_type=stamp_type,
    centerline=centerline,
    cs=cs_list,
    first_end_cap=first_end_cap,
    last_end_cap=last_end_cap
)
xmsstamper.stamper.stamper.stamp(stamp_io)
out_tin = stamp_io.get_out_tin()

# draw the output TIN
tris = [x for x in zip(*[iter(out_tin.tris)] * 3)]

x, y, z = zip(*out_tin.pts)
stamp_nodes = np.column_stack([x, y, z])
stamp_nodes = hv.Points(stamp_nodes, vdims='z')

trimesh = hv.TriMesh((tris, stamp_nodes))
nodes * stamp_nodes * trimesh.opts(
   hv.opts.TriMesh(filled=True, colorbar=True, cmap='viridis', edge_color='z', edge_alpha=0.4, node_size=3)
)

Specify a land surface to cut off the stamp

stamp_io = xmsstamper.stamper.StamperIo(
    stamping_type=stamp_type,
    centerline=centerline,
    cs=cs_list,
    first_end_cap=first_end_cap,
    last_end_cap=last_end_cap,
    bathymetry=tin,
)
xmsstamper.stamper.stamper.stamp(stamp_io)
out_tin = stamp_io.get_out_tin()

# draw the output TIN
tris = [x for x in zip(*[iter(out_tin.tris)] * 3)]

x, y, z = zip(*out_tin.pts)
stamp_nodes = np.column_stack([x, y, z])
stamp_nodes = hv.Points(stamp_nodes, vdims='z')

trimesh = hv.TriMesh((tris, stamp_nodes))
nodes *stamp_nodes * trimesh.opts(
   hv.opts.TriMesh(filled=True, colorbar=True, cmap='viridis', edge_color='z', edge_alpha=0.4, node_size=3)
)