#
# AUTHOR(S): Anna Petrasova <kratochanna AT gmail>
#
# PURPOSE: This module contains functionality for managing region
# during rendering.
#
# COPYRIGHT: (C) 2021 Anna Petrasova, and by the GRASS Development Team
#
# This program is free software under the GNU General Public
# License (>=v2). Read the file COPYING that comes with GRASS
# for details.
"""Manage computational or display region settings for display (render) classes."""
import grass.script as gs
from grass.exceptions import CalledModuleError
from .utils import (
get_map_name_from_d_command,
estimate_resolution,
set_target_region,
get_rendering_size,
)
[docs]class RegionManagerForInteractiveMap:
"""Region manager for an interactive map (gets region from raster and vector)"""
def __init__(self, use_region, saved_region, src_env, tgt_env):
"""Manages region during rendering for interactive map.
:param use_region: if True, use either current or provided saved region,
else derive region from rendered layers
:param saved_region: if name of saved_region is provided,
this region is then used for rendering
:param src_env: source environment (original projection)
:param tgt_env: target environment (pseudomercator)
"""
self._use_region = use_region
self._saved_region = saved_region
self._src_env = src_env
self._tgt_env = tgt_env
self._resolution = None
# [SW, NE]: inverted to easily expand based on data, see _set_bbox
self._bbox = [[90, 180], [-90, -180]]
if self._use_region:
# tgt region already set, set resolution
self._resolution = self._get_psmerc_region_resolution()
self._set_bbox(self._src_env)
if self._saved_region:
self._src_env["GRASS_REGION"] = gs.region_env(
region=self._saved_region, env=self._src_env
)
set_target_region(src_env=self._src_env, tgt_env=self._tgt_env)
self._resolution = self._get_psmerc_region_resolution()
self._set_bbox(self._src_env)
@property
def bbox(self):
"""Bbox property for accessing maximum bounding box of all rendered layers."""
return self._bbox
@property
def resolution(self):
"""Resolution to be used for reprojection."""
return self._resolution
def _get_psmerc_region_resolution(self):
"""Get region resolution (average ns and ew) of psmerc mapset"""
reg = gs.region(env=self._tgt_env)
return (reg["nsres"] + reg["ewres"]) / 2
[docs] def set_region_from_raster(self, raster):
"""Sets computational region for rendering.
This functions sets computational region based on
a raster map in the target environment.
If user specified the name of saved region during object's initialization,
the provided region is used. If it's not specified
and use_region=True, current region is used.
Also enlarges bounding box based on the raster.
"""
if self._use_region or self._saved_region:
# target region and bbox already set
return
# set target location region extent
self._src_env["GRASS_REGION"] = gs.region_env(raster=raster, env=self._src_env)
set_target_region(src_env=self._src_env, tgt_env=self._tgt_env)
# set resolution based on r.proj estimate
env_info = gs.gisenv(env=self._src_env)
name, mapset = raster.split("@")
self._resolution = estimate_resolution(
raster=name,
mapset=mapset,
location=env_info["LOCATION_NAME"],
dbase=env_info["GISDBASE"],
env=self._tgt_env,
)
self._set_bbox(self._src_env)
[docs] def set_bbox_vector(self, vector):
"""Enlarge bounding box based on vector"""
if self._saved_region or self._use_region:
return
env = self._src_env.copy()
env["GRASS_REGION"] = gs.region_env(vector=vector, env=env)
self._set_bbox(env)
def _set_bbox(self, env):
bbox = gs.parse_command("g.region", flags="bg", env=env)
south = float(bbox["ll_s"])
west = float(bbox["ll_w"])
north = float(bbox["ll_n"])
east = float(bbox["ll_e"])
if self._bbox[0][0] > south:
self._bbox[0][0] = south
if self._bbox[0][1] > west:
self._bbox[0][1] = west
if self._bbox[1][0] < north:
self._bbox[1][0] = north
if self._bbox[1][1] < east:
self._bbox[1][1] = east
[docs]class RegionManagerFor2D:
"""Region manager for 2D displays (gets region from display commands)"""
def __init__(self, use_region, saved_region, width, height, env):
"""Manages region during rendering.
:param use_region: if True, use either current or provided saved region,
else derive region from rendered layers
:param saved_region: if name of saved_region is provided,
this region is then used for rendering
:param width: rendering width
:param height: rendering height
:param env: environment for rendering
"""
self._env = env
self._width = width
self._height = height
self._use_region = use_region
self._saved_region = saved_region
self._extent_set = False
self._resolution_set = False
self._size_set = False
[docs] def set_region_from_env(self, env):
"""Copies GRASS_REGION from provided environment
to local environment to set the computational region"""
if "GRASS_REGION" in env:
self._env["GRASS_REGION"] = env["GRASS_REGION"]
[docs] def adjust_rendering_size_from_region(self):
"""Sets the environmental render width and height variables
based on the region dimensions. Only first call of this
method sets the variables, subsequent calls do not adjust them.
"""
if not self._size_set:
region = gs.region(env=self._env)
width, height = get_rendering_size(region, self._width, self._height)
self._env["GRASS_RENDER_WIDTH"] = str(round(width))
self._env["GRASS_RENDER_HEIGHT"] = str(round(height))
# only when extent is set you can disable future size setting
if self._extent_set:
self._size_set = True
[docs] def set_region_from_command(self, module, **kwargs):
"""Sets computational region for rendering.
This functions identifies a raster/vector map from command
and tries to set computational region based on that.
It takes the extent from the first layer (raster or vector)
and resolution and alignment from first raster layer.
If user specified the name of saved region during object's initialization,
the provided region is used. If it's not specified
and use_region=True, current region is used.
"""
if self._saved_region:
self._env["GRASS_REGION"] = gs.region_env(
region=self._saved_region, env=self._env
)
return
if self._use_region:
# use current
return
if self._resolution_set and self._extent_set:
return
name = get_map_name_from_d_command(module, **kwargs)
if not name:
return
if len(name.split()) > 1:
name = name.split()[0]
try:
if module.startswith("d.vect"):
if not self._resolution_set and not self._extent_set:
self._env["GRASS_REGION"] = gs.region_env(
vector=name, env=self._env
)
self._extent_set = True
else:
if not self._resolution_set and not self._extent_set:
self._env["GRASS_REGION"] = gs.region_env(
raster=name, env=self._env
)
self._extent_set = True
self._resolution_set = True
elif not self._resolution_set:
self._env["GRASS_REGION"] = gs.region_env(align=name, env=self._env)
self._resolution_set = True
except CalledModuleError:
return
[docs]class RegionManagerFor3D:
"""Region manager for 3D displays (gets region from m.nviz.image command)"""
def __init__(self, use_region, saved_region):
"""Manages region during rendering.
:param use_region: if True, use either current or provided saved region,
else derive region from rendered layers
:param saved_region: if name of saved_region is provided,
this region is then used for rendering
"""
self._use_region = use_region
self._saved_region = saved_region
[docs] def set_region_from_command(self, env, **kwargs):
"""Sets computational region for rendering.
This functions identifies a raster map from m.nviz.image command
and tries to set computational region based on that.
If user specified the name of saved region during object's initialization,
the provided region is used. If it's not specified
and use_region=True, current region is used.
"""
if self._saved_region:
env["GRASS_REGION"] = gs.region_env(region=self._saved_region, env=env)
return
if self._use_region:
# use current
return
if "elevation_map" in kwargs:
elev = kwargs["elevation_map"].split(",")[0]
try:
env["GRASS_REGION"] = gs.region_env(raster=elev, env=env)
except CalledModuleError:
return
[docs]class RegionManagerForTimeSeries:
"""Region manager for TimeSeries visualizations."""
def __init__(self, use_region, saved_region, env):
"""Manages region during rendering.
:param use_region: if True, use either current or provided saved region,
else derive region from rendered layers
:param saved_region: if name of saved_region is provided,
this region is then used for rendering
:param env: environment for rendering
"""
self._env = env
self._use_region = use_region
self._saved_region = saved_region
[docs] def set_region_from_timeseries(self, timeseries):
"""Sets computational region for rendering.
This function sets the computation region from the extent of
a space-time dataset by using its bounding box and resolution.
If user specified the name of saved region during object's initialization,
the provided region is used. If it's not specified
and use_region=True, current region is used.
"""
if self._saved_region:
self._env["GRASS_REGION"] = gs.region_env(
region=self._saved_region, env=self._env
)
return
if self._use_region:
# use current
return
# Get extent, resolution from space time dataset
info = gs.parse_command("t.info", input=timeseries, flags="g", env=self._env)
# Set grass region from extent
self._env["GRASS_REGION"] = gs.region_env(
n=info["north"],
s=info["south"],
e=info["east"],
w=info["west"],
nsres=info["nsres_min"],
ewres=info["ewres_min"],
)
