Scene loader#
This page presents the canopy scene loader. A scene is composed by a
scenario.json file and a set of mesh files. The scenario.json file
contains the description of the scene, including the properties of the surface
and canopies within the scene. The mesh files contain the geometry of the canopy
elements.
The scenario.json file is structured to define specific properties of the
surface and canopies within a scene. It closely aligns with the expected scene
description format for the CanopyExperiment
within its surface and canopy fields.
Below is an example scenario.json containing a Lambertian surface and a
discrete canopy composed of mesh tree elements:
{
"surface": {
"type": "lambertian",
"reflectance": {
"quantity": "reflectance",
"wavelengths": [
442.95,
490.45,
560.4,
665.25,
681.55,
709.1,
754.15,
833.5,
865.6,
1242.5,
1610.5,
2120.0,
2199.0
],
"wavelengths_units": "nanometer",
"values": [
0.882742,
0.897852,
0.907004,
0.910396,
0.913883,
0.902941,
0.900788,
0.856648,
0.848049,
0.368409,
0.04536,
0.016815,
0.053261
],
"type": "interpolated"
}
},
"canopy": {
"type": "discrete_canopy",
"instanced_canopy_elements": [
{
"canopy_element": {
"type": "mesh_tree",
"id": "PIMO1",
"mesh_tree_elements": [
{
"id": "Wood",
"mesh_filename": "tree-species/Pinus-Montana/PIMO1/Pinus_mugo_PIMO1_-_Original/Wood.ply",
"reflectance": {
"quantity": "reflectance",
"wavelengths": {
"values": [
442.95,
490.45,
560.4,
665.25,
681.55,
709.1,
754.15,
833.5,
865.6,
1242.5,
1610.5,
2120.0,
2199.0
],
"units": "nanometer",
"type": "interpolated"
},
"values": [
0.072764,
0.082621,
0.109325,
0.157819,
0.167218,
0.200941,
0.239725,
0.303587,
0.329257,
0.525503,
0.511729,
0.383173,
0.394486
],
"type": "interpolated"
}
}
]
},
"instance_positions": [
[
[
0.2813481616359169,
0.9596057586030265,
0.0,
18.5271
],
[
-0.9596057586030265,
0.2813481616359169,
0.0,
97.4987
],
[
0.0,
0.0,
1.0,
0.0
],
[
0.0,
0.0,
0.0,
1.0
]
]
]
}
],
"size": [
103.1214,
103.2308,
15.0213
]
}
}
The folder structure for the above example would be:
.
├── scenario.json
└── tree-species
└── Pinus-Montana
└── PIMO1
└── Pinus_mugo_PIMO1_-_Original
└── Wood.ply
Differences from CanopyExperiment#
- Mesh filename
The
mesh_filenamefield within the canopy element specifies the relative path to the mesh file. This path is relative to thescenario.jsonfile itself. Upon loading the scene, this relative path will be expanded to the absolute path where the mesh file is located.- Instance positions 1The current implementation supports translations only. Support for rotations is foreseen in a future update.
Instance positions within the canopy configuration are described using a 4x4 affine transformation matrix. This matrix details the transformations applied to position the original mesh within the scene.1The current implementation supports translations only. Support for rotations is foreseen in a future update.
Custom spectral properties#
The reflectance field within the surface and canopy elements can be
customized using custom spectral properties. To do so, a dictionary describing
the spectral to be used is provided with matching canopy_element and
mesh_tree_elements ids. An example of a custom spectral property is shown
below:
spectral_data = {
"PIMO1": {
"Wood": {
"reflectance": (
{
"quantity": "reflectance",
"wavelengths": [
442.948,
490.448,
560.43045,
665.2445,
681.556,
709.1095,
754.184,
833.5,
865.587,
1242.5,
1610.5,
2120.0,
2199.0,
],
"wavelengths_units": "nanometer",
"values": [
0.053892,
0.057882,
0.136485,
0.055265,
0.052734,
0.214271,
0.4771,
0.494542,
0.496112,
0.461875,
0.332809,
0.158912,
0.181612,
],
"type": "interpolated",
}
),
},
},
}
RAMI benchmark scenarios#
We provide a specific loader for scenes derived from the
RAMI-V scene list.
These pre-configured are available for use and downloaded upon request via the
datastore.2We thank the DART team for allowing us to
use their 3D model files to derive our scene models. These are downloaded when a specific scenario is requested via the
datastore. Due to their size and the number of files they contain, the scenarios
are downloaded in a compressed format and, by default, extracted to the current
working directory. The extracted files are then used to load the scenario. To
change the default location for the extracted files, set the appropriate
parameter in the load_rami_scenario() function.
from pathlib import Path
import eradiate
from eradiate.experiments import CanopyExperiment
from eradiate.scenes.biosphere import load_rami_scenario
from eradiate.units import unit_registry as ureg
eradiate.set_mode("mono")
scenario_data = load_rami_scenario("HOM30_DIS_ED0")
scenario = CanopyExperiment(
**scenario_data,
measures={
"type": "perspective",
"film_resolution": (50, 50),
"origin": [10.0, 10.0, 10.0],
"target": [0.0, 0.0, 0.0],
"up": [0.0, 0.0, 1.0],
"sampler": "ldsampler",
"fov": 50.0,
"spp": 4**2,
"srf": {
"type": "multi_delta",
"wavelengths": np.array([660.0, 550.0, 440.0]) * ureg.nm,
},
},
illumination={"type": "directional", "zenith": 45.0, "azimuth": 350.0},
)
res_eradiate = eradiate.run(scenario)