render.material.Material

render.material.Material(
    name=None,
    color=None,
    roughness=0.5,
    metallic=0.0,
    opacity=1.0,
    ior=1.0,
    reflectivity=0.0,
    *,
    density=None,
    conductivity=None,
    specific_heat=None,
    youngs_modulus=None,
    poisson_ratio=None,
    thermal_expansion=None,
    yield_strength=None,
    free=False,
)

Material properties for physically-inspired shading and simulation.

Properties use the same Parameter containers as SDF primitives so material assignment, CSG blending and optimization share one consistent representation. Optical properties always have a value; physical ones default to None (“not specified”) and are carried as NaN in the array representation.

Parameters

Name	Type	Description	Default
name	str | None	Material name, used to derive parameter names when free=True (e.g. "bumper_mat" → "bumper_mat_color", …). Optional when all properties are already Parameter objects.	None
color		RGB surface color, values in [0, 1].	None
roughness	float	Surface roughness, 0 = mirror, 1 = fully diffuse.	0.5
metallic	float	Metallic factor; 0 = dielectric, 1 = metallic specular.	0.0
opacity	float	Opacity; 0 = fully transparent, 1 = fully opaque.	1.0
ior	float	Index of refraction; 1.0 = air, 1.33 = water, 1.5 = glass.	1.0
reflectivity	float	Mirror reflectivity; 0 = fully diffuse, 1 = perfect mirror.	0.0
density	float | None	Mass density in kg/m^3 (mass reporting, self-weight loads, mass regularizers).	None
conductivity	float | None	Thermal conductivity in W/(m*K).	None
specific_heat	float | None	Specific heat capacity in J/(kg*K) (carried for transient studies; steady-state solves ignore it).	None
youngs_modulus	float | None	Young’s modulus in Pa.	None
poisson_ratio	float | None	Poisson ratio, dimensionless, in [0, 0.5).	None
thermal_expansion	float | None	Linear coefficient of thermal expansion in 1/K.	None
yield_strength	float | None	Yield strength in Pa (drives the safety-factor post-process on elastic results).	None
free	bool	If True, wrap the specified raw values as free Parameters with sensible bounds. Unspecified physical properties stay fixed (a free NaN is meaningless), and already-constructed Parameter objects are left unchanged. Requires name.	False

Example::

body_mat = Material(color=[0.5, 0.5, 0.5], roughness=0.4,
                    metallic=0.12, density=2700.0,
                    conductivity=167.0, youngs_modulus=68.9e9,
                    poisson_ratio=0.33)

Methods

Name	Description
as_dict	Return material properties as a JAX-pytree-compatible dict of arrays.
blend	Linearly interpolate between two material dicts.
describe	JSON-ready payload of every property, for the viewer’s inspector.
get	Concrete value of one property, or None when unspecified.

as_dict

render.material.Material.as_dict()

Return material properties as a JAX-pytree-compatible dict of arrays.

Every optical and physical property is present, always with the same keys, so the dict has one static structure across a whole scene. Unspecified physical properties read as NaN.

blend

render.material.Material.blend(m1, m2, t)

Linearly interpolate between two material dicts.

Physical properties blend exactly like optical ones, which is what makes a smooth CSG interface a smooth property interface (and hence differentiable w.r.t. the geometry that moves it). An unspecified (NaN) property stays unspecified through the blend.

Parameters

Name	Type	Description	Default
m1	dict	First material dict.	required
m2	dict	Second material dict.	required
t	Array	Blend factor; t=1 returns m1, t=0 returns m2.	required

describe

render.material.Material.describe()

JSON-ready payload of every property, for the viewer’s inspector.

Returns

Name	Type	Description
	dict[str, Any]	A dict with the optical properties inline (color as a
	dict[str, Any]	three-float list, the rest as floats), a physical map whose
	dict[str, Any]	values are floats or None where the material does not specify
	dict[str, Any]	them, a units map naming the SI unit of each physical
	dict[str, Any]	property, and a free map flagging which properties are
	dict[str, Any]	optimizer-controlled.

get

render.material.Material.get(key)

Concrete value of one property, or None when unspecified.

Parameters

Name	Type	Description	Default
key	str	Property name (optical or physical).	required

Returns

Name	Type	Description
	float | None	float for scalar properties, list[float] for color, and
	float | None	None for a physical property this material does not specify.