Materials

Every voxel in Shape-Z is shaded with a Disney Principled BSDF material.
You define a material once and then reference it anywhere in your shapes or patterns.

material Rock {
    albedo    { … }
    roughness { … }
    …
}

A material block is just a collection of parameter sub-blocks—each one returns either a float or a vec3 colour.
Inside those blocks you can use any Shape-Z expression, including helper functions, noise, and the special hash value that comes from the caller (e.g. a pattern or noise field).

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Supported Disney BSDF parameters

Parameter	Type	Range	What it controls
albedo	vec3	0-1	Base diffuse / base-colour
subsurface	float	0-1	Soft, waxy subsurface scattering
metallic	float	0-1	0 = dielectric, 1 = perfect metal
specular_tint	float	0-1	Tints the specular lobe towards the albedo hue
roughness	float	0-1	Micro-surface roughness; lower = sharper highlights
anisotropic	float	0-1	Highlight stretching (e.g. brushed metal)
sheen	float	0-1	Velvet-like retro-reflection on grazing angles
sheen_tint	float	0-1	Tints the sheen towards the albedo
clearcoat	float	0-1	Extra clear-coat layer on top (car paint)
clearcoat_gloss	float	0-1	Roughness of that clear-coat layer
ior	float	≥1	Index of refraction for dielectrics
transmission	float	0-1	Glass-like transparency; enables volumetric shading
emission	vec3	any	Self-emitted light (makes voxels glow)

tip

Parameters you leave out default to physically sensible values (e.g. metallic = 0, roughness = 0.5, …).

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Example

material Rock {
    // Slightly varied, desaturated pinkish base colour
    albedo {
        mix(vec3(0.70, 0.45, 0.50),
            vec3(0.60, 0.60, 0.65),
            hash);
    }

    // Semi-glossy surface with per-voxel variation
    roughness { 0.2 + (hash - 0.5) * 0.2; }

    // A metallic, tinted stone with a subtle clear-coat
    metallic        { 1.0; }
    specular_tint   { 0.2 + (hash - 0.5) * 0.2; }
    clearcoat       { 0.3 + (hash - 0.5) * 0.2; }
    clearcoat_gloss { 0.8 + (hash - 0.5) * 0.15; }
}

• hash is a uniform value (0-1) supplied by the pattern or noise that applied the material, giving you easy per-voxel variation without extra random calls.
• Because transmission is not set the material stays opaque; adding a transmission { … } block automatically flags it as volumetric so Shape-Z’s renderer can handle refraction and absorption.

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Practical notes

• Stay in the physical range (0-1 for most floats) for predictable lighting.
• Emission is evaluated in linear colour space—use realistic luminance (e.g. vec3(5.0) for a bright LED).
• Materials are lightweight; create as many as you need.
• Reuse materials across files by placing them in a shared .shpz and import-ing it.

That’s all you need to craft anything from dull concrete to shimmering glass within Shape-Z.

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Volumetric Mediums

In addition to surface parameters, a material can define a medium sub‑block that controls how light behaves inside the volume—perfect for water, fog, glass, or flames.

material WaterMedium {
    medium Absorb {
        color   { vec3(0.0, 0.6, 0.5); } // absorption tint
        density { 0.5; }                // strength of absorption
    }
}

Supported medium types

Medium	Purpose	Required fields
Absorb	Pure absorption/attenuation—tinted glass, murky water	color, density
Emissive	Participating medium that adds light—flames, plasma	color, intensity
Scatter	Isotropic scattering—mist, fog, smoke	color, density, (optional) anisotropy

tip

A material becomes volumetric as soon as it contains a medium block or sets transmission.

• Density scales the effect strength; higher values mean stronger absorption or scattering over the same distance.
• Media are evaluated per‑ray segment inside the voxel, so thin objects may appear almost clear while thick volumes show the full effect.
• Combine multiple media by layering materials (e.g. glowing fog inside tinted glass) for complex visuals.