Albedo sources¶

Chosen by "type" in source.

Type	What it is
`synthetic`	A base colour in hue, saturation and value, each varied by noise: an albedo for terrain without data.
`raster`	Albedo read from one or three bands of a GeoTIFF in the terrain's projection, such as an orbital albedo map.

`synthetic`¶

A base colour in hue, saturation and value, each varied by noise: an albedo for terrain without data.

Key	Type	Default	Range	Unit	Description
`rgb`	boolean	`false`			Gives three bands, red, green and blue, from the colour; off gives one band of the value alone, ignoring hue and saturation.
`hue`	number	`0.0`		deg	Hue of the base colour in degrees, wrapping around; used with rgb only.
`saturation`	number	`0.0`	[0, 1]		Saturation of the base colour, from 0 for grey to 1; used with rgb only.
`value`	number	`0.11`	[0, 1]		Reflectance of the brightest band, from 0 to 1; the one band's value without rgb. Higher values give a brighter surface.

hue_noise[]: Noise layers, 0 to 8, whose sum in degrees is added to the hue; used with rgb only.

Key	Type	Default	Range	Unit	Description
`enabled`	boolean	`true`			Includes this layer in the stack; disabled layers are skipped.
`basis`	one of `perlin`, `simplex`, `value`, `worley_f1`, `worley_f2`, `worley_f2_minus_f1`, `voronoi`	`"perlin"`			Single-octave noise the fractal is built from.
`fractal`	one of `fbm`, `ridged`, `billow`, `hybrid_multifractal`	`"fbm"`			How the octaves of the basis noise are combined.
`blend`	one of `add`, `max`, `min`, `mask`	`"add"`			How this layer combines with the height of the layers before it; the first enabled layer sets the height instead.
`seed`	integer	`0`			Seed of the noise; changing it gives a different pattern of the same character.
`wavelength`	number	`1000.0`	(0, inf)	m	Wavelength of the first, broadest octave, in metres; sets the size of the largest features.
`amplitude`	number	`100.0`		m	Largest height of the layer above or below 0, in metres.
`octaves`	integer	`8`	[1, 32]		Number of octaves, at least 1; each one adds detail at a shorter wavelength.
`lacunarity`	number	`2.0`	(1, inf)		Frequency ratio between successive octaves; greater than 1.
`gain`	number	`0.5`	(0, inf)		Weight ratio between successive octaves, greater than 0; higher values give rougher terrain. Unused when the Hurst exponent is set.
`hurst`	number, optional	`null`			Hurst exponent that sets the octave gain to lacunarity^-hurst: near 1 is smooth, lower is rougher at short baselines. Unset uses the gain.
`offset`	number	`1.0`	(0, inf)		Ridge offset of the ridged and hybrid multifractal types; greater than 0.
`warp_amplitude`	number	`0.0`	[0, inf)	m	Domain warp displacement in metres, which bends the noise into swirled shapes; 0 disables warping.
`warp_wavelength`	number	`500.0`	(0, inf)	m	Wavelength of the warp field, in metres.

saturation_noise[]: Noise layers, 0 to 8, added to the saturation, which is then clamped to [0, 1]; used with rgb only.

Key	Type	Default	Range	Unit	Description
`enabled`	boolean	`true`			Includes this layer in the stack; disabled layers are skipped.
`basis`	one of `perlin`, `simplex`, `value`, `worley_f1`, `worley_f2`, `worley_f2_minus_f1`, `voronoi`	`"perlin"`			Single-octave noise the fractal is built from.
`fractal`	one of `fbm`, `ridged`, `billow`, `hybrid_multifractal`	`"fbm"`			How the octaves of the basis noise are combined.
`blend`	one of `add`, `max`, `min`, `mask`	`"add"`			How this layer combines with the height of the layers before it; the first enabled layer sets the height instead.
`seed`	integer	`0`			Seed of the noise; changing it gives a different pattern of the same character.
`wavelength`	number	`1000.0`	(0, inf)	m	Wavelength of the first, broadest octave, in metres; sets the size of the largest features.
`amplitude`	number	`100.0`		m	Largest height of the layer above or below 0, in metres.
`octaves`	integer	`8`	[1, 32]		Number of octaves, at least 1; each one adds detail at a shorter wavelength.
`lacunarity`	number	`2.0`	(1, inf)		Frequency ratio between successive octaves; greater than 1.
`gain`	number	`0.5`	(0, inf)		Weight ratio between successive octaves, greater than 0; higher values give rougher terrain. Unused when the Hurst exponent is set.
`hurst`	number, optional	`null`			Hurst exponent that sets the octave gain to lacunarity^-hurst: near 1 is smooth, lower is rougher at short baselines. Unset uses the gain.
`offset`	number	`1.0`	(0, inf)		Ridge offset of the ridged and hybrid multifractal types; greater than 0.
`warp_amplitude`	number	`0.0`	[0, inf)	m	Domain warp displacement in metres, which bends the noise into swirled shapes; 0 disables warping.
`warp_wavelength`	number	`500.0`	(0, inf)	m	Wavelength of the warp field, in metres.

value_noise[]: Noise layers, 0 to 8: the value is multiplied by 1 plus their sum and clamped to [0, 1], so their amplitude sets the relative contrast.

Key	Type	Default	Range	Unit	Description
`enabled`	boolean	`true`			Includes this layer in the stack; disabled layers are skipped.
`basis`	one of `perlin`, `simplex`, `value`, `worley_f1`, `worley_f2`, `worley_f2_minus_f1`, `voronoi`	`"perlin"`			Single-octave noise the fractal is built from.
`fractal`	one of `fbm`, `ridged`, `billow`, `hybrid_multifractal`	`"fbm"`			How the octaves of the basis noise are combined.
`blend`	one of `add`, `max`, `min`, `mask`	`"add"`			How this layer combines with the height of the layers before it; the first enabled layer sets the height instead.
`seed`	integer	`0`			Seed of the noise; changing it gives a different pattern of the same character.
`wavelength`	number	`1000.0`	(0, inf)	m	Wavelength of the first, broadest octave, in metres; sets the size of the largest features.
`amplitude`	number	`100.0`		m	Largest height of the layer above or below 0, in metres.
`octaves`	integer	`8`	[1, 32]		Number of octaves, at least 1; each one adds detail at a shorter wavelength.
`lacunarity`	number	`2.0`	(1, inf)		Frequency ratio between successive octaves; greater than 1.
`gain`	number	`0.5`	(0, inf)		Weight ratio between successive octaves, greater than 0; higher values give rougher terrain. Unused when the Hurst exponent is set.
`hurst`	number, optional	`null`			Hurst exponent that sets the octave gain to lacunarity^-hurst: near 1 is smooth, lower is rougher at short baselines. Unset uses the gain.
`offset`	number	`1.0`	(0, inf)		Ridge offset of the ridged and hybrid multifractal types; greater than 0.
`warp_amplitude`	number	`0.0`	[0, inf)	m	Domain warp displacement in metres, which bends the noise into swirled shapes; 0 disables warping.
`warp_wavelength`	number	`500.0`	(0, inf)	m	Wavelength of the warp field, in metres.

Every key with its default

{
    "type": "synthetic",
    "rgb": false,
    "hue": 0.0,
    "saturation": 0.0,
    "value": 0.11,
    "hue_noise": [],
    "saturation_noise": [],
    "value_noise": []
}

Used in: example_albedo_blast_zone, example_albedo_crater_rays, example_albedo_fresh_crater, example_albedo_moon_site, example_albedo_new_crater, example_albedo_oblique_rays, example_albedo_rgb, example_albedo_rocks_and_slopes and 2 more

`raster`¶

Albedo read from one or three bands of a GeoTIFF in the terrain's projection, such as an orbital albedo map.

Key	Type	Default	Description
`path`	string	`""`	GeoTIFF albedo map in the terrain's projected coordinates; relative paths resolve against the configuration's folder.
`bands`	list of integer	`[...]`	Bands of the file to read, counting from 0: one for a single albedo band, or three for red, green and blue.
`scale`	number, optional	`null`	Factor each sample is multiplied by, replacing the band's scale from the file's GDAL metadata, as for maps stored as integers. Unset keeps the file's.
`offset`	number, optional	`null`	Added to each scaled sample, replacing the band's offset from the file's GDAL metadata. Unset keeps the file's.
`resampling`	one of `nearest`, `bilinear`, `cubic`	`"cubic"`	Interpolation used to sample the map at the terrain's points.

detail: Fractal detail below the map's resolution, continuing the map's own measured roughness to finer scales.

Key	Type	Default	Range	Description
`enabled`	boolean	`true`		Adds fractal detail below the map's resolution; off leaves the interpolated map as it is.
`seed`	integer	`0`		Seed of the detail noise; changing it gives a different pattern of the same roughness.
`octaves`	integer	`4`	[1, 16]	Octaves of detail, 1 to 16, from half the map's cell size down, each half the wavelength of the one before.
`scale`	number	`1.0`	[0, inf)	Factor on the RMS of every octave, not negative; 0 adds no detail, higher values give a more mottled albedo.
`hurst`	number, optional	`null`	[0, 1]	Hurst exponent, in [0, 1], used instead of the one measured from the map; lower values keep more contrast at fine scales. Unset uses the measured one.

fade: How octaves of detail too fine for the sample spacing fade out.

Key	Type	Default	Range	Description
`start_samples`	number	`2.0`	[0, inf)	Samples across a feature's diameter up to which it is left out entirely.
`end_samples`	number	`4.0`	(0, inf)	Samples across a feature's diameter from which it is applied in full; it fades in between the two counts.
`shape`	one of `linear`, `smoothstep`, `smootherstep`, `gaussian`	`"smoothstep"`		Curve of the fade between the start and end sample counts.

Every key with its default

{
    "type": "raster",
    "path": "",
    "bands": [
        0
    ],
    "scale": null,
    "offset": null,
    "resampling": "cubic",
    "detail": {
        "enabled": true,
        "seed": 0,
        "octaves": 4,
        "scale": 1.0,
        "hurst": null,
        "fade": {
            "start_samples": 2.0,
            "end_samples": 4.0,
            "shape": "smoothstep"
        }
    }
}

Albedo sources¶

synthetic¶

raster¶

`synthetic`¶

`raster`¶