Texture¶

In 3D data visualization, texture defines the mapping from a 3D element to colors or values.

Uniform texture¶

Uniform texture maps all 3D elements to the same value.

t = hkw.texture.Uniform(color="ivory")

Image texture¶

Image texture maps a 3D element to color based on the UV coordinates and an image texture.

t = hkw.texture.Image(uv="uv_attr_name", filename="texture.png")

Field	Type	Meaning
`filename`	PathLike	Path to the image file
`uv`	AttributeLike \| None	UV attribute (auto-detected if None)
`raw`	bool	Treat texture as linear (no sRGB decode). Set `True` for normal maps and other non-color data. Default `False`.
`saturation`	float	Saturation multiplier. `1.0` = full color, `0.0` = grayscale. Default `1.0`.
`whiteness`	float	Blend toward pure white. `0.0` = original color, `1.0` = pure white. Default `0.0`.

# Desaturate and brighten an image texture.
t = hkw.texture.Image(
    filename="texture.png",
    uv="uv_attr",
    saturation=0.5,
    whiteness=0.2,
)

Scalar field texture¶

One of the most common use case of texture is to map a scalar field to a color field.

Field	Type	Meaning
data	AttributeLike	The attribute defining the scalar field
colormap	str	The colormap to use
domain	tuple	The domain of the attribute
range	tuple	The range of colormap
categories	bool	Whether the data represents categories (i.e. discrete values)

t = hkw.texture.ScalarField(data="attr_name")

See the Heat Method and the Components examples for application of the scalar field texture.

Checkerboard texture¶

CheckerBoard texture maps 3D elements to one of two possible sub-textures based on a checkerboard pattern.

t = hkw.texture.CheckBoard(
    uv="uv_attr_name",
    texture1=hkw.texture.Uniform(color=0.2),
    texture2=hkw.texture.Uniform(color=0.8),
)

Isocontour texture¶

Isocontour texture maps 3D elements to one of two possible sub-textures based on the iso-contour of a given scalar field.

t = hkw.texture.Isocontour(
    data="attr_name",
    ratio=0.2,
    texture1=hkw.texture.Uniform(color=0.2),
    texture2=hkw.texture.Uniform(color=0.8),
)

See the Heat Method example for an application of the isocontour texture.