Textures

Textures in Ignis are patterns, nodes or other building blocks for shading networks.

All number and color parameters can be connected to a shading network or texture via PExpr to build an actual tree. Cycles are prohibited.

A texture is specified in the textures block with a name and a type. The type has to be one of the textures listed at this section below.

{
    // ...
    "textures": [
        // ...
        {"name":"NAME", "type":"TYPE", /* DEPENDS ON TYPE */},
        // ...
    ]
    // ...
}

Image texture (image)

Parameter	Type	Default	PExpr	Description
filename	string	None		Path to a valid image file.
filter_type	string	"bicubic"		The filter type to be used. Has to be one of the following: [“bicubic”, “bilinear”, “nearest”].
wrap_mode	string	"repeat"		The wrap method to be used. Has to be one of the following: [“repeat”, “mirror”, “clamp”].
transform	transform	Identity		Optional 2d transformation applied to texture coordinates.
linear	boolean	false		The given image file is already in linear space and inverse gamma mapping can be skipped. Ignored for EXR and HDR images as it is expected that they are always in linear space.

Image texture

Nearest filter

Bilinear filter

Bicubic filter

Brick (brick)

Parameter	Type	Default	PExpr	Description
color0 color1	color	0, 1		The colors to used for the brick. color0 is the mortar, color1 is the actual brick.
scale_x scale_y	number	6, 3		Numbers of grids in a normalized frame [0,0]x[1,1].
gap_x gap_y	number	0.05, 0.1		Normalized gap size.
transform	transform	Identity		Optional 2d transformation applied to texture coordinates.

Brick texture

Checkerboard (checkerboard)

Parameter	Type	Default	PExpr	Description
color0 color1	color	0, 1		The colors to use in the checkerboard.
scale_x scale_y	number	2, 2		Numbers of grids in a normalized frame [0,0]x[1,1].
transform	transform	Identity		Optional 2d transformation applied to texture coordinates.

Checkerboard texture

Noise (noise)

Parameter	Type	Default	PExpr	Description
color	color	1		Tint
colored	boolean	false		True will generate a colored texture, instead of a grayscale one.

Noise texture, a slight color noise is visible

Interpolated Noise (pnoise)

Original noise used in legacy perlin implementation.

Parameter	Type	Default	PExpr	Description
color	color	1		Tint
colored	boolean	false		True will generate a colored texture, instead of a grayscale one.
scale_x scale_y	number	20, 20		Numbers of grids used for noise in a normalized frame [0,0]x[1,1].
transform	transform	Identity		Optional 2d transformation applied to texture coordinates.

PNoise texture

Cell Noise (cellnoise)

Parameter	Type	Default	PExpr	Description
color	color	1		Tint
colored	boolean	false		True will generate a colored texture, instead of a grayscale one.
scale_x scale_y	number	20, 20		Numbers of grids used for noise in a normalized frame [0,0]x[1,1].
transform	transform	Identity		Optional 2d transformation applied to texture coordinates.

Cell noise texture

Perlin Noise (perlin)

Parameter	Type	Default	PExpr	Description
color	color	1		Tint
colored	boolean	false		True will generate a colored texture, instead of a grayscale one.
scale_x scale_y	number	20, 20		Numbers of grids used for noise in a normalized frame [0,0]x[1,1].
transform	transform	Identity		Optional 2d transformation applied to texture coordinates.

Perlin noise texture

Voronoi Noise (voronoi)

Parameter	Type	Default	PExpr	Description
color	color	1		Tint
colored	boolean	false		True will generate a colored texture, instead of a grayscale one.
scale_x scale_y	number	20, 20		Numbers of grids used for noise in a normalized frame [0,0]x[1,1].
transform	transform	Identity		Optional 2d transformation applied to texture coordinates.

Voronoi texture

Fractional Brownian Motion (fbm)

Parameter	Type	Default	PExpr	Description
color	color	1		Tint
colored	boolean	false		True will generate a colored texture, instead of a grayscale one.
scale_x scale_y	number	20, 20		Numbers of grids used for noise in a normalized frame [0,0]x[1,1].
transform	transform	Identity		Optional 2d transformation applied to texture coordinates.

FBM texture

Expression (expr)

A custom PExpr expression with optional parameters.

Available are color (vec4), vector (vec3), number (num) and bool variables. The parameters used inside the expression have to be prefixed with color_, vec_, num_ and bool_ respectively.

E.g., color_tint will be called tint inside the expression.

Parameter	Type	Default	PExpr	Description
expr	string	None		A PExpr based expression

Custom texture generated by an expression

The following texture specification generates the above image.

{
    "type": "expr",
    "name": "tex",
    "color_tint_1": [0.8, 0.4, 0.6],
    "color_tint_2": [0.2, 0.1, 0.6],
    "expr": "perlin(20*uv)*select(cos(8*Pi*uv.x*uv.y)*sperlin(10*uv) < 0, tint_1, tint_2)"
}

Texture transform (transform)

Parameter	Type	Default	PExpr	Description
texture	color	None		The texture the transform is applied to.
transform	transform	Identity		2d transformation applied to texture coordinates.

Transformed texture as a texture