doc.go

/*
Package texture contains functions that can be combined to create textures.

Three types of texture field are supported, value fields which return a value in the range [-1,1]; vector
fields that typically return a triplet of values; and color fields which return a Color from the standard
color package.

All fields provide an Eval2(x, y float64) function which takes any x and y and
returns either a value, vector or color. If a type doesn't support the entire 2D plane, then it must return 0,
{0, ..., 0}, or color.Black for values of x and y not supported.

1D Generators (have a wavelength, center offset, phase, angle):

	Flat - produces a flat field
	NL1 - produces a wave using a NonLinear function (reflected)
	NL2 - produces a wave using two NonLinear functions, one for up and the other for down
	Noise1D - produces a wave derived from the Perlin noise function
	Saw - produces a saw wave
	Sin - produces a Sine wave
	Square - produces a square wave
	Triangle - produces a triangular wave

1D Random/Multiple wavelength versions of the above

2D Generators:

	Box - one value if inside box or another if not
	NonLinear - produces a field filled with circles/elipses using a non-linear function
	Image - produces a field using an input image (converted to Gray16)
	Perlin - produces a field using Ken Perlin's improved noise function
	Triangles - produces a field filled with triangles
	BlinnField - produces a field filled with metaballs
	WorleyField - produces a field filled with Worley cells

1D Filters map [-1,1] to [-1,1] (with A, B and C):

	Abs
	Clip
	Fold
	Gaussian
	Pow
	Quantize - quantizes into C buckets
	Sine

2D Combiners mix two or more source fields (rescaled to fit):

	ColorBlend - uses the value source to blend between to color sources
	ColorFields - uses four value sources to populate a color field (RGBA or HSLA)
	ColorSubstitute - switches between two color fields based on the values in a value field
	Combiner2
	  Add - sum of two sources
	  Avg - sum of two sources
	  Diff - weighted sum of two sources based on their difference
	  Max - max of two sources
	  Min - min of two sources
	  Mul - product of two sources
	  Sub - difference of two sources (s1 - s2)
	Combiner3
	  Substitute - substitute one value for another depending on a third value
	Displace - source displaced by X and Y scaled sources
	Window2 - select between two sources based on a region

2D Other:

	Distort - similar to Displace only the field itself is used as the displacement source
	Fractal - combine a source field through an affine transform multiple times
	IFS - combine a source field through an affine transform multiple times
	Transform - transforms a value field's X and Y with an Aff3 affine transform
	TransformCF - transforms a color field's X and Y with an Aff3 affine transform
	TransformVF - transforms a vector field's X and Y with an Aff3 affine transform
	UnitNormal - converts a vector field to a unit length vector field
	Window - window the source field to a region

Converters:

	Color - converts a value field to a gray scale color field
	ColorConv - converts a value field to a color field using a non-linear color map
	ColorSinCos - converts a value field to a color field using sin and cos
	ColorVector - converts a vector field to a color field (RGB or HSL)
	Normal - converts a value field to a vector field using the finite difference method
	Select - selects one component of a vector field as a value field
	VectorCombine - combines the components of a vector field into a value field

Generators available from other contributors:

	OpenSimplex - github.com/ojrac/opensimplex-go
*/
package texture