Three.js Shading Language

Creating shaders has always been an advanced step for most developers, many game creators have never created GLSL code from scratch. The shader graph solution adopted today by the industry has allowed developers more focused on dynamics to create the necessary graphic effects to meet the demands of their projects.

The aim of the project is to create an easy-to-use, even if for this we need to create complexity behind, this happened initially with Renderer and now with the TSL.

Other benefits that TSL brings besides simplifying shading creation is keeping the renderer agnostic, while all the complexity of a material can be imported into different modules and use tree shaking without breaking during the process.

A detail map makes things look more real in games. It adds tiny details like cracks or bumps to surfaces, like walls. In this example we will scale uv to improve details when seen up close and multiply with a base texture.

This is how we would achieve that using .onBeforeCompile():

const material=new THREE.MeshStandardMaterial();
material.map=colorMap;
material.onBeforeCompile=( shader )=> {

shader.uniforms.detailMap={ value: detailMap };

let token=’#define STANDARD’;

let insert=/* glsl */`
uniform sampler2D detailMap;
`;

shader.fragmentShader=shader.fragmentShader.replace( token, token + insert );

token=’#include ‘;

insert=/* glsl */`
diffuseColor *=texture2D( detailMap, vMapUv * 10.0 );
`;

shader.fragmentShader=shader.fragmentShader.replace( token, token + insert );

};

Any simple change from this makes the code increasingly complicated using .onBeforeCompile, the result we have today in the community is that we have countless types of parametric materials that do not communicate with each other, and that need to be updated periodically to be operating, limiting the creativity of modules to create unique materials in a simple way.

With TSL the code would look like this:

import { texture, uv } from ‘three/tsl’

const detail=texture( detailMap, uv().mul( 10 ) );

const material=new MeshStandardNodeMaterial();
material.colorNode=texture( colorMap ).mul( detail );

TSL is also capable of encoding code into different outputs such as WGSL/GLSL – WebGPU/WebGL, in addition to optimizing the shader graph automatically and through codes that can be inserted within each Node. This allows the developer to focus on productivity and leave the graphical management part to the Node System.

Another important feature of a graph shader is that we will no longer need to care about the sequence in which components are created, because the Node System will only declare and include it once.

Let’s say that you import positionWorld into your code, even if another component uses it, the calculations performed to obtain position world will only be performed once, as is the case with any other renderer component such as: normalWorld, modelPosition, etc.

All TSL component is created from a Node. The Node allows it to communicate with any other, value conversions can be automatic or manual, a Node can receive the output value expected by the parent Node and modify its own output snippet.

Since they are all components are extended from the Node class, it is possible to modulate them using tree shaking. In the shader construction process, the Node will have important information such as geometry, material, renderer as well as the backend, which can influence the type and value of output.

The build process is based on three pillars: setup, analyze and generate.

setup
Use TSL to create a completely customized code for the Node output. The Node can use many others within itself, have countless inputs, but there will always be a single output.

analyze
This proccess will check the nodes that were created in order to create useful information for generate the snippet, such as the need to create or not a cache/variable for optimizing a node.

generate
An output of string will be sent to each node independently, the node will also be able to create code in the flow, supporting multiple lines.

Node also have a native update process invoked by the update() function, these events be called by frame, render call and object draw.

It is also possible to serialize or deserialize a Node using serialize() and deserialize() functions.

Constants and explicit conversions

Input functions can be used to create contants and do explicit conversions.

Conversions are also performed automatically if the output and input are of different types.

Name
Returns a constant or convertion of type:

float( node | number )
float

int( node | number )
int

uint( node | number )
uint

bool( node | value )
boolean

color( node | hex | r,g,b )
color

vec2( node | Vector2 | x,y )
vec2

vec3( node | Vector3 | x,y,z )
vec3

vec4( node | Vector4 | x,y,z,w )
vec4

mat2( node | Matrix2 | a,b,c,d )
mat2

mat3( node | Matrix3 | a,b,c,d,e,f,g,h,i )
mat3

mat4( node | Matrix4 | a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p )
mat4

Advanced

ivec2( node | x,y )
ivec2

ivec3( node | x,y,z )
ivec3

ivec4( node | x,y,z,w )
ivec4

uvec2( node | x,y )
uvec2

uvec3( node | x,y,z )
uvec3

uvec4( node | x,y,z,w )
uvec4

bvec2( node | x,y )
bvec2

bvec3( node | x,y,z )
bvec3

bvec4( node | x,y,z,w )
bvec4

imat2( node | Matrix2 | a,b,c,d )
imat2

imat3( node | Matrix3 | a,b,c,d,e,f,g,h,i)
imat3

imat4( node | Matrix4 | a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p )
imat4

umat2( node | Matrix2 | a,b,c,d )
umat2

umat3( node | Matrix3 | a,b,c,d,e,f,g,h,i )
umat3

umat4( node | Matrix4 | a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p )
umat4

bmat2( node | Matrix2 | a,b,c,d )
bmat2

bmat3( node | Matrix3 | a,b,c,d,e,f,g,h,i )
bmat3

bmat4( node | Matrix4 | a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p )
bmat4

Example:

import { color, vec2, positionWorld } from ‘three/tsl’;

// constant
material.colorNode=color( 0x0066ff );

// conversion
material.colorNode=vec2( positionWorld ); // result positionWorld.xy

It is also possible to perform conversions using the method chain:

Name
Returns a constant or conversion of type:

.toFloat()
float

.toInt()
int

.toUint()
uint

.toBool()
boolean

.toColor()
color

.toVec2()
vec2

.toVec3()
vec3

.toVec4()
vec4

.toMat2()
mat2

.toMat3()
mat3

.toMat4()
mat4

Advanced

.toIvec2()
ivec2

.toIvec3()
ivec3

.toIvec4()
ivec4

.toUvec2()
uvec2

.toUvec3()
uvec3

.toUvec4()
uvec4

.toBvec2()
bvec2

.toBvec3()
bvec3

.toBvec4()
bvec4

.toImat2()
imat2

.toImat3()
imat3

.toImat4()
imat4

.toUmat2()
umat2

.toUmat3()
umat3

.toUmat4()
umat4

.toBmat2()
bmat2

.toBmat3()
bmat3

.toBmat4()
bmat4

Example:

import { positionWorld } from ‘three/tsl’;

// conversion
material.colorNode=positionWorld.toVec2(); // result positionWorld.xy

Method chaining will only be including operators, converters, math and some core functions. These functions, however, can be used on any node.

Example:

// it will invert the texture color
material.colorNode=texture( map ).rgb.oneMinus();

Swizzling is the technique that allows you to access, reorder, or duplicate the components of a vector using a specific notation within TSL. This is done by combining the identifiers:

const original=vec3( 1.0, 2.0, 3.0 ); // (x, y, z)
const swizzled=original.zyx; // swizzled=(3.0, 2.0, 1.0)

It’s possible use xyzw, rgba or stpq.

Name
Description

.add( node | value, … )
Return the addition of two or more value.

.sub( node | value )
Return the subraction of two or more value.

.mul( node | value )
Return the multiplication of two or more value.

.div( node | value )
Return the division of two or more value.

.assign( node | value )
Assign one or more value to a and return the same.

.remainder( node | value )
Computes the remainder of dividing the first node by the second.

.equal( node | value )
Checks if two nodes are equal.

.notEqual( node | value )
Checks if two nodes are not equal.

.lessThan( node | value )
Checks if the first node is less than the second.

.greaterThan( node | value )
Checks if the first node is greater than the second.

.lessThanEqual( node | value )
Checks if the first node is less than or equal to the second.

.greaterThanEqual( node | value )
Checks if the first node is greater than or equal to the second.

.and( node | value )
Performs logical AND on two nodes.

.or( node | value )
Performs logical OR on two nodes.

.not( node | value )
Performs logical NOT on a node.

.xor( node | value )
Performs logical XOR on two nodes.

.bitAnd( node | value )
Performs bitwise AND on two nodes.

.bitNot( node | value )
Performs bitwise NOT on a node.

.bitOr( node | value )
Performs bitwise OR on two nodes.

.bitXor( node | value )
Performs bitwise XOR on two nodes.

.shiftLeft( node | value )
Shifts a node to the left.

.shiftRight( node | value )
Shifts a node to the right.

const a=float( 1 );
const b=float( 2 );

const result=a.add( b ); // output: 3

It is possible to use classic JS functions or a tslFn() interface. The main difference is that tslFn() creates a controllable environment, allowing the use of stack where you can use assign and conditional, while the classic function only allows inline approaches.

Example:

// tsl function
const oscSine=tslFn( ( [ timer=timerGlobal ] )=> {

return timer.add( 0.75 ).mul( Math.PI * 2 ).sin().mul( 0.5 ).add( 0.5 );

} );

// inline function
export const oscSine=( timer=timerGlobal )=> timer.add( 0.75 ).mul( Math.PI * 2 ).sin().mul( 0.5 ).add( 0.5 );

Both above can be called with oscSin( value ).

TSL allows the entry of parameters as objects, this is useful in functions that have many optional arguments.

Example:

const oscSine=tslFn( ( { timer=timerGlobal } )=> {

return timer.add( 0.75 ).mul( Math.PI * 2 ).sin().mul( 0.5 ).add( 0.5 );

} );

const value=oscSine( { timer: value } );

If you want to use an export function compatible with tree shaking, remember to use /*@__PURE__*/

export const oscSawtooth=/*@__PURE__*/ tslFn( ( [ timer=timerGlobal ] )=> timer.fract() );

Name
Description

PI
The value of π (pi).

PI2
The value of 2π (two pi).

EPSION
A small value used to handle floating-point precision errors.

INFINITY
Represent infinity.

abs( x )
Return the absolute value of the parameter.

acos( x )
Return the arccosine of the parameter.

all( x )
Return true if all components of x are true.

any( x )
Return true if any component of x is true.

asin( x )
Return the arcsine of the parameter.

atan( x )
Return the arc-tangent of the parameters.

atan2( y, x )
Return the arc-tangent of the quotient of its arguments.

bitcast( x, y )
Reinterpret the bits of a value as a different type.

cbrt( x )
Return the cube root of the parameter.

ceil( x )
Find the nearest integer that is greater than or equal to the parameter.

clamp( x, min, max )
Constrain a value to lie between two further values.

cos( x )
Return the cosine of the parameter.

cross( x, y )
Calculate the cross product of two vectors.

dFdx( p )
Return the partial derivative of an argument with respect to x.

dFdy( p )
Return the partial derivative of an argument with respect to y.

degrees( radians )
Convert a quantity in radians to degrees.

difference( x, y )
Calculate the absolute difference between two values.

distance( x, y )
Calculate the distance between two points.

dot( x, y )
Calculate the dot product of two vectors.

equals( x, y )
Return true if x equals y.

exp( x )
Return the natural exponentiation of the parameter.

exp2( x )
Return 2 raised to the power of the parameter.

faceforward( N, I, Nref )
Return a vector pointing in the same direction as another.

floor( x )
Find the nearest integer less than or equal to the parameter.

fract( x )
Compute the fractional part of the argument.

fwidth( x )
Return the sum of the absolute derivatives in x and y.

inverseSqrt( x )
Return the inverse of the square root of the parameter.

invert( x )
Invert an alpha parameter ( 1. – x ).

length( x )
Calculate the length of a vector.

lengthSq( x )
Calculate the squared length of a vector.

log( x )
Return the natural logarithm of the parameter.

log2( x )
Return the base 2 logarithm of the parameter.

max( x, y )
Return the greater of two values.

min( x, y )
Return the lesser of two values.

mix( x, y, a )
Linearly interpolate between two values.

negate( x )
Negate the value of the parameter ( -x ).

normalize( x )
Calculate the unit vector in the same direction as the original vector.

oneMinus( x )
Return 1 minus the parameter.

pow( x, y )
Return the value of the first parameter raised to the power of the second.

pow2( x )
Return the square of the parameter.

pow3( x )
Return the cube of the parameter.

pow4( x )
Return the fourth power of the parameter.

radians( degrees )
Convert a quantity in degrees to radians.

reciprocal( x )
Return the reciprocal of the parameter (1/x).

reflect( I, N )
Calculate the reflection direction for an incident vector.

refract( I, N, eta )
Calculate the refraction direction for an incident vector.

round( x )
Round the parameter to the nearest integer.

saturate( x )
Constrain a value between 0 and 1.

sign( x )
Extract the sign of the parameter.

sin( x )
Return the sine of the parameter.

smoothstep( e0, e1, x )
Perform Hermite interpolation between two values.

sqrt( x )
Return the square root of the parameter.

step( edge, x )
Generate a step function by comparing two values.

tan( x )
Return the tangent of the parameter.

transformDirection( dir, matrix )
Transform the direction of a vector by a matrix and then normalize the result.

trunc( x )
Truncate the parameter, removing the fractional part.

const value=float( -1 );

// It’s possible use `value.abs()` too.
const positiveValue=abs( value ); // output: 1

Name
Description
Type

attribute( name, type=null, default=null )
Getting geometry attribute using name and type.
any

uv( index=0 )
UV attribute named uv + index.
vec2

vertexColor( index=0 )
Vertex color node for the specified index.
color

Name
Description
Type

positionGeometry
Position attribute of geometry.
vec3

positionLocal
Local variable for position.
vec3

positionWorld
World position.
vec3

positionWorldDirection
Normalized world direction.
vec3

positionView
View position.
vec3

positionViewDirection
Normalized view direction.
vec3

positionLocal represents the position after modifications made by skinning, morpher, etc.

Name
Description
Type

normalGeometry
Normal attribute of geometry.
vec3

normalLocal
Local variable for normal.
vec3

normalView
Normalized view normal.
vec3

normalWorld
Normalized world normal.
vec3

transformedNormalView
Transformed normal in view space.
vec3

transformedNormalWorld
Normalized transformed normal in world space.
vec3

transformedClearcoatNormalView
Transformed clearcoat normal in view space.
vec3

transformed* represents the normal after modifications made by skinning, morpher, etc.

Name
Description
Type

tangentGeometry
Tangent attribute of geometry.
vec4

tangentLocal
Local variable for tangent.
vec3

tangentView
Normalized view tangent.
vec3

tangentWorld
Normalized world tangent.
vec3

transformedTangentView
Transformed tangent in view space.
vec3

transformedTangentWorld
Normalized transformed tangent in world space.
vec3

Name
Description
Type

bitangentGeometry
Normalized bitangent in geometry space.
vec3

bitangentLocal
Normalized bitangent in local space.
vec3

bitangentView
Normalized bitangent in view space.
vec3

bitangentWorld
Normalized bitangent in world space.
vec3

transformedBitangentView
Normalized transformed bitangent in view space.
vec3

transformedBitangentWorld
Normalized transformed bitangent in world space.
vec3

Name
Description
Type

cameraNear
Near plane distance of the camera.
float

cameraFar
Far plane distance of the camera.
float

cameraLogDepth
Logarithmic depth value for the camera.
float

cameraProjectionMatrix
Projection matrix of the camera.
mat4

cameraProjectionMatrixInverse
Inverse projection matrix of the camera.
mat4

cameraViewMatrix
View matrix of the camera.
mat4

cameraWorldMatrix
World matrix of the camera.
mat4

cameraNormalMatrix
Normal matrix of the camera.
mat3

cameraPosition
World position of the camera.
vec3

Name
Description
Type

texture( texture, uv=uv(), level=null )
Retrieves texels from a texture.
vec4

cubeTexture( texture, uvw=reflectVector, level=null )
Retrieves texels from a cube texture.
vec4

triplanarTexture( textureX, textureY=null, textureZ=null, scale=float( 1 ), position=positionLocal, normal=normalLocal )
Computes texture using triplanar mapping based on provided parameters.
vec4

Name
Description
Type

modelDirection
Direction of the model.
vec3

modelViewMatrix
View matrix of the model.
mat4

modelNormalMatrix
Normal matrix of the model.
mat4

modelWorldMatrix
World matrix of the model.
mat4

modelPosition
Position of the model.
vec3

modelScale
Scale of the model.
vec3

modelViewPosition
View position of the model.
vec3

modelWorldMatrixInverse
Inverse world matrix of the model.
mat4

Name
Description
Type

reflectView
Computes reflection direction in view space.
vec3

reflectVector
Transforms the reflection direction to world space.
vec3

Name
Description
Type

matcapUV
UV coordinates for matcap material computation.
vec2

rotateUV( uv, rotation, centerNode=vec2( 0.5 ) )
Rotates UV coordinates around a center point.
vec2

spritesheetUV( count, uv=uv(), frame=float( 0 ) )
Computes UV coordinates for a sprite sheet based on the number of frames, UV coordinates, and frame index.
vec2

equirectUV( direction=positionWorldDirection )
Computes UV coordinates for equirectangular mapping based on the direction vector.
vec2

Variable
Description
Type

remap
Remaps a value from one range to another.
any

remapClamp
Remaps a value from one range to another, with clamping.
any

Variable
Description
Type

hash( seed )
Generates a hash value in the range [ 0, 1 ] from the given seed.
float

range( min, max )
Generates a range attribute of values between min and max.
any

Variable
Description
Type

oscSine( timer=timerGlobal )
Generates a sine wave oscillation based on a timer.
float

oscSquare( timer=timerGlobal )
Generates a square wave oscillation based on a timer.
float

oscTriangle( timer=timerGlobal )
Generates a triangle wave oscillation based on a timer.
float

oscSawtooth( timer=timerGlobal )
Generates a sawtooth wave oscillation based on a timer.
float

Variable
Description
Type

directionToColor( value )
Converts direction vector to color.
color

colorToDirection( value )
Converts color to direction vector.
vec3

To create a variable from a node use .toVar().

The first parameter is used to add a name to it, otherwise the node system will name it automatically, it can be useful in debugging or access using wgslFn.

const uvScaled=uv().mul( 10 ).toVar();

material.colorNode=texture( map, uvScaled );

varying( node, name=null )

Let’s suppose you want to optimize some calculation in the vertex stage but are using it in a slot like material.colorNode.

For example:

// multiplication will be executed in vertex stage
const normalView=varying( modelNormalMatrix.mul( normalLocal ) );

// normalize will be executed in fragment stage
// because .colorNode is fragment stage slot as default
material.colorNode=normalView.normalize();

The first parameter of varying modelNormalMatrix.mul( normalLocal ) will be executed in vertex stage, and the return from varying() will be a varying as we are used in WGSL/GLSL, this can optimize extra calculations in the fragment stage. The second parameter allows you to add a custom name to varying.

If varying() is added only to .positionNode, it will only return a simple variable and varying will not be created.