Accueil / npm / three@0.186.1 / examples / jsm / tsl / display / SSSNode.js
SSSNode.js
import { RedFormat, RenderTarget, Vector2, RendererUtils, QuadMesh, TempNode, NodeMaterial, NodeUpdateType, UnsignedByteType } from 'three/webgpu';
import { reference, viewZToPerspectiveDepth, logarithmicDepthToViewZ, getScreenPosition, getViewPosition, float, Break, Loop, int, max, abs, If, interleavedGradientNoise, screenCoordinate, Fn, passTexture, uv, uniform, perspectiveDepthToViewZ, orthographicDepthToViewZ, vec2, lightPosition, lightTargetPosition, fract, rand, mix, context } from 'three/tsl';
const _quadMesh = /*@__PURE__*/ new QuadMesh();
const _size = /*@__PURE__*/ new Vector2();
const _spatialOffsets = [ 0, 0.5, 0.25, 0.75 ];
let _rendererState;
/**
* Post processing node for applying Screen-Space Shadows (SSS) to a scene.
*
* Screen-Space Shadows (also known as Contact Shadows) should ideally be used to complement
* traditional shadow maps. They are best suited for rendering detailed shadows of smaller
* objects at a closer scale like intricate shadowing on highly detailed models. In other words:
* Use Shadow Maps for the foundation and Screen-Space Shadows for the details.
*
* The shadows produced by this implementation might have too hard edges for certain use cases.
* Use a box, gaussian or hash blur to soften the edges before doing the composite with the
* beauty pass. Code example:
*
* ```js
* const sssPass = sss( scenePassDepth, camera, mainLight );
*
* const sssBlur = boxBlur( sssPass.r, { size: 2, separation: 1 } ); // optional blur
* ```
*
* Limitations:
*
* - Ideally the maximum shadow length should not exceed `1` meter. Otherwise the effect gets
* computationally very expensive since more samples during the ray marching process are evaluated.
* You can mitigate this issue by reducing the `quality` parameter.
* - The effect can only be used with a single directional light, the main light of your scene.
* This main light usually represents the sun or daylight.
* - Like other Screen-Space techniques SSS can only honor objects in the shadowing computation that
* are currently visible within the camera's view.
*
* References:
* - {@link https://panoskarabelas.com/posts/screen_space_shadows/}.
* - {@link https://www.bendstudio.com/blog/inside-bend-screen-space-shadows/}.
*
* @augments TempNode
* @three_import import { sss } from 'three/addons/tsl/display/SSSNode.js';
*/
class SSSNode extends TempNode {
static get type() {
return 'SSSNode';
}
/**
* Constructs a new SSS node.
*
* @param {TextureNode} depthNode - A texture node that represents the scene's depth.
* @param {Camera} camera - The camera the scene is rendered with.
* @param {DirectionalLight} mainLight - The main directional light of the scene.
*/
constructor( depthNode, camera, mainLight ) {
super( 'float' );
/**
* A node that represents the beauty pass's depth.
*
* @type {TextureNode}
*/
this.depthNode = depthNode;
/**
* Maximum shadow length in world units. Longer shadows result in more computational
* overhead.
*
* @type {UniformNode<float>}
* @default 0.1
*/
this.maxDistance = uniform( 0.1, 'float' );
/**
* Depth testing thickness.
*
* @type {UniformNode<float>}
* @default 0.01
*/
this.thickness = uniform( 0.01, 'float' );
/**
* Shadow intensity. Must be in the range `[0, 1]`.
*
* @type {UniformNode<float>}
* @default 1.0
*/
this.shadowIntensity = uniform( 1.0, 'float' );
/**
* This parameter controls how detailed the raymarching process works.
* The value ranges is `[0,1]` where `1` means best quality (the maximum number
* of raymarching iterations/samples) and `0` means no samples at all.
*
* A quality of `0.5` is usually sufficient for most use cases. Try to keep
* this parameter as low as possible. Larger values result in noticeable more
* overhead.
*
* @type {UniformNode<float>}
* @default 0.5
*/
this.quality = uniform( 0.5 );
/**
* The resolution scale. Valid values are in the range
* `[0,1]`. `1` means best quality but also results in
* more computational overhead. Setting to `0.5` means
* the effect is computed in half-resolution.
*
* @type {number}
* @default 1
*/
this.resolutionScale = 1;
/**
* Whether to use temporal filtering or not. Setting this property to
* `true` requires the usage of `TRAANode`. This will help to reduce noise
* although it introduces typical TAA artifacts like ghosting and temporal
* instabilities.
*
* @type {boolean}
* @default false
*/
this.useTemporalFiltering = false;
/**
* The `updateBeforeType` is set to `NodeUpdateType.FRAME` since the node renders
* its effect once per frame in `updateBefore()`.
*
* @type {string}
* @default 'frame'
*/
this.updateBeforeType = NodeUpdateType.FRAME;
// private uniforms
/**
* Represents the view matrix of the scene's camera.
*
* @private
* @type {UniformNode<mat4>}
*/
this._cameraViewMatrix = uniform( camera.matrixWorldInverse );
/**
* Represents the projection matrix of the scene's camera.
*
* @private
* @type {UniformNode<mat4>}
*/
this._cameraProjectionMatrix = uniform( camera.projectionMatrix );
/**
* Represents the inverse projection matrix of the scene's camera.
*
* @private
* @type {UniformNode<mat4>}
*/
this._cameraProjectionMatrixInverse = uniform( camera.projectionMatrixInverse );
/**
* Represents the near value of the scene's camera.
*
* @private
* @type {ReferenceNode<float>}
*/
this._cameraNear = reference( 'near', 'float', camera );
/**
* Represents the far value of the scene's camera.
*
* @private
* @type {ReferenceNode<float>}
*/
this._cameraFar = reference( 'far', 'float', camera );
/**
* The resolution of the pass.
*
* @private
* @type {UniformNode<vec2>}
*/
this._resolution = uniform( new Vector2() );
/**
* Temporal offset added to the initial ray step.
*
* @private
* @type {UniformNode<float>}
*/
this._temporalOffset = uniform( 0 );
/**
* The frame ID use when temporal filtering is enabled.
*
* @private
* @type {UniformNode<uint>}
*/
this._frameId = uniform( 0 );
/**
* A reference to the scene's main light.
*
* @private
* @type {DirectionalLight}
*/
this._mainLight = mainLight;
/**
* The camera the scene is rendered with.
*
* @private
* @type {Camera}
*/
this._camera = camera;
/**
* The render target the SSS is rendered into.
*
* @private
* @type {RenderTarget}
*/
this._sssRenderTarget = new RenderTarget( 1, 1, { depthBuffer: false, format: RedFormat, type: UnsignedByteType } );
this._sssRenderTarget.texture.name = 'SSS';
/**
* The material that is used to render the effect.
*
* @private
* @type {NodeMaterial}
*/
this._material = new NodeMaterial();
this._material.name = 'SSS';
/**
* The result of the effect is represented as a separate texture node.
*
* @private
* @type {PassTextureNode}
*/
this._textureNode = passTexture( this, this._sssRenderTarget.texture );
}
/**
* Returns the result of the effect as a texture node.
*
* @return {PassTextureNode} A texture node that represents the result of the effect.
*/
getTextureNode() {
return this._textureNode;
}
/**
* Sets the size of the effect.
*
* @param {number} width - The width of the effect.
* @param {number} height - The height of the effect.
*/
setSize( width, height ) {
width = Math.round( this.resolutionScale * width );
height = Math.round( this.resolutionScale * height );
this._resolution.value.set( width, height );
this._sssRenderTarget.setSize( width, height );
}
/**
* This method is used to render the effect once per frame.
*
* @param {NodeFrame} frame - The current node frame.
*/
updateBefore( frame ) {
const { renderer } = frame;
_rendererState = RendererUtils.resetRendererState( renderer, _rendererState );
//
const size = renderer.getDrawingBufferSize( _size );
this.setSize( size.width, size.height );
// update temporal uniforms
if ( this.useTemporalFiltering === true ) {
const frameId = frame.frameId;
this._temporalOffset.value = _spatialOffsets[ frameId % 4 ];
this._frameId = frame.frameId;
} else {
this._temporalOffset.value = 0;
this._frameId = 0;
}
//
_quadMesh.material = this._material;
_quadMesh.name = 'SSS';
// clear
renderer.setClearColor( 0xffffff, 1 );
// sss
renderer.setRenderTarget( this._sssRenderTarget );
_quadMesh.render( renderer );
// restore
RendererUtils.restoreRendererState( renderer, _rendererState );
}
/**
* This method is used to setup the effect's TSL code.
*
* @param {NodeBuilder} builder - The current node builder.
* @return {PassTextureNode}
*/
setup( builder ) {
const uvNode = uv();
const getViewZ = Fn( ( [ depth ] ) => {
let viewZNode;
if ( this._camera.isPerspectiveCamera ) {
viewZNode = perspectiveDepthToViewZ( depth, this._cameraNear, this._cameraFar );
} else {
viewZNode = orthographicDepthToViewZ( depth, this._cameraNear, this._cameraFar );
}
return viewZNode;
} );
const sampleDepth = ( uv ) => {
const depth = this.depthNode.sample( uv ).r;
if ( builder.renderer.logarithmicDepthBuffer === true ) {
const viewZ = logarithmicDepthToViewZ( depth, this._cameraNear, this._cameraFar );
return viewZToPerspectiveDepth( viewZ, this._cameraNear, this._cameraFar );
}
return depth;
};
const sss = Fn( () => {
const depth = sampleDepth( uvNode ).toVar();
depth.greaterThanEqual( 1.0 ).discard();
// compute ray position and direction (in view-space)
const rayStartPosition = getViewPosition( uvNode, depth, this._cameraProjectionMatrixInverse ).toVar( 'rayStartPosition' );
const rayDirection = this._cameraViewMatrix.transformDirection( lightPosition( this._mainLight ).sub( lightTargetPosition( this._mainLight ) ) ).toConst( 'rayDirection' );
const rayEndPosition = rayStartPosition.add( rayDirection.mul( this.maxDistance ) ).toConst( 'rayEndPosition' );
// d0 and d1 are the start and maximum points of the ray in screen space
const d0 = screenCoordinate.xy.toVar();
const d1 = getScreenPosition( rayEndPosition, this._cameraProjectionMatrix ).mul( this._resolution ).toVar();
// below variables are used to control the raymarching process
// total length of the ray
const totalLen = d1.sub( d0 ).length().toVar();
// offset in x and y direction
const xLen = d1.x.sub( d0.x ).toVar();
const yLen = d1.y.sub( d0.y ).toVar();
// determine the larger delta
// The larger difference will help to determine how much to travel in the X and Y direction each iteration and
// how many iterations are needed to travel the entire ray
const totalStep = int( max( abs( xLen ), abs( yLen ) ).mul( this.quality.clamp() ) ).toConst();
// step sizes in the x and y directions
const xSpan = xLen.div( totalStep ).toVar();
const ySpan = yLen.div( totalStep ).toVar();
// compute noise based ray offset
const noise = interleavedGradientNoise( screenCoordinate );
const offset = fract( noise.add( this._temporalOffset ) ).add( rand( uvNode.add( this._frameId ) ) ).toConst( 'offset' );
const occlusion = float( 0 ).toVar();
Loop( totalStep, ( { i } ) => {
// advance on the ray by computing a new position in screen coordinates
const xy = vec2( d0.x.add( xSpan.mul( float( i ).add( offset ) ) ), d0.y.add( ySpan.mul( float( i ).add( offset ) ) ) ).toVar();
// stop processing if the new position lies outside of the screen
If( xy.x.lessThan( 0 ).or( xy.x.greaterThan( this._resolution.x ) ).or( xy.y.lessThan( 0 ) ).or( xy.y.greaterThan( this._resolution.y ) ), () => {
Break();
} );
// compute new uv, depth and viewZ for the next fragment
const uvNode = xy.div( this._resolution );
const fragmentDepth = sampleDepth( uvNode ).toConst();
const fragmentViewZ = getViewZ( fragmentDepth ).toConst( 'fragmentViewZ' );
const s = xy.sub( d0 ).length().div( totalLen ).toVar();
const rayPosition = mix( rayStartPosition, rayEndPosition, s );
const depthDelta = rayPosition.z.sub( fragmentViewZ ).negate(); // Port note: viewZ values are negative in three
// check if the camera can't "see" the ray (ray depth must be larger than the camera depth, so positive depth_delta)
If( depthDelta.greaterThan( 0 ).and( depthDelta.lessThan( this.thickness ) ), () => {
// mark as occluded
occlusion.assign( this.shadowIntensity );
Break();
} );
} );
return occlusion.oneMinus();
} );
this._material.contextNode = context( builder.getSharedContext() );
this._material.fragmentNode = sss();
this._material.needsUpdate = true;
return this._textureNode;
}
/**
* Frees internal resources. This method should be called
* when the effect is no longer required.
*/
dispose() {
super.dispose();
this._sssRenderTarget.dispose();
this._material.dispose();
}
}
export default SSSNode;
/**
* TSL function for creating a SSS effect.
*
* @tsl
* @function
* @param {TextureNode} depthNode - A texture node that represents the scene's depth.
* @param {Camera} camera - The camera the scene is rendered with.
* @param {DirectionalLight} mainLight - The main directional light of the scene.
* @returns {SSSNode}
*/
export const sss = ( depthNode, camera, mainLight ) => new SSSNode( depthNode, camera, mainLight );