File: //var/www/aspa/three/addons/nodes/materials/Line2NodeMaterial.js
import NodeMaterial, { addNodeMaterial } from './NodeMaterial.js';
import { temp } from '../core/VarNode.js';
import { varying } from '../core/VaryingNode.js';
import { property, varyingProperty } from '../core/PropertyNode.js';
import { attribute } from '../core/AttributeNode.js';
import { cameraProjectionMatrix } from '../accessors/CameraNode.js';
import { materialColor, materialLineScale, materialLineDashSize, materialLineGapSize, materialLineDashOffset, materialLineWidth } from '../accessors/MaterialNode.js';
import { modelViewMatrix } from '../accessors/ModelNode.js';
import { positionGeometry } from '../accessors/PositionNode.js';
import { mix, smoothstep } from '../math/MathNode.js';
import { tslFn, float, vec2, vec3, vec4, If } from '../shadernode/ShaderNode.js';
import { uv } from '../accessors/UVNode.js';
import { viewport } from '../display/ViewportNode.js';
import { dashSize, gapSize } from '../core/PropertyNode.js';
import { LineDashedMaterial } from 'three';
const defaultValues = new LineDashedMaterial();
class Line2NodeMaterial extends NodeMaterial {
constructor( params = {} ) {
super();
this.normals = false;
this.lights = false;
this.setDefaultValues( defaultValues );
this.useAlphaToCoverage = true;
this.useColor = params.vertexColors;
this.useDash = params.dashed;
this.useWorldUnits = false;
this.dashOffset = 0;
this.lineWidth = 1;
this.lineColorNode = null;
this.offsetNode = null;
this.dashScaleNode = null;
this.dashSizeNode = null;
this.gapSizeNode = null;
this.setupShaders();
this.setValues( params );
}
setupShaders() {
const useAlphaToCoverage = this.alphaToCoverage;
const useColor = this.useColor;
const useDash = this.dashed;
const useWorldUnits = this.worldUnits;
const trimSegment = tslFn( ( { start, end } ) => {
const a = cameraProjectionMatrix.element( 2 ).element( 2 ); // 3nd entry in 3th column
const b = cameraProjectionMatrix.element( 3 ).element( 2 ); // 3nd entry in 4th column
const nearEstimate = b.mul( - 0.5 ).div( a );
const alpha = nearEstimate.sub( start.z ).div( end.z.sub( start.z ) );
return vec4( mix( start.xyz, end.xyz, alpha ), end.w );
} );
this.vertexNode = tslFn( () => {
varyingProperty( 'vec2', 'vUv' ).assign( uv() );
const instanceStart = attribute( 'instanceStart' );
const instanceEnd = attribute( 'instanceEnd' );
// camera space
const start = property( 'vec4', 'start' );
const end = property( 'vec4', 'end' );
start.assign( modelViewMatrix.mul( vec4( instanceStart, 1.0 ) ) ); // force assignment into correct place in flow
end.assign( modelViewMatrix.mul( vec4( instanceEnd, 1.0 ) ) );
if ( useWorldUnits ) {
varyingProperty( 'vec3', 'worldStart' ).assign( start.xyz );
varyingProperty( 'vec3', 'worldEnd' ).assign( end.xyz );
}
const aspect = viewport.z.div( viewport.w );
// special case for perspective projection, and segments that terminate either in, or behind, the camera plane
// clearly the gpu firmware has a way of addressing this issue when projecting into ndc space
// but we need to perform ndc-space calculations in the shader, so we must address this issue directly
// perhaps there is a more elegant solution -- WestLangley
const perspective = cameraProjectionMatrix.element( 2 ).element( 3 ).equal( - 1.0 ); // 4th entry in the 3rd column
If( perspective, () => {
If( start.z.lessThan( 0.0 ).and( end.z.greaterThan( 0.0 ) ), () => {
end.assign( trimSegment( { start: start, end: end } ) );
} ).elseif( end.z.lessThan( 0.0 ).and( start.z.greaterThanEqual( 0.0 ) ), () => {
start.assign( trimSegment( { start: end, end: start } ) );
} );
} );
// clip space
const clipStart = cameraProjectionMatrix.mul( start );
const clipEnd = cameraProjectionMatrix.mul( end );
// ndc space
const ndcStart = clipStart.xyz.div( clipStart.w );
const ndcEnd = clipEnd.xyz.div( clipEnd.w );
// direction
const dir = ndcEnd.xy.sub( ndcStart.xy ).temp();
// account for clip-space aspect ratio
dir.x.assign( dir.x.mul( aspect ) );
dir.assign( dir.normalize() );
const clip = temp( vec4() );
if ( useWorldUnits ) {
// get the offset direction as perpendicular to the view vector
const worldDir = end.xyz.sub( start.xyz ).normalize();
const tmpFwd = mix( start.xyz, end.xyz, 0.5 ).normalize();
const worldUp = worldDir.cross( tmpFwd ).normalize();
const worldFwd = worldDir.cross( worldUp );
const worldPos = varyingProperty( 'vec4', 'worldPos' );
worldPos.assign( positionGeometry.y.lessThan( 0.5 ).cond( start, end) );
// height offset
const hw = materialLineWidth.mul( 0.5 );
worldPos.addAssign( vec4( positionGeometry.x.lessThan( 0.0 ).cond( worldUp.mul( hw ), worldUp.mul( hw ).negate() ), 0 ) );
// don't extend the line if we're rendering dashes because we
// won't be rendering the endcaps
if ( ! useDash ) {
// cap extension
worldPos.addAssign( vec4( positionGeometry.y.lessThan( 0.5 ).cond( worldDir.mul( hw ).negate(), worldDir.mul( hw ) ), 0 ) );
// add width to the box
worldPos.addAssign( vec4( worldFwd.mul( hw ), 0 ) );
// endcaps
If( positionGeometry.y.greaterThan( 1.0 ).or( positionGeometry.y.lessThan( 0.0 ) ), () => {
worldPos.subAssign( vec4( worldFwd.mul( 2.0 ).mul( hw ), 0 ) );
} );
}
// project the worldpos
clip.assign( cameraProjectionMatrix.mul( worldPos ) );
// shift the depth of the projected points so the line
// segments overlap neatly
const clipPose = temp( vec3() );
clipPose.assign( positionGeometry.y.lessThan( 0.5 ).cond( ndcStart, ndcEnd ) );
clip.z.assign( clipPose.z.mul( clip.w ) );
} else {
const offset = property( 'vec2', 'offset' );
offset.assign( vec2( dir.y, dir.x.negate() ) );
// undo aspect ratio adjustment
dir.x.assign( dir.x.div( aspect ) );
offset.x.assign( offset.x.div( aspect ) );
// sign flip
offset.assign( positionGeometry.x.lessThan( 0.0 ).cond( offset.negate(), offset ) );
// endcaps
If( positionGeometry.y.lessThan( 0.0 ), () => {
offset.assign( offset.sub( dir ) );
} ).elseif( positionGeometry.y.greaterThan( 1.0 ), () => {
offset.assign( offset.add( dir ) );
} );
// adjust for linewidth
offset.assign( offset.mul( materialLineWidth ) );
// adjust for clip-space to screen-space conversion // maybe resolution should be based on viewport ...
offset.assign( offset.div( viewport.w ) );
// select end
clip.assign( positionGeometry.y.lessThan( 0.5 ).cond( clipStart, clipEnd ) );
// back to clip space
offset.assign( offset.mul( clip.w ) );
clip.assign( clip.add( vec4( offset, 0, 0 ) ) );
}
return clip;
} )();
const closestLineToLine = tslFn( ( { p1, p2, p3, p4 } ) => {
const p13 = p1.sub( p3 );
const p43 = p4.sub( p3 );
const p21 = p2.sub( p1 );
const d1343 = p13.dot( p43 );
const d4321 = p43.dot( p21 );
const d1321 = p13.dot( p21 );
const d4343 = p43.dot( p43 );
const d2121 = p21.dot( p21 );
const denom = d2121.mul( d4343 ).sub( d4321.mul( d4321 ) );
const numer = d1343.mul( d4321 ).sub( d1321.mul( d4343 ) );
const mua = numer.div( denom ).clamp();
const mub = d1343.add( d4321.mul( mua ) ).div( d4343 ).clamp();
return vec2( mua, mub );
} );
this.fragmentNode = tslFn( () => {
const vUv = varyingProperty( 'vec2', 'vUv' );
if ( useDash ) {
const offsetNode = this.offsetNode ? float( this.offsetNodeNode ) : materialLineDashOffset;
const dashScaleNode = this.dashScaleNode ? float( this.dashScaleNode ) : materialLineScale;
const dashSizeNode = this.dashSizeNode ? float( this.dashSizeNode ) : materialLineDashSize;
const gapSizeNode = this.dashSizeNode ? float( this.dashGapNode ) : materialLineGapSize;
dashSize.assign( dashSizeNode );
gapSize.assign( gapSizeNode );
const instanceDistanceStart = attribute( 'instanceDistanceStart' );
const instanceDistanceEnd = attribute( 'instanceDistanceEnd' );
const lineDistance = positionGeometry.y.lessThan( 0.5 ).cond( dashScaleNode.mul( instanceDistanceStart ), materialLineScale.mul( instanceDistanceEnd ) );
const vLineDistance = varying( lineDistance.add( materialLineDashOffset ) );
const vLineDistanceOffset = offsetNode ? vLineDistance.add( offsetNode ) : vLineDistance;
vUv.y.lessThan( - 1.0 ).or( vUv.y.greaterThan( 1.0 ) ).discard(); // discard endcaps
vLineDistanceOffset.mod( dashSize.add( gapSize ) ).greaterThan( dashSize ).discard(); // todo - FIX
}
// force assignment into correct place in flow
const alpha = property( 'float', 'alpha' );
alpha.assign( 1 );
if ( useWorldUnits ) {
const worldStart = varyingProperty( 'vec3', 'worldStart' );
const worldEnd = varyingProperty( 'vec3', 'worldEnd' );
// Find the closest points on the view ray and the line segment
const rayEnd = varyingProperty( 'vec4', 'worldPos' ).xyz.normalize().mul( 1e5 );
const lineDir = worldEnd.sub( worldStart );
const params = closestLineToLine( { p1: worldStart, p2: worldEnd, p3: vec3( 0.0, 0.0, 0.0 ), p4: rayEnd } );
const p1 = worldStart.add( lineDir.mul( params.x ) );
const p2 = rayEnd.mul( params.y );
const delta = p1.sub( p2 );
const len = delta.length();
const norm = len.div( materialLineWidth );
if ( ! useDash ) {
if ( useAlphaToCoverage ) {
const dnorm = norm.fwidth();
alpha.assign( smoothstep( dnorm.negate().add( 0.5 ), dnorm.add( 0.5 ), norm ).oneMinus() );
} else {
norm.greaterThan( 0.5 ).discard();
}
}
} else {
// round endcaps
if ( useAlphaToCoverage ) {
const a = vUv.x;
const b = vUv.y.greaterThan( 0.0 ).cond( vUv.y.sub( 1.0 ), vUv.y.add( 1.0 ) );
const len2 = a.mul( a ).add( b.mul( b ) );
// force assignment out of following 'if' statement - to avoid uniform control flow errors
const dlen = property( 'float', 'dlen' );
dlen.assign( len2.fwidth() );
If( vUv.y.abs().greaterThan( 1.0 ), () => {
alpha.assign( smoothstep( dlen.oneMinus(), dlen.add( 1 ), len2 ).oneMinus() );
} );
} else {
If( vUv.y.abs().greaterThan( 1.0 ), () => {
const a = vUv.x;
const b = vUv.y.greaterThan( 0.0 ).cond( vUv.y.sub( 1.0 ), vUv.y.add( 1.0 ) );
const len2 = a.mul( a ).add( b.mul( b ) );
len2.greaterThan( 1.0 ).discard();
} );
}
}
let lineColorNode;
if ( this.lineColorNode ) {
lineColorNode = this.lineColorNode;
} else {
if ( useColor ) {
const instanceColorStart = attribute( 'instanceColorStart' );
const instanceColorEnd = attribute( 'instanceColorEnd' );
const instanceColor = positionGeometry.y.lessThan( 0.5 ).cond( instanceColorStart, instanceColorEnd );
lineColorNode = instanceColor.mul( materialColor );
} else {
lineColorNode = materialColor;
}
}
return vec4( lineColorNode, alpha );
} )();
this.needsUpdate = true;
}
get worldUnits() {
return this.useWorldUnits;
}
set worldUnits( value ) {
if ( this.useWorldUnits !== value ) {
this.useWorldUnits = value;
this.setupShaders();
}
}
get dashed() {
return this.useDash;
}
set dashed( value ) {
if ( this.useDash !== value ) {
this.useDash = value;
this.setupShaders();
}
}
get alphaToCoverage() {
return this.useAlphaToCoverage;
}
set alphaToCoverage( value ) {
if ( this.useAlphaToCoverage !== value ) {
this.useAlphaToCoverage = value;
this.setupShaders();
}
}
}
export default Line2NodeMaterial;
addNodeMaterial( 'Line2NodeMaterial', Line2NodeMaterial );