Get it working

examples/jsm/lines/LineSegments2.js

@@ -1,17 +1,12 @@
+import { Matrix4, Vector3, Vector4, Line3, Math as MathUtils, Mesh, InstancedInterleavedBuffer, InterleavedBufferAttribute  } from "../../../build/three.module.js";
+import { LineSegmentsGeometry } from "../lines/LineSegmentsGeometry.js";
+import { LineMaterial } from "../lines/LineMaterial.js";
+
 /**
  * @author WestLangley / http://github.com/WestLangley
  *
  */
 
-import {
-	InstancedInterleavedBuffer,
-	InterleavedBufferAttribute,
-	Mesh,
-	Vector3
-} from "../../../build/three.module.js";
-import { LineSegmentsGeometry } from "../lines/LineSegmentsGeometry.js";
-import { LineMaterial } from "../lines/LineMaterial.js";
-
 var LineSegments2 = function ( geometry, material ) {
 
 	Mesh.call( this );
@@ -61,7 +56,153 @@ LineSegments2.prototype = Object.assign( Object.create( Mesh.prototype ), {
 
 		};
 
-	}() )
+	}() ),
+
+	raycast: ( function () {
+
+		var start = new Vector4();
+		var end = new Vector4();
+
+		var ssOrigin = new Vector4();
+		var ssOrigin3 = new Vector3();
+		var mvMatrix = new Matrix4();
+		var line = new Line3();
+		var closestPoint = new Vector3();
+
+		return function raycast( raycaster, intersects ) {
+
+			if ( raycaster.camera === null ) {
+
+				console.error( 'LineSegments2: "Raycaster.camera" needs to be set in order to raycast against sprites.' );
+
+			}
+
+			var ray = raycaster.ray;
+			var camera = raycaster.camera;
+			var projectionMatrix = camera.projectionMatrix;
+
+			var geometry = this.geometry;
+			var material = this.material;
+			var resolution = material.resolution;
+			var lineWidth = material.linewidth;
+
+			var instanceStart = geometry.attributes.instanceStart;
+			var instanceEnd = geometry.attributes.instanceEnd;
+
+			// ndc space [ - 0.5, 0.5 ]
+			ray.at( 1, ssOrigin );
+			ssOrigin.w = 1;
+			ssOrigin.applyMatrix4( camera.matrixWorldInverse );
+			ssOrigin.applyMatrix4( projectionMatrix );
+			ssOrigin.multiplyScalar( 1 / ssOrigin.w );
+
+			// screen space
+			ssOrigin.x *= resolution.x / 2;
+			ssOrigin.y *= resolution.y / 2;
+			ssOrigin.z = 0;
+
+			ssOrigin3.copy( ssOrigin );
+
+			var matrixWorld = this.matrixWorld;
+			mvMatrix.multiplyMatrices( camera.matrixWorldInverse, matrixWorld );
+
+			for ( var i = 0, l = instanceStart.count; i < l; i ++ ) {
+
+				// TODO: Maybe have to clip the line based on the camera?
+
+				start.fromBufferAttribute( instanceStart, i );
+				end.fromBufferAttribute( instanceEnd, i );
+
+				start.w = 1;
+				end.w = 1;
+
+				// camera space
+				start.applyMatrix4( mvMatrix );
+				end.applyMatrix4( mvMatrix );
+
+				// clip space
+				start.applyMatrix4( projectionMatrix );
+				end.applyMatrix4( projectionMatrix );
+
+				// console.log( start.z, end.z )
+				// // segment is behind camera near
+				// if ( start.z > 0 && end.z > 0 ) {
+
+				// 	continue;
+
+				// }
+				// console.log(2 );
+
+				// // segment is in front of camera far
+				// if ( start.z < - 1 && end.z < - 1 ) {
+
+				// 	continue;
+
+				// }
+
+				// ndc space [ - 0.5, 0.5 ]
+				start.multiplyScalar( 1 / start.w );
+				end.multiplyScalar( 1 / end.w );
+
+				// screen space
+				start.x *= resolution.x / 2;
+				start.y *= resolution.y / 2;
+
+				end.x *= resolution.x / 2;
+				end.y *= resolution.y / 2;
+
+				// create 2d segment
+				line.start.copy( start );
+				line.start.z = 0;
+
+				line.end.copy( end );
+				line.end.z = 0;
+
+				// get closest point on ray to segment
+				var param = line.closestPointToPointParameter( ssOrigin, true );
+				line.at( param, closestPoint );
+
+				// check if the intersection point is within clip space
+				var zPos = MathUtils.lerp( start.z, end.z, param );
+				var isInClipSpace = true; //zPos < 0 && zPos > - 1;
+
+				console.log(ssOrigin3 ); //ssOrigin3.distanceTo( closestPoint ), lineWidth)
+
+				if ( isInClipSpace && ssOrigin3.distanceTo( closestPoint ) < lineWidth * 0.5 ) {
+
+					line.start.fromBufferAttribute( instanceStart, i );
+					line.end.fromBufferAttribute( instanceEnd, i );
+
+					line.start.applyMatrix4( matrixWorld );
+					line.end.applyMatrix4( matrixWorld );
+
+					var pointOnLine = new Vector3();
+					line.at( param, pointOnLine );
+
+					var point = new Vector3();
+					ray.closestPointToPoint( pointOnLine, point );
+
+					intersects.push( {
+
+						point: point,
+						pointOnLine: pointOnLine,
+						distance: ray.origin.distanceTo( point ),
+
+						object: this,
+						face: null,
+						faceIndex: i,
+						uv: null,
+						uv2: null,
+
+					} );
+
+				}
+
+			}
+
+		}
+
+	} () )
 
 } );