我想找到相交曲线和直线的点。创建了raycast,但效果不佳。射线的点远离实际的交点。
Webgl 1,threejs 0.109
var sartPoint = new THREE.Vector3( -30, -50, 0 );
var endPoint = new THREE.Vector3( 50, 80, 0 );
var geometry = new THREE.Geometry();
geometry.vertices.push(sartPoint);
geometry.vertices.push(endPoint);
var materialTmp = new THREE.LineBasicMaterial( { color: 0xffffff, linewidth: 5 } );
var itemTmp = new THREE.Line( geometry, materialTmp );
_this.add( itemTmp, 'lines' );
scene.updateMatrixWorld()
var curve = new THREE.EllipseCurve(
0, 0, // ax, aY
10, 10, // xRadius, yRadius
0, 2 * Math.PI, // aStartAngle, aEndAngle
false, // aClockwise
0 // aRotation
);
var points = curve.getPoints( 10 );
var geometry = new THREE.BufferGeometry().setFromPoints( points );
var material = new THREE.LineBasicMaterial( { color : 0xff00ff } );
var ellipse = new THREE.Line( geometry, material );
scene.add( ellipse );
var raycaster = new THREE.Raycaster(sartPoint, endPoint.clone().normalize());
var intersects = raycaster.intersectObject( ellipse );
console.log(intersects);
if(intersects.length > 0){
// FIRST dot of intersect
var dotGeometry2 = new THREE.Geometry();
dotGeometry2.vertices.push(intersects[0].point);
var dotMaterial2 = new THREE.PointsMaterial( { size: 5, color: 0x00ff00 } );
var dot2 = new THREE.Points( dotGeometry2, dotMaterial2 );
_this.add( dot2, 'points' );
}
Raycaster
构造函数的第二个参数是方向向量。代替:
endPoint.clone().normalize()
我认为您想要:
endPoint.clone().sub(startPoint).normalize()