How to detect intersections of two faces of two bufferGeometryBox?

Questions
21

Because there are 12 faces, and i want to detect side

22

So, we have 12 faces on 6 sides, each side has 2 faces, thus to find the side by a face index, you need to divide it by 2.
Math.floor( intersects[0].faceIndex / 2 );

23

Oh, sorry. This number from other code. Yes, ofcourse, but my face has faceIndex in range from 30 to 1800

24

You can see it in console log
http://alovert.ru/

25

Are you sure that you intersect a box with 12 faces?

26

Not sure. I set group in raycaster

intersects = raycaster.intersectObject(group, true);

27

If i set single mesh object, intersection not working

28

Pardon, i forgot delete this code .toNonIndexed()

29

Hi again! I have some trouble ā€¦

How to intersect non indexed buffer geometry? I want to detect intersection between two defferent faces of two different non indexed buffergeometry. I set ray from middle of each faces, but raycaster don`t work with non indexed geometry.

I want to see result like this:enter image description here

Thank you very much!

my code

var box = new THREE.Mesh(geometry.toNonIndexed(), material);

var raycaster = new THREE.Raycaster();
var intersects = [];

var pos = box.geometry.attributes.position;
var ori = new THREE.Vector3();
var dir = new THREE.Vector3();

var a = new THREE.Vector3(),
  b = new THREE.Vector3(),
  c = new THREE.Vector3(),
  tri = new THREE.Triangle();



var faces = pos.count / 3;
for (let i = 0; i < faces; i++) {
  a.fromBufferAttribute(pos, i * 3 + 0);
  b.fromBufferAttribute(pos, i * 3 + 1);
  c.fromBufferAttribute(pos, i * 3 + 2);
  tri.set(a, b, c);
  tri.getMidpoint(ori);
  tri.getNormal(dir)
  // scene.add(new THREE.ArrowHelper(raycaster.ray.direction, 
  raycaster.ray.origin, 30, 0xff0000));
  raycaster.set(ori, dir);
  intersects = raycaster.intersectObject(box, true);

  if (intersects.length > 0) {

    console.log(intersects[0]);

  }
}
30

/cc

31

What does it mean?

32

Nothing bad. Just the other users can track the issue on other resources.

33

Oh, ok! I just intersting what mean /cc :smile:

34

CC comes from the email domain: https://www.techwalla.com/articles/what-does-cc-mean-in-a-text

35

Wow, this is a discovery for me. Iā€™m Russian :grinning:

37

Hi! I sucessfully set ray from each faces and when intersection detect face , its return flag true. But i have a problem. I cant to return flag false when i delete object, that intersects. My code:

				box.userData.sides = {
					0: false,
					1: false,
					2: false,
					3: false,
					4: false,
					5: false
				}
				

				collision.push(box);
				scene.add(box);

				checkRaycast();
			
		
	}


	load(0, 0, 0, 'cube', 0, 0, 0);

	function checkRaycast() {
		var raycaster = new THREE.Raycaster();
		var intersects = [];
		for (let j = 0; j < collision.length; j++) {

			var pos = collision[j].geometry.attributes.position; 
			var ori = new THREE.Vector3();
			var dir = new THREE.Vector3();
			var a = new THREE.Vector3(),
				b = new THREE.Vector3(),
				c = new THREE.Vector3(),
				tri = new THREE.Triangle();
		
			var index = collision[j].geometry.index;	
			var faces = index.count / 3;
			scene.updateMatrixWorld()
			for (let i = 0; i < faces; i++) {
				a.fromBufferAttribute(pos, index.array[i * 3 + 0]);
				b.fromBufferAttribute(pos, index.array[i * 3 + 1]);
				c.fromBufferAttribute(pos, index.array[i * 3 + 2]);
				a.set(a.x + collision[j].position.x, a.y + collision[j].position.y, a.z + collision[j].position.z);
				b.set(b.x + collision[j].position.x, b.y + collision[j].position.y, b.z + collision[j].position.z);
				c.set(c.x + collision[j].position.x, c.y + collision[j].position.y, c.z + collision[j].position.z);
				tri.set(a, b, c);
				tri.getMidpoint(ori);
				tri.getNormal(dir);
				
				raycaster.set(ori, dir);	
				
				intersects = raycaster.intersectObjects(collision, true);
				
				//scene.add(new THREE.ArrowHelper(dir, ori, 500, 0xff0000));
				if (intersects.length > 0) {
					var intFace = Math.floor(intersects[0].faceIndex / 2);
					if (intersects[0].distance > 0 && intersects[0].distance < 0.2) {
						intersects[0].object.userData.sides[intFace] = true;
					}
				} else {
			
					collision[j].userData.sides[0] = false;
					collision[j].userData.sides[1] = false;
					collision[j].userData.sides[2] = false;
					collision[j].userData.sides[3] = false;
					collision[j].userData.sides[4] = false;
					collision[j].userData.sides[5] = false;
					
				}

			}
		}
	}

My project: https://alovert.ru

To add object, please click on object LBM, to delete RBM

38

I set the flag to false for each side, if the sides do not intersect. But this flag is set for all sides, regardless of whether the sides intersect or not