How to move (either move or drag n drop) three js objects(for ex. A Cube) from one div to another.
I am making divs by putting all the three js left hand side objects in one div(with one scene and perspective camera) and a different right div(with different div and camera).
[everything else other then the camera and scene is generic]
The problem i am facing is, Raycaster takes camera as input, now if i pass the left hand side camera in raycaster, only left hand side objects intersection is returned, if i pass right hand div camera, only right hand side object's intersection is returned, everything else is returned as 0,0,0.
Any other idea is most welcome.
Related
I am trying to achieve movement of an object on walls, instead of only one plane. In this example, an object dragged on walls by using:
intersects = raycaster.intersectObjects([walls]);
object.position.copy(intersects[0].point);
However, with this method, the object jumps because the object's center moves to the mouse. There is a related question and helpful JSFiddle for dragging on one plane without jumpin Would you please help me to modify it for multiples planes (walls)? Thanks
After reading your comment, I think what you're looking for is you want the object to animate to the position. You can do this a few ways. The "threejs" way is to move it each frame (within the animate/update loop). You could do this with Vector3.lerp by storing intersects[0].point as your target location and lerping your object.position to it each frame. Another option is to use an animation library like animejs or gsap.
I need to get the camera up direction and i've tried many ways with no luck, i'm not an expert of quaternions so i'm doubting i did it right.
I've tried:
camera.up
camera.up.applyMatrix4(camera.matrixWorld);
new THREE.Vertex3(0,1,0).applyMatrix4(camera.matrixWorld);
camera.up.normalize().applyMatrix4(camera.matrixWorld);
after this i create two planes passing by two points of my interest, and add the plane helper to the scene and i can see they are very far from where i was expecting them. (i'm expecting two planes that looks like the top and bottom of the camera frustum).
P.s. the camera is a shadow camera of a directional light so an orthographic camera, and i manipulate the directional light position and target before doing this operation, but i've called updateMatrixWorld on the light, on it's target and the camera, on the camera i've called also updateProjectionMatrix... still no results
I've made a sandbox to see what i've tried till now, and better visualize what i want to achieve:
https://codesandbox.io/embed/throbbing-cache-j5yse
once i manage to get the green arrow to point to the top of the blue triangle of the camera helper i'm good to go
In the normal render flow, shadow camera matrices are updated as part of rendering the shadow map (WebGLShadowMap.render).
However, if you want the updated matrix values before the render, then you'll need to update them manually (you already understand this part).
The shadow camera is a property of (not a child of) the DirectionalLight. As such, it doesn't follow the same rules as other scene objects when it comes to updating its matrices (because it's not really a child of the scene). Instead, you need to call the shadow property's updateMatrices method (inherited from LightShadow.updateMatrices).
const dl = new THREE.DirectionalLight(0xffffff, 1)
dl.shadow.updateMatrices(dl) // <<------------------------ Updates the shadow camera
This updates the shadow camera with information from the DirectionalLight's own matrix, and its target's matrix, to properly orient the shadow camera.
Finally, it looks like you're trying to get the "world up" of the camera. Personally, I'd use the convenience function localToWorld:
let up = new THREE.Vector3(0, 1, 0)
dl.shadow.camera.localToWorld(up) // destructively converts "up" from local-to-camera into world coordinates
via trial and errors i've figured out that what gave me the correct result was:
calling
directionalLight.shadow.updateMatrices(...)
and then
new THREE.Vector3(0,1,0).applyQuaternion(directionalLight.shadow.camera.quaternion)
I have two SpotLights in my canvas. One is front side and the other is left side. I know how to set them but I want to know how I can get the exact position. Maybe using console.log?
itsLight.position.set(?,?,?);
The light's position is in the position attribute:
console.log(itsLight.position.x, itsLight.position.y, itsLight.position.z);
The coordinates for front side and left side depend on where you have your camera. It also depends on what kind of light it is. DirectionalLight and PointLight behave differently.
Does anyone know how can I perform a simple collision check to push back camera so that it doesn't "go through" scene? Is it possible to make a camera respect the 3D objects "masses"? I'm trying to make a small simulator to fly around a building, and enter some rooms, but the camera will always go inside objects.
You can set 3 raycasters for each 3D directions. You append them and the camera to an empty object that you move (not the camera) so everything moves at once.
When your raycasters intersects something you make the difference between the intersection point coordinates and the empty object position. This gives you all the information you can need.
If you want to define objects parameters like masses, add them to object.userData and access them via the returned intersection array.
So I'd like to create some lines that can be modified from points that are connecting them.
An example of initial state
First one has been moved down, second one up and third one right and down.
On the implementation side I currently have two meshes. First one is stretched out so that it would cover the distance from its starting point to the next point and second one marks the starting point.
var meshLine = new THREE.Mesh(boxGeometry, material);
meshLine.position.set(x,y,z);
meshLine.scale(1,1,distancetonextpoint);
var meshPoint = new THREE.Mesh(sphereGeometry, material);
meshPoint.position.set(x,y,z);
meshPoint.scale(2,2,2);
What I want from it is that when the user drags the circular point other lines would stretch or change their position accordingly to the one being dragged.
Is there some more reasonable solution for this as I feel mine is not quite good and clean. I'd have to do quite heavy lifting to get the movement done.
I've also looked at this example which looks visually very nice but could not integrate it to my system.
You mean you need to edit the object's geometry by dragging their vertices (here a line).
Objects'vertices can't be dragged theirselves, so you need to loop through the geometry and create little spheres at each vertex position ;
You set a raycaster to pick those spheres, as in the examples ;
Your screen is 2D so to drag objects in 3D you need a surface perpendicular to the screen, that intersects the sphere position. For this you set an invisible plane at the vertex position and make it look at the camera ;
Once you can correctly drag the spheres, you tell the corresponding vertices on the object (your lines) they must keep the same position as their spheres ;
End with geometry.verticesNeedUpdate=true.
And you have your new geometry
For code details on picking objects look at the official picking objects'example draggable cubes
This example shows how to use it for editing objects
Comment if you need more explanations