I have a THREE.JS scene where there's a plane geometry in the middle of the scene. The plane geometry has a camera added to it. I also am using this example http://mrdoob.github.io/three.js/examples/webgl_materials_lightmap.html to add a lightmap and am adding it to my plane geometry.
Psuedocode:
planeGeometry.add(camera);
planeGeometry.add(sphereGeometryLightMap);
The problem is that when I try to rotate the sphere geometry on any axis, nothing happens. I tried using .rotation and setting the matrix4. Why is it that I can't rotate this sphere object when added to another object? How can I work around this?
You don't need to add the camera to the planeGeometry.
Also I assume that sphereGeometryLightMap is of type THREE.Mesh in which case you need to add it to the scene. Not to the planeGeometry.
If you want the sphereGeometry relative to the planeGeometry you can do:
var object = new THREE.Object3D();
object.add (planeGeometry);
object.add (sphereGeometry);
Before you add the geometries to the object you position them relative as you want.
Then, instead of modifying the planeGeometry, you modify the object.
Related
I want to realize a 3D interactive globe with three.js and I wonder if there is a way to intersect over Sprites primitive with the Raycaster?
If you check the source code for RayCaster at
https://github.com/mrdoob/three.js/blob/master/src/core/Raycaster.js
it would appear that the intersectObject function only checks objects that are instances of THREE.Particle or THREE.Mesh, not THREE.Sprite. Possibly this is because sprites could be set to use screen coordinates, and so a ray that projects into your 3d scene wouldn't make sense in this situation, or if placed in the scene as the sprite image always faces the camera, it doesn't act like your standard 3d mesh.
Perhaps you could attach a PlaneGeometry or a very thin CubeGeometry to the position of your sprite, set its rotation to the rotation of the camera so that it is always parallel to the view plane of the camera like the sprite is, and then check for intersections with the mesh instead?
I want to place a circle on an object when you click on it.
I updated this example to work with webGL renderer (I basically changed THREE.SpriteCanvasMaterialto THREE.SpriteMaterial), but not only is the circle now a square, it also glitches with the surface of the object. Here's a JSFiddle that demonstrates my problem (click an object to test).
I found some similar questions on stackoverflow, but I can't seem to make it work in my example. Any tips?
you are adding sprites into a moving 3d scene, easy way to do what you want is to add spheres
var particle = new THREE.Mesh(new THREE.SphereGeometry(10,10,10),
new THREE.MeshBasicMaterial({color:0xff0000}) );
particle.position.copy( intersects[ 0 ].point );
scene.add( particle );
if you want real flat circles you will have to create a circular geometry and align it correctly to the object so it sits atop of the rectangle wall and if you want circles that do not deform when object is turned you will need some custom shader stuff
I'm using BufferGeometry to draw triangles.
I can use a mesh geometry, specifiyng 3 index-attribute for every triangle. I'm using a basic material without wireframe. I suposse I'll can use raycast.
Also I have seen the linesegments approach for wireframe. Interesting.
Ok, my problem... I'd like to see my triangles as a wireframe and also I need raycast. So .... the solution is to create my own shader, isn't it ?
Thanks
you dont have to create a custom shader you can have a mesh with wireframe material, and the ray should still "hit" the object
var mesh = new THREE.Mesh(geometry,new THREE.MeshBasicMaterial({wireframe : true}));
if it for some reason does not hit or you want to LineSegments object you can keep track of all transformations that affected the object, and apply them onto a mesh you wont add to scene
var segmentObject = new THREE.LineSegments(geometry,lineMaterial);
scene.add(segmentObject);
var meshNotInScene = new THREE.Mesh(geometry,dummyMaterial);
and you will use the mesh object to determine if raycast hit the object
this way you can have a different hitbox for an object for example if you have a flying donut by pairing it with a circle mesh you can select it even if you click in its hole etc...
keep in mind that materials have sides and if you dont care about which side is which set "side" to THREE.DoubleSide
I want to move and rotate the camera but keep a PointLight on the same position relative to the camera. I've read a bunch of threads saying that you can add the light object to the camera instead of the scene. Like so:
pointLight = new THREE.PointLight( 0xffffff );
pointLight.position.set(1,1,2);
camera.add(pointLight);
However this does not seem to work for me. Instead I now when the camera changes set the light's position by applying the cameras matrixWorld to my desired relative light position. This works, but adding the light to the camera seems like a cleaner solution.
I'm a doing something wrong or is adding light object to the camera deprecated?
Thanks!
You need to add the camera to the scene if the camera has a child object, such as a `PointLight'.
scene.add( camera );
three.js r.68
I want to realize a 3D interactive globe with three.js and I wonder if there is a way to intersect over Sprites primitive with the Raycaster?
If you check the source code for RayCaster at
https://github.com/mrdoob/three.js/blob/master/src/core/Raycaster.js
it would appear that the intersectObject function only checks objects that are instances of THREE.Particle or THREE.Mesh, not THREE.Sprite. Possibly this is because sprites could be set to use screen coordinates, and so a ray that projects into your 3d scene wouldn't make sense in this situation, or if placed in the scene as the sprite image always faces the camera, it doesn't act like your standard 3d mesh.
Perhaps you could attach a PlaneGeometry or a very thin CubeGeometry to the position of your sprite, set its rotation to the rotation of the camera so that it is always parallel to the view plane of the camera like the sprite is, and then check for intersections with the mesh instead?