I am trying to do a face explode effect as seen in this example: http://threejs.org/examples/#webgl_modifier_tessellation
However the example uses THREE.TextGeometry and I am using an imported model using
THREE.JSONLoader();
loader.load( "models/animated/Brain-New_2154_ft.js", function ( geometry ) {
var material = new THREE.MeshLambertMaterial( {
color: 0x6249a3,
vertexColors: THREE.FaceColors,
morphTargets: true,
overdraw: 0.5
} );
How can I use an imported model for this effect? Do I have to convert the model to something before it's faces, vertices can be affected with the explodeModifier and TessellateModifier libraries? thanks!
You need to use the THREE.ExplodeModifier() which is not included in the core, you have to explicitly import it in (see line 140 in your example).
The ExplodeModifier just loops through the vertices array in your geometry so it should work with any model type that can be successfully imported.
var geometry = new THREE.PlaneGeometry(10,10,10,10);
var explodeModifier = new THREE.ExplodeModifier();
explodeModifier.modify( geometry );
This gives you an array of faces you can manipulate the same way you do the vertices
Related
I am loading a GLTF model into threejs. All the materials used on the object (and there a quite a few of them), use a mesh basic material, and we want them to be a material that can be affected by lights. Is there a way to convert all materials from a basic material to one that can receive lights, like Phong (including their existing properties?).
I can currently add a new material as follows:
glb.scene.traverse(child => {
if (child.isMesh) {
//child.material = new THREE.MeshPhongMaterial({ flatShading: true });
}
});
but everything just looks a solid gray color and doesn't contain any of the properties of the mesh basic material it replaced.
The default material in glTF is usually mapped to MeshStandardMaterial in three.js — your model must have the "unlit" glTF extension (KHR_materials_unlit) enabled if it's creating MeshBasicMaterial. Short of changing that in a modeling tool like Blender, which might be easiest, you can also convert it in three.js...
model.traverse((child) => {
if ( ! child.isMesh ) return;
var prevMaterial = child.material;
child.material = new MeshPhongMaterial();
MeshBasicMaterial.prototype.copy.call( child.material, prevMaterial );
});
Note that the reverse does not necessarily work — calling a complex material's copy() method on a simpler material (like MeshBasicMaterial) will cause it to look for properties that do not exist.
I am loading a very complex 3D model from a PLY file (over 60Mb). In my project I need to use the orbit-control to move around the object. Obviously due to the large file the operation is painfully slow in some couputers. In order to speed up things a bit I am trying to convert my geometry into a Buffer geometry with the following lines of code:
this.loader.load('assets/data/GuyFawkesMask.ply', function (geometry) {
var bufferGeometry = new THREE.BufferGeometry().fromGeometry( geometry );
console.log(bufferGeometry);
// Create object
let object =
new THREE.Mesh(bufferGeometry,
new THREE.MeshPhongMaterial(
{
color: 0xFFFFFF,
//vertexColors: THREE.VertexColors,
shading: THREE.FlatShading,
shininess: 0
})
);
_this.add(object);
});
But I am getting the following error:
TypeError: Cannot read property '0' of undefined
at DirectGeometry.fromGeometry (three.module.js:12219)
at BufferGeometry.fromGeometry (three.module.js:14307)
at threed-viewer.component.ts:379
at index.js:52
at XMLHttpRequest. (three.module.js:29263)
at ZoneDelegate.webpackJsonp.818.ZoneDelegate.invokeTask (zone.js:367)
at Object.onInvokeTask (ng_zone.js:264)
at ZoneDelegate.webpackJsonp.818.ZoneDelegate.invokeTask (zone.js:366)
at Zone.webpackJsonp.818.Zone.runTask (zone.js:166)
at XMLHttpRequest.ZoneTask.invoke (zone.js:420)
Any idea?
Thank you,
Dino
Just posting prisoner849 comment (as an answer) for future reference:
If I get it right, looking into the source code of PLYLoader.js, the
geometry, which the callback function returns, is already of
THREE.BufferGeometry()
I'm experimenting with one of the examples, namely the webgl_loader_obj.html to load an .obj file exported from blender into three.js
This works and displays the model exactly as expected.
Now i was looking at the use of material.shading = THREE.SmoothShading.
For this to work, the model needs to have vertex normals.
the exported file from blender has no normals defined.
So i looked at using computeVertexNormals to calculate the required normals.
however this doesn't appear to be doing anything, the resulting view is of the unsmoothed model.
further to this, as a test, i exported the same model, with normals.
loading it straight in, it appeared smoothed.
If i then did computeFaceNormals() & computeVertexNormals() it would result in the unsmoothed mesh again.
var loader = new THREE.OBJLoader( manager );
loader.load( 'test.obj', function ( object ) {
object.traverse( function ( child ) {
if ( child instanceof THREE.Mesh ) {
child.material = new THREE.MeshLambertMaterial( { color: 0xff6600 });
child.geometry.computeFaceNormals();
child.geometry.computeVertexNormals();
child.material.shading = THREE.SmoothShading;
}
} );
Geometry.computeVertexNormals() "smooths" the vertex-normals by computing each vertex-normal to be the average of the face-normals of all faces that share that vertex.
If each face of your geometry has unique vertices (i.e., no vertices are shared with a neighboring face), then computeVertexNormals() will result in each face's vertex-normals being the same as the face-normal, and the mesh shading will appear faceted.
three.js r.71
Part of a project that I'm working on requires that I pull in an array of base64 images, then pull in imported models via THREE.JSONLoader(). If I keep these two types of assets apart, they both load without issue. However, if I try to apply the image as a material to the model, I get an error.
WARNING: Output of vertex shader 'vWorldPosition' not read by fragment shader
I realize that much of the time when you load in geometry, you need to run geometry.computeTangets(), but that isn't working. I thought perhaps there's another computation that might need to run prior to creating a mesh with the geometry and the material. Here's what I have:
var material = new THREE.MeshPhongMaterial({
map: THREE.ImageUtils.loadTexture(data.images[0]),
shininess: 4.0,
});
var loader = new THREE.JSONLoader();
loader.load("app/museum/geometry.json", function (geometry) {
geometry.computeTangents();
mesh = new THREE.Mesh(geometry, material);
mesh.scale.set(100, 100, 100);
mesh.position.y = 150;
mesh.position.x = 0;
scene.add(mesh);
});
I assume there's an additional setting or method that needs to be called, or perhaps there are attributes in the geometry.json that I need to set manually?
I have a quite complex shape (dressed girl) that in Blender is broken down into different objects and it's loaded into Three.js with the JSON loader (with a little hack I made, that uses zipped files instead of just JSON files, as there are a lot of vertices).
As I want to change dynamically the style of the dress from a Web page, I was wondering how I can show/hide different pieces (e.g. sleeves) in the scene.
I tried traversing the THREE.Mesh, but there are no children.
When I export from Blender with the JSON exporter, I don't see anything referring to the names of the objects in the JSON. Is the structure lost?
If you are using meshes containing lots of vertices, I would advise you to use the openCTM webGL loader instead of zip hacking. Here is a link to the loader : http://threejs.org/examples/webgl_loader_ctm.html
This mesh compression tool uses LZMA compression method and can reduce the size of your files by 93%...
Concerning the JSONLoader, using an array might help:
var meshes = [];
...
var loader = new THREE.JSONLoader();
var onGeometry = function(geom)
{
var mesh = new THREE.SceneUtils.createMultiMaterialObject(geom, [material]);
meshes.push( mesh );
...
scene.add(mesh);
};
loader.load("yourfile.js", onGeometry);
Hope this helps
It is possible to load an entire scene with several meshes from a json file exported from Blender and handle them separately!
You can follow the complete process of exporting a entire scene from Blender and the right way of handling the exported meshes on my answer of this post.
So, you can get the different meshes and manipulate them separately using the getObjectByName method. But it is important to know that the loaded object isn't a Geometry anymore. It is labeled with the Scene type by now and it must be handled in a different way.
The loading code must look like this one:
loader = new THREE.JSONLoader();
loader.load( "obj/Books.json", function ( loadedObj ) {
var surface = loadedObj.getObjectByName("Surface");
var outline = loadedObj.getObjectByName("Outline");
var mask = loadedObj.getObjectByName("Mask");
scene.add(surface);
scene.add(outline);
scene.add(mask);
} );
Besides, you can handle the multiple materials of single mesh using THREE.MeshFaceMaterial like in the following code:
var mat1 = new THREE.MeshLambertMaterial( { map: texture1 } );
var mat2 = new THREE.MeshLambertMaterial( { map: texture2 } );
var materials = [mat1, mat2];
var faceMat = new THREE.MeshFaceMaterial(materials);
mesh = new THREE.Mesh( geometry, faceMat );
scene.add( mesh );
Hope this helps :)