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Three.js Multiple Materials in Plane Geometry

I am trying to use a single plane to show multiple materials. I am currently using the MultiMaterial with the materials I plan to use inside of (textured).
The issue I am having is that the materials I use seem to get split across the entire plane into little chunks for each face. However I would like to have a material cover a 1 / n amount of the plane/mesh.
My current code (shortened):
var splitX = 2;
var splitY = 2;
var geometry = new THREE.PlaneGeometry(800, 800, splitX, splitY);
var materials = [
new THREE.MeshBasicMaterial({
map: preloaded texture..., side: THREE.DoubleSide
}),
new THREE.MeshBasicMaterial({
color: 0xff0000, side: THREE.DoubleSide
})
];
// set a single square inside the plane to the desired textured material
geometry.faces[0].materialIndex = 0;
geometry.faces[1].materialIndex = 0;
// set the other squares inside the plane to use the coloured material
for(var i = 1; i < geometry.faces.length / 2; i++) {
geometry.faces[i * 2].materialIndex = 1;
geometry.faces[i * 2 + 1].materialIndex = 1;
}
var mesh = new THREE.Mesh(geometry, new THREE.MultiMaterial(materials));
scene.add(mesh);
The output: http://prnt.sc/e8un2a
I marked each corner of the texture to see whether it would show the entire texture in the 2 faces I specified and it did not. Any help would be appreciated to resolve this! :)

THREE.js translation/position weirdness

I'm trying to generate random planes that would be in random position in the screen and of random size. The problem I have is that I really don't understand the set.position values. What are they representing? I tried to search every where for an answer but couldn't find.
Here's my code for the planes:
var planes = [];
for (i = 0; i < 20; i++) {
var geometry = new THREE.PlaneGeometry(sizeWidth*((randomSO(1,20)*0.00001)), sizeHeight*((randomSO(1,10)*0.0001)));
var material = new THREE.MeshBasicMaterial( {color: 0x00ff00});
var plane = new THREE.Mesh(geometry, material);
plane.drawMode = THREE.TrianglesDrawMode;
plane.position.set(-10+i, 0, 0);
scene.add(plane);
planes[i] = plane;
}
The X-co-ordinate in above example isn't how I'd want it but is like that for testing. I would like to work according to screensize, that each plane would locate in random % of the width and height. The width of my screen is 1280 and now when I set the the x co-ordinate to let's say -20 it's already out of the screen. Should I set the Z co-ordinate of the camera differently? I really don't understand the position co-ordinates in this :-(

Three.js - position object at vertex of another

I have an IcosahedronGeometry defined like this (with all the code about colors and non-position stuff omitted):
var radius = 200;
geometry = new THREE.IcosahedronGeometry(radius, 2);
var materials = [
new THREE.MeshPhongMaterial({}),
new THREE.MeshBasicMaterial({})
];
group1 = THREE.SceneUtils.createMultiMaterialObject(geometry, materials);
group1.position.x = 0;
// rotate a bit just so it spins off-axis
group1.rotation.x = -1.87;
Which creates an almost spherical, many-sided shape.
I want to place little spheres at just a few of the vertices of this shape. Let's say 10 spheres. I do this by copying 10 vertices into an array, like this:
var vertexArray = [];
for (var i = 0; i < 10; i++) {
vertexArray.push(geometry4.vertices[i])
}
then, I use the Vectors copied into vertexArray to set the positions off Sprites:
for (var i = 0; i < vertexArray.length; i++) {
var loader = new THREE.TextureLoader()
var spriteMaterial = new THREE.SpriteMaterial(
{
map: loader.load('/glow.png'),
blending: THREE.AdditiveBlending,
side: THREE.BackSide
})
var sprite = new THREE.Sprite(spriteMaterial)
sprite.position.set(vertexArray[i].x, vertexArray[i].y, vertexArray[i].z)
// do i need rotate these by the same amount?
sprite.rotation.x = -1.87
scene.add(sprite)
}
This all works fine, except that the Sprites don't line up with the actual vertices on the Icosahedron, they just sit randomly (seemingly) somewhere on the faces. Occasionally a Sprite will sit exactly on a vertex.
Am I copying the vertices wrong, or missing a step in here?

Add an object as a child of a parent object, and the child object will rotate with the parent.
Use this pattern, instead:
var sprite = new THREE.Sprite( spriteMaterial );
sprite.position.copy( vertexArray[i] );
group1.add( sprite );
three.js r.76

Threejs PlaneGeometry doesn't receive shadows or reflections

I'm pretty new to 3d and to threejs and I can't figure out how I can get a PlaneGeometry to show individually illuminated polygons i.e. receive shadows or show reflection. What I basically do is taking a PlaneGeometry applying some noise to every z value of the vertices. Then I have a simple directional light in my scene which is supposed to make the emerging noise pattern on the plane visible. I tried different things like plane.castShadow = true or renderer.shadowMapEnabled = true without success. Am I just missing a simple option or is this way more complicated than I think?
Here's are the relevant pieces of my code
renderer.setSize(width, height);
renderer.setClearColor(0x111111, 1);
...
var directionalLight = new THREE.DirectionalLight( 0xffffff, 0.9);
directionalLight.position.set(10, 2, 20);
directionalLight.castShadow = true;
directionalLight.shadowCameraVisible = true;
scene.add( directionalLight );
var geometry = new THREE.PlaneGeometry(20, 20, segments, segments);
var index = 0;
for(var i=0; i < segments + 1; i++) {
for(var j=0; j < segments + 1; j++) {
zOffset = simplex.noise2D(i * xNoiseScale, j * yNoiseScale) * 5;
geometry.vertices[index].z = zOffset;
index++;
}
}
var material = new THREE.MeshLambertMaterial({
side: THREE.DoubleSide,
color: 0xf50066
});
var plane = new THREE.Mesh(geometry, material);
plane.rotation.x = -Math.PI / 2.35;
plane.castShadow = true;
plane.receiveShadow = true;
scene.add(plane);
This is the output I get. Obviously the plane is aware of the light because the bottom side is darker than the upper side but there is no sign of any individual polygons receiving individual lightening and no 3d structure is visible. Interestingly when I put in a different geometry like a BoxGeometry individual polygons are illuminated individually (see 2nd image). Any ideas?

Ok I figured it out thanks to this post. The trick is to use the THREE.FlatShading shader on the material. Important to note is that after every update of the vertices two things need to be done. Before rendering geometry.normalsNeedUpdate must be set to true so the renderer also incorporates the newly oriented vertices. Also geometry.computeFaceNormals() needs to be called before rendering because when you alter the vertices the normals are not the same anymore.

Threejs, making glass shatter effect

I have an idea to create, but since my knowledge about Three.js and 3D programming in general is limited, I am stuck...
Idea: User is doing some things. At some point - whole front screen crashes, and reveals something different behind.
At the beginning, my idea was - make screenshot, of what is happening right now, put that image in front of everything (still, having difficulties making that plane to take 100% size - idea - when it shows, user cannot tell the difference, between old 3d renderings, and new 2d picture), and then - shatter it. So - by looking around the Web for different examples, I made some... thing - Created screenshot, made plane and applied screenshot as a texture to it. To create shattering effect, I used TessellateModifier to divide that plane, and ExplodeModifier to create each face as separated face.
Here will be the code I made so far.
function drawSS()
{
var img = new Image;
img.onload = function() { // When screenshot is ready
var canvas = document.createElement('canvas');
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
var context = canvas.getContext('2d');
// CANVAS DRAWINGS
// Draws screenshot
// END
var texture = new THREE.Texture(canvas);
texture.needsUpdate = true;
var multiMaterial = [
new THREE.MeshBasicMaterial({map: texture, side: THREE.FrontSide}), // canvas drawings
new THREE.MeshBasicMaterial( { color: 0xffffff, wireframe: true, transparent: true}) // for displaying wireframe
];
var geometry = new THREE.PlaneGeometry(canvas.width, canvas.height); // create plane
for (var i = 0, len = geometry.faces.length; i < len; i++) { // Snippet from some stackoverflow post, that works.
var face = geometry.faces[i].clone();
face.materialIndex = 1;
geometry.faces.push(face);
geometry.faceVertexUvs[0].push(geometry.faceVertexUvs[0][i].slice(0));
}
geometry.dynamic = true;
THREE.GeometryUtils.center( geometry ); // ?
var tessellateModifier = new THREE.TessellateModifier( 10 );
for ( var i = 0; i < 5; i ++ )
tessellateModifier.modify( geometry );
new THREE.ExplodeModifier().modify( geometry );
geometry.vertices[0].x -=300;
geometry.vertices[1].x -=300;
geometry.vertices[2].x -=300;
var mesh = new THREE.Mesh( geometry, new THREE.MeshFaceMaterial(multiMaterial) );
scene.add( mesh );
};
// THEN, set the src
img.src = THREEx.Screenshot.toDataURL(renderer);
}
For now - I moved 1 face, by changing coordinates of 3 vertices. I'm asking - if this approach is the way to go? Result looks like this. (white lines - wireframe, black lines - (drawings in canvas) my desired wireframes - problem for later). Note - by moving this way - texture goes along, I don't know, if I make new triangles using these vertices, how would I set texture.