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- <h1>Custom BufferGeometry</h1>
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- <div class="lesson">
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- <p><a href="/docs/#api/en/core/BufferGeometry"><code class="notranslate" translate="no">BufferGeometry</code></a> is three.js's way of representing all geometry. A <a href="/docs/#api/en/core/BufferGeometry"><code class="notranslate" translate="no">BufferGeometry</code></a>
- essentially a collection <em>named</em> of <a href="/docs/#api/en/core/BufferAttribute"><code class="notranslate" translate="no">BufferAttribute</code></a>s.
- Each <a href="/docs/#api/en/core/BufferAttribute"><code class="notranslate" translate="no">BufferAttribute</code></a> represents an array of one type of data: positions,
- normals, colors, uv, etc... Together, the named <a href="/docs/#api/en/core/BufferAttribute"><code class="notranslate" translate="no">BufferAttribute</code></a>s represent
- <em>parallel arrays</em> of all the data for each vertex.</p>
- <div class="threejs_center"><img src="../resources/threejs-attributes.svg" style="width: 700px"></div>
- <p>Above you can see we have 4 attributes: <code class="notranslate" translate="no">position</code>, <code class="notranslate" translate="no">normal</code>, <code class="notranslate" translate="no">color</code>, <code class="notranslate" translate="no">uv</code>.
- They represent <em>parallel arrays</em> which means that the Nth set of data in each
- attribute belongs to the same vertex. The vertex at index = 4 is highlighted
- to show that the parallel data across all attributes defines one vertex.</p>
- <p>This brings up a point, here's a diagram of a cube with one corner highlighted.</p>
- <div class="threejs_center"><img src="../resources/cube-faces-vertex.svg" style="width: 500px"></div>
- <p>Thinking about it that single corner needs a different normal for each face of the
- cube. A normal is info about which direction something faces. In the diagram
- the normals are presented by the arrows around the corner vertex showing that each
- face that shares that vertex position needs a normal that points in a different direction.</p>
- <p>That corner needs different UVs for each face as well. UVs are texture coordinates
- that specify which part of a texture being drawn on a triangle corresponds to that
- vertex position. You can see the green face needs that vertex to have a UV that corresponds
- to the top right corner of the F texture, the blue face needs a UV that corresponds to the
- top left corner of the F texture, and the red face needs a UV that corresponds to the bottom
- left corner of the F texture.</p>
- <p>A single <em>vertex</em> is the combination of all of its parts. If a vertex needs any
- part to be different then it must be a different vertex.</p>
- <p>As a simple example let's make a cube using <a href="/docs/#api/en/core/BufferGeometry"><code class="notranslate" translate="no">BufferGeometry</code></a>. A cube is interesting
- because it appears to share vertices at the corners but really
- does not. For our example we'll list out all the vertices with all their data
- and then convert that data into parallel arrays and finally use those to make
- <a href="/docs/#api/en/core/BufferAttribute"><code class="notranslate" translate="no">BufferAttribute</code></a>s and add them to a <a href="/docs/#api/en/core/BufferGeometry"><code class="notranslate" translate="no">BufferGeometry</code></a>.</p>
- <p>We start with a list of all the data needed for the cube. Remember again
- that if a vertex has any unique parts it has to be a separate vertex. As such
- to make a cube requires 36 vertices. 2 triangles per face, 3 vertices per triangle,
- 6 faces = 36 vertices.</p>
- <pre class="prettyprint showlinemods notranslate lang-js" translate="no">const vertices = [
- // front
- { pos: [-1, -1, 1], norm: [ 0, 0, 1], uv: [0, 0], },
- { pos: [ 1, -1, 1], norm: [ 0, 0, 1], uv: [1, 0], },
- { pos: [-1, 1, 1], norm: [ 0, 0, 1], uv: [0, 1], },
- { pos: [-1, 1, 1], norm: [ 0, 0, 1], uv: [0, 1], },
- { pos: [ 1, -1, 1], norm: [ 0, 0, 1], uv: [1, 0], },
- { pos: [ 1, 1, 1], norm: [ 0, 0, 1], uv: [1, 1], },
- // right
- { pos: [ 1, -1, 1], norm: [ 1, 0, 0], uv: [0, 0], },
- { pos: [ 1, -1, -1], norm: [ 1, 0, 0], uv: [1, 0], },
- { pos: [ 1, 1, 1], norm: [ 1, 0, 0], uv: [0, 1], },
- { pos: [ 1, 1, 1], norm: [ 1, 0, 0], uv: [0, 1], },
- { pos: [ 1, -1, -1], norm: [ 1, 0, 0], uv: [1, 0], },
- { pos: [ 1, 1, -1], norm: [ 1, 0, 0], uv: [1, 1], },
- // back
- { pos: [ 1, -1, -1], norm: [ 0, 0, -1], uv: [0, 0], },
- { pos: [-1, -1, -1], norm: [ 0, 0, -1], uv: [1, 0], },
- { pos: [ 1, 1, -1], norm: [ 0, 0, -1], uv: [0, 1], },
- { pos: [ 1, 1, -1], norm: [ 0, 0, -1], uv: [0, 1], },
- { pos: [-1, -1, -1], norm: [ 0, 0, -1], uv: [1, 0], },
- { pos: [-1, 1, -1], norm: [ 0, 0, -1], uv: [1, 1], },
- // left
- { pos: [-1, -1, -1], norm: [-1, 0, 0], uv: [0, 0], },
- { pos: [-1, -1, 1], norm: [-1, 0, 0], uv: [1, 0], },
- { pos: [-1, 1, -1], norm: [-1, 0, 0], uv: [0, 1], },
- { pos: [-1, 1, -1], norm: [-1, 0, 0], uv: [0, 1], },
- { pos: [-1, -1, 1], norm: [-1, 0, 0], uv: [1, 0], },
- { pos: [-1, 1, 1], norm: [-1, 0, 0], uv: [1, 1], },
- // top
- { pos: [ 1, 1, -1], norm: [ 0, 1, 0], uv: [0, 0], },
- { pos: [-1, 1, -1], norm: [ 0, 1, 0], uv: [1, 0], },
- { pos: [ 1, 1, 1], norm: [ 0, 1, 0], uv: [0, 1], },
- { pos: [ 1, 1, 1], norm: [ 0, 1, 0], uv: [0, 1], },
- { pos: [-1, 1, -1], norm: [ 0, 1, 0], uv: [1, 0], },
- { pos: [-1, 1, 1], norm: [ 0, 1, 0], uv: [1, 1], },
- // bottom
- { pos: [ 1, -1, 1], norm: [ 0, -1, 0], uv: [0, 0], },
- { pos: [-1, -1, 1], norm: [ 0, -1, 0], uv: [1, 0], },
- { pos: [ 1, -1, -1], norm: [ 0, -1, 0], uv: [0, 1], },
- { pos: [ 1, -1, -1], norm: [ 0, -1, 0], uv: [0, 1], },
- { pos: [-1, -1, 1], norm: [ 0, -1, 0], uv: [1, 0], },
- { pos: [-1, -1, -1], norm: [ 0, -1, 0], uv: [1, 1], },
- ];
- </pre>
- <p>We can then translate all of that into 3 parallel arrays</p>
- <pre class="prettyprint showlinemods notranslate lang-js" translate="no">const positions = [];
- const normals = [];
- const uvs = [];
- for (const vertex of vertices) {
- positions.push(...vertex.pos);
- normals.push(...vertex.norm);
- uvs.push(...vertex.uv);
- }
- </pre>
- <p>Finally we can create a <a href="/docs/#api/en/core/BufferGeometry"><code class="notranslate" translate="no">BufferGeometry</code></a> and then a <a href="/docs/#api/en/core/BufferAttribute"><code class="notranslate" translate="no">BufferAttribute</code></a> for each array
- and add it to the <a href="/docs/#api/en/core/BufferGeometry"><code class="notranslate" translate="no">BufferGeometry</code></a>.</p>
- <pre class="prettyprint showlinemods notranslate lang-js" translate="no"> const geometry = new THREE.BufferGeometry();
- const positionNumComponents = 3;
- const normalNumComponents = 3;
- const uvNumComponents = 2;
- geometry.setAttribute(
- 'position',
- new THREE.BufferAttribute(new Float32Array(positions), positionNumComponents));
- geometry.setAttribute(
- 'normal',
- new THREE.BufferAttribute(new Float32Array(normals), normalNumComponents));
- geometry.setAttribute(
- 'uv',
- new THREE.BufferAttribute(new Float32Array(uvs), uvNumComponents));
- </pre>
- <p>Note that the names are significant. You must name your attributes the names
- that match what three.js expects (unless you are creating a custom shader).
- In this case <code class="notranslate" translate="no">position</code>, <code class="notranslate" translate="no">normal</code>, and <code class="notranslate" translate="no">uv</code>. If you want vertex colors then
- name your attribute <code class="notranslate" translate="no">color</code>.</p>
- <p>Above we created 3 JavaScript native arrays, <code class="notranslate" translate="no">positions</code>, <code class="notranslate" translate="no">normals</code> and <code class="notranslate" translate="no">uvs</code>.
- We then convert those into
- <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray">TypedArrays</a>
- of type <code class="notranslate" translate="no">Float32Array</code>. A <a href="/docs/#api/en/core/BufferAttribute"><code class="notranslate" translate="no">BufferAttribute</code></a> requires a TypedArray not a native
- array. A <a href="/docs/#api/en/core/BufferAttribute"><code class="notranslate" translate="no">BufferAttribute</code></a> also requires you to tell it how many components there
- are per vertex. For the positions and normals we have 3 components per vertex,
- x, y, and z. For the UVs we have 2, u and v.</p>
- <p></p><div translate="no" class="threejs_example_container notranslate">
- <div><iframe class="threejs_example notranslate" translate="no" style=" " src="/manual/examples/resources/editor.html?url=/manual/examples/custom-buffergeometry-cube.html"></iframe></div>
- <a class="threejs_center" href="/manual/examples/custom-buffergeometry-cube.html" target="_blank">Cliquer ici pour ouvrir dans une fenêtre séparée</a>
- </div>
- <p></p>
- <p>That's a lot of data. A small thing we can do is use indices to reference
- the vertices. Looking back at our cube data, each face is made from 2 triangles
- with 3 vertices each, 6 vertices total, but 2 of those vertices are exactly the same;
- The same position, the same normal, and the same uv.
- So, we can remove the matching vertices and then
- reference them by index. First we remove the matching vertices.</p>
- <pre class="prettyprint showlinemods notranslate lang-js" translate="no">const vertices = [
- // front
- { pos: [-1, -1, 1], norm: [ 0, 0, 1], uv: [0, 0], }, // 0
- { pos: [ 1, -1, 1], norm: [ 0, 0, 1], uv: [1, 0], }, // 1
- { pos: [-1, 1, 1], norm: [ 0, 0, 1], uv: [0, 1], }, // 2
- -
- - { pos: [-1, 1, 1], norm: [ 0, 0, 1], uv: [0, 1], },
- - { pos: [ 1, -1, 1], norm: [ 0, 0, 1], uv: [1, 0], },
- { pos: [ 1, 1, 1], norm: [ 0, 0, 1], uv: [1, 1], }, // 3
- // right
- { pos: [ 1, -1, 1], norm: [ 1, 0, 0], uv: [0, 0], }, // 4
- { pos: [ 1, -1, -1], norm: [ 1, 0, 0], uv: [1, 0], }, // 5
- -
- - { pos: [ 1, 1, 1], norm: [ 1, 0, 0], uv: [0, 1], },
- - { pos: [ 1, -1, -1], norm: [ 1, 0, 0], uv: [1, 0], },
- { pos: [ 1, 1, 1], norm: [ 1, 0, 0], uv: [0, 1], }, // 6
- { pos: [ 1, 1, -1], norm: [ 1, 0, 0], uv: [1, 1], }, // 7
- // back
- { pos: [ 1, -1, -1], norm: [ 0, 0, -1], uv: [0, 0], }, // 8
- { pos: [-1, -1, -1], norm: [ 0, 0, -1], uv: [1, 0], }, // 9
- -
- - { pos: [ 1, 1, -1], norm: [ 0, 0, -1], uv: [0, 1], },
- - { pos: [-1, -1, -1], norm: [ 0, 0, -1], uv: [1, 0], },
- { pos: [ 1, 1, -1], norm: [ 0, 0, -1], uv: [0, 1], }, // 10
- { pos: [-1, 1, -1], norm: [ 0, 0, -1], uv: [1, 1], }, // 11
- // left
- { pos: [-1, -1, -1], norm: [-1, 0, 0], uv: [0, 0], }, // 12
- { pos: [-1, -1, 1], norm: [-1, 0, 0], uv: [1, 0], }, // 13
- -
- - { pos: [-1, 1, -1], norm: [-1, 0, 0], uv: [0, 1], },
- - { pos: [-1, -1, 1], norm: [-1, 0, 0], uv: [1, 0], },
- { pos: [-1, 1, -1], norm: [-1, 0, 0], uv: [0, 1], }, // 14
- { pos: [-1, 1, 1], norm: [-1, 0, 0], uv: [1, 1], }, // 15
- // top
- { pos: [ 1, 1, -1], norm: [ 0, 1, 0], uv: [0, 0], }, // 16
- { pos: [-1, 1, -1], norm: [ 0, 1, 0], uv: [1, 0], }, // 17
- -
- - { pos: [ 1, 1, 1], norm: [ 0, 1, 0], uv: [0, 1], },
- - { pos: [-1, 1, -1], norm: [ 0, 1, 0], uv: [1, 0], },
- { pos: [ 1, 1, 1], norm: [ 0, 1, 0], uv: [0, 1], }, // 18
- { pos: [-1, 1, 1], norm: [ 0, 1, 0], uv: [1, 1], }, // 19
- // bottom
- { pos: [ 1, -1, 1], norm: [ 0, -1, 0], uv: [0, 0], }, // 20
- { pos: [-1, -1, 1], norm: [ 0, -1, 0], uv: [1, 0], }, // 21
- -
- - { pos: [ 1, -1, -1], norm: [ 0, -1, 0], uv: [0, 1], },
- - { pos: [-1, -1, 1], norm: [ 0, -1, 0], uv: [1, 0], },
- { pos: [ 1, -1, -1], norm: [ 0, -1, 0], uv: [0, 1], }, // 22
- { pos: [-1, -1, -1], norm: [ 0, -1, 0], uv: [1, 1], }, // 23
- ];
- </pre>
- <p>So now we have 24 unique vertices. Then we specify 36 indices
- for the 36 vertices we need drawn to make 12 triangles by calling <a href="/docs/#api/en/core/BufferGeometry.setIndex"><code class="notranslate" translate="no">BufferGeometry.setIndex</code></a> with an array of indices.</p>
- <pre class="prettyprint showlinemods notranslate lang-js" translate="no">geometry.setAttribute(
- 'position',
- new THREE.BufferAttribute(positions, positionNumComponents));
- geometry.setAttribute(
- 'normal',
- new THREE.BufferAttribute(normals, normalNumComponents));
- geometry.setAttribute(
- 'uv',
- new THREE.BufferAttribute(uvs, uvNumComponents));
- +geometry.setIndex([
- + 0, 1, 2, 2, 1, 3, // front
- + 4, 5, 6, 6, 5, 7, // right
- + 8, 9, 10, 10, 9, 11, // back
- + 12, 13, 14, 14, 13, 15, // left
- + 16, 17, 18, 18, 17, 19, // top
- + 20, 21, 22, 22, 21, 23, // bottom
- +]);
- </pre>
- <p></p><div translate="no" class="threejs_example_container notranslate">
- <div><iframe class="threejs_example notranslate" translate="no" style=" " src="/manual/examples/resources/editor.html?url=/manual/examples/custom-buffergeometry-cube-indexed.html"></iframe></div>
- <a class="threejs_center" href="/manual/examples/custom-buffergeometry-cube-indexed.html" target="_blank">Cliquer ici pour ouvrir dans une fenêtre séparée</a>
- </div>
- <p></p>
- <p><a href="/docs/#api/en/core/BufferGeometry"><code class="notranslate" translate="no">BufferGeometry</code></a> has a <a href="/docs/#api/en/core/BufferGeometry#computeVertexNormals"><code class="notranslate" translate="no">computeVertexNormals</code></a> method for computing normals if you
- are not supplying them. Unfortunately,
- since positions can not be shared if any other part of a vertex is different,
- the results of calling <code class="notranslate" translate="no">computeVertexNormals</code> will generate seams if your
- geometry is supposed to connect to itself like a sphere or a cylinder.</p>
- <div class="spread">
- <div>
- <div data-diagram="bufferGeometryCylinder"></div>
- </div>
- </div>
- <p>For the cylinder above the normals were created using <code class="notranslate" translate="no">computeVertexNormals</code>.
- If you look closely there is a seam on the cylinder. This is because there
- is no way to share the vertices at the start and end of the cylinder since they
- require different UVs so the function to compute them has no idea those are
- the same vertices to smooth over them. Just a small thing to be aware of.
- The solution is to supply your own normals.</p>
- <p>We can also use <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray">TypedArrays</a> from the start instead of native JavaScript arrays.
- The disadvantage to TypedArrays is you must specify their size up front. Of
- course that's not that large of a burden but with native arrays we can just
- <code class="notranslate" translate="no">push</code> values onto them and look at what size they end up by checking their
- <code class="notranslate" translate="no">length</code> at the end. With TypedArrays there is no push function so we need
- to do our own bookkeeping when adding values to them.</p>
- <p>In this example knowing the length up front is pretty easy since we're using
- a big block of static data to start.</p>
- <pre class="prettyprint showlinemods notranslate lang-js" translate="no">-const positions = [];
- -const normals = [];
- -const uvs = [];
- +const numVertices = vertices.length;
- +const positionNumComponents = 3;
- +const normalNumComponents = 3;
- +const uvNumComponents = 2;
- +const positions = new Float32Array(numVertices * positionNumComponents);
- +const normals = new Float32Array(numVertices * normalNumComponents);
- +const uvs = new Float32Array(numVertices * uvNumComponents);
- +let posNdx = 0;
- +let nrmNdx = 0;
- +let uvNdx = 0;
- for (const vertex of vertices) {
- - positions.push(...vertex.pos);
- - normals.push(...vertex.norm);
- - uvs.push(...vertex.uv);
- + positions.set(vertex.pos, posNdx);
- + normals.set(vertex.norm, nrmNdx);
- + uvs.set(vertex.uv, uvNdx);
- + posNdx += positionNumComponents;
- + nrmNdx += normalNumComponents;
- + uvNdx += uvNumComponents;
- }
- geometry.setAttribute(
- 'position',
- - new THREE.BufferAttribute(new Float32Array(positions), positionNumComponents));
- + new THREE.BufferAttribute(positions, positionNumComponents));
- geometry.setAttribute(
- 'normal',
- - new THREE.BufferAttribute(new Float32Array(normals), normalNumComponents));
- + new THREE.BufferAttribute(normals, normalNumComponents));
- geometry.setAttribute(
- 'uv',
- - new THREE.BufferAttribute(new Float32Array(uvs), uvNumComponents));
- + new THREE.BufferAttribute(uvs, uvNumComponents));
- geometry.setIndex([
- 0, 1, 2, 2, 1, 3, // front
- 4, 5, 6, 6, 5, 7, // right
- 8, 9, 10, 10, 9, 11, // back
- 12, 13, 14, 14, 13, 15, // left
- 16, 17, 18, 18, 17, 19, // top
- 20, 21, 22, 22, 21, 23, // bottom
- ]);
- </pre>
- <p></p><div translate="no" class="threejs_example_container notranslate">
- <div><iframe class="threejs_example notranslate" translate="no" style=" " src="/manual/examples/resources/editor.html?url=/manual/examples/custom-buffergeometry-cube-typedarrays.html"></iframe></div>
- <a class="threejs_center" href="/manual/examples/custom-buffergeometry-cube-typedarrays.html" target="_blank">Cliquer ici pour ouvrir dans une fenêtre séparée</a>
- </div>
- <p></p>
- <p>A good reason to use typedarrays is if you want to dynamically update any
- part of the vertices.</p>
- <p>I couldn't think of a really good example of dynamically updating the vertices
- so I decided to make a sphere and move each quad in and out from the center. Hopefully
- it's a useful example.</p>
- <p>Here's the code to generate positions and indices for a sphere. The code
- is sharing vertices within a quad but it's not sharing vertices between
- quads because we want to be able to move each quad separately.</p>
- <p>Because I'm lazy I used a small hierarchy of 3 <a href="/docs/#api/en/core/Object3D"><code class="notranslate" translate="no">Object3D</code></a> objects to compute
- sphere points. How this works is explained in <a href="optimize-lots-of-objects.html">the article on optimizing lots of objects</a>.</p>
- <pre class="prettyprint showlinemods notranslate lang-js" translate="no">function makeSpherePositions(segmentsAround, segmentsDown) {
- const numVertices = segmentsAround * segmentsDown * 6;
- const numComponents = 3;
- const positions = new Float32Array(numVertices * numComponents);
- const indices = [];
- const longHelper = new THREE.Object3D();
- const latHelper = new THREE.Object3D();
- const pointHelper = new THREE.Object3D();
- longHelper.add(latHelper);
- latHelper.add(pointHelper);
- pointHelper.position.z = 1;
- const temp = new THREE.Vector3();
- function getPoint(lat, long) {
- latHelper.rotation.x = lat;
- longHelper.rotation.y = long;
- longHelper.updateMatrixWorld(true);
- return pointHelper.getWorldPosition(temp).toArray();
- }
- let posNdx = 0;
- let ndx = 0;
- for (let down = 0; down < segmentsDown; ++down) {
- const v0 = down / segmentsDown;
- const v1 = (down + 1) / segmentsDown;
- const lat0 = (v0 - 0.5) * Math.PI;
- const lat1 = (v1 - 0.5) * Math.PI;
- for (let across = 0; across < segmentsAround; ++across) {
- const u0 = across / segmentsAround;
- const u1 = (across + 1) / segmentsAround;
- const long0 = u0 * Math.PI * 2;
- const long1 = u1 * Math.PI * 2;
- positions.set(getPoint(lat0, long0), posNdx); posNdx += numComponents;
- positions.set(getPoint(lat1, long0), posNdx); posNdx += numComponents;
- positions.set(getPoint(lat0, long1), posNdx); posNdx += numComponents;
- positions.set(getPoint(lat1, long1), posNdx); posNdx += numComponents;
- indices.push(
- ndx, ndx + 1, ndx + 2,
- ndx + 2, ndx + 1, ndx + 3,
- );
- ndx += 4;
- }
- }
- return {positions, indices};
- }
- </pre>
- <p>We can then call it like this</p>
- <pre class="prettyprint showlinemods notranslate lang-js" translate="no">const segmentsAround = 24;
- const segmentsDown = 16;
- const {positions, indices} = makeSpherePositions(segmentsAround, segmentsDown);
- </pre>
- <p>Because positions returned are unit sphere positions so they are exactly the same
- values we need for normals so we can just duplicated them for the normals.</p>
- <pre class="prettyprint showlinemods notranslate lang-js" translate="no">const normals = positions.slice();
- </pre>
- <p>And then we setup the attributes like before</p>
- <pre class="prettyprint showlinemods notranslate lang-js" translate="no">const geometry = new THREE.BufferGeometry();
- const positionNumComponents = 3;
- const normalNumComponents = 3;
- +const positionAttribute = new THREE.BufferAttribute(positions, positionNumComponents);
- +positionAttribute.setUsage(THREE.DynamicDrawUsage);
- geometry.setAttribute(
- 'position',
- + positionAttribute);
- geometry.setAttribute(
- 'normal',
- new THREE.BufferAttribute(normals, normalNumComponents));
- geometry.setIndex(indices);
- </pre>
- <p>I've highlighted a few differences. We save a reference to the position attribute.
- We also mark it as dynamic. This is a hint to THREE.js that we're going to be changing
- the contents of the attribute often.</p>
- <p>In our render loop we update the positions based off their normals every frame.</p>
- <pre class="prettyprint showlinemods notranslate lang-js" translate="no">const temp = new THREE.Vector3();
- ...
- for (let i = 0; i < positions.length; i += 3) {
- const quad = (i / 12 | 0);
- const ringId = quad / segmentsAround | 0;
- const ringQuadId = quad % segmentsAround;
- const ringU = ringQuadId / segmentsAround;
- const angle = ringU * Math.PI * 2;
- temp.fromArray(normals, i);
- temp.multiplyScalar(THREE.MathUtils.lerp(1, 1.4, Math.sin(time + ringId + angle) * .5 + .5));
- temp.toArray(positions, i);
- }
- positionAttribute.needsUpdate = true;
- </pre>
- <p>And we set <code class="notranslate" translate="no">positionAttribute.needsUpdate</code> to tell THREE.js to use our changes.</p>
- <p></p><div translate="no" class="threejs_example_container notranslate">
- <div><iframe class="threejs_example notranslate" translate="no" style=" " src="/manual/examples/resources/editor.html?url=/manual/examples/custom-buffergeometry-dynamic.html"></iframe></div>
- <a class="threejs_center" href="/manual/examples/custom-buffergeometry-dynamic.html" target="_blank">Cliquer ici pour ouvrir dans une fenêtre séparée</a>
- </div>
- <p></p>
- <p>I hope these were useful examples of how to use <a href="/docs/#api/en/core/BufferGeometry"><code class="notranslate" translate="no">BufferGeometry</code></a> directly to
- make your own geometry and how to dynamically update the contents of a
- <a href="/docs/#api/en/core/BufferAttribute"><code class="notranslate" translate="no">BufferAttribute</code></a>.</p>
- <!-- needed in English only to prevent warning from outdated translations -->
- <p><a href="resources/threejs-geometry.svg"></a></p>
- <p><canvas id="c"></canvas></p>
- <script type="module" src="../resources/threejs-custom-buffergeometry.js"></script>
- </div>
- </div>
- </div>
- <script src="../resources/prettify.js"></script>
- <script src="../resources/lesson.js"></script>
- </body></html>
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