如何在 Three.js 中更新制服？
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【中文标题】如何在 Three.js 中更新制服？【英文标题】：How do you update a uniform In Three.js? 【发布时间】：2015-07-07 20:49:30 【问题描述】：我不得不重写我的问题，因为我之前问错了问题。
我是想问，怎么更新three.js中的制服？
【问题讨论】：
你似乎有它倒退。每一帧都会更新制服。 哦，哎呀，你是对的，我用错了术语。我想我的问题真的是，如何在不使用 Vector2 或 Vector3 的情况下更新浮动制服？而且我认为无论如何你这样做会更好。 我想我找到了。是吗：yourMesh.material.uniforms.yourUniform.value = 不管； ?我需要注意哪些性能问题？ 所有制服都有一个类型和一个值。更新.value
我觉得你在这里发帖太快了。
【参考方案1】：
这似乎有效：
yourMesh.material.uniforms.yourUniform.value = whatever;
【讨论】：
【参考方案2】：有两种方式：
您可以在Shader Material 本身中更新uniform
或
您可以使用mesh.material 访问ShaderMaterial，然后更新uniform
两种情况的示例：
var delta = 0
var customUniforms =
delta: value: 0 ,
u_time: value: Date.now()
;
// shader material with custom Uniform
shaderMaterial = new THREE.ShaderMaterial(
uniforms: customUniforms,
vertexShader: document.getElementById("vertexShader2").textContent,
fragmentShader: document.getElementById("fragmentShader2").textContent
);
// test Mesh object for shader
var geometry = new THREE.BoxBufferGeometry(10, 10, 10, 10, 10, 10);
shaderMesh = new THREE.Mesh(geometry, shaderMaterial);
this.scene.add(shaderMesh);
在动画循环中
animate = () =>
delta += 0.1;
// Update uniform in Shader Material
shaderMaterial.uniforms.delta.value = 0.5 + Math.sin(delta) * 0.0005;
// Update uniform from Mesh itself
shaderMesh.material.uniforms.u_time.value = delta;
https://codesandbox.io/s/autumn-http-e9wk5
完整示例
<body>
<div id="container"></div>
<script src="js/three.min.js"></script>
<script id="vertexShader" type="x-shader/x-vertex">
void main()
gl_Position = vec4( position, 1.0 );
</script>
<script id="fragmentShader" type="x-shader/x-fragment">
uniform vec2 u_resolution;
uniform float u_time;
void main()
vec2 st = gl_FragCoord.xy/u_resolution.xy;
gl_FragColor=vec4(st.x,st.y,0.0,1.0);
</script>
<script>
var container;
var camera, scene, renderer;
var uniforms;
init();
animate();
function init()
container = document.getElementById( 'container' );
camera = new THREE.Camera();
camera.position.z = 1;
scene = new THREE.Scene();
var geometry = new THREE.PlaneBufferGeometry( 2, 2 );
uniforms =
u_time: type: "f", value: 1.0 ,
u_resolution: type: "v2", value: new THREE.Vector2() ,
u_mouse: type: "v2", value: new THREE.Vector2()
;
var material = new THREE.ShaderMaterial(
uniforms: uniforms,
vertexShader: document.getElementById( 'vertexShader' ).textContent,
fragmentShader: document.getElementById( 'fragmentShader' ).textContent
);
var mesh = new THREE.Mesh( geometry, material );
scene.add( mesh );
renderer = new THREE.WebGLRenderer();
renderer.setPixelRatio( window.devicePixelRatio );
container.appendChild( renderer.domElement );
onWindowResize();
window.addEventListener( 'resize', onWindowResize, false );
document.onmousemove = function(e)
uniforms.u_mouse.value.x = e.pageX
uniforms.u_mouse.value.y = e.pageY
function onWindowResize( event )
renderer.setSize( window.innerWidth, window.innerHeight );
uniforms.u_resolution.value.x = renderer.domElement.width;
uniforms.u_resolution.value.y = renderer.domElement.height;
function animate()
requestAnimationFrame( animate );
render();
function render()
uniforms.u_time.value += 0.05;
renderer.render( scene, camera );
</script>
</body>
【讨论】：
【参考方案3】：更新着色器制服的小例子。
/* Vertex Shader */
<script type="x-shader/x-fragment" id="myShader">
uniform float myuniform;
uniform sampler2D myTexture;
varying vec2 vUV;
varying vec2 ver;
ver = uv *vec2( myuniform, myuniform); // this will be updated on mouse move
gl_Position = projectionMatrix *modelViewMatrix * vec4(position,1.0);
</script>
/* Set uniform */
var myUniform;
var myTexture = new THREE.ImageUtils.loadTexture( './data/textures/theTexture.jpg' );
_uniforms =
myUniform: type: "f", value: myUniform ,
myTexture: type: "t", value: myTexture ,
;
customMaterial = new THREE.ShaderMaterial(
uniforms: _uniforms,
vertexShader: document.getElementById( 'myShader' ).textContent,
fragmentShader: document.getElementById( 'fragmentShader' ).textContent,
wireframe: false,
side: THREE.FrontSide
);
document.addEventListener( 'mousemove', onDocumentMouseMove, false );
function onDocumentMouseMove(ev)
uniforms.myUniform.value += 0.01; // Updates this new value
uniforms.myUniform.needsUpdate = true;
...
【讨论】：
【参考方案4】：对于我的用例来说，这似乎是一个很好的方法：
const mat = new THREE.ShaderMaterial(
uniforms:
customVec3Uniform: value: new THREE.Vector3(1,1,1)
,
vertexShader: document.getElementById('vertexShader').textContent,
fragmentShader: document.getElementById('fragmentShader').textContent,
);
关于运行时更新（citation）：
mat.uniforms.customVec3Uniform.value = new THREE.Vector3(2,2,2);
// mat.needsUpdate = true; // my example works without 'needsUpdate'
【讨论】：
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