webgl_gpgpu_birds_gltf
对应 three.js 示例地址 。
仅需关注 init 函数的内容，其他部分都是示例小程序所使用的描述配置。
js
import * as THREE from "three";
import { GLTFLoader } from "three/examples/jsm/loaders/GLTFLoader.js";
import { GPUComputationRenderer } from "three/examples/jsm/misc/GPUComputationRenderer.js";
/** @type {import("@minisheeep/mp-three-examples").OfficialExampleInfo} */
const exampleInfo = {
name: "webgl_gpgpu_birds_gltf",
useLoaders: [GLTFLoader],
info: [
[
{
tag: "a",
link: "https://threejs.org",
content: "three.js"
},
{
tag: "text",
content: "- webgl gpgpu birds + GLTF mesh"
}
],
[
{
tag: "text",
content: "Flamingo by"
},
{
tag: "a",
link: "https://mirada.com/",
content: "mirada"
},
{
tag: "text",
content: "from"
},
{
tag: "a",
link: "http://www.ro.me/",
content: "rome"
}
],
[
{
tag: "text",
content: "Move mouse to disturb birds."
}
]
],
init: ({ window, canvas, GUI, Stats, needToDispose, useFrame }) => {
const fragmentShaderVelocity = `
uniform float time;
uniform float testing;
uniform float delta; // about 0.016
uniform float separationDistance; // 20
uniform float alignmentDistance; // 40
uniform float cohesionDistance; //
uniform float freedomFactor;
uniform vec3 predator;
const float width = resolution.x;
const float height = resolution.y;
const float PI = 3.141592653589793;
const float PI_2 = PI * 2.0;
// const float VISION = PI * 0.55;
float zoneRadius = 40.0;
float zoneRadiusSquared = 1600.0;
float separationThresh = 0.45;
float alignmentThresh = 0.65;
const float UPPER_BOUNDS = BOUNDS;
const float LOWER_BOUNDS = -UPPER_BOUNDS;
const float SPEED_LIMIT = 9.0;
float rand( vec2 co ){
return fract( sin( dot( co.xy, vec2(12.9898,78.233) ) ) * 43758.5453 );
}
void main() {
zoneRadius = separationDistance + alignmentDistance + cohesionDistance;
separationThresh = separationDistance / zoneRadius;
alignmentThresh = ( separationDistance + alignmentDistance ) / zoneRadius;
zoneRadiusSquared = zoneRadius * zoneRadius;
vec2 uv = gl_FragCoord.xy / resolution.xy;
vec3 birdPosition, birdVelocity;
vec3 selfPosition = texture2D( texturePosition, uv ).xyz;
vec3 selfVelocity = texture2D( textureVelocity, uv ).xyz;
float dist;
vec3 dir; // direction
float distSquared;
float separationSquared = separationDistance * separationDistance;
float cohesionSquared = cohesionDistance * cohesionDistance;
float f;
float percent;
vec3 velocity = selfVelocity;
float limit = SPEED_LIMIT;
dir = predator * UPPER_BOUNDS - selfPosition;
dir.z = 0.;
// dir.z *= 0.6;
dist = length( dir );
distSquared = dist * dist;
float preyRadius = 150.0;
float preyRadiusSq = preyRadius * preyRadius;
// move birds away from predator
if ( dist < preyRadius ) {
f = ( distSquared / preyRadiusSq - 1.0 ) * delta * 100.;
velocity += normalize( dir ) * f;
limit += 5.0;
}
// if (testing == 0.0) {}
// if ( rand( uv + time ) < freedomFactor ) {}
// Attract flocks to the center
vec3 central = vec3( 0., 0., 0. );
dir = selfPosition - central;
dist = length( dir );
dir.y *= 2.5;
velocity -= normalize( dir ) * delta * 5.;
for ( float y = 0.0; y < height; y++ ) {
for ( float x = 0.0; x < width; x++ ) {
vec2 ref = vec2( x + 0.5, y + 0.5 ) / resolution.xy;
birdPosition = texture2D( texturePosition, ref ).xyz;
dir = birdPosition - selfPosition;
dist = length( dir );
if ( dist < 0.0001 ) continue;
distSquared = dist * dist;
if ( distSquared > zoneRadiusSquared ) continue;
percent = distSquared / zoneRadiusSquared;
if ( percent < separationThresh ) { // low
// Separation - Move apart for comfort
f = ( separationThresh / percent - 1.0 ) * delta;
velocity -= normalize( dir ) * f;
} else if ( percent < alignmentThresh ) { // high
// Alignment - fly the same direction
float threshDelta = alignmentThresh - separationThresh;
float adjustedPercent = ( percent - separationThresh ) / threshDelta;
birdVelocity = texture2D( textureVelocity, ref ).xyz;
f = ( 0.5 - cos( adjustedPercent * PI_2 ) * 0.5 + 0.5 ) * delta;
velocity += normalize( birdVelocity ) * f;
} else {
// Attraction / Cohesion - move closer
float threshDelta = 1.0 - alignmentThresh;
float adjustedPercent;
if( threshDelta == 0. ) adjustedPercent = 1.;
else adjustedPercent = ( percent - alignmentThresh ) / threshDelta;
f = ( 0.5 - ( cos( adjustedPercent * PI_2 ) * -0.5 + 0.5 ) ) * delta;
velocity += normalize( dir ) * f;
}
}
}
// this make tends to fly around than down or up
// if (velocity.y > 0.) velocity.y *= (1. - 0.2 * delta);
// Speed Limits
if ( length( velocity ) > limit ) {
velocity = normalize( velocity ) * limit;
}
gl_FragColor = vec4( velocity, 1.0 );
}
`;
const fragmentShaderPosition = `
uniform float time;
uniform float delta;
void main() {
vec2 uv = gl_FragCoord.xy / resolution.xy;
vec4 tmpPos = texture2D( texturePosition, uv );
vec3 position = tmpPos.xyz;
vec3 velocity = texture2D( textureVelocity, uv ).xyz;
float phase = tmpPos.w;
phase = mod( ( phase + delta +
length( velocity.xz ) * delta * 3. +
max( velocity.y, 0.0 ) * delta * 6. ), 62.83 );
gl_FragColor = vec4( position + velocity * delta * 15. , phase );
}
`;
const WIDTH = 64;
const BIRDS = WIDTH * WIDTH;
const BirdGeometry = new THREE.BufferGeometry();
let textureAnimation, durationAnimation, birdMesh, materialShader, indicesPerBird;
function nextPowerOf2(n) {
return Math.pow(2, Math.ceil(Math.log(n) / Math.log(2)));
}
Math.lerp = function(value1, value2, amount) {
amount = Math.max(Math.min(amount, 1), 0);
return value1 + (value2 - value1) * amount;
};
const gltfs = ["models/gltf/Parrot.glb", "models/gltf/Flamingo.glb"];
const colors = [13434879, 16768767];
const sizes = [0.2, 0.1];
const selectModel = Math.floor(Math.random() * gltfs.length);
new GLTFLoader().load(gltfs[selectModel], function(gltf) {
const animations = gltf.animations;
durationAnimation = Math.round(animations[0].duration * 60);
const birdGeo = gltf.scene.children[0].geometry;
const morphAttributes = birdGeo.morphAttributes.position;
const tHeight = nextPowerOf2(durationAnimation);
const tWidth = nextPowerOf2(birdGeo.getAttribute("position").count);
indicesPerBird = birdGeo.index.count;
const tData = new Float32Array(4 * tWidth * tHeight);
for (let i = 0; i < tWidth; i++) {
for (let j = 0; j < tHeight; j++) {
const offset = j * tWidth * 4;
const curMorph = Math.floor(j / durationAnimation * morphAttributes.length);
const nextMorph = (Math.floor(j / durationAnimation * morphAttributes.length) + 1) % morphAttributes.length;
const lerpAmount = j / durationAnimation * morphAttributes.length % 1;
if (j < durationAnimation) {
let d0, d1;
d0 = morphAttributes[curMorph].array[i * 3];
d1 = morphAttributes[nextMorph].array[i * 3];
if (d0 !== void 0 && d1 !== void 0)
tData[offset + i * 4] = Math.lerp(d0, d1, lerpAmount);
d0 = morphAttributes[curMorph].array[i * 3 + 1];
d1 = morphAttributes[nextMorph].array[i * 3 + 1];
if (d0 !== void 0 && d1 !== void 0)
tData[offset + i * 4 + 1] = Math.lerp(d0, d1, lerpAmount);
d0 = morphAttributes[curMorph].array[i * 3 + 2];
d1 = morphAttributes[nextMorph].array[i * 3 + 2];
if (d0 !== void 0 && d1 !== void 0)
tData[offset + i * 4 + 2] = Math.lerp(d0, d1, lerpAmount);
tData[offset + i * 4 + 3] = 1;
}
}
}
textureAnimation = new THREE.DataTexture(
tData,
tWidth,
tHeight,
THREE.RGBAFormat,
THREE.FloatType
);
textureAnimation.needsUpdate = true;
const vertices = [], color = [], reference = [], seeds = [], indices = [];
const totalVertices = birdGeo.getAttribute("position").count * 3 * BIRDS;
for (let i = 0; i < totalVertices; i++) {
const bIndex = i % (birdGeo.getAttribute("position").count * 3);
vertices.push(birdGeo.getAttribute("position").array[bIndex]);
color.push(birdGeo.getAttribute("color").array[bIndex]);
}
let r = Math.random();
for (let i = 0; i < birdGeo.getAttribute("position").count * BIRDS; i++) {
const bIndex = i % birdGeo.getAttribute("position").count;
const bird = Math.floor(i / birdGeo.getAttribute("position").count);
if (bIndex == 0) r = Math.random();
const j = ~~bird;
const x = j % WIDTH / WIDTH;
const y = ~~(j / WIDTH) / WIDTH;
reference.push(x, y, bIndex / tWidth, durationAnimation / tHeight);
seeds.push(bird, r, Math.random(), Math.random());
}
for (let i = 0; i < birdGeo.index.array.length * BIRDS; i++) {
const offset = Math.floor(i / birdGeo.index.array.length) * birdGeo.getAttribute("position").count;
indices.push(birdGeo.index.array[i % birdGeo.index.array.length] + offset);
}
BirdGeometry.setAttribute(
"position",
new THREE.BufferAttribute(new Float32Array(vertices), 3)
);
BirdGeometry.setAttribute("birdColor", new THREE.BufferAttribute(new Float32Array(color), 3));
BirdGeometry.setAttribute("color", new THREE.BufferAttribute(new Float32Array(color), 3));
BirdGeometry.setAttribute(
"reference",
new THREE.BufferAttribute(new Float32Array(reference), 4)
);
BirdGeometry.setAttribute("seeds", new THREE.BufferAttribute(new Float32Array(seeds), 4));
BirdGeometry.setIndex(indices);
init();
});
let stats;
let camera, scene, renderer;
let mouseX = 0, mouseY = 0;
let windowHalfX = window.innerWidth / 2;
let windowHalfY = window.innerHeight / 2;
const BOUNDS = 800, BOUNDS_HALF = BOUNDS / 2;
let last = Date.now();
let gpuCompute;
let velocityVariable;
let positionVariable;
let positionUniforms;
let velocityUniforms;
function init() {
camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 1, 3e3);
camera.position.z = 350;
scene = new THREE.Scene();
scene.background = new THREE.Color(colors[selectModel]);
scene.fog = new THREE.Fog(colors[selectModel], 100, 1e3);
const hemiLight = new THREE.HemisphereLight(colors[selectModel], 16777215, 4.5);
hemiLight.color.setHSL(0.6, 1, 0.6, THREE.SRGBColorSpace);
hemiLight.groundColor.setHSL(0.095, 1, 0.75, THREE.SRGBColorSpace);
hemiLight.position.set(0, 50, 0);
scene.add(hemiLight);
const dirLight = new THREE.DirectionalLight(52945, 2);
dirLight.color.setHSL(0.1, 1, 0.95, THREE.SRGBColorSpace);
dirLight.position.set(-1, 1.75, 1);
dirLight.position.multiplyScalar(30);
scene.add(dirLight);
renderer = new THREE.WebGLRenderer({ antialias: true, canvas });
renderer.setPixelRatio(window.devicePixelRatio);
renderer.setSize(window.innerWidth, window.innerHeight);
renderer.setAnimationLoop(animate);
initComputeRenderer();
stats = new Stats(renderer);
canvas.addEventListener("pointermove", onPointerMove);
window.addEventListener("resize", onWindowResize);
const gui = new GUI();
const effectController = {
separation: 20,
alignment: 20,
cohesion: 20,
freedom: 0.75,
size: sizes[selectModel],
count: Math.floor(BIRDS / 4)
};
const valuesChanger = function() {
velocityUniforms["separationDistance"].value = effectController.separation;
velocityUniforms["alignmentDistance"].value = effectController.alignment;
velocityUniforms["cohesionDistance"].value = effectController.cohesion;
velocityUniforms["freedomFactor"].value = effectController.freedom;
if (materialShader) materialShader.uniforms["size"].value = effectController.size;
BirdGeometry.setDrawRange(0, indicesPerBird * effectController.count);
};
valuesChanger();
gui.add(effectController, "separation", 0, 100, 1).onChange(valuesChanger);
gui.add(effectController, "alignment", 0, 100, 1e-3).onChange(valuesChanger);
gui.add(effectController, "cohesion", 0, 100, 0.025).onChange(valuesChanger);
gui.add(effectController, "size", 0, 1, 0.01).onChange(valuesChanger);
gui.add(effectController, "count", 0, BIRDS, 1).onChange(valuesChanger);
gui.close();
initBirds(effectController);
}
function initComputeRenderer() {
gpuCompute = new GPUComputationRenderer(WIDTH, WIDTH, renderer);
const dtPosition = gpuCompute.createTexture();
const dtVelocity = gpuCompute.createTexture();
fillPositionTexture(dtPosition);
fillVelocityTexture(dtVelocity);
velocityVariable = gpuCompute.addVariable(
"textureVelocity",
fragmentShaderVelocity,
dtVelocity
);
positionVariable = gpuCompute.addVariable(
"texturePosition",
fragmentShaderPosition,
dtPosition
);
gpuCompute.setVariableDependencies(velocityVariable, [positionVariable, velocityVariable]);
gpuCompute.setVariableDependencies(positionVariable, [positionVariable, velocityVariable]);
positionUniforms = positionVariable.material.uniforms;
velocityUniforms = velocityVariable.material.uniforms;
positionUniforms["time"] = { value: 0 };
positionUniforms["delta"] = { value: 0 };
velocityUniforms["time"] = { value: 1 };
velocityUniforms["delta"] = { value: 0 };
velocityUniforms["testing"] = { value: 1 };
velocityUniforms["separationDistance"] = { value: 1 };
velocityUniforms["alignmentDistance"] = { value: 1 };
velocityUniforms["cohesionDistance"] = { value: 1 };
velocityUniforms["freedomFactor"] = { value: 1 };
velocityUniforms["predator"] = { value: new THREE.Vector3() };
velocityVariable.material.defines.BOUNDS = BOUNDS.toFixed(2);
velocityVariable.wrapS = THREE.RepeatWrapping;
velocityVariable.wrapT = THREE.RepeatWrapping;
positionVariable.wrapS = THREE.RepeatWrapping;
positionVariable.wrapT = THREE.RepeatWrapping;
const error = gpuCompute.init();
if (error !== null) {
console.error(error);
}
}
function initBirds(effectController) {
const geometry = BirdGeometry;
const m = new THREE.MeshStandardMaterial({
vertexColors: true,
flatShading: true,
roughness: 1,
metalness: 0
});
m.onBeforeCompile = (shader) => {
shader.uniforms.texturePosition = { value: null };
shader.uniforms.textureVelocity = { value: null };
shader.uniforms.textureAnimation = { value: textureAnimation };
shader.uniforms.time = { value: 1 };
shader.uniforms.size = { value: effectController.size };
shader.uniforms.delta = { value: 0 };
let token = "#define STANDARD";
let insert = (
/* glsl */
`
attribute vec4 reference;
attribute vec4 seeds;
attribute vec3 birdColor;
uniform sampler2D texturePosition;
uniform sampler2D textureVelocity;
uniform sampler2D textureAnimation;
uniform float size;
uniform float time;
`
);
shader.vertexShader = shader.vertexShader.replace(token, token + insert);
token = "#include <begin_vertex>";
insert = /* glsl */
`
vec4 tmpPos = texture2D( texturePosition, reference.xy );
vec3 pos = tmpPos.xyz;
vec3 velocity = normalize(texture2D( textureVelocity, reference.xy ).xyz);
vec3 aniPos = texture2D( textureAnimation, vec2( reference.z, mod( time + ( seeds.x ) * ( ( 0.0004 + seeds.y / 10000.0) + normalize( velocity ) / 20000.0 ), reference.w ) ) ).xyz;
vec3 newPosition = position;
newPosition = mat3( modelMatrix ) * ( newPosition + aniPos );
newPosition *= size + seeds.y * size * 0.2;
velocity.z *= -1.;
float xz = length( velocity.xz );
float xyz = 1.;
float x = sqrt( 1. - velocity.y * velocity.y );
float cosry = velocity.x / xz;
float sinry = velocity.z / xz;
float cosrz = x / xyz;
float sinrz = velocity.y / xyz;
mat3 maty = mat3( cosry, 0, -sinry, 0 , 1, 0 , sinry, 0, cosry );
mat3 matz = mat3( cosrz , sinrz, 0, -sinrz, cosrz, 0, 0 , 0 , 1 );
newPosition = maty * matz * newPosition;
newPosition += pos;
vec3 transformed = vec3( newPosition );
`;
shader.vertexShader = shader.vertexShader.replace(token, insert);
materialShader = shader;
};
birdMesh = new THREE.Mesh(geometry, m);
birdMesh.rotation.y = Math.PI / 2;
birdMesh.castShadow = true;
birdMesh.receiveShadow = true;
scene.add(birdMesh);
}
function fillPositionTexture(texture) {
const theArray = texture.image.data;
for (let k = 0, kl = theArray.length; k < kl; k += 4) {
const x = Math.random() * BOUNDS - BOUNDS_HALF;
const y = Math.random() * BOUNDS - BOUNDS_HALF;
const z = Math.random() * BOUNDS - BOUNDS_HALF;
theArray[k + 0] = x;
theArray[k + 1] = y;
theArray[k + 2] = z;
theArray[k + 3] = 1;
}
}
function fillVelocityTexture(texture) {
const theArray = texture.image.data;
for (let k = 0, kl = theArray.length; k < kl; k += 4) {
const x = Math.random() - 0.5;
const y = Math.random() - 0.5;
const z = Math.random() - 0.5;
theArray[k + 0] = x * 10;
theArray[k + 1] = y * 10;
theArray[k + 2] = z * 10;
theArray[k + 3] = 1;
}
}
function onWindowResize() {
windowHalfX = window.innerWidth / 2;
windowHalfY = window.innerHeight / 2;
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize(window.innerWidth, window.innerHeight);
}
function onPointerMove(event) {
if (event.isPrimary === false) return;
mouseX = event.clientX - windowHalfX;
mouseY = event.clientY - windowHalfY;
}
function animate() {
render();
stats.update();
}
function render() {
const now = Date.now();
let delta = (now - last) / 1e3;
if (delta > 1) delta = 1;
last = now;
positionUniforms["time"].value = now;
positionUniforms["delta"].value = delta;
velocityUniforms["time"].value = now;
velocityUniforms["delta"].value = delta;
if (materialShader) materialShader.uniforms["time"].value = now / 1e3;
if (materialShader) materialShader.uniforms["delta"].value = delta;
velocityUniforms["predator"].value.set(
0.5 * mouseX / windowHalfX,
-0.5 * mouseY / windowHalfY,
0
);
mouseX = 1e4;
mouseY = 1e4;
gpuCompute.compute();
if (materialShader)
materialShader.uniforms["texturePosition"].value = gpuCompute.getCurrentRenderTarget(positionVariable).texture;
if (materialShader)
materialShader.uniforms["textureVelocity"].value = gpuCompute.getCurrentRenderTarget(velocityVariable).texture;
renderer.render(scene, camera);
}
}
};
export {
exampleInfo as default
};ts
import { Loader, TypedArray } from 'three';
/**
* 官网示例的多端使用封装把版本
* */
export interface OfficialExampleInfo extends MiniProgramMeta {
/*** 示例名称（保持和官网一致）*/
name: string;
/** main */
init: (context: LoadContext) => void;
}
export interface LoadContext {
//为了减少官方代码的改动，实际上等同于 canvas
window: EventTarget & { innerWidth: number; innerHeight: number; devicePixelRatio: number };
/** HTMLCanvasElement */
canvas: any;
/** https://www.npmjs.com/package/lil-gui */
GUI: any;
/**
* https://www.npmjs.com/package/stats.js
* 也可以使用其他受支持的版本
* */
Stats: any;
/** 收集需要 dispose 的对象（官方示例没有处理这部分）*/
needToDispose: (...objs: any[]) => void | ((fromFn: () => any[]) => void);
/**基于 raq 的通用封装 */
useFrame(animateFunc: (/** ms */ delta: number) => void): { cancel: () => void };
/** 显示加载模态框 */
requestLoading(text?: string): Promise<void>;
/** 隐藏加载模态框*/
cancelLoading(): void;
/** 保存文件的通用封装*/
saveFile(
fileName: string,
data: ArrayBuffer | TypedArray | DataView | string
): Promise<string | null>;
/** 示例使用 DracoDecoder 时的资源路径 */
DecoderPath: {
GLTF: string;
STANDARD: string;
};
/** 为资源路径拼上 CDN 前缀 */
withCDNPrefix(path: string): string;
/**
* 在小程序中应使用 import { VideoTexture } from '@minisheep/three-platform-adapter/override/jsm/textures/VideoTexture.js';
* 正常情况（web） 可直接使用 THREE.VideoTexture
* */
getVideoTexture(videoOptions: VideoOptions): Promise<[{ isVideoTexture: true }, video: any]>;
/**
* 在小程序中应使用 import { CameraTexture } from '@minisheep/three-platform-adapter/override/jsm/textures/CameraTexture.js';
* 正常情况（web） 可参考示例 webgl_materials_video_webcam
* */
getCameraTexture(): { isVideoTexture: true };
/** 用于动态修改 info 中的占位符*/
bindInfoText(template: `$${string}$`, initValue?: string): { value: string };
/** 分屏控件对应的事件回调 */
onSlideStart(handle: () => void): void;
/** 分屏控件对应的事件回调 */
onSlideEnd(handle: () => void): void;
/** 分屏控件对应的事件回调 */
onSlideChange(handle: (offset: number, boxSize: number) => void): void;
}
export type VideoOptions = {
src: string;
/** 相当于 HTMLVideoElement 的 naturalWidth (小程序中获取不到)*/
width: number;
/** 相当于 HTMLVideoElement 的 naturalHeight (小程序中获取不到)*/
height: number;
loop?: boolean;
autoplay?: boolean;
muted?: boolean;
};
/** 示例小程序中使用的一些配置 */
export interface MiniProgramMeta {
/** 用于统计加载相关信息 */
useLoaders: Loader[];
/** 通用 info */
info: TagItem[][];
/** 特殊 info */
infoPanel?: {
left?: [string, string][];
right?: [string, string][];
};
/** 分屏控件配置 */
needSlider?: {
/** 方向 */
direction?: 'horizontal' | 'vertical';
/** 初始偏移 0-100 */
initPosition?: number;
};
/** 操作摇杆控件 */
needArrowControls?: boolean;
/** 默认需要的画布类型 */
canvasType?: '2d' | 'webgl' | 'webgl2';
/** 为保持效果一致所需要的画布样式 */
canvasStyle?: {
bgColor?: string;
width?: number | string;
height?: number | string;
};
/** 部分示例需要在加载前进行一些提示 */
initAfterConfirm?: {
/**
* 提示类型
* @default 'default'
* */
type?: 'warning' | 'default';
text: string[];
};
}
export interface BaseTag<T extends string> {
tag: T;
content: string;
}
export interface ATag extends BaseTag<'a'> {
link: string;
}
export type TextTag = BaseTag<'text'>;
export type TagItem = TextTag | ATag;