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import * as THREE from "three";
import { useRef, useMemo } from "react";
import { useFrame } from "@react-three/fiber";
export function Meteors({ dateStr }) {
const meshRef = useRef();
const date = new Date(dateStr);
const activeShower = useMemo(() => {}, [dateStr]);
const count = activeShower ? 12 : 3;
const { positions, velocities, lifetimes } = useMemo(() => {
const pos = new Float32Array(count * 3 * 2);
const vel = [];
const life = new Float32Array(count);
for (let i = 0; i < count; i++) {
resetMeteor(i, pos, vel, life, activeShower);
}
return { positions: pos, velocities: vel, lifetimes: life };
}, [activeShower]);
function resetMeteor(i, pos, vel, life, shower) {
const theta = Math.random() * Math.PI * 2;
const phi = Math.acos(2 * Math.random() - 1);
const start = new THREE.Vector3().setFromSphericalCoords(90, phi, theta);
let velocity = new THREE.Vector3();
if (shower) {
const radiant = new THREE.Vector3(...shower.radiant).normalize();
velocity
.subVectors(start, radiant)
.normalize()
.multiplyScalar(1.5 + Math.random());
const angle = start.angleTo(radiant);
if (angle > Math.PI / 1.5 || angle < 0.2) {
resetMeteor(i, pos, vel, life, shower);
return;
}
} else {
velocity
.set(Math.random() - 0.5, Math.random() - 0.5, Math.random() - 0.5)
.normalize()
.multiplyScalar(2.0);
}
pos[i * 6] = start.x;
pos[i * 6 + 1] = start.y;
pos[i * 6 + 2] = start.z;
pos[i * 6 + 3] = start.x;
pos[i * 6 + 4] = start.y;
pos[i * 6 + 5] = start.z;
vel[i] = velocity;
life[i] = Math.random() * 200;
}
useFrame(() => {
if (!meshRef.current) return;
const posAttr = meshRef.current.geometry.attributes.position;
for (let i = 0; i < count; i++) {
lifetimes[i] -= 1.0;
if (lifetimes[i] < 0) {
if (lifetimes[i] > -15) {
const headIdx = i * 6;
const tailIdx = i * 6 + 3;
posAttr.array[tailIdx] = posAttr.array[headIdx] - velocities[i].x * 3;
posAttr.array[tailIdx + 1] =
posAttr.array[headIdx + 1] - velocities[i].y * 3;
posAttr.array[tailIdx + 2] =
posAttr.array[headIdx + 2] - velocities[i].z * 3;
posAttr.array[headIdx] += velocities[i].x;
posAttr.array[headIdx + 1] += velocities[i].y;
posAttr.array[headIdx + 2] += velocities[i].z;
} else {
resetMeteor(i, posAttr.array, velocities, lifetimes, activeShower);
}
}
}
posAttr.needsUpdate = true;
});
return (
<lineSegments ref={meshRef}>
<bufferGeometry>
<bufferAttribute
attach="attributes-position"
count={positions.length / 3}
array={positions}
itemSize={3}
/>
</bufferGeometry>
<lineBasicMaterial
color={activeShower ? "#ccddff" : "#ffffff"}
transparent
opacity={0.5}
linewidth={1}
/>
</lineSegments>
);
}
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