"use client";
import { memo, useEffect, useRef, useState } from "react";
import { Renderer, Program, Mesh, Geometry, Triangle } from "ogl";
import { useAnimationLoop, type Metrics } from "@/hooks/use-animation-loop";
export interface WarpRunProps {
density?: "150" | "300" | "400" | "700";
streakColor?: string;
accentColor?: string;
backgroundColor?: string;
speed?: number;
streakLength?: number;
steer?: number;
rollOnDrag?: boolean;
paused?: boolean;
reducedMotion?: boolean;
className?: string;
}
export type WarpDensity = NonNullable<WarpRunProps["density"]>;
const COUNTS: Record<string, number> = {
"150": 150,
"300": 300,
"400": 400,
"700": 700,
};
const hexToRgb01 = (hex: string): [number, number, number] => {
const h = hex.replace("#", "");
const full = h.length === 3 ? h.split("").map((c) => c + c).join("") : h;
const n = parseInt(full, 16);
if (Number.isNaN(n) || full.length !== 6) return [1, 1, 1];
return [((n >> 16) & 255) / 255, ((n >> 8) & 255) / 255, (n & 255) / 255];
};
const DIST_WRAP = 10;
function buildStars(n: number): {
aPoint: Float32Array;
aCorner: Float32Array;
index: Uint16Array;
} {
const aPoint = new Float32Array(n * 4 * 4);
const aCorner = new Float32Array(n * 4 * 2);
const index = new Uint16Array(n * 6);
for (let i = 0; i < n; i++) {
const a = Math.random() * Math.PI * 2;
const r = 0.18 + Math.sqrt(Math.random()) * 1.5;
const x = Math.cos(a) * r;
const y = Math.sin(a) * r;
const z = Math.random();
const sf = 0.7 + Math.round(Math.random() * 6) * 0.1;
for (let v = 0; v < 4; v++) {
const j = (i * 4 + v) * 4;
aPoint[j] = x;
aPoint[j + 1] = y;
aPoint[j + 2] = z;
aPoint[j + 3] = sf;
aCorner[(i * 4 + v) * 2] = v >> 1;
aCorner[(i * 4 + v) * 2 + 1] = (v & 1) * 2 - 1;
}
const b = i * 4;
const k = i * 6;
index[k] = b;
index[k + 1] = b + 1;
index[k + 2] = b + 2;
index[k + 3] = b + 2;
index[k + 4] = b + 1;
index[k + 5] = b + 3;
}
return { aPoint, aCorner, index };
}
const vert = `#version 300 es
in vec4 aPoint;
in vec2 aCorner;
uniform float uDist;
uniform float uSpeed;
uniform float uStreak;
uniform float uZoom;
uniform float uAspect;
uniform float uPx;
uniform float uRoll;
uniform vec2 uSteer;
uniform vec2 uPointer;
out float vFade;
out float vFast;
out float vAlong;
out float vSide;
out float vBright;
vec2 project(vec2 p, float z) {
// Isotropic screen units (height = 2); x is divided by aspect at the end,
// after the width has been applied, so a streak's thickness is the same on
// screen whichever way it points.
float persp = 1.0 / max(z, 0.05);
return p * persp * 1.6 * uZoom;
}
void main() {
// Depth cycles 0 (far) -> 1 (near). fract() IS the recycle.
float depth = fract(aPoint.z + uDist * aPoint.w);
float zNear = 0.55;
float zFar = 13.0;
float z = mix(zFar, zNear, depth);
// Tail lags the head by an amount that GROWS as the star approaches: closer
// stars have more apparent velocity, so longer tails are what sell the
// acceleration.
float len = uStreak * (0.3 + depth * 1.6);
vec2 p = aPoint.xy;
// Steering: the whole tunnel shears opposite the pointer, scaled by depth,
// so distant streaks converge on the cursor exactly like a camera yawing.
p -= uPointer * depth * 1.15;
// Bank rolls the frame about the view axis.
float cr = cos(uRoll), sr = sin(uRoll);
p = vec2(p.x * cr - p.y * sr, p.x * sr + p.y * cr);
vec2 head = project(p, z);
vec2 tail = project(p, z + len);
vec2 dir = head - tail;
float L = length(dir);
dir = L > 1e-5 ? dir / L : vec2(0.0, 1.0);
vec2 nrm = vec2(-dir.y, dir.x);
// Width: a thread far away, a bar up close — but never under a pixel and a
// half, or the far field aliases into dust.
float w = max(uPx * 1.5, 0.003 + depth * depth * 0.024);
vec2 pos = mix(head, tail, aCorner.x) + nrm * aCorner.y * w * 0.5;
pos.x /= uAspect;
pos += uSteer * 0.22;
gl_Position = vec4(pos, 0.0, 1.0);
vAlong = aCorner.x;
vSide = aCorner.y;
// Alpha ramps hide both ends of the cycle: birth pops otherwise, and the
// fly-past clip at the near plane otherwise reads as a glitch.
float born = smoothstep(0.0, 0.10, depth);
float died = 1.0 - smoothstep(0.86, 1.0, depth);
vFade = born * died;
// Far stars are dim; each star also carries its own magnitude so the field
// is not seven hundred identical bulbs.
float mag = fract(sin(aPoint.z * 91.7 + aPoint.x * 13.3) * 43758.5453);
vBright = mix(0.3, 1.0, depth) * (0.55 + 0.45 * mag);
// Velocity readout: only stars genuinely running hot earn the accent.
vFast = clamp((uSpeed * aPoint.w - 0.95) * 1.4, 0.0, 1.0);
}`;
const frag = `#version 300 es
precision highp float;
in float vFade;
in float vFast;
in float vAlong;
in float vSide;
in float vBright;
out vec4 fragColor;
uniform vec3 uStreakCol;
uniform vec3 uAccent;
void main() {
// Across: soft edges, a hot core. Along: head bright, tail dying. The core
// goes toward white — a bright enough light source burns out its own hue.
float across = 1.0 - vSide * vSide;
float along = pow(1.0 - vAlong, 1.6);
float core = pow(across, 4.0) * (1.0 - vAlong);
vec3 col = mix(uStreakCol, uAccent, vFast);
col = mix(col, vec3(1.0), core * 0.55);
float a = min(1.0, across * across * along * vFade * vBright * 1.5);
fragColor = vec4(col, a);
}`;
const backVert = `#version 300 es
in vec2 position;
in vec2 uv;
out vec2 vUv;
void main() { vUv = uv; gl_Position = vec4(position, 0.0, 1.0); }`;
const backFrag = `#version 300 es
precision highp float;
in vec2 vUv;
out vec4 fragColor;
uniform vec3 uBg;
uniform vec3 uStreakCol;
uniform vec3 uAccent;
uniform vec2 uCenter;
uniform float uAspect;
uniform float uGlow;
uniform float uFlow;
float hash(vec2 p) {
return fract(sin(dot(p, vec2(127.1, 311.7))) * 43758.5453);
}
float vnoise(vec2 p) {
vec2 i = floor(p), f = fract(p);
vec2 u = f * f * (3.0 - 2.0 * f);
return mix(
mix(hash(i), hash(i + vec2(1, 0)), u.x),
mix(hash(i + vec2(0, 1)), hash(i + vec2(1, 1)), u.x),
u.y);
}
void main() {
vec2 uv = vUv * 2.0 - 1.0;
vec2 d = (uv - uCenter) * vec2(uAspect, 1.0);
float r = length(d);
vec3 col = uBg;
// Nebula in polar coordinates, log-radial so it streams OUT of the
// vanishing point at the same perspective rate as the stars — the tunnel
// wall going by, not a texture pasted on the glass.
float ang = atan(d.y, d.x);
vec2 nq = vec2(ang * 1.6, log(r + 0.04) * 2.2 - uFlow);
float neb = vnoise(nq) * 0.6 + vnoise(nq * 2.3 + 7.1) * 0.4;
neb = smoothstep(0.35, 0.95, neb) * smoothstep(0.0, 0.45, r);
col += mix(uAccent, uStreakCol, 0.5) * neb * 0.07 * uGlow;
// Bloom at the vanishing point: a tight core and a wide skirt.
float core = exp(-r * r * 60.0) * 0.6 + exp(-r * 5.0) * 0.1;
col += mix(uStreakCol, uAccent, 0.45) * core * uGlow;
// Vignette: the cockpit frame the eye expects at the edges of a run.
col *= 1.0 - 0.3 * smoothstep(0.6, 1.5, length(uv * vec2(uAspect, 1.0)));
// Dither: eight-bit output bands a dark bloom into rings.
col += (hash(gl_FragCoord.xy) - 0.5) / 255.0;
fragColor = vec4(col, 1.0);
}`;
const WarpRun = memo(
({
density = "700",
streakColor = "#e9d5ff",
accentColor = "#67e8f9",
backgroundColor = "#030308",
speed = 0.2,
streakLength = 0.1,
steer = 0.6,
rollOnDrag = true,
paused = false,
reducedMotion = false,
className,
}: WarpRunProps) => {
const containerRef = useRef<HTMLDivElement>(null);
const drawRef = useRef<((dt: number) => void | false) | null>(null);
const measureRef = useRef<((m: Metrics) => void) | null>(null);
const glRef = useRef<WebGLRenderingContext | WebGL2RenderingContext | null>(
null,
);
const roll = useRef({ value: 0, dragging: false, lastX: 0 });
const pointer = useRef({ x: 0, y: 0, tx: 0, ty: 0 });
const [fallback, setFallback] = useState(false);
const pausedRef = useRef(paused);
pausedRef.current = paused;
const loop = useAnimationLoop({
target: containerRef,
halted: paused,
dpr: "auto",
onResize: (metrics) => measureRef.current?.(metrics),
onFrame: ({ dt }) => (drawRef.current ? drawRef.current(dt) : false),
gl: () => glRef.current,
});
const live = useRef({
streakColor, accentColor, backgroundColor,
speed, streakLength, steer, rollOnDrag, reducedMotion,
});
live.current = {
streakColor, accentColor, backgroundColor,
speed, streakLength, steer, rollOnDrag, reducedMotion,
};
useEffect(() => {
const container = containerRef.current;
if (fallback || !container) return;
let renderer: Renderer;
try {
renderer = new Renderer({
alpha: false,
dpr: Math.min(window.devicePixelRatio || 1, 2),
});
} catch {
setFallback(true);
return;
}
const glc = renderer.gl;
glRef.current = glc;
const canvas = glc.canvas as HTMLCanvasElement;
canvas.style.display = "block";
canvas.style.position = "absolute";
canvas.style.top = "0";
canvas.style.left = "0";
container.appendChild(canvas);
const n = COUNTS[density] ?? 400;
const { aPoint, aCorner, index } = buildStars(n);
const geometry = new Geometry(glc, {
aPoint: { size: 4, data: aPoint },
aCorner: { size: 2, data: aCorner },
index: { data: index },
});
const program = new Program(glc, {
vertex: vert,
fragment: frag,
transparent: true,
cullFace: false,
depthTest: false,
depthWrite: false,
uniforms: {
uStreakCol: { value: new Float32Array(hexToRgb01(streakColor)) },
uAccent: { value: new Float32Array(hexToRgb01(accentColor)) },
uDist: { value: 0 },
uSpeed: { value: speed },
uStreak: { value: streakLength },
uZoom: { value: 1 },
uAspect: { value: 1 },
uPx: { value: 2 / 600 },
uRoll: { value: 0 },
uSteer: { value: new Float32Array([0, 0]) },
uPointer: { value: new Float32Array([0, 0]) },
},
});
program.setBlendFunc(glc.SRC_ALPHA, glc.ONE);
const mesh = new Mesh(glc, { geometry, program });
const u = program.uniforms as Record<string, { value: unknown }>;
const backProgram = new Program(glc, {
vertex: backVert,
fragment: backFrag,
cullFace: false,
depthTest: false,
depthWrite: false,
uniforms: {
uBg: { value: new Float32Array(hexToRgb01(backgroundColor)) },
uStreakCol: { value: new Float32Array(hexToRgb01(streakColor)) },
uAccent: { value: new Float32Array(hexToRgb01(accentColor)) },
uCenter: { value: new Float32Array([0, 0]) },
uAspect: { value: 1 },
uGlow: { value: 1 },
uFlow: { value: 0 },
},
});
const back = new Mesh(glc, {
geometry: new Triangle(glc),
program: backProgram,
});
const ub = backProgram.uniforms as Record<string, { value: unknown }>;
let dist = 0;
let flow = 0;
drawRef.current = (dt) => {
const l = live.current;
const step = Math.min(dt, 1 / 30);
const still = pausedRef.current || l.reducedMotion;
if (!still) {
dist = (dist + step * l.speed * 0.09) % DIST_WRAP;
flow = (flow + step * l.speed * 0.35) % 1000;
if (!roll.current.dragging) {
roll.current.value *= Math.pow(0.02, step);
}
const ease = Math.min(1, step * 4.5);
pointer.current.x += (pointer.current.tx - pointer.current.x) * ease;
pointer.current.y += (pointer.current.ty - pointer.current.y) * ease;
}
const steerOn = l.reducedMotion ? 0 : l.steer;
const sx = pointer.current.x * steerOn;
const sy = pointer.current.y * steerOn;
((u.uStreakCol as { value: Float32Array }).value).set(hexToRgb01(l.streakColor));
((u.uAccent as { value: Float32Array }).value).set(hexToRgb01(l.accentColor));
(u.uDist as { value: number }).value = dist;
(u.uSpeed as { value: number }).value = l.speed;
(u.uStreak as { value: number }).value = l.streakLength;
(u.uRoll as { value: number }).value =
l.rollOnDrag ? roll.current.value : 0;
const sv = u.uSteer.value as Float32Array;
sv[0] = sx;
sv[1] = sy;
const pv = u.uPointer.value as Float32Array;
pv[0] = sx;
pv[1] = sy;
((ub.uBg as { value: Float32Array }).value).set(hexToRgb01(l.backgroundColor));
((ub.uStreakCol as { value: Float32Array }).value).set(hexToRgb01(l.streakColor));
((ub.uAccent as { value: Float32Array }).value).set(hexToRgb01(l.accentColor));
const cv = ub.uCenter.value as Float32Array;
cv[0] = sx * 0.22;
cv[1] = sy * 0.22;
(ub.uGlow as { value: number }).value = Math.min(1.6, 0.6 + l.speed * 0.4);
(ub.uFlow as { value: number }).value = flow;
const bg = hexToRgb01(l.backgroundColor);
glc.clearColor(bg[0], bg[1], bg[2], 1);
renderer.render({ scene: back });
renderer.render({ scene: mesh, clear: false });
};
measureRef.current = ({ width, height, dpr }: Metrics) => {
renderer.dpr = dpr;
renderer.setSize(Math.max(1, Math.floor(width)), Math.max(1, Math.floor(height)));
const aspect = Math.max(width, 1) / Math.max(height, 1);
(u.uAspect as { value: number }).value = aspect;
(ub.uAspect as { value: number }).value = aspect;
(u.uPx as { value: number }).value = 2 / Math.max(height * dpr, 1);
drawRef.current?.(0.016);
};
loop.resize();
loop.start();
return () => {
drawRef.current = null;
measureRef.current = null;
if (container.contains(canvas)) container.removeChild(canvas);
};
// eslint-disable-next-line react-hooks/exhaustive-deps
}, [fallback, density]);
useEffect(() => {
loop.paint();
}, [
streakColor, accentColor, backgroundColor, speed,
streakLength, steer, rollOnDrag, loop,
]);
const onPointerDown = (e: React.PointerEvent<HTMLDivElement>) => {
roll.current.dragging = true;
roll.current.lastX = e.clientX;
e.currentTarget.setPointerCapture(e.pointerId);
loop.start();
};
const track = (e: React.PointerEvent<HTMLDivElement>) => {
const r = e.currentTarget.getBoundingClientRect();
if (r.width === 0 || r.height === 0) return;
pointer.current.tx = ((e.clientX - r.left) / r.width) * 2 - 1;
pointer.current.ty = -(((e.clientY - r.top) / r.height) * 2 - 1);
if (!roll.current.dragging) return;
const dx = e.clientX - roll.current.lastX;
roll.current.lastX = e.clientX;
if (live.current.rollOnDrag && !pausedRef.current) {
roll.current.value = Math.max(
-0.55,
Math.min(0.55, roll.current.value - dx * 0.003),
);
}
loop.start();
};
const endDrag = (e: React.PointerEvent<HTMLDivElement>) => {
if (e.currentTarget.hasPointerCapture(e.pointerId)) {
e.currentTarget.releasePointerCapture(e.pointerId);
}
roll.current.dragging = false;
loop.start();
};
const leave = () => {
if (roll.current.dragging) return;
pointer.current.tx = 0;
pointer.current.ty = 0;
loop.start();
};
if (fallback) {
return (
<div
className={className ?? "relative h-full w-full overflow-hidden"}
style={{
backgroundColor,
backgroundImage: `radial-gradient(circle at 50% 50%, ${accentColor}33 0%, transparent 40%), radial-gradient(circle at 50% 50%, ${streakColor}22 0%, transparent 70%)`,
}}
/>
);
}
return (
<div
ref={containerRef}
className={
className ??
"relative h-full w-full cursor-default overflow-hidden [&_canvas]:touch-none select-none"
}
onPointerDown={onPointerDown}
onPointerMove={track}
onPointerUp={endDrag}
onPointerLeave={leave}
onPointerCancel={endDrag}
/>
);
},
);
WarpRun.displayName = "WarpRun";
export default WarpRun;