fix: cursor smooth movement on higher refreshrate monitors

src/lib/components/ui/osu-cursor/OsuCursor.svelte

@@ -7,17 +7,26 @@
 
   let { smoothCursor = true }: { smoothCursor?: boolean } = $props();
 
+  const VELOCITY_WINDOW_MS = 16;
+  const SPEED_THRESHOLD = 9;
+  const REQUIRED_CONSECUTIVE = 3;
+
   let mouseX = $state(0);
   let mouseY = $state(0);
-  let lastMouseX = $state(0);
+  let lastMouseX = 0;
-  let lastMouseY = $state(0);
+  let lastMouseY = 0;
   let isMouseDown = $state(false);
   let isHoveringInteractive = $state(false);
-  let dragStartX = $state(0);
+  let dragStartX = 0;
-  let dragStartY = $state(0);
+  let dragStartY = 0;
   let degrees = $state(0);
   let applyRotation = $state(false);
 
+  let lastVelocityTime = 0;
+  let consecutiveHighSpeed = 0;
+  let velocityAccumX = 0;
+  let velocityAccumY = 0;
+
   function isInteractive(el: Element | null): boolean {
     while (el) {
       const tag = el.tagName.toLowerCase();
@@ -30,7 +39,6 @@
       ) {
         return true;
       }
-
       el = el.parentElement;
     }
     return false;
@@ -43,17 +51,32 @@
     const deltaX = e.pageX - window.pageXOffset - dragStartX;
     const deltaY = e.pageY - window.pageYOffset - dragStartY;
 
-    const velocityX = mouseX - lastMouseX;
+    velocityAccumX += mouseX - lastMouseX;
-    const velocityY = mouseY - lastMouseY;
+    velocityAccumY += mouseY - lastMouseY;
 
-    const dist = Math.sqrt(velocityX * velocityX + velocityY * velocityY);
+    const now = performance.now();
+    const dt = now - lastVelocityTime;
 
-    if (!applyRotation && isMouseDown && dist > 80) applyRotation = true;
+    if (dt >= VELOCITY_WINDOW_MS) {
+      const speed = Math.sqrt(velocityAccumX ** 2 + velocityAccumY ** 2) / dt;
+
+      if (speed > SPEED_THRESHOLD) {
+        consecutiveHighSpeed++;
+        if (!applyRotation && isMouseDown && consecutiveHighSpeed >= REQUIRED_CONSECUTIVE) {
+          applyRotation = true;
+        }
+      } else {
+        consecutiveHighSpeed = 0;
+      }
+
+      velocityAccumX = 0;
+      velocityAccumY = 0;
+      lastVelocityTime = now;
+    }
 
     let newDegrees = (Math.atan2(-deltaX, deltaY) * 180) / Math.PI + 24.3;
 
     let diff = (newDegrees - degrees) % 360;
-
     if (diff < -180) diff += 360;
     if (diff > 180) diff -= 360;
 
@@ -67,26 +90,18 @@
     isHoveringInteractive = isInteractive(el);
 
     if (!isMouseDown) {
-      if (isHoveringInteractive) {
+      animate(cursorAdditive, {
-        animate(cursorAdditive, {
+        opacity: isHoveringInteractive ? 1 : 0,
-          opacity: 1,
+        duration: 800,
-          duration: 800,
+        ease: (t: number) => (t - 1) ** 5 + 1,
-          ease: (t: number) => (t - 1) ** 5 + 1,
+      });
-        });
-      } else {
-        animate(cursorAdditive, {
-          opacity: 0,
-          duration: 800,
-          ease: (t: number) => (t - 1) ** 5 + 1,
-        });
-      }
     }
 
     animate(cursor, {
       duration: smoothCursor ? $cursorSmoothness : 0,
       translateX: mouseX,
       translateY: mouseY,
-      ease: (t: number) => (t - 1) ** 5 + 1,
+      ease: (t: number) => t === 1 ? 1 : 1 - Math.pow(2, -10 * t),
     });
 
     animate(cursor, {
@@ -107,6 +122,11 @@
     dragStartX = event.clientX;
     dragStartY = event.clientY;
 
+    velocityAccumX = 0;
+    velocityAccumY = 0;
+    consecutiveHighSpeed = 0;
+    lastVelocityTime = performance.now();
+
     isMouseDown = true;
     animate(cursorInner, {
       scale: 0.9,
@@ -124,6 +144,10 @@
   const handleMouseUp = () => {
     isMouseDown = false;
     applyRotation = false;
+    consecutiveHighSpeed = 0;
+    velocityAccumX = 0;
+    velocityAccumY = 0;
+
     animate(cursorInner, {
       scale: 1,
       duration: 500,

src/lib/displayUtils.ts

@@ -1,19 +1,21 @@
-export function estimateRefreshRate(): Promise<number> {
+export async function estimateFrameRate(): Promise<number> {
   return new Promise((resolve) => {
-    const last = performance.now();
+    const samples: number[] = [];
-    let frames = 0;
+    let last = performance.now();
 
-    function loop() {
+    const tick = () => {
       const now = performance.now();
-      frames++;
+      samples.push(now - last);
+      last = now;
 
-      if (now - last >= 1000) {
+      if (samples.length < 60) {
-        resolve(frames - 2);
+        requestAnimationFrame(tick);
       } else {
-        requestAnimationFrame(loop);
+        const avgDelta = samples.reduce((a, b) => a + b) / samples.length;
+        resolve(Math.round(1000 / avgDelta));
       }
-    }
+    };
 
-    requestAnimationFrame(loop);
+    requestAnimationFrame(tick);
   });
 }

src/screens/Loading.svelte

@@ -1,6 +1,6 @@
 <script lang="ts">
   import Logo from '$assets/logo.png';
-  import { estimateRefreshRate } from '@/displayUtils';
+  import { estimateFrameRate } from '@/displayUtils';
   import {
     beatmapSets,
     currentLoadingInfo,
@@ -67,15 +67,15 @@
   };
 
   const calculateCursorSmoothness = async () => {
-    const refreshRate = await estimateRefreshRate();
+    const refreshRate = await estimateFrameRate();
     const hzMin = 60;
-    const hzMax = 144;
+    const hzMax = 500;
-    const durationMin = 70;
+    const durationMin = 350;
-    const durationMax = 180;
+    const durationMax = 600;
-
+    const clamped = Math.min(Math.max(refreshRate, hzMin), hzMax);
     const duration =
-      durationMin + ((refreshRate - hzMin) / (hzMax - hzMin)) * (durationMax - durationMin);
+      durationMin + ((clamped - hzMin) / (hzMax - hzMin)) * (durationMax - durationMin);
-
+    console.log(Math.round(duration));
     cursorSmoothness.set(Math.round(duration));
   };