basic setup

composables/useSmoothMouse.js

@@ -0,0 +1,89 @@
+import gsap from 'gsap'
+import { ref, onMounted, onBeforeUnmount } from 'vue'
+import { useWindowSize, useEventListener } from '@vueuse/core'
+
+/**
+ * Shared global raw mouse state (only set up once)
+ */
+const rawMouse = {
+    x: ref(0),
+    y: ref(0),
+    initialized: false,
+    cleanup: null,
+}
+
+const useGlobalMouseListener = () => {
+    if (!rawMouse.initialized && !import.meta.env.SSR) {
+        rawMouse.initialized = true
+        rawMouse.cleanup = useEventListener(window, 'mousemove', (e) => {
+            rawMouse.x.value = e.clientX
+            rawMouse.y.value = e.clientY
+        })
+    }
+}
+
+/**
+ * Composable for smoothed mouse position with customizable smoothing and normalization.
+ */
+export default (options) => {
+    const smoothFactor = options?.smoothFactor ?? 0.1
+    const normalize = options?.normalize ?? false
+    const callback = options?.onUpdate
+
+    const { width: wWidth, height: wHeight } = useWindowSize()
+
+    const sx = ref(0)
+    const sy = ref(0)
+
+    useGlobalMouseListener()
+
+    const getTargetX = () =>
+        normalize ? rawMouse.x.value / wWidth.value : rawMouse.x.value
+    const getTargetY = () =>
+        normalize ? rawMouse.y.value / wHeight.value : rawMouse.y.value
+
+    let tween
+    onMounted(() => {
+        if (tween) tween.kill
+
+        // Start smoothing tween
+        tween = gsap.to(
+            { x: sx.value, y: sy.value },
+            {
+                duration: 1,
+                ease: 'linear',
+                repeat: -1,
+                onUpdate: () => {
+                    const newX = gsap.utils.interpolate(
+                        sx.value,
+                        getTargetX(),
+                        smoothFactor,
+                    )
+                    const newY = gsap.utils.interpolate(
+                        sy.value,
+                        getTargetY(),
+                        smoothFactor,
+                    )
+
+                    sx.value = newX
+                    sy.value = newY
+
+                    callback?.({ sx: sx.value, sy: sy.value })
+                },
+            },
+        )
+    })
+
+    onBeforeUnmount(() => {
+        tween?.kill()
+        rawMouse.cleanup()
+        rawMouse.initialized = false
+    })
+
+    return {
+        sx,
+        sy,
+        rawX: rawMouse.x,
+        rawY: rawMouse.y,
+    }
+}