From 2496db965db4fa48197cb31c7750b2a16523ed32 Mon Sep 17 00:00:00 2001
From: triethyl <triethylammonium@pm.me>
Date: Mon, 13 Oct 2025 12:00:03 -0400
Subject: renamed theme and added content

---
 site/themes/sine/static/js/background.js | 82 ++++++++++++++++++++++++++++++++
 1 file changed, 82 insertions(+)
 create mode 100644 site/themes/sine/static/js/background.js

(limited to 'site/themes/sine/static/js/background.js')

diff --git a/site/themes/sine/static/js/background.js b/site/themes/sine/static/js/background.js
new file mode 100644
index 0000000..e9b61a2
--- /dev/null
+++ b/site/themes/sine/static/js/background.js
@@ -0,0 +1,82 @@
+document.addEventListener("DOMContentLoaded", () => {
+  const canvas = document.getElementById("background");
+  if (!canvas) return;
+  const ctx = canvas.getContext("2d");
+
+  // Grab config from the embedded <script>
+  const configEl = document.getElementById("background-config");
+  const config = configEl ? JSON.parse(configEl.textContent) : {};
+
+  // Use config values with defaults as fallback
+  const spacing    = config.spacing    ?? 24;
+  const maxRadius  = config.maxRadius  ?? 8;
+  const baseOffset = config.baseOffset ?? 120;
+  const freq       = config.freq       ?? 0.008;
+  const speed      = config.speed      ?? 0.02;
+
+  const baseAmp    = config.baseAmp    ?? 100;
+  const env1Freq   = config.envelope1Freq ?? 0.002;
+  const env1Amp    = config.envelope1Amp  ?? 120;
+  const env2Freq   = config.envelope2Freq ?? 0.0005;
+  const env2Amp    = config.envelope2Amp  ?? 200;
+
+  let t = parseFloat(localStorage.getItem("waveProgress")) || 0;
+  let widthCss = window.innerWidth;
+  let heightCss = window.innerHeight;
+  let pixelRatio = window.devicePixelRatio || 1;
+
+  function resize() {
+    widthCss = window.innerWidth;
+    heightCss = window.innerHeight;
+    pixelRatio = window.devicePixelRatio || 1;
+
+    canvas.width = Math.floor(widthCss * pixelRatio);
+    canvas.height = Math.floor(heightCss * pixelRatio);
+    canvas.style.width = widthCss + "px";
+    canvas.style.height = heightCss + "px";
+    ctx.setTransform(pixelRatio, 0, 0, pixelRatio, 0, 0);
+  }
+  window.addEventListener("resize", resize);
+  resize();
+
+  function draw() {
+    const styles = getComputedStyle(document.documentElement);
+    const fg = styles.getPropertyValue("--fg").trim();
+
+    ctx.clearRect(0, 0, widthCss, heightCss);
+    ctx.fillStyle = fg;
+
+    for (let x = 0; x <= widthCss + spacing; x += spacing) {
+      // envelope: controls crest variance
+      const envelope =
+        baseAmp
+        + Math.sin(x * env1Freq + t * 0.1) * env1Amp
+        + Math.sin(x * env2Freq + t * 0.05) * env2Amp;
+
+      const waveY = heightCss - (Math.sin(x * freq + t) * envelope + baseOffset);
+      // const waveY = Math.max(heightCss - 50, heightCss - (Math.sin(x * freq + t) * envelope + baseOffset));
+
+      for (let y = heightCss; y >= 0; y -= spacing) {
+        const dist = Math.max(0, y - waveY);
+        const radius = Math.min(maxRadius, dist / 40);
+        if (radius > 0.2) {
+          ctx.beginPath();
+          // ctx.arc(x + spacing / 2, y - spacing / 2, radius, 0, Math.PI * 2);
+          ctx.fillRect(
+            x + spacing / 2 - radius,
+            y - spacing / 2 - radius,
+            radius * 2,
+            radius * 2
+          );
+          ctx.fill();
+        }
+      }
+    }
+
+    t += speed;
+    localStorage.setItem("waveProgress", t);
+    requestAnimationFrame(draw);
+  }
+
+  draw();
+});
-- 
cgit v1.2.3