1 files changed, 24 insertions, 0 deletions
diff --git a/interpolate.js b/interpolate.js
new file mode 100644
index 0000000..e6166fa
--- /dev/null
+++ b/interpolate.js
@@ -0,0 +1,24 @@
+function interpolateStyle(el, prop, cb, reset = true) {
+    if (reset) {
+        el.style.setProperty(prop, '');
+    }
+    const intact = getComputedStyle(el);
+    const start = intact.getPropertyValue(prop);
+    el.style.setProperty(prop, cb(start));
+}
+
+function itpColor(prog, target) {
+    return start => {
+        const [ sr, sg, sb ] = start.match(/[0-9]{1,}/g).map(n => parseInt(n));
+        const [ tr, tg, tb ] = target.match(/[0-9]{1,}/g).map(n => parseInt(n));
+        const [ sh, ss, sl ] = rgbToHsl(sr, sg, sb);
+        const [ th, ts, tl ] = rgbToHsl(tr, tg, tb);
+        const [ ih, is, il ] = [
+            sh + prog * (th - sh),
+            ss + prog * (ts - ss),
+            sl + prog * (tl - sl)
+        ];
+        const [ ir, ig, ib ] = hslToRgb(ih, is, il).map(n => parseInt(n));
+        return `rgb(${ir}, ${ig}, ${ib})`;
+    };
+}