1 files changed, 31 insertions, 0 deletions
diff --git a/client/lib/color.js b/client/lib/color.js
new file mode 100644
index 0000000..4c71cc1
--- /dev/null
+++ b/client/lib/color.js
@@ -0,0 +1,31 @@
+
+const palettes = [
+  [[0.5, 0.5, 0.5], [0.5, 0.5, 0.5], [1.0, 1.0, 1.0], [0.00, 0.33, 0.67]],
+  [[0.5, 0.5, 0.5], [0.5, 0.5, 0.5], [1.0, 1.0, 1.0], [0.00, 0.10, 0.20]],
+  [[0.5, 0.5, 0.5], [0.5, 0.5, 0.5], [1.0, 1.0, 1.0], [0.30, 0.20, 0.20]],
+  [[0.5, 0.5, 0.5], [0.5, 0.5, 0.5], [1.0, 1.0, 0.5], [0.80, 0.90, 0.30]],
+  [[0.5, 0.5, 0.5], [0.5, 0.5, 0.5], [1.0, 0.7, 0.4], [0.00, 0.15, 0.20]],
+  [[0.5, 0.5, 0.5], [0.5, 0.5, 0.5], [2.0, 1.0, 0.0], [0.50, 0.20, 0.25]],
+  [[0.8, 0.5, 0.4], [0.2, 0.4, 0.2], [2.0, 1.0, 1.0], [0.00, 0.25, 0.25]],
+]
+
+let palette = palettes[1]
+
+function channel (t, a, b, c, d, add, mul) {
+  return a + b * Math.cos(2 * Math.PI * (c * t + d)) * mul + add
+}
+
+function color (t, add=0, mul=1) {
+  let a, b, c, d
+  const rgb = []
+  for (var i = 0; i < 3; i++) {
+    a = palette[0][i]
+    b = palette[1][i]
+    c = palette[2][i]
+    d = palette[3][i]
+    rgb[i] = Math.round(channel(t, a, b, c, d, add, mul) * 255)
+  }
+  return 'rgb(' + rgb + ')'
+}
+
+export default color