From 74f7b434865c2d758c7b1cd5f52f4c96b76d03fb Mon Sep 17 00:00:00 2001
From: Simone <lucenz@proton.me>
Date: Sat, 15 Aug 2026 01:32:33 +0200
Subject: [PATCH] fix(web): bound OKLCH gamut mapping (#6485)

Co-authored-by: Simone <185146821+Lucenx9@users.noreply.github.com>
---
 apps/web/src/themePalette.test.ts | 12 ++++++++++++
 apps/web/src/themePalette.ts      |  6 +++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/apps/web/src/themePalette.test.ts b/apps/web/src/themePalette.test.ts
index 95ce10af9316a49c2dfccdb01d7ea42d07e7a1e0..3c5897c70152e727bcf8780f0ad873531ced9d66 100644
--- a/apps/web/src/themePalette.test.ts
+++ b/apps/web/src/themePalette.test.ts
@@ -246,6 +246,18 @@ describe("theme files", () => {
     }
   });
 
+  it("gamut maps extreme finite OKLCH chroma from theme files", () => {
+    const theme = parseThemeFile({
+      version: THEME_FILE_VERSION,
+      name: "Extreme chroma",
+      appearance: "light",
+      colors: { accent: "oklch(0.5 1e303 0)" },
+    });
+
+    expect(theme.colors.accent).toBe("oklch(0.5 1e+303 0)");
+    expect(themeColorToHex(theme.colors.accent)).toBe("#b5005e");
+  });
+
   it("rejects unknown roles and invalid color values", () => {
     expect(() =>
       parseThemeFile({
diff --git a/apps/web/src/themePalette.ts b/apps/web/src/themePalette.ts
index 00b29dce83bafb6b1f651183a6112052a8b25fd2..7bf4f0426bd398ac6eb84d0c3c44943ee79d20d5 100644
--- a/apps/web/src/themePalette.ts
+++ b/apps/web/src/themePalette.ts
@@ -902,7 +902,11 @@ function mapThemeOklchToSrgbGamut(color: ThemeOklch): ThemeOklch {
 
   let low = 0;
   let high = color.C;
-  const steps = Math.max(1, Math.ceil(Math.log2(Math.max(color.C, 0.000001) / 0.000001)));
+  const chromaResolution = 0.000001;
+  const steps = Math.max(
+    1,
+    Math.ceil(Math.log2(Math.max(color.C, chromaResolution)) - Math.log2(chromaResolution)),
+  );
   for (let step = 0; step < steps; step += 1) {
     const mid = (low + high) / 2;
     if (isInGamut(mid)) low = mid;
-- 
2.54.0