1 files changed, 70 insertions, 0 deletions
diff --git a/mobile/android/base/java/org/mozilla/gecko/tabs/TabCurve.java b/mobile/android/base/java/org/mozilla/gecko/tabs/TabCurve.java
new file mode 100644
index 000000000..0b6a30d7a
--- /dev/null
+++ b/mobile/android/base/java/org/mozilla/gecko/tabs/TabCurve.java
@@ -0,0 +1,70 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko.tabs;
+
+import android.graphics.Path;
+
+/**
+ * Utility methods to draws Firefox's tab curve shape.
+ */
+public class TabCurve {
+
+    public enum Direction {
+        LEFT(-1),
+        RIGHT(1);
+
+        private final int value;
+
+        private Direction(int value) {
+            this.value = value;
+        }
+    }
+
+    // Curve's aspect ratio
+    private static final float ASPECT_RATIO = 0.729f;
+
+    // Width multipliers
+    private static final float W_M1 = 0.343f;
+    private static final float W_M2 = 0.514f;
+    private static final float W_M3 = 0.49f;
+    private static final float W_M4 = 0.545f;
+    private static final float W_M5 = 0.723f;
+
+    // Height multipliers
+    private static final float H_M1 = 0.25f;
+    private static final float H_M2 = 0.5f;
+    private static final float H_M3 = 0.72f;
+    private static final float H_M4 = 0.961f;
+
+    private TabCurve() {
+    }
+
+    public static float getWidthForHeight(float height) {
+        return (int) (height * ASPECT_RATIO);
+    }
+
+    public static void drawFromTop(Path path, float from, float height, Direction dir) {
+        final float width = getWidthForHeight(height);
+
+        path.cubicTo(from + width * W_M1 * dir.value, 0.0f,
+                     from + width * W_M3 * dir.value, height * H_M1,
+                     from + width * W_M2 * dir.value, height * H_M2);
+        path.cubicTo(from + width * W_M4 * dir.value, height * H_M3,
+                     from + width * W_M5 * dir.value, height * H_M4,
+                     from + width * dir.value, height);
+    }
+
+    public static void drawFromBottom(Path path, float from, float height, Direction dir) {
+        final float width = getWidthForHeight(height);
+
+        path.cubicTo(from + width * (1f - W_M5) * dir.value, height * H_M4,
+                     from + width * (1f - W_M4) * dir.value, height * H_M3,
+                     from + width * (1f - W_M2) * dir.value, height * H_M2);
+        path.cubicTo(from + width * (1f - W_M3) * dir.value, height * H_M1,
+                     from + width * (1f - W_M1) * dir.value, 0.0f,
+                     from + width * dir.value, 0.0f);
+    }
+}